Iodine Supplementation in Mildly Iodine-Deficient Pregnant Women Does Not Improve Maternal Thyroid Function or Child Development : A Secondary Analysis of a Randomized Controlled Trial
Verhagen, Nicole J.E. ; Gowachirapant, Sueppong ; Winichagoon, Pattanee ; Andersson, Maria ; Melse-Boonstra, Alida ; Zimmermann, Michael B. - \ 2020
Frontiers in Endocrinology 11 (2020). - ISSN 1664-2392
brain development - children - cognition - infants - iodine deficiency - pregnancy - supplementation - thyroid
Background: Iodine deficiency during pregnancy may be associated with lower offspring IQ, but there are few data on the safety and efficacy of maternal iodine supplementation on child development. In a previously reported multi-center randomized trial conducted in Thailand and India, we assessed the effect of iodine supplementation in mildly iodine-deficient pregnant women on offspring development. In this secondary analysis of that trial, we report data only from the Thai pregnant women in the study, who were more iodine deficient at entry. Methods: Pregnant women in Bangkok, Thailand, were randomized to receive daily 200 μg oral iodine or placebo until delivery. We assessed thyroid size and thyroid function during pregnancy and cognitive and motor development at ages 1, 2, and 5.7 years. The trial was registered at www.clinicaltrials.gov/NCT00791466. Findings: Women (n = 514) entered the trial between November 2008 and March 2011 at a mean ± SD gestational age of 11 ± 2.8 weeks; their median (IQR) UIC was 112 (75, 170) μg/L. Mean compliance with supplementation was 88%. We assessed 397 mothers in the 3rd trimester, 231 infants at age 2 y, and 157 children at mean age 5.7 y. During pregnancy, there was a slightly greater decrease in free and total thyroxine concentrations in the iodine group (p < 0.05). At age 2 years, the iodine group had borderline lower scores for combined fine and gross motor function (p = 0.05), but there were no other significant differences in development. At 5.7 years, there were no significant group differences in child development. Conclusion: Daily iodine supplementation in mildly iodine deficient pregnant women was associated with small negative effects on maternal thyroxine concentrations, but did not affect child development. The safety and efficacy of iodine supplementation in mildly-iodine deficient pregnant women needs to be evaluated further in large randomized controlled trials.
Propionic acid and not caproic acid, attenuates nonalcoholic steatohepatitis and improves (cerebro) vascular functions in obese Ldlr−/−.Leiden mice
Tengeler, Anouk C. ; Gart, Eveline ; Wiesmann, Maximilian ; Arnoldussen, Ilse A.C. ; Duyvenvoorde, Wim van; Hoogstad, Marloes ; Dederen, Pieter J. ; Verweij, Vivienne ; Geenen, Bram ; Kozicz, Tamas ; Kleemann, Robert ; Morrison, Martine C. ; Kiliaan, Amanda J. - \ 2020
FASEB Journal 34 (2020)7. - ISSN 0892-6638 - p. 9575 - 9593.
cerebral vasoreactivity - cognition - liver fibrosis - neuroimaging - obesity
The obesity epidemic increases the interest to elucidate impact of short-chain fatty acids on metabolism, obesity, and the brain. We investigated the effects of propionic acid (PA) and caproic acid (CA) on metabolic risk factors, liver and adipose tissue pathology, brain function, structure (by MRI), and gene expression, during obesity development in Ldlr−/−.Leiden mice. Ldlr−/−.Leiden mice received 16 weeks either a high-fat diet (HFD) to induce obesity, or chow as reference group. Next, obese HFD-fed mice were treated 12 weeks with (a) HFD + CA (CA), (b) HFD + PA (PA), or (c) a HFD-control group. PA reduced the body weight and systolic blood pressure, lowered fasting insulin levels, and reduced HFD-induced liver macrovesicular steatosis, hypertrophy, inflammation, and collagen content. PA increased the amount of glucose transporter type 1-positive cerebral blood vessels, reverted cerebral vasoreactivity, and HFD-induced effects in microstructural gray and white matter integrity of optic tract, and somatosensory and visual cortex. PA and CA also reverted HFD-induced effects in functional connectivity between visual and auditory cortex. However, PA mice were more anxious in open field, and showed reduced activity of synaptogenesis and glutamate regulators in hippocampus. Therefore, PA treatment should be used with caution even though positive metabolic, (cerebro) vascular, and brain structural and functional effects were observed.
Experimental translocations to low predation lead to non-parallel increases in relative brain size
Mitchell, David J. ; Vega-Trejo, Regina ; Kotrschal, Alexander - \ 2020
Biology Letters 16 (2020)1. - ISSN 1744-9561 - 1 p.
cognition - convergent evolution - predator–prey interactions - telencephalon
Predation is a near ubiquitous factor of nature and a powerful selective force on prey. Moreover, it has recently emerged as an important driver in the evolution of brain anatomy, though population comparisons show ambiguous results with considerable unexplained variation. Here, we test the reproducibility of reduced predation on evolutionary trajectories of brain evolution. We make use of an introduction experiment, whereby guppies (Poecilia reticulata) from a single high predation stream were introduced to four low predation streams. After 8-9 years of natural selection in the wild and two generations of common garden conditions in the laboratory, we quantified brain anatomy. Relative brain region sizes did not differ between populations. However, we found a general increase and striking variation in relative brain size of introduced populations, which varied from no change to a 12.5% increase in relative brain weight, relative to the ancestral high predation population. We interpret this as evidence for non-parallel evolution, which implies a weak or inconsistent association of relative brain size with fitness in low predation sites. The evolution of brain anatomy appears sensitive to unknown environmental factors, or contingent on either chance events or historical legacies of environmental change.
