Evaluating involuntary weight loss in older adults.

Involuntary weight loss is a common complaint among patients over 40 years of age. Few studies concerning the etiologies of weight loss, however, have been published. This article reviews two recent studies that address common causes of unintentional weight loss. In these investigations, almost half of the patients claiming significant weight loss had no decrease in weight at all. In 35 percent of patients with true weight loss, no physical source was found after six months of follow-up. Of those in whom a cause of weight loss was discovered, the etiology was usually apparent after a brief history, physical exam and screening laboratory evaluation. Common causes of involuntary weight loss are discussed. Guidelines for evaluation of the patient who complains of weight loss are offered.