TY - JOUR
T1 - Thyroid status and 6-year mortality in elderly people living in a mildly iodine-deficient area
T2 - The aging in the Chianti area study
AU - Ceresini, Graziano
AU - Ceda, Gian Paolo
AU - Lauretani, Fulvio
AU - Maggio, Marcello
AU - Usberti, Elisa
AU - Marina, Michela
AU - Bandinelli, Stefania
AU - Guralnik, Jack M.
AU - Valenti, Giorgio
AU - Ferrucci, Luigi
PY - 2013/6
Y1 - 2013/6
N2 - Objectives To test the hypothesis that, in older adults, living in a mildly iodine-deficient area, thyroid dysfunction may be associated with mortality independent of potential confounders. Design Longitudinal. Setting Community-based. Participants Nine hundred fifty-one individuals aged 65 and older. Measurements Plasma thyrotropin, free thyroxine, and free triiodothyronine concentrations and demographic features were evaluated in participants of the Invecchiare in Chianti Study aged 65 and older. Participants were classified according to thyroid function test. Kaplan-Meier survival and Cox proportional hazards models adjusted for confounders were used in the analysis. Results Eight hundred nineteen participants were euthyroid, 83 had subclinical hyperthyroidism (SHyper), and 29 had subclinical hypothyroidism (SHypo). Overt hypo- and hyperthyroidism were found in five and 15 subjects, respectively. During a median of 6 years of follow-up, 210 deaths occurred (22.1%), 98 (46.6%) of which were from cardiovascular causes. Kaplan-Meier analysis revealed higher overall mortality for SHyper (P =.04) than euthyroid subjects. After adjusting for multiple confounders, participants with SHyper (hazard ratio (HR) = 1.65, 95% confidence interval (CI) = 1.02-2.69) had significantly higher all-cause mortality than those with normal thyroid function. No significant association was found between SHyper and cardiovascular mortality. In euthyroid subjects, thyrotropin was found to be predictive of lower risk of all-cause mortality (HR = 0.76, 95% CI = 0.57-0.99). Conclusion SHyper is an independent risk factor for all-cause mortality in older adults. Low to normal circulating thyrotropin should be carefully monitored in elderly euthyroid individuals.
AB - Objectives To test the hypothesis that, in older adults, living in a mildly iodine-deficient area, thyroid dysfunction may be associated with mortality independent of potential confounders. Design Longitudinal. Setting Community-based. Participants Nine hundred fifty-one individuals aged 65 and older. Measurements Plasma thyrotropin, free thyroxine, and free triiodothyronine concentrations and demographic features were evaluated in participants of the Invecchiare in Chianti Study aged 65 and older. Participants were classified according to thyroid function test. Kaplan-Meier survival and Cox proportional hazards models adjusted for confounders were used in the analysis. Results Eight hundred nineteen participants were euthyroid, 83 had subclinical hyperthyroidism (SHyper), and 29 had subclinical hypothyroidism (SHypo). Overt hypo- and hyperthyroidism were found in five and 15 subjects, respectively. During a median of 6 years of follow-up, 210 deaths occurred (22.1%), 98 (46.6%) of which were from cardiovascular causes. Kaplan-Meier analysis revealed higher overall mortality for SHyper (P =.04) than euthyroid subjects. After adjusting for multiple confounders, participants with SHyper (hazard ratio (HR) = 1.65, 95% confidence interval (CI) = 1.02-2.69) had significantly higher all-cause mortality than those with normal thyroid function. No significant association was found between SHyper and cardiovascular mortality. In euthyroid subjects, thyrotropin was found to be predictive of lower risk of all-cause mortality (HR = 0.76, 95% CI = 0.57-0.99). Conclusion SHyper is an independent risk factor for all-cause mortality in older adults. Low to normal circulating thyrotropin should be carefully monitored in elderly euthyroid individuals.
KW - aging
KW - mortality
KW - subclinical hyperthyroidism
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U2 - 10.1111/jgs.12267
DO - 10.1111/jgs.12267
M3 - Article
C2 - 23647402
AN - SCOPUS:84879183423
SN - 0002-8614
VL - 61
SP - 868
EP - 874
JO - Journal of the American Geriatrics Society
JF - Journal of the American Geriatrics Society
IS - 6
ER -