Hypothyroidism and Atherosclerosis

This autopsy finding of diffuse atherosclerosis in a 58-yrold woman was published as an appendix to William Ord’s classical description of the syndrome of myxedema. Soon thereafter, the hypothesis of a causal relationship between hypothyroidism and atherosclerosis was first raised in 1883 by E. Theodor Kocher (2), who noted that arteriosclerosis commonly occurred after thyroid extirpation. Since the time of the first associations between these two common disorders, hypothyroidism and atherosclerosis have subsequently been linked by a body of clinical case reports, epidemiological studies, and biochemical observations. The hypothesis of a relationship has subsequently been tested in case-control and cohort studies. Important associations have been identified among hypercholesterolemia, hypertension, and certain newer risk factors for atherosclerosis in individuals with overt hypothyroidism and, in some cases, subclinical hypothyroidism. There have also been clinical observations and trials describing the consequences of treating hypothyroidism in patients with ischemic heart disease and of revascularizing patients with ischemic heart disease who are hypothyroid. These studies are the subject of this commentary.