Samenvatting

Background: Frailty is considered highly prevalent in older age. Frailty causes a high risk of falls, disability, hospitalization, and mortality. This eventually might be the turning-point for older patients to shift from independent living to assisted living. Poor nutritional status might be an important reversible risk factor for frailty. Given nutritional status as risk factor and weakness in frailty, there might be a relation between protein intake and muscle strength. Data of the relation between protein intake and muscle strength among frail patients is scarce and show conflicting results. We aimed to assess the following research question: What is the relation between protein intake and muscle strength in frail elderly? Method: Primary measures were protein intake and muscle strength (handgrip strength and leg press). A correlation test was used to determine the correlation between protein intake and muscle strength. A multiple regression analysis was conducted to determine whether the relation between muscle strength and protein intake differ between men and women. The confounding factors were age, gender, lean body mass (DXA), energy intake and physical activity (counts/min). Results: A total of 62 subjects were included in this study (Mean ± SD; Age: 78 ± 7.6 years; hand grip strength: 26.7 ± 9.6 kg; leg press strength: 120.2 ± 32.1 kg; protein intake: 77 ± 22.1 g). The correlation analysis showed that there was a significant, weak positive correlation between protein intake and hand grip strength (r = .288; p = .025) and between protein intake and leg press strength (r = .303; p = .018). After adjusting for confounders, protein intake was not significantly associated with hand grip strength (p = .213) and leg press strength (p = .169). Separating men and women gave no different outcome in association between protein intake and muscle strength (p = .101). Conclusion: There is no association between protein intake and muscle strength in frail elderly above 65 years. More research is needed to determine the factors that provide an increase in muscle strength.