Poor nutritional status is associated with fatigue in nursing home residents: a sub-group analysis from the incur study

Background: Fatigue is a symptom frequently complained by older people, leading to the inability to continue functioning at the normal level of activity. Fatigue may be reported as “lack of energy”. Despite the unclear physio-pathological mechanisms underlying fatigue, nutritional status may represents one of the most promising way to understand it. Objectives: The aim of this study was to investigate whether lack of energy was associated with nutritional status in nursing-home (NH) residents. Methods: We performed a cross-sectional analysis of the INCUR study cohort. Lack of energy was measured at baseline as part of the 10-items Geriatric Depression Scale. Nutritional status was evaluated according to Mini Nutritional Assessment Short-Form (MNASF). A 36-items frailty index (FI) was computed. Logistic regression models were performed to test the association of lack of energy with nutritional status. Results: A total of 573 NH residents were available for analysis. The median age (IQR) was 88 (83-91) years, with 411 (71.7%) females. At baseline, median MNA-SF (IQR) was 11 (9-12) with 71 (12.4%) patients that were malnourished. Among the patients included 42.9% (246 patients) reported lack of energy. At univariate logistic regression analysis MNA was inversely associated with lack of energy. At multivariate logistic regression analysis, adjusted for age, sex nursing home years and FI, we found that MNA was independently inversely associated with lack of energy (OR 0.88, 95% CI 0.81-0.96). Being malnourished is independently associated with lack of energy (OR 2.10, 95% CI 1.22-3.63). Among MNA components we found that Item A (decrease in food intake), Item C (reduced motricity) and Item D (psychophysical stress) were inversely associated with lack of energy (OR 0.54, 95% CI 0.37-0.80; OR 0.69, 95% CI 0.53-0.89; OR 0.48 95% CI 0.31-0.74; for each point respectively), independently each one and from the other confounders. Conclusion: In a cohort of very old NH residents, we found that an impaired nutritional status is associated with lack of energy. In particular, being malnourished bring a 2-fold risk of reporting lack of energy. More precisely, decrease in food intake, reduced motricity and psychophysical stress, each one were independently associated with lack of energy.