Supplementary material from "Experimental translocations to low predation lead to non-parallel increases in relative brain size"
Mitchell, David J. ; Vega-Trejo, Regina ; Kotrschal, Alexander - \ 2019
Wageningen University & Research
telencephalon - cognition - convergent evolution - predator-prey interactions
Predation is a near ubiquitous factor of nature and a powerful selective force on prey. Moreover, it has recently emerged as an important driver in the evolution of brain anatomy, though population comparisons show ambiguous results with considerable unexplained variation. Here, we test the reproducibility of reduced predation on evolutionary trajectories on brain evolution. We make use of an introduction experiment, whereby guppies (Poecilia reticulata) from a single high predation stream were introduced to four low predation streams. After 8–9 years of natural selection in the wild and two generations of common garden conditions in the laboratory, we quantified brain anatomy. Relative brain region sizes did not differ between populations. However, we found a general increase and striking variation in relative brain size of introduced populations, which varied from no change to a 12.5% increase in relative brain weight, relative to the ancestral high predation population. We interpret this as evidence for non-parallel evolution, which implies a weak or inconsistent association of relative brain size with fitness in low predation sites. The evolution of brain anatomy appears sensitive to unknown environmental factors, or contingent on either chance events or historical legacies of environmental change.
The Mediterranean, Dietary Approaches to Stop Hypertension (DASH), and Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) Diets Are Associated with Less Cognitive Decline and a Lower Risk of Alzheimer's Disease-A Review
Brink, Annelien C. van den; Brouwer-Brolsma, Elske M. ; Berendsen, Agnes A.M. ; Rest, Ondine van de - \ 2019
Advances in Nutrition 10 (2019)6. - ISSN 2161-8313 - p. 1040 - 1065.
Alzheimer's disease - cognition - cognitive decline - DASH - dementia - dietary components - dietary patterns - Mediterranean - MIND - nutrition
As there is currently no cure for dementia, there is an urgent need for preventive strategies. The current review provides an overview of the existing evidence examining the associations of the Mediterranean, Dietary Approaches to Stop Hypertension (DASH), and Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diets and their dietary components with cognitive decline, dementia, and Alzheimer's disease (AD). A systematic search was conducted within Ovid Medline for studies published up to 27 March 2019 and reference lists from existing reviews and select articles were examined to supplement the electronic search results. In total, 56 articles were included. Higher adherence to the Mediterranean diet was associated with better cognitive scores in 9 of 12 cross-sectional studies, 17 of 25 longitudinal studies, and 1 of 3 trials. Higher adherence to the DASH diet was associated with better cognitive function in 1 cross-sectional study, 2 of 5 longitudinal studies, and 1 trial. Higher adherence to the MIND diet was associated with better cognitive scores in 1 cross-sectional study and 2 of 3 longitudinal studies. Evidence on the association of these dietary patterns with dementia in general was limited. However, higher adherence to the Mediterranean diet was associated with a lower risk of AD in 1 case-control study and 6 of 8 longitudinal studies. Moreover, higher adherence to the DASH or MIND diets was associated with a lower AD risk in 1 longitudinal study. With respect to the components of these dietary patterns, olive oil may be associated with less cognitive decline. In conclusion, current scientific evidence suggests that higher adherence to the Mediterranean, DASH, or MIND diets is associated with less cognitive decline and a lower risk of AD, where the strongest associations are observed for the MIND diet.
The Importance of Maternal Folate Status for Brain Development and Function of Offspring
Naninck, Eva F.G. ; Stijger, Pascalle C. ; Brouwer-Brolsma, Elske M. - \ 2019
Advances in Nutrition 10 (2019)3. - ISSN 2161-8313 - p. 502 - 519.
brain - cognition - developmental - folate - folic acid - maternal - neuropsychological - prenatal
The importance of an adequate periconceptional maternal folate status to prevent fetal neural tube defects has been well demonstrated and resulted in the recommendation for women to use folic acid supplements during the periconception period. The importance of maternal folate status for offspring neurodevelopment and brain health is less well described. We reviewed the current evidence linking maternal folate status before conception and during pregnancy with neurodevelopment and cognition of the offspring. We discuss both animal and human studies. Preclinical research revealed the importance of maternal folate status for several key processes required for normal neurodevelopment and brain functioning in the offspring, including DNA synthesis, regulation of gene expression, synthesis of phospholipids and neurotransmitters, and maintenance of healthy plasma homocysteine concentrations. Human observational studies are inconclusive; about half have shown a positive association between maternal folate status and cognitive performance of offspring. Whereas some studies suggest a positive association between maternal folate intake and cognition of offspring during childhood, data from interventional studies are too limited to conclude that there is a direct effect. Future preclinical studies are needed to help us characterize the behavioral effects, understand the underlying mechanisms, and to establish an optimal dosage and time window of folate supplementation. Moreover, more conclusive data from well-designed human observational studies and randomized controlled trials are needed to determine whether current recommendations for folic acid supplementation during pregnancy cover the needs for normal cognitive development in the offspring.
Dietary Patterns Are Related to Clinical Characteristics in Memory Clinic Patients with Subjective Cognitive Decline: The SCIENCe Project
Wesselman, Linda M.P. ; Doorduijn, Astrid S. ; Leeuw, Francisca A. de; Verfaillie, Sander C.J. ; Leeuwenstijn-Koopman, Mardou van; Slot, Rosalinde E.R. ; Kester, Maartje I. ; Prins, Niels D. ; Rest, Ondine van de; Schueren, Marian A.E. van der; Scheltens, Philip ; Sikkes, Sietske A.M. ; Flier, Wiesje M. van der - \ 2019
Nutrients 11 (2019)5. - ISSN 2072-6643 - 10 p.
