Muscles and Mortality

Several of the studies showing a relationship between muscle strength or mass and mortality:

1. Metter, Talbot, Schrager, and Conwit, "Skeletal Muscle Strength as a Predictor of All-Cause Mortality in Healthy Men," Journals of Gerontology Series A 57 (2002): B359-B365.

2. Newman et al., "Strength, but not Muscle Mass, Is Associated With Mortality in the Health, Aging and Body Composition Study Cohort," Journals of Gerontology Series A 61 (2006): 72-77.

3. Wannamethee et al., "Decreased Muscle and Increased Central Adiposity are Independently Related to Mortality in Older Men," American Journal of Clinical Nutrition 86 no. 5 (Nov. 2007): 1339-1346.

4. Marquis et al., "Midthigh Muscle Cross-Sectional Area Is a Better Predictor of Mortality than Body Mass Index in Patients with Chronic Obstructive Pulmonary Disease," American Journal of Respiratory and Critical Care Medicine 166 (2002): 809-13.

5. Mador, "Muscle Mass, Not Body Weight, Predicts Outcome in Patients with Chronic Obstructive Pulmonary Disease," American Journal of Respiratory and Critical Care Medicine 166 (2002): 787-89. A key passage:

Correlation, however, does not prove causation.Thus, we cannot say whether a reduction in muscle mass causes an increase in mortality or whether a reduction in muscle mass is merely a reflection of severity of disease. If a reduction in muscle mass is responsible for the increased mortality, then interventions that successfully increase muscle mass should lead to improvement in mortality. No study addressing this issue has been performed.