Anorexia, physical function, and incident disability among the frail elderly population: results from the ilSIRENTE study

Abstract

Objective: Increasing evidence suggests that anorexia of aging can cause physical and mental impairment. The aim of the present study was to evaluate the relationship between anorexia of aging and measures of physical performance, muscle strength, and functional status in older persons aged 80 years or older.

Methods: Data are from baseline evaluation of 364 subjects enrolled in the ilSIRENTE study. The ilSIRENTE study is a prospective cohort study performed in the mountain community living in the Sirente geographic area (L'Aquila, Abruzzo) in central Italy. Physical performance was assessed using the physical performance battery score (SPPB), which is based on 3 timed tests: 4-meter walking speed, balance, and chair stand tests. Muscle strength was measured by hand grip strength. We defined anorexia as the presence of loss of appetite and/or lower food intake. Analyses of covariance were performed to evaluate the relationship of anorexia with physical function.

Results: In the unadjusted model, all the physical performance, muscle strength, and functional measures showed significant associations with the presence of anorexia. After adjustment for potential confounders (age, gender, BMI, number of diseases, depression, congestive heart failure, lung diseases) these associations were weaker but still statistically significant (physical performance battery score: subjects without anorexia 6.8, SE 0.2, subjects with anorexia 5.8, SE 0.4, P = .03; 4-meter walking speed: subjects without anorexia 0.5 m/s, SE 0.1, subjects with anorexia 0.3 m/s, SE 0.1, P = 5.001 hand grip strength: subjects without anorexia 30.8 kg, SE 0.7, subjects with anorexia 27.9 kg, SE 1.5, P = .03). Furthermore, relative to participants without anorexia, those subjects with anorexia showed a significantly higher risk of developing disability after 2 years of follow-up (hazard ratio 2.25; 95% confidence intervals 1.15-4.39).

Conclusions: Anorexia is common among community older subjects in Italy. Our results suggest that among old-old subjects, the presence of anorexia is associated with impaired physical performance and with a significant increased risk of incident disability, irrespective of potential confounders.