The Subjective Global Assessment reliably identifies malnutrition-related muscle dysfunction

Muscle dysfunction is a common finding in malnourished patients and is associated with poor outcome. We investigated whether the Subjective Global Assessment (SGA) is a valuable tool for identifying malnutrition-related muscle dysfunction.

Two hundred eighty seven consecutive patients were assessed on admission to hospital according to the SGA, anthropometric measurements, and to the results of bioelectrical impedance analysis. The SGA was used as the main criterion for the classification of malnutrition. Muscle function was assessed by handgrip strength.

Maximal voluntary handgrip strength was significantly lower in malnourished than in well-nourished male and female patients (45.22 (13.51-67.7)kg versus 30.82(11-48) kg in men; 23.81 (5.60-56.5) kg versus 18.5 (5.90-48.8) kg in women). Handgrip strength tended to decline with age. Handgrip strength was positively correlated to body cell mass (BCM) (r=0.72, P<0.001 in men and: r=0.56, P<0.001 in women) and to body mass index (r=0.271, P=0.03 in men and r=0.183, P=0.02 in women). BCM was identified as a powerful contributor to the variation in handgrip strength (delta r2=0.645, P<0.001).

The SGA appears to be a reliable bedside assessment tool for malnutrition and malnutrition-related dysfunction. Patients classified malnourished according to the SGA have an impaired functional status. Every effort should be made to provide both nutritional and physical therapy in order to improve the patients' outcome.