Evaluation of muscle-skeletal strength and Peak-Expiratory-Flow in severely malnourished inpatients with anorexia nervosa: a pilot study

OBJECTIVES Anorexia nervosa is a complex psychiatric disorder that can lead to specific somatic complications. Malnutrition is frequent and can involve a decrease of mobility, up to functional impotence, in individuals with extremely severe cases. The aim of this pilot study was to examine muscle strength and peak expiratory flow (PEF) in severely undernourished patients with anorexia nervosa at admission and after 5 wk of renutrition by tube feeding, and to find the clinical and biological correlates of muscle-strength impairment. METHODS A prospective observational study was conducted over 6 mo. Manual muscle testing, measures of PEF, and clinical and biologic assessments were performed at baseline and after 5 wk of renutrition. RESULTS Twenty-three extremely malnourished female participants (mean body mass index: 11.4 ± 1.3 kg/m2) were included. All participants had global impairment in muscle strength (manual muscle testing: 37.7 ± 7.7) and PEF (253.3 ± 60 mL/min) at admission. Muscle weakness was higher in axial than peripheral muscle groups (P 0.05). Muscle strength at admission was significantly associated with severity of undernourishment (body mass index and albumin) and transaminitis (P < 0.05). At follow-up, musculoskeletal strength and PEF were significantly improved after partial weight recovery (P < 0.01). CONCLUSIONS Extremely undernourished people with anorexia nervosa present a decrease of PEF and musculoskeletal strength predominant on axial muscles. Both are associated with severity of malnutrition and liver damage. Partial recovery was observed after 5 wk of enteral nutrition.