Figure 1.

Flow diagram of NHANES participants included in the primary analysis. Treated hypothyroidism was defined as taking thyroid hormone and reporting a history of thyroid disease. Untreated subclinical hypothyroidism was defined as TSH level between 5.6 and 9.9 mIU/L with an FT4 ≥0.6 ng/dL. Untreated clinical hypothyroidism was defined as a TSH level >5.6 mIU/L and an FT4 <0.6 ng/mL, or a TSH level ≥10.0 mIU/L and any FT4 level. *One participant was pregnant and had a history of thyroid cancer. ^†Of 565 participants taking thyroid hormone, 29 did not report a history of thyroid disease. Abbreviations: FT4, free thyroxine; NHANES, National Health and Nutrition Examination Survey; TSH, thyroid-stimulating hormone.