The aging thyroid in health and disease

Abstract

The most consistent biochemical thyroid abnormality associated with age, various illnesses, and drugs is the low T3 syndrome due to decreased activity of 5'-deiodinase. Lower T3 levels may help reduce the catabolic effects of illness on the individual. The diagnosis of hypothyroidism can be missed in the elderly when its typical manifestations are attributed to aging. The diagnosis of hyperthyroidism in the elderly may likewise be difficult because of atypical clinical presentations. A high index of clinical suspicion should lead to a timely diagnosis of these eminently treatable disorders.