Alzheimer’s disease - cognition - memory clinic - nutrition - prevention - subjective cognitive decline
As nutrition is one of the modifiable risk factors for cognitive decline, we studied the relationship between dietary quality and clinical characteristics in cognitively normal individuals with subjective cognitive decline (SCD). We included 165 SCD subjects (age: 64 ± 8 years; 45% female) from the SCIENCe project, a prospective memory clinic based cohort study on SCD. The Dutch Healthy Diet Food Frequency Questionnaire (DHD-FFQ) was used to assess adherence to Dutch guidelines on vegetable, fruit, fibers, fish, saturated fat, trans fatty acids, salt and alcohol intake (item score 0-10, higher score indicating better adherence). We measured global cognition (Mini Mental State Examination), cognitive complaints (Cognitive Change Index self-report; CCI) and depressive symptoms (Center for Epidemiologic Studies Depression Scale; CES-D). Using principal component analysis, we identified dietary components and investigated their relation to clinical characteristics using linear regression models adjusted for age, sex and education. We identified three dietary patterns: (i) "low-Fat-low-Salt", (ii) "high-Veggy", and (iii) "low-Alcohol-low-Fish". Individuals with lower adherence on "low-Fat-low-Salt" had more depressive symptoms (β -0.18 (-2.27--0.16)). Higher adherence to "high-Veggy" was associated with higher MMSE scores (β 0.30 (0.21-0.64)). No associations were found with the low-Alcohol-low-Fish component. We showed that in SCD subjects, dietary quality was related to clinically relevant outcomes. These findings could be useful to identify individuals that might benefit most from nutritional prevention strategies to optimize brain health.
Changes in the influence of affect and cognition over time on consumer attitude formation toward nanotechnology : A longitudinal survey study
Giesen, Roxanne I. van; Fischer, Arnout R.H. ; Trijp, Hans C.M. van - \ 2018
Public Understanding of Science 27 (2018)2. - ISSN 0963-6625 - p. 168 - 184.
affect - attitudes - cognition - longitudinal survey - nanotechnology
Insights into how consumer attitudes toward nanotechnology are formed and develop are crucial for understanding and anticipating possible barriers in consumer acceptance of nanotechnology applications. In this study, the influence of affect and cognition on overall opinion is investigated longitudinally for emerging nanotechnologies, and compared with conventional technologies. Overall, in attitude formation toward nanotechnology applications, people rely relatively more on affect than cognition. Over time, reliance on affect decreases whereas reliance on cognition increases for nanotechnology. This suggests that over time nanotechnology applications have become somewhat more integrated within people’s already existing knowledge structure. However, for conventional technologies the influence of affect and cognition on overall attitude remains stable over time. The current study shows that it is essential to address both affective and cognitive aspects of public opinion of nanotechnology.
Dietary patterns for healthier cognitive ageing
Berendsen, Agnes A.M. - \ 2017
Wageningen University. Promotor(en): C.P.G.M. de Groot; E.J.M. Feskens, co-promotor(en): O. van de Rest. - Wageningen : Wageningen University - ISBN 9789463436014 - 190
meal patterns - feeding habits - aging - cognition - health - food supplements - dementia - nutritional intervention - elderly - elderly nutrition - nutrition and health - maaltijdpatronen - voedingsgewoonten - verouderen - kenvermogen - gezondheid - voedselsupplementen - dementie - maatregel op voedingsgebied - ouderen - ouderenvoeding - voeding en gezondheid
With ageing of our population and the accompanying increase in the number of people living with dementia, it is important to find modifiable risk factors to postpone the onset of cognitive decline. Diet has been proposed such a modifiable risk factor. To date, numerous studies have been conducted demonstrating a possible role of specific nutrients and foods in cognitive functioning. However, as people do not consume single nutrients, the research field has shifted towards studying dietary patterns in which synergistic effects of single nutrients and/or foods can be studied. The main aim of this thesis was to study the association of healthful dietary patterns with cognitive functioning. In addition, nutrient intake inadequacies were assessed and the potential to change dietary intake in older adults aged 65 years and older was studied.
Chapter 2 describes nutrient intake of 245 Dutch adults aged 65-80 years. We identified the contribution of nutrient dense foods, fortified foods and dietary supplements to the total intake of micronutrients. Nutrient density of foods was evaluated using the Nutrient Rich Food score 9.3. Nutrient intake inadequacies were observed for vitamin D, vitamin B6 and selenium. Conventional foods were the main source of vitamin D, vitamin B6 and selenium intake. Foods with the highest nutrient density contributed most to total vitamin B6 intake. In order to optimize nutrient intakes of elderly, combinations of natural food sources, fortified foods and dietary supplements should be considered.
Chapter 3 provides a systematic review of the literature on human studies up to May 2014 that examined the role of dietary patterns in relation to cognitive decline or dementia. The results demonstrate that better adherence to a Mediterranean diet was associated with less cognitive decline, dementia or Alzheimer’s Disease (AD) in four out of six cross-sectional studies, six out of 12 longitudinal studies, one trial and three meta-analyses. Other healthy dietary patterns, among which the Healthy Diet Indicator, have shown to be associated with reduced cognitive decline and/or a reduced risk of dementia in all six cross-sectional studies and six out of eight longitudinal studies. The conclusion of this literature review was that more conclusive evidence is needed to come to more targeted and detailed dietary guidelines to prevent or postpone cognitive decline.
In chapter 4 the association between the Healthy Diet Indicator (HDI) and cognitive functioning in older adults from three different cohort studies was investigated. The cohorts included in total 21,837 subjects from Europe (SENECA and the Rotterdam Study [RS]) and the Unites States (Nurses’ Health Study [NHS]). Cognitive functioning was measured using the Mini-Mental State Examination (MMSE) in SENECA and RS, and the Telephone Interview for Cognitive Status (TICS) in NHS. In all three cohorts, the HDI was not significantly associated with cognitive decline, nor with cognitive function.
In chapter 5 the association of long-term adherence to the Dietary Approaches to Stop Hypertension (DASH) diet with cognitive function and decline in older American women was examined. A total of 16,144 women from the Nurses’ Health Study, aged ≥70 years, who underwent cognitive testing a total of 4 times by telephone from 1995-2001 (baseline), with multiple dietary assessments between 1984 and the first cognitive exam were studied. Greater adherence to long-term DASH score was significantly associated with better average global cognition, verbal memory and TICS score at older ages, but not with cognitive decline.
In chapter 6, the same cohort as in chapter 5 was studied to examine the association between long-term adherence to a recently developed Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet with cognitive function and decline. Higher MIND diet scores were associated with better verbal memory at older ages, but not with cognitive decline over 6 years in global cognition, verbal memory or TICS.
