Title | The natural history of subclinical hypothyroidism in the elderly: the cardiovascular health study. |
Publication Type | Journal Article |
Year of Publication | 2012 |
Authors | Somwaru, LL, Rariy, CM, Arnold, AM, Cappola, AR |
Journal | J Clin Endocrinol Metab |
Volume | 97 |
Issue | 6 |
Pagination | 1962-9 |
Date Published | 2012 Jun |
ISSN | 1945-7197 |
Keywords | Age Distribution, Aged, Aged, 80 and over, Autoantibodies, Cardiovascular Diseases, Cohort Studies, Disease Progression, Female, Humans, Hypothyroidism, Iodide Peroxidase, Logistic Models, Longitudinal Studies, Male, Prevalence, Risk Factors, Seroepidemiologic Studies, Severity of Illness Index, Sex Distribution, Thyrotropin |
Abstract | <p><b>CONTEXT: </b>Studies of long-term outcomes of subclinical hypothyroidism have assessed only baseline thyroid function, despite natural transitions to euthyroidism and overt hypothyroidism over time.</p><p><b>OBJECTIVE: </b>We provide estimates of persistence, resolution, and progression of subclinical hypothyroidism over 4 yr, stratified by baseline TSH, anti-thyroid peroxidase antibody (TPOAb) status, age, and sex.</p><p><b>DESIGN, SETTING, AND PARTICIPANTS: </b>Participants were 3996 U.S. individuals at least 65 yr old enrolled in the Cardiovascular Health Study. Subclinical hypothyroidism was detected at baseline in 459 individuals not taking thyroid medication.</p><p><b>MAIN OUTCOME MEASURE: </b>Thyroid function was evaluated at 2 and 4 yr and initiation of thyroid medication annually. Results were stratified by baseline TSH, TPOAb status, age, and sex.</p><p><b>RESULTS: </b>Persistence of subclinical hypothyroidism was 56% at 2 and 4 yr. At 2 yr, resolution was more common with a TSH of 4.5-6.9 mU/liter (46 vs. 10% with TSH 7-9.9 mU/liter and 7% with TSH ≥10 mU/liter; P < 0.001) and with TPOAb negativity (48 vs. 15% for positive; P < 0.001). Higher TSH and TPOAb positivity were independently associated with lower likelihood of reversion to euthyroidism (P < 0.05). TSH of 10 mU/liter or higher was independently associated with progression to overt hypothyroidism (P < 0.05). Transitions between euthyroidism and subclinical hypothyroidism were common between 2 and 4 yr. Age and sex did not affect transitions.</p><p><b>CONCLUSIONS: </b>Subclinical hypothyroidism persists for 4 yr in just over half of older individuals, with high rates of reversion to euthyroidism in individuals with lower TSH concentrations and TPOAb negativity. Future studies should examine the impact of transitions in thyroid status on clinical outcomes.</p> |
DOI | 10.1210/jc.2011-3047 |
Alternate Journal | J. Clin. Endocrinol. Metab. |
PubMed ID | 22438233 |
PubMed Central ID | PMC3387427 |
Grant List | N01-HC-85085 / HC / NHLBI NIH HHS / United States R01 AG015928 / AG / NIA NIH HHS / United States U01 HL080295 / HL / NHLBI NIH HHS / United States N01-HC-85081 / HC / NHLBI NIH HHS / United States N01 HC015103 / HC / NHLBI NIH HHS / United States R56 AG020098 / AG / NIA NIH HHS / United States R01AG-032317 / AG / NIA NIH HHS / United States AG-20098 / AG / NIA NIH HHS / United States N01HC55222 / HL / NHLBI NIH HHS / United States N01-HC-85086 / HC / NHLBI NIH HHS / United States N01HC85086 / HL / NHLBI NIH HHS / United States AG-027058 / AG / NIA NIH HHS / United States N01-HC-85082 / HC / NHLBI NIH HHS / United States N01 HC-55222 / HC / NHLBI NIH HHS / United States T32 HL007609 / HL / NHLBI NIH HHS / United States N01-HC-85083 / HC / NHLBI NIH HHS / United States N01-HC-75150 / HC / NHLBI NIH HHS / United States N01-HC-85080 / HC / NHLBI NIH HHS / United States R01 HL080295 / HL / NHLBI NIH HHS / United States R01 AG020098 / AG / NIA NIH HHS / United States R01 AG032317 / AG / NIA NIH HHS / United States N01HC75150 / HL / NHLBI NIH HHS / United States N01-HC-85079 / HC / NHLBI NIH HHS / United States HL080295 / HL / NHLBI NIH HHS / United States N01-HC-85239 / HC / NHLBI NIH HHS / United States AG-023629 / AG / NIA NIH HHS / United States N01HC85079 / HL / NHLBI NIH HHS / United States R01 AG023629 / AG / NIA NIH HHS / United States R01 AG027058 / AG / NIA NIH HHS / United States N01 HC045133 / HC / NHLBI NIH HHS / United States N01 HC035129 / HC / NHLBI NIH HHS / United States R56 AG023629 / AG / NIA NIH HHS / United States N01-HC-85084 / HC / NHLBI NIH HHS / United States |