TY - JOUR
T1 - Thyroid hormones and mortality risk in euthyroid individuals
T2 - The Kangbuk Samsung health study
AU - Zhang, Yiyi
AU - Chang, Yoosoo
AU - Ryu, Seungho
AU - Cho, Juhee
AU - Lee, Won Young
AU - Rhee, Eun Jung
AU - Kwon, Min Jung
AU - Pastor-Barriuso, Roberto
AU - Rampal, Sanjay
AU - Han, Won Kon
AU - Shin, Hocheol
AU - Guallar, Eliseo
PY - 2014/7
Y1 - 2014/7
N2 - Context: Hyperthyroidism and hypothyroidism, both overt and subclinical, are associated with all-cause and cardiovascular mortality. The association between thyroid hormones and mortality in euthyroid individuals, however, is unclear. Objective: To examine the prospective association between thyroid hormones levels within normal ranges and mortality endpoints. Setting and Design: A prospective cohort study of 212 456 middle-aged South Korean men and women who had normal thyroid hormone levels and no history of thyroid disease at baseline from January 1, 2002 to December 31, 2009. Free T4 (FT4), free T3 (FT3), and TSH levels were measured by RIA. Vital status and cause of death ascertainment were based on linkage to the National Death Index death certificate records. Results: After a median follow-up of 4.3 years, 730 participants died (335 deaths from cancer and 112 cardiovascular-related deaths). FT4 was inversely associated with all-cause mortality (HR = 0.77, 95% confidence interval 0.63-0.95,comparingthe highest vs lowest quartile of FT4; P for linear trend = .01), and FT3 was inversely associated cancer mortality (HR = 0.62,95%confidence interval 0.45-0.85; P for linear trend = .001). TSH was not associated with mortality endpoints. Conclusions: In a large cohort of euthyroid men and women, FT4 and FT3 levels within the normal range were inversely associated with the risk of all-cause mortality and cancer mortality, particularly liver cancer mortality.
AB - Context: Hyperthyroidism and hypothyroidism, both overt and subclinical, are associated with all-cause and cardiovascular mortality. The association between thyroid hormones and mortality in euthyroid individuals, however, is unclear. Objective: To examine the prospective association between thyroid hormones levels within normal ranges and mortality endpoints. Setting and Design: A prospective cohort study of 212 456 middle-aged South Korean men and women who had normal thyroid hormone levels and no history of thyroid disease at baseline from January 1, 2002 to December 31, 2009. Free T4 (FT4), free T3 (FT3), and TSH levels were measured by RIA. Vital status and cause of death ascertainment were based on linkage to the National Death Index death certificate records. Results: After a median follow-up of 4.3 years, 730 participants died (335 deaths from cancer and 112 cardiovascular-related deaths). FT4 was inversely associated with all-cause mortality (HR = 0.77, 95% confidence interval 0.63-0.95,comparingthe highest vs lowest quartile of FT4; P for linear trend = .01), and FT3 was inversely associated cancer mortality (HR = 0.62,95%confidence interval 0.45-0.85; P for linear trend = .001). TSH was not associated with mortality endpoints. Conclusions: In a large cohort of euthyroid men and women, FT4 and FT3 levels within the normal range were inversely associated with the risk of all-cause mortality and cancer mortality, particularly liver cancer mortality.
UR - http://www.scopus.com/inward/record.url?scp=84904043191&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84904043191&partnerID=8YFLogxK
U2 - 10.1210/jc.2013-3832
DO - 10.1210/jc.2013-3832
M3 - Article
C2 - 24708095
AN - SCOPUS:84904043191
SN - 0021-972X
VL - 99
SP - 2467
EP - 2476
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
IS - 7
ER -