Chapter 7 provides an overview of the NU-AGE (NUtrients and AGEing) dietary intervention study. The NU-AGE study is a randomized one-year intervention in 1,250 apparently healthy, independently living European subjects aged 65 to 80 years. Subjects were randomised into either the intervention group or the control group. Participants in the intervention group received dietary advice aimed at meeting the dietary recommendations of the ageing population. At the start of this thesis, the NU-AGE study was the first dietary intervention investigating the effect of a whole diet and providing targeted dietary recommendations for optimal health and quality of life in apparently healthy European elderly.
In chapter 8, we evaluated if the NU-AGE intervention could be effective to shift the dietary intake of apparently healthy older adults aged 65-80 years living in Italy, the UK, the Netherlands, Poland, and France towards a more healthful diet. The NU-AGE index was created to assess adherence to the NU-AGE diet. At baseline and after one-year follow-up dietary intake was assessed by means of 7-day food records. In total, 1,296 participants were randomized and 1,145 participants completed the intervention (571 in intervention group, 570 in control group). After one-year follow-up, the intervention group improved mean intake of 13 out of 16 dietary recommendations of the NU-AGE diet (p<0.05) with a significant increase of the total NU-AGE index, compared to the control group (mean change in NU-AGE index 21.3±15.9, p<0.01). The NU-AGE dietary intervention, based on dietary recommendations for older adults, may be a feasible strategy to improve dietary intake in an ageing European population.
Chapter 9 shows the results of the NU-AGE parallel randomized dietary intervention study on cognitive functioning in the Dutch NU-AGE subpopulation, including 252 older adults aged 65-80 years (123 intervention, 129 control). The primary outcome was one-year change in global cognition and in four cognitive domains as measured through a comprehensive neuropsychological test battery. Comparing the intervention with the control group, there was no effect of the intervention on cognitive functioning.
In chapter 10 the main findings of this thesis were summarized and a reflection on methodological aspects was given. When grading the reported associations in previous studies and studies in this thesis, it was concluded that there is probable evidence for a role of the Mediterranean diet on cognitive functioning. For the DASH and MIND diet there is a possible link with cognitive functioning; for the HDI and the NU-AGE diet there is no sufficient evidence yet to conclude that there is a relation with cognitive functioning. Not only is there a need for well-designed intervention and prospective studies, we also call for communication strategies to the general public about the consumption of healthier diets to not only impact cardiovascular but also potentially impact brain health as many individuals will face progressive cognitive decline in the near future.
Cortical phase changes measured using 7-T MRI in subjects with subjective cognitive impairment, and their association with cognitive function
Rooden, Sanneke van; Buijs, Mathijs ; Vliet, Marjolein E. van; Versluis, Maarten J. ; Webb, Andrew G. ; Oleksik, Ania M. ; Wiel, Lotte van de; Middelkoop, Huub A.M. ; Blauw, Gerard Jan ; Weverling-Rynsburger, Annelies W.E. ; Goos, Jeroen D.C. ; Flier, Wiesje M. van der; Koene, Ted ; Scheltens, Philip ; Barkhof, Frederik ; Nieuwerth-van de Rest, Ondine ; Slagboom, P.E. ; Buchem, Mark A. van; Grond, Jeroen van der - \ 2016
NMR in Biomedicine 29 (2016)9. - ISSN 0952-3480 - p. 1289 - 1294.
AD pathology - Alzheimer's disease - brain imaging - cognition - human 7-T MRI - phase - subjective cognitive impairment
Studies have suggested that, in subjects with subjective cognitive impairment (SCI), Alzheimer's disease (AD)-like changes may occur in the brain. Recently, an in vivo study has indicated the potential of ultra-high-field MRI to visualize amyloid-beta (Aβ)-associated changes in the cortex in patients with AD, manifested by a phase shift on T2*-weighted MRI scans. The main aim of this study was to investigate whether cortical phase shifts on T2*-weighted images at 7 T in subjects with SCI can be detected, possibly implicating the deposition of Aβ plaques and associated iron. Cognitive tests and T2*-weighted scans using a 7-T MRI system were performed in 28 patients with AD, 18 subjects with SCI and 27 healthy controls (HCs). Cortical phase shifts were measured. Univariate general linear modeling and linear regression analysis were used to assess the association between diagnosis and cortical phase shift, and between cortical phase shift and the different neuropsychological tests, adjusted for age and gender. The phase shift (mean, 1.19; range, 1.00–1.35) of the entire cortex in AD was higher than in both SCI (mean, 0.85; range, 0.73–0.99; p <0.001) and HC (mean, 0.94; range, 0.79–1.10; p <0.001). No AD-like changes, e.g. increased cortical phase shifts, were found in subjects with SCI compared with HCs. In SCI, a significant association was found between memory function (Wechsler Memory Scale, WMS) and cortical phase shift (β = –0.544, p = 0.007). The major finding of this study is that, in subjects with SCI, an increased cortical phase shift measured at high field is associated with a poorer memory performance, although, as a group, subjects with SCI do not show an increased phase shift compared with HCs. This increased cortical phase shift related to memory performance may contribute to the understanding of SCI as it is still unclear whether SCI is a sign of pre-clinical AD.
Affect and cognition in attitude formation towards familiar and unfamiliar attitude objects: the case of nanotechnology
Giesen, R.I. van - \ 2015
Wageningen University. Promotor(en): Hans van Trijp, co-promotor(en): Arnout Fischer. - Wageningen : Wageningen University - ISBN 9789462573390 - 187
nanotechnologie - houding van consumenten - attitudes - besluitvorming - technologie - voedseltechnologie - kennisniveau - kenvermogen - nanotechnology - consumer attitudes - attitudes - decision making - technology - food technology - knowledge level - cognition
Together, the chapters in this thesis show that although the default is to rely on affect, in attitude formation toward unfamiliar attitude objects, people are able to draw on cognitive inferences provided that there are enough cues available (e.g. product context, high Need for Cognition, or being more often exposed). In addition, whether people rely on affect or cognition depends on which process is the easiest. The attitude component which is decisive in the attitude formation process requires the least elaborate process. This thesis contributes to a better process understanding as both affective-cognitive and deliberative-intuitive dimensions were simultaneously studied. Finally, it is concluded that attitudes toward unfamiliar attitude objects, in this case nanotechnology applications, are still subject to change. This has implications for communication about new technologies, as it is important to address both affective and cognitive aspects.
