Addressing Overnutrition in Nursing Home Residents: A Community-Based, Multi-Component Cluster Randomized Controlled Trial to Enhance Nutrition and Physical Activity

The older population is growing, with increased longevity and a rising prevalence of overnu-trition among older adults. While life expectancy is increasing, so too are disability rates, especially among nursing home residents. Addressing overnutrition (overweight and obesi-ty) is crucial for preventing diseases, though current nutritional care practices might not be managing it effectively and could potentially worsen health conditions.

This study aims to maintain or increase physical function and care-related quality of life among older nursing home residents through a targeted nutritional and physical activity in-tervention. The specific study objectives are: 1) to characterize older adults in community care with overnutrition using a proposed screening model that integrates body mass index (≥ 25 kg/m²), muscle function, and non-communicable disease status, 2) to explore the underly-ing factors influencing dietary choices among nursing home residents, addressing the ques-tion "Why do nursing home residents eat what they do?", and 3) to develop and evaluate the impact of a multi-component intervention combining nutrition and physical activity on muscle function and quality of life in older adults with overnutrition.

A triangulated research design was used, including a cross-sectional study, an ethnographic fieldwork study, and a cluster randomized controlled trial (cRCT). The project was conduct-ed in six Danish nursing homes.
In the cross-sectional study (Paper I), medical records were used to collect data on partici-pants regarding age, sex, body composition, diseases, muscle strength, nutritional risk, and dietary intake. A covariate analysis and a Fisher's exact test were used to evaluate the differ-ences in the variables and in nutritional risk, malnutrition, and sarcopenia between the groups.
To better understand the factors affecting dietary habits, an ethnographic fieldwork (Paper II) using a 'foodscape' approach was conducted, involving approximately 2,000 hours of ob-servations, nine narrative interviews, and four group interviews with care staff. The induc-tive methods of grounded theory were used to analyze, conceptualize, and illustrate a food-scape.
The findings from both the cross-sectional and ethnographic studies informed the design of the cRCT (Paper III). This study included six months of intervention development followed by six months of intervention. The participating nursing homes were randomly divided into control (usual care) and intervention groups, with three units in each cluster. The interven-tion group, which included three nursing home units, worked collaboratively with residents and stakeholders to implement several components, such as protein-rich bread, a “Snack-on-Wheels” service, daily rehabilitation, and both physical and social activities, along with standardized communication and documentation practices. Muscle function was measured via hand grip strength and a 30-second chair stand test. The Adult Social Care Outcomes Toolkit (ASCOT) was used to assess care-related quality of life. The mixed methods were used to evaluate changes in muscle strength and quality of life.

The cross-sectional study revealed that the prevalence of overnutrition was 52% among the 116 participants in six NHs. Nearly 90% of participants with overnutrition exhibited low physical function and suffered from non-communicable diseases. Additionally, 87% were classified as malnourished, and 52% were identified as having sarcopenia (Paper I). In the ethnographic study, we found that the residents' nutritional intake was mainly determined by the municipal dietary concept, which provided three main meals and up to three snacks daily (Paper II). The study also underlined how the environment and staff focus also impacted the nutritional intake, with many snacks being high in fat and sugar while lacking protein, fiber, and micronutrients (Paper II). These findings informed the nutritional and physical activity intervention that was developed successfully through collaboration between residents, care staff, and other stakeholders. A total of 93 participants were included in the cRCT at base-line, and the findings showed that the intervention group improved muscle strength in male participants regardless of body weight, and participants with normal weight improved their quality of life, while this was maintained in those with overnutrition.

This PhD project shows that a targeted intervention combining nutrition and physical activi-ty can improve physical function and quality of life for overnourished older adults in nurs-ing homes. By addressing nutritional conditions such as malnutrition and sarcopenia, the research emphasizes the need for tailored approaches to enhance nutritional care. These findings support the integration of participatory methods into routine care to better address the complex needs of older nursing home residents with overnutrition.