Background: Muscle weakness and structural changes in striated skeletal muscle are common in persons with chronic alcoholism.
Objective: The objective of the study was to assess the role of malnutrition in the development of chronic alcoholic myopathy.
Design: We prospectively evaluated 146 men who reported an intake >/=100 g ethanol/d for the previous 5 y and 73 well-nourished control subjects. Alcohol consumption, energy and protein nutritional status, and deltoid muscle strength were determined. Deltoid muscle tissue specimens were taken from alcoholics and from 14 control subjects for histochemical studies and morphometric measurements of the fibers.
Results: Deltoid muscle strength was less in alcoholics than in control subjects (P < 0.001). Muscle strength correlated with lifetime consumption of ethanol (r = -0.56, P < 0.001), and a decrease in muscle strength was significantly greater in the presence of energy malnutrition. Using logistic regression analysis, we observed that alcoholics with muscle strength < 18 kg had the independent risk factors of an arm muscle area < 50 cm(2) (odds ratio: 5.4; 95% CI: 2.3, 12.3), consumption of > 1600 kg ethanol throughout their lives (odds ratio: 4.5; 95% CI: 2.0, 10.1), and protein malnutrition (odds ratio: 4.2; 95% CI: 1.4, 12.7). Protein malnutrition was also associated with muscle inefficiency (P < 0.001). Histologic myopathy was present in 58% of alcoholics, was related to lifetime ethanol consumption (P = 0.001), and was more severe in the presence of protein malnutrition (P = 0.01).
Conclusion: Malnutrition is an additional developmental factor in the functional and structural muscle damage induced by chronic ethanol consumption.