TY - JOUR

T1 - Thyroid Status and Mortality Risk in Older Adults With Normal Thyrotropin

T2 - Sex Differences in the Milan Geriatrics 75+ Cohort Study

AU - Ogliari, Giulia

AU - Smit, Roelof A J

AU - van der Spoel, Evie

AU - Mari, Daniela

AU - Torresani, Erminio

AU - Felicetta, Irene

AU - Lucchi, Tiziano A

AU - Rossi, Paolo D

AU - van Heemst, Diana

AU - de Craen, Anton J M

AU - Westendorp, Rudi G J

N1 - © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

PY - 2016/7/2

Y1 - 2016/7/2

N2 - BACKGROUND: Thresholds of optimal thyroid status in old age are controversial. We investigated the longitudinal association between thyroid parameters and 10-year all-cause mortality risk in older outpatients with normal thyrotropin (TSH) and modification by sex and age.METHODS: Baseline TSH, free thyroxine (fT4), and free triiodothyronine (fT3) were assessed in the Milan Geriatrics 75+ Cohort Study. 324 men and 609 women older than 75 years had normal TSH. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated for the associations between thyroid parameters and mortality risk using Cox regression. Sex-stratified analyses were adjusted for sociodemographic factors and comorbidities.RESULTS: 233 men and 367 women died during follow-up. After adjustment, each 1-mU/L higher TSH was associated with decreased mortality risk in men (HR 0.83, 95% CI 0.69-0.98), but not in women (HR 1.09, 95% CI 0.95-1.24) (p for sex interaction = .006). Each 1-ng/L higher fT4 was associated with increased mortality risk in men (HR 1.11, 95% CI 1.02-1.22), but not in women (HR 0.98, 95% CI 0.93-1.04) (p for sex interaction = .013). Each 1-pg/mL higher fT3 was associated with decreased mortality risk in women (HR 0.77, 95% CI 0.60-0.98), but not in men (HR 0.80, 95% CI 0.57-1.13). The inverse association between TSH and mortality was most pronounced in men older than 85 years.CONCLUSIONS: Among older outpatients with normal TSH, higher TSH and lower fT4 were associated with decreased mortality risk in men but not in women. When assessing thyroid status, sex and age should be taken into account.

AB - BACKGROUND: Thresholds of optimal thyroid status in old age are controversial. We investigated the longitudinal association between thyroid parameters and 10-year all-cause mortality risk in older outpatients with normal thyrotropin (TSH) and modification by sex and age.METHODS: Baseline TSH, free thyroxine (fT4), and free triiodothyronine (fT3) were assessed in the Milan Geriatrics 75+ Cohort Study. 324 men and 609 women older than 75 years had normal TSH. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated for the associations between thyroid parameters and mortality risk using Cox regression. Sex-stratified analyses were adjusted for sociodemographic factors and comorbidities.RESULTS: 233 men and 367 women died during follow-up. After adjustment, each 1-mU/L higher TSH was associated with decreased mortality risk in men (HR 0.83, 95% CI 0.69-0.98), but not in women (HR 1.09, 95% CI 0.95-1.24) (p for sex interaction = .006). Each 1-ng/L higher fT4 was associated with increased mortality risk in men (HR 1.11, 95% CI 1.02-1.22), but not in women (HR 0.98, 95% CI 0.93-1.04) (p for sex interaction = .013). Each 1-pg/mL higher fT3 was associated with decreased mortality risk in women (HR 0.77, 95% CI 0.60-0.98), but not in men (HR 0.80, 95% CI 0.57-1.13). The inverse association between TSH and mortality was most pronounced in men older than 85 years.CONCLUSIONS: Among older outpatients with normal TSH, higher TSH and lower fT4 were associated with decreased mortality risk in men but not in women. When assessing thyroid status, sex and age should be taken into account.

U2 - 10.1093/gerona/glw113

DO - 10.1093/gerona/glw113

M3 - Journal article

C2 - 27371954

JO - Journals of Gerontology. Series A: Biological Sciences & Medical Sciences

JF - Journals of Gerontology. Series A: Biological Sciences & Medical Sciences

SN - 1079-5006

ER -