Subclinical hypothyroidism, weight change, and body composition in the elderly: the Cardiovascular Health Study
Margaret C Garin1, Alice M Arnold, Jennifer S Lee
1Division of Endocrinology, Diabetes, and Metabolism (M.C.G., A.R.C.), Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104; Department of Biostatistics (A.M.A.), University of Washington, Seattle, Washington 98155; Division of Endocrinology, Gerontology, and Metabolism (J.S.L.), Stanford University School of Medicine and Veterans Administration Palo Alto Health Care System, Palo Alto, California 94305; and Departments of Pathology and Biochemistry (R.P.T.), University of Vermont, Burlington, Vermont 05405.
Background:
Subclinical hypothyroidism is common in the elderly, yet its relationship with weight and body composition is unclear.
Objective:
We examined the relationship between subclinical hypothyroidism and weight change and body composition in older adults.
Methods:
A total of 427 subclinically hypothyroid and 2864 euthyroid U.S. individuals ≥65 years old enrolled in the Cardiovascular Health Study and not taking thyroid preparations were included. Analyses of 6-year weight change were performed, compared by thyroid status. A cross-sectional analysis of thyroid status and body composition was performed in a subset of 1276 participants who had dual-energy x-ray absorptiometry scans. Models were risk factor-adjusted and stratified by sex.
Results:
Overall, participants lost weight during follow-up (-0.38 kg/y in men, -0.37 kg/y in women). Subclinical hypothyroidism, when assessed at a single time point or persisting over 2 years, was not associated with a difference in weight change compared with euthyroidism. Subclinical hypothyroidism was also not associated with differences in lean mass, fat mass, or percent fat compared with euthyroidism. A TSH level 1 mU/L higher within the euthyroid or subclinical hypothyroid range was associated with a 0.51-kg higher baseline weight in women only (P < .001) but not with weight change in either sex. A 1 ng/dL higher free T4 level was associated with lower baseline weight and 0.32 kg/y greater weight loss in women only (P = .003). Baseline weight and weight change did not differ by T3 levels.
Conclusions:
Our data do not support a clinically significant impact of subclinical hypothyroidism on weight status in the elderly.
Related Concept Videos
Hypothyroidism II: Pathophysiology
Hyperthyroidism II: Pathophysiology
Hyperthyroidism I: Introduction
Graves Disease II: Pathophysiology
Hypertension III: Clinical Manifestations and Diagnostic Studies
Pharmacodynamics in Geriatric Patients: Effects of Age