Effect of iodine supplementation in Indian pregnant women on maternal and newborn thyroid function and cognitive development
Jaikrishna, N. - \ 2015
Wageningen University. Promotor(en): Michael Zimmermann, co-promotor(en): Alida Melse-Boonstra; K Srinivasan. - Wageningen : Wageningen University - ISBN 9789462573338 - 244
jodium - maternale voeding - zwangerschap - voeding - hypothyreoïdie - schildklierziekten - schildklierwerking - jodiumhoudend zout - minerale supplementen - kenvermogen - cognitieve ontwikkeling - mineraaltekorten - voedingsstoffentekorten - iodine - maternal nutrition - pregnancy - nutrition - hypothyroidism - thyroid diseases - thyroid function - iodized salt - mineral supplements - cognition - cognitive development - mineral deficiencies - nutrient deficiencies
Background: Iodine is a key nutrient in neurodevelopment, and the fetus is entirely dependent on the iodine intake of the mother to fulfill this important requirement for proper brain function. While this is clearly known, it is uncertain if maternal iodine nutrition should be monitored separately against what is in current practice in public health programs to control iodine deficiency. Also, it is unclear whether it is beneficial to supplement pregnant women with iodine in mild-to moderately iodine deficient and also iodine sufficient areas. Finally, the role of thyroid dysfunction in depression during pregnancy is uncertain.
Objectives: 1) to determine whether iodine supplementation to pregnant women improves maternal and newborn thyroid function, pregnancy outcome, birth weight, infant growth and cognitive performance; 2) to assess iodine intake and potential determinants of intake, in pregnant women and their children who were sharing all meals; 3) to measure thyroid status during pregnancy and assess potential determinants of maternal thyroid function including iodine status, thyroid autoimmunity, body weight and anemia; 4) to assess the association of maternal depression, and thyroid function during pregnancy.
Methods: 1) In a randomized placebo controlled trial (RCT), the MITCH (Maternal Iodine Supplementation and its Effects on Thyroid function and CHild Development) study, pregnant women, gestational age ≤14 weeks, in Bangalore, India, were randomized to receive either a daily supplement of 200 µg oral iodine or placebo from enrolment until delivery. Women were followed through delivery, and then with postnatal follow-up of their infants at 6 weeks, 1 and 2 year. Early neonatal development was assessed using the Neonatal Behavioral Assessment Scale (NBAS) at 6 weeks of age; neurocognitive assessment was done using the Bayley Scales of Infant Development (BSID III) at 1 and 2 years, and BRIEF-P (Behavior Rating Inventory of Executive Function) at 2 years; 2) A cross-sectional study comparing iodine status of pregnant women and their children, who were sharing all meals in Bangalore, India; 3) A cross-sectional study among 334 pregnant women ≤14 weeks of gestation, in Bangalore, India, who were screened for the RCT; 4) Secondary analysis of the longitudinal data on 318 pregnant women in the RCT.
Results: 1) In the RCT, there were no significant differences between groups in maternal thyroid function tests or thyroid volume during gestation. The prevalence of thyroid dysfunction or anti-TPO antibodies did not differ significantly during gestation and postpartum. Postpartum, there were no significant differences between the maternal and infant groups in thyroid function, birth outcomes or UIC. Neonates whose mothers received iodine supplementation during pregnancy had better orientation scores at 6 weeks of age and lower scores of inhibition suggesting better executive function at 2 years of age although neurocognitive development on the BSID III were not significantly different between groups; 2) In the pilot study, a) median UIC in pregnant women was 172 µg/L, b) the median UIC was >150 µg/L in all trimesters and c) thyroid size was not significantly different across trimesters; the median UIC in children was 220µg/L, indicating ‘more than adequate’ iodine intake at this age. Median UIC was significantly higher in children than in their mothers (p=0.008). 3) In the cross-sectional study, 21% women were vegetarian, 19% were anemic and 23% were overweight or obese. Iodized salt was used by 98% of women and they were iodine sufficient, median UIC was 184.2 µg/L and all had normal thyroid volume. However, 18% of women had thyroid insufficiency: 3.7% had overt hypothyroidism (83% with positive TPO-Ab), 9.2% had subclinical hypothyroidism and 5.2% had hypothyroxinemia. Women consuming vegetarian diets did not have significantly lower iodine intakes or higher risk of hypothyroidism than those consuming mixed diets, but overweight/obesity and anemia predicted thyroid insufficiency; 4) In the longitudinal study, there was no significant difference in depressive symptoms between the iodine intervention and placebo groups. Women with depressive symptoms had significantly lower serum TSH compared to women without depressive symptoms in the first trimester. Pregnant women with prenatal depressive symptoms had a significantly higher number of medical symptoms.
Conclusion: 1) Iodine supplementation in mildly iodine deficient and in iodine sufficient pregnant women was well-accepted and safe and did not increase the risk of excess iodine intake, hyper- or hypothyroidism, or thyroid autoimmunity. Though there were no significant effects of iodine supplementation on neonatal and maternal thyroid function and birth outcomes, there were modest effects on neurocognitive development of children as assessed by executive function of children at 2 years. Thus, additional follow-up of these children for neurocognitive testing at a later age when development and cognitive testing is more reliable would provide valuable add on information; 2) The iodized salt program in Bangalore, India was providing adequate iodine to women throughout pregnancy, at the expense of higher iodine intake in their children, suggesting that the current WHO/UNICEF/ICCIDD cut-off for median UIC in children indicating more-than-adequate intake may need to be reconsidered; 3) Despite iodine sufficiency, many pregnant women had thyroid insufficiency predicted by low hemoglobin and higher BMI. The prevalence of overt hypothyroidism was >5-fold higher than reported in other iodine-sufficient populations of pregnant women, thus, screening of maternal thyroid function should be considered in antenatal care at hospitals in Bangalore, India; 4) Although iodine supplementation did not affect maternal depression, we highlighted the need for systemic screening for prenatal depression during antenatal visits as it is an independent risk factor for later development of clinical depression
Use of an Interculturally Enriched Collaboration Script in Computer-Supported Collaborative Learning in Higher Education
Popov, V. ; Biemans, H.J.A. ; Kuznetsov, A.N. ; Mulder, M. - \ 2014
Technology, Pedagogy and Education 23 (2014)3. - ISSN 1475-939X - p. 349 - 374.
