An optimal nutritional status contributes to healthy ageing. Conversely, ageing poses a nutritional risk as physiological, psychological, and social changes that may come with ageing influence appetite, food intake, and nutritional status. Undernutrition can be defined as “a state resulting from lack of intake or uptake of nutrition that leads to altered body composition (decreased fat free mass) and body cell mass leading to diminished physical and mental function and impaired clinical outcome from disease”. Although undernutrition is mostly prevalent among older adults living in long-term care facilities, in absolute numbers undernutrition is mostly encountered among older adults living in the community: 11 to 35% of community-dwelling older adults are affected. Undernutrition has unfavourable consequences for health, functioning, and quality of life. Therefore, prevention and early detection of nutritional risks are key for healthy ageing. Among many possible strategies and solutions that range from screening, prevention, and treatment, eHealth may be meaningful in signalling or preventing undernutrition at an early stage. The aim of this research was to provide insight into the feasibility and the effectiveness of a nutritional telemonitoring intervention for community-dwelling older adults. Chapters 2-6 present the results of this research and are summarised below.
The intervention consisted of self-measurements of nutritional outcomes and physical activity, nutrition education, and follow-up by a nurse. For this purpose, participants received measurement instruments (weighing scale, pedometer), and obtained an additional television channel and optionally a tablet computer to view their measurement results. The television channel was also used to display short messages concerning healthy eating and physical activity. Nurses received the results of the self-measurements and provided proper follow-up in case of nutritional risk. Although the intervention was practice-based, several theoretical strategies could be distinguished that underpinned the intervention, with the most important ones being self-monitoring, goalsetting, and feedback (Chapter 2).
This intervention was tested during a three-month pilot study (n=20) (Chapter 3). This study showed that the intervention could be implemented as intended by researchers and health care professionals. However, participants’ acceptance was low (only 50% was satisfied) and drop-out was high (n=9). Participants perceived the usability of the television channel as poor and needed more help than anticipated with the self-measurements. Based on these experiences, the intervention material was further developed with, among others, an improved television channel. The intervention was also made less intensive to further improve the fit with the target population.
Consequently, the intervention was evaluated during a six-month effect study (Chapter 4). Participants were allocated to the intervention group (n=97) or to the control group (n=107), based on municipality. Effect measurements were conducted at baseline, after 4.5 months, and at the end of the intervention and included measurements of diet quality, appetite, body weight, nutritional status, physical functioning, and quality of life. Participants at risk of undernutrition significantly improved their nutritional status (β (T1)=2.55, 95% CI (1.41, 3.68), β (T2)=1.77, 95% CI (0.60, 2.94)). Furthermore, intervention group participants increased scores for compliance with Dutch guidelines for the intake of vegetables (β=1.27, 95% CI (0.49, 2.05)), fruit (β=1.24, 95% CI (0.60, 1.88)), dietary fibre (β=1.13, 95% CI (0.70, 1.57)), protein (β=1.20, 95% CI (0.15, 2.24)), and physical activity (β=2.13, 95% CI (0.98, 3.29)). No effects on appetite, body weight, physical functioning, and quality of life were found.
Equally important as evaluating effectiveness, is investigating the feasibility and acceptability of an intervention. Therefore, a process evaluation was conducted in which a mixed method approach was used to study the process indicators reach, fidelity, dose, and acceptability (Chapter 5). A study of the reach of the intervention revealed that 80% of the participants completed the intervention and that participants who dropped out were older, had a worse cognitive and physical functioning, and were more care-dependent. With regard to fidelity, the intervention was implemented as intended. With regard to dose, participants’ adherence to self-measurements of weight was better than adherence to self-measurements via questionnaires, for which half of the participants needed help. Concerning acceptability, the intervention was well received by participants (satisfaction score 4.1 on a scale from 1-5), but satisfaction rates of nurses were lower with an average score of 3.5 (scale 1-5). Two constructs of acceptability predicted the intention to use the intervention: performance expectancy (β=0.40, 95% CI 0.13,0.67) and social influence (β=0.17, 95% CI 0.00,0.34). None of the process indicators were associated with intervention outcomes.
Besides studying process and effect outcomes, testing the theoretical framework of an intervention deepens understanding of how an intervention achieves its effects, thereby contributing to future intervention development. For this purpose, measurements were conducted of compliance to the behaviour change techniques self-monitoring and goalsetting, and of the behavioural determinants perceived behavioural control, attitude, and knowledge. Mediation analyses were used to study the mechanisms of impact (Chapter 6). The intervention increased self-monitoring and improved knowledge and perceived behavioural control for physical activity. Increased self-monitoring mediated the intervention’s effect on diet quality, fruit intake, and saturated fatty acids intake. Improved knowledge mediated the effect on protein intake. Nevertheless, the role of the hypothesised mediators was limited.
Concluding, our multi-component nutritional eHealth intervention led to improved diet quality and physical activity levels, and improved nutritional status in older adults with risk of undernutrition. The intervention was feasible to implement and was accepted by participants. This suggests that eHealth plays a valuable role in nutrition screening, prevention, and treatment of nutritional issues in community-dwelling older adults. Nevertheless, some issues need to be addressed to facilitate sustainable and scalable implementation, such as usability, perceived benefits of the intervention, and acceptability by health care professionals. Future research can address these issues by employing user-centred design and a collaborative approach involving all relevant stakeholders from research, practice, policy, and business. Directions for future research include unravelling mechanisms of impact, identifying groups of older adults that benefit most from nutritional eHealth interventions, improving accessibility of eHealth for vulnerable groups, establishing long-term effects on functioning and quality of life, and assessing economic impact.