environment - behaviors - cognition - students - outcomes - culture - dyads - teams - cscl
In this exploratory study, the authors introduced an interculturally enriched collaboration script (IECS) for working in culturally diverse groups within a computer-supported collaborative learning (CSCL) environment and then assessed student online collaborative behaviour, learning performance and experiences. The question was if and how these variables differed for the groups that used an IECS versus groups that used a general collaboration script (CS) that did not include intercultural elements. Using a web conferencing tool, 47 students from a university in Ukraine and a university in the Netherlands worked together in groups to develop project plans on an environmental problem. The groups in the IECS condition showed a higher frequency of so-called contributing behaviour but a lower frequency of planning behaviour, seeking input and social interaction than the groups in the CS condition. The IECS groups also produced better project plans than the CS groups. Future study using a similar experimental set-up but with larger samples is recommended to see if the present results can be replicated.
Nutrition and cognition in older adults : studies on the role of glucose, sucrose, protein, vitamin B12 and folic acid
Zwaluw, N.L. van der - \ 2014
Wageningen University. Promotor(en): Lisette de Groot, co-promotor(en): Ondine van de Rest; Rosalie Dhonukshe-Rutten. - Wageningen : Wageningen University - ISBN 9789462571075 - 184
ouderenvoeding - voeding - ouderen - kenvermogen - glucose - sucrose - eiwittoevoegingen - vitamine b12 - dementie - elderly nutrition - nutrition - elderly - cognition - glucose - sucrose - protein supplements - vitamin b12 - dementia
The age-related cognitive decline and the increase in dementia patients are large problems in societies with growing ageing populations. No cure is present for dementia, while the available medication only focuses on alleviating symptoms. It is therefore of major importance to find risk factors that can modify the development of cognitive decline and dementia. Pre-clinical and observational studies suggest a role for nutrients. Evidence derived from randomized controlled trials (RCTs) is, however, limited and equivocal with most studies showing no effect and only a few studies showing a beneficial effect of a nutritional intervention. In the current thesis, we investigated the acute and longer-term effects of different nutrients, i.e. glucose and sucrose, protein, resistance-type exercise training with or without protein, and vitamin B12 and folic acid in order to optimize and preserve cognitive functions in non-demented elderly people.
A comprehensive literature review was performed on the acute effects of glucose and sucrose on cognitive performance (Chapter 2). Glucose is the most important fuel for the brain, and as such, manipulation of the supply of glucose may affect cognitive functions. The main conclusion of our review was that a glucose load may have a short-term beneficial effect on episodic memory. Enhancing effects on other cognitive domains were less clear, partly due to the small number of studies examining these effects. Limited research was also done on the possible effects of sucrose on cognitive functions. Therefore, we investigated the acute effects of 50 g of glucose and 100 g of sucrose on a broad spectrum of cognitive functions reflecting performance on episodic memory, working memory, attention and information processing speed, and executive functions (Chapter 3). This was done by a cross-over study in 43 elderly participants who had self-reported memory complaints. In contrast to the conclusion of our review, we did not observe an effect of glucose or sucrose on episodic memory, though we showed a beneficial effect of sucrose on attention and information processing speed.
Protein supplementation was the next nutritional intervention that was investigated. Several amino acids are precursors for neurotransmitters, and their supply may affect the synthesis and release of these neurotransmitters, and may consequently affect cognitive performance. A 24-week randomized placebo-controlled trial was carried out in 65 frail and pre-frail elderly people (Chapter 4). The protein supplementation included twice a day 15 grams of protein in the form of a drink. Reaction time improved more in the protein group compared to the placebo group, but the scores on the cognitive domains, i.e. episodic memory, attention and working memory, information processing speed, and executive functions, or the other single test scores, did not differ between treatment groups. In addition, we investigated the effects of 24 weeks resistance-type exercise training with and without protein supplementation in pre-frail and frail elderly people (Chapter 5). Exercise training without extra protein (n=62) improved performance on the domain attention and working memory. Exercise training together with protein supplementation (n=65) improved performance on information processing speed.
Last, the role of vitamin B12 and folate on cognitive health was investigated. Low levels of these nutrients can increase homocysteine levels, which is a suggested risk factor for cognitive decline. The effect of daily supplementation with 500 µg vitamin B12 and 400 µg folic acid was investigated in 2,919 participants for two years (Chapter 6). Global cognitive function and episodic memory were assessed in the total study population, whereas extensive neuropsychological testing was done in a subpopulation (n=856). B-vitamin supplementation did not improve cognitive domain scores. Only a small, though significant, effect was observed on global cognitive performance, measured by the Mini-Mental State Examination, but this was suggested to be due to chance. Brain MRI scans were made in a subgroup (n=218) after two years of intervention to obtain volumetric measures of grey and white matter, and total brain volume (Chapter 7). We investigated the cross-sectional associations between follow-up levels of folate, homocysteine and three vitamin B12 status biomarkers, e.g. methylmalonic acid, holotranscobalamin and serum vitamin B12, and brain volumes. Fully adjusted regression models showed a borderline significant association between plasma homocysteine and total brain volume, with a stronger association in the group that received B-vitamin supplementation. Serum B12 and holotranscobalamin were not associated with brain volumes, whereas high methylmalonic acid levels were associated with lower brain volumes in the group that received B-vitamins. In contrast, higher folate levels were associated with lower total brain volumes. In addition, when comparing the group that received two years of B-vitamin supplementation and those who did not, we observed lower brain volumes in the B-vitamin group, which might be a result of a difference in age between the two groups.
To conclude, the nutritional intervention studies showed little evidence for a beneficial effect on cognitive performance in relatively healthy older adults. Given the large problem of dementia, research on modifiable risk factors, including nutrition, should continue, with well thought out research methods, including large and long-term observational and intervention studies with high-sensitive study populations and early biomarkers (e.g. imaging techniques) for cognitive decline in combination with neuropsychological tests. In this way, nutrition can be added to the list of lifestyle factors that can fight dementia.
Voeding en beweging ter preventie van cognitieve achteruitgang
Severs, A. ; Rest, O. van de; Groot, C.P.G.M. de; Loon, L.J.C. van - \ 2014
VoedingsMagazine 27 (2014)1. - ISSN 0922-8012 - p. 18 - 20.
ouderen - ouderenvoeding - eiwittoevoegingen - dementie - kenvermogen - lichaamsbeweging - voeding en gezondheid - voedingsstoffen - elderly - elderly nutrition - protein supplements - dementia - cognition - exercise - nutrition and health - nutrients
Dementie wordt een steeds groter en kostbaarder probleem door de vergrijzing. Wetenschappers zijn naarstig op zoek naar mogelijkheden om het tij te keren. Zo ook dr.ir. Ondine van de Rest, onderzoeker aan Wageningen University. Haar onderzoek is gericht op de rol van voeding bij leeftijdsgerelateerde cognitieve achteruitgang. Samen met prof. dr.Lisette de Groot, hoogleraar voeding voor de oudere mens aan Wageningen Universiteit, en Prof. Dr. Luc van Loon, hoogleraar fysiologie van inspanning aan Maastricht Universiteit, voerde ze binnen het Top Instituut Food and Nutrition (TIFN) een interventiestudie uit bij ouderen naar het effect van eiwitsuppletie en beweging op de cognitie.
Facilitation of computer-supported collaborative learning in mixed- versus same-culture dyads: Does a collaboration script help?
Popov, V. ; Biemans, H.J.A. ; Brinkman, B. ; Kuznetsov, A.N. ; Mulder, M. - \ 2013
The Internet and Higher Education 19 (2013). - ISSN 1096-7516 - p. 36 - 48.
external scripts - argumentation - performance - environments - cognition - students - quality - context
To foster collaboration and improve the quality of students' discussions in mixed- and same- culture learner groups engaged in computer-supported collaborative learning (CSCL), a collaboration script was introduced. A 2 × 2-factorial design was used to examine the effects of using this collaboration script on students' online collaborative behavior and the quality of their discussions. A total of 130 university students worked in dyads on a topic concerned with intercultural communication. Culturally mixed dyads working with the script showed a higher frequency of seeking input and social interaction than the students in the other three types of dyads. Same-culture dyads working with the script showed a lower frequency of planning activity than same-culture dyads working without the script. Independent of script condition, the same-culture dyads displayed a higher frequency of contributing activity and showed a higher quality of online discussion than the mixed-culture dyads. Collaboration in culturally mixed groups is less than optimal and may require extra facilitation.
Bones, brains and B-vitamins : the impact of vitamin B12, folate and homocysteine on bone health and cognitive function in elderly
Wijngaarden, J.P. van - \ 2013
Wageningen University. Promotor(en): Lisette de Groot, co-promotor(en): Rosalie Dhonukshe-Rutten. - Wageningen : Wageningen UR - ISBN 9789461737151 - 192
botontkalking - kenvermogen - ouderen - beenderen - vitamine b12 - foliumzuur - homocysteïne - vitaminetoevoegingen - botbreuken - voedingstoestand - osteoporosis - cognition - elderly - bones - vitamin b12 - folic acid - homocysteine - vitamin supplements - bone fractures - nutritional state
An elevated homocysteine level has been indicated as a risk factor for cardiovascular disease, cognitive decline, and fractures. Supplementation of vitamin B12 and folic acid in order to normalize homocysteine levels might be of substantial public health importance as this might reduce the risk for several age-related conditions. This thesis focuses on two health outcomes frequently associated with elevated homocysteine levels and low levels of vitamin B12 and folate: osteoporosis and cognitive decline later in life.
Findings are presented in the context of a model which links dietary intake to biomarkers of nutritional status and subsequently to health outcomes. Two systematic reviews with meta-analyses investigated the current status of knowledge about the association of vitamin B12 intake and status with cognitive function, and the association of homocysteine, vitamin B12 and folate status with bone health. Baseline data of the B-PROOF study were used to assess 1) the association of vitamin B12 intake with status according to four biomarkers (vitamin B12, holotranscobalamin (holoTC), methylmalonic acid (MMA) and homocysteine), 2) the mutual association among these four vitamin B12 biomarkers and 3) the association between homocysteine, vitamin B12 biomarkers, folate and cognitive function. The effect of 2-year daily vitamin B12 (500 μg) and folic acid (400 μg) supplementation on fracture risk was assessed in the B-PROOF study, a large (N=2919) randomized controlled trial in elderly people (aged ≥65 years) with an elevated homocysteine level (≥12.0 µmol/L).
The systematic review of the literature showed no or inconsistent associations of vitamin B12 intake with cognitive function. Furthermore, serum vitamin B12 was not associated with risk of dementia, global cognition or memory. Studies on MMA and holoTC reported significant associations with risk of dementia, Alzheimer’s disease and global cognition. A meta-analysis showed that serum/plasma vitamin B12 per 50 pmol/L was borderline significantly associated with a lower fracture risk (RR=0.96, 95% CI = 0.92-1.00) and that homocysteine was significantly associated with a higher fracture risk (RR=1.04, 95% CI = 1.02-1.07). Meta-analyses regarding vitamin B12, folate and homocysteine levels and BMD did not show significant associations.
In the B-PROOF study a doubling of vitamin B12 intake was associated with 9% higher levels of vitamin B12, 15% higher holoTC, 9% lower MMA and 2% lower homocysteine, saturation of biomarkers occurs with dietary intakes of >5 μg B12. Levels of MMA and homocysteine were higher when vitamin B12 levels were below 330 pmol/L and when holoTC levels were below 100 pmol/L, with a steep elevation when levels of vitamin B12 and HoloTC were below 220 and 50 pmol/L respectively. At baseline, levels of vitamin B12 and holoTC were not associated with cognitive function in any cognitive domain. Levels of homocysteine (β= -0.009), folate (β= 0.002), MMA (β= -0.163) and the wellness score – a vitamin B12 biomarker combination score - (β= 0.048) were significantly associated with the domain of episodic memory. Additionally, homocysteine (β= -0.015) and the wellness score (β= 0.103) were significantly associated with the domain information processing speed.
The B-PROOF intervention did not lower the risk of fracture in the total population (HR=0.84, 95% CI = 0.58-1.22). Per protocol subgroup analysis of elderly aged >80 years, showed a lower risk of fracture in the intervention group (HR=0.28, 95% CI 0.10-0.74). We observed more cancer cases in the intervention group (HR=1.55, 95% CI = 1.04-2.30) compared to the placebo group. We cannot rule out the possibility of accelerated cancer progression as a possible negative side effect.
Our literature reviews and observational data confirm an association of levels of homocysteine, vitamin B12 and folate with cognitive function and fracture risk in elderly. Supplementation with vitamin B12 and folic acid did not lower the risk of fracture in the total study population. Though positive effects on fracture incidence emerged in elderly aged >80 years, these benefits should be weighed against potential risks.
Avoidance orientation moderates the effect of threatening messages
Riet, J.P. van 't; Ruiter, R.A.C. ; Vries, H. de - \ 2012
Journal of Health Psychology 17 (2012)1. - ISSN 1359-1053 - p. 14 - 25.
protection motivation theory - fear appeals - individual-differences - behavioral activation - college-students - planned behavior - health messages - metaanalysis - responses - cognition
This study investigated the influence of individual differences in people's dispositional avoidance orientation on the persuasive effects of low- and high-threat messages promoting moderate drinking. First, participents (N = 99) individual differences in avoidance orientation were assessed, after which they were provided with either high- or low-threat messages about the consequences of drinking too much alcohol. The primary outcome measures were information acceptance, attitude and intention. Results showed that participants low in avoidance orientation were more likely to be persuaded by the low-threat message, whereas participants high in avoidance orientation were more likely to be persuaded by the high-threat message.
Worms under cover: relationships between performance in learning tasks and personality in great tits (Parus major)
Amy, M. ; Oers, K. van; Naguib, M. - \ 2012
Animal Cognition 15 (2012)5. - ISSN 1435-9448 - p. 763 - 770.
risk-taking behavior - avian personalities - individual-differences - realized heritability - social information - evolution - cognition - traits - stress - prey
In animals, individual differences in learning ability are common and are in part explained by genetic differences, developmental conditions and by general experience. Yet, not all variations in learning are well understood. Individual differences in learning may be associated with elementary individual characteristics that are consistent across situations and over time, commonly referred to as personality or temperament. Here, we tested whether or not male great tits (Parus major) from two selection lines for fast or slow exploratory behaviour, an operational measure for avian personality, vary in their learning performance in two related consecutive tasks. In the first task, birds had to associate a colour with a reward whereas in the second task, they had to associate a new colour with a reward ignoring the previously rewarded colour. Slow explorers had shorter latencies to approach the experimental device compared with fast explorers in both tasks, but birds from the two selection lines did not differ in accomplishing the first task, that is, to associate a colour with a reward. However, in the second task, fast explorers had longer latencies to solve the trials than slow explorers. Moreover, relative to the number of trials needed to reach the learning criteria in the first task, birds from the slow selection line took more trials to associate a new colour with a reward while ignoring the previously learned association compared with birds from the fast selection line. Overall, the experiments suggest that personality in great tits is not strongly related to learning per se in such an association task, but that birds from different selection lines might express different learning strategies as birds from the different selection lines were differently affected by their previous learning performance.
Effects of ¿9-Tetrahydrocannabinol on human working memory function
Bossong, M.G. ; Jansma, J.M. ; Hell, H.H. van; Jager, G. ; Oudman, E. ; Saliasi, E. ; Kahn, R.S. ; Ramsey, N.F. - \ 2012
Biological Psychiatry 71 (2012)8. - ISSN 0006-3223 - p. 693 - 699.
dorsolateral prefrontal cortex - catechol-o-methyltransferase - endogenous cannabinoids - genetic-variation - brain-function - schizophrenia - dysfunction - fmri - mri - cognition
Background Evidence indicates involvement of the endocannabinoid (eCB) system in both the pathophysiology of schizophrenia and working memory (WM) function. Additionally, schizophrenia patients exhibit relatively strong WM deficits. These findings suggest the possibility that the eCB system is also involved in WM deficits in schizophrenia. In the present study, we examined if perturbation of the eCB system can induce abnormal WM activity in healthy subjects. Methods A pharmacological functional magnetic resonance imaging study was conducted with a placebo-controlled, cross-over design, investigating effects of the eCB agonist ¿9-tetrahydrocannabinol on WM function in 17 healthy volunteers, by means of a parametric Sternberg item-recognition paradigm with five difficulty levels. Results Performance accuracy was significantly reduced after ¿9-tetrahydrocannabinol. In the placebo condition, brain activity increased linearly with rising WM load. ¿9-Tetrahydrocannabinol administration enhanced activity for low WM loads and reduced the linear relationship between WM load and activity in the WM system as a whole and in left dorsolateral prefrontal cortex, inferior temporal gyrus, inferior parietal gyrus, and cerebellum in particular. Conclusions ¿9-Tetrahydrocannabinol enhanced WM activity network-wide for low loads, while reducing the load-dependent response for increasing WM loads. These results indicate that a challenged eCB system can induce both abnormal WM activity and WM performance deficits and provide an argument for the possibility of eCB involvement in WM deficits in schizophrenia