Medical School, University of Western Australia, Perth, WA, Australia.
Clinical Biochemistry Department, PathWest Laboratory Medicine, Fiona Stanley Hospital, Perth, WA, Australia.
Clin Endocrinol (Oxf). 2024 Feb;100(2):170-180. doi: 10.1111/cen.14997. Epub 2023 Dec 7.
Prevalence of subclinical thyroid disease increases with age, but optimal detection and surveillance strategies remain unclear particularly for older men. We aimed to assess thyroid stimulating hormone (TSH) and free thyroxine (FT4) concentrations and their longitudinal changes, to determine the prevalence and incidence of subclinical thyroid dysfunction in older men.
DESIGN, PARTICIPANTS AND MEASUREMENTS: Longitudinal study of 994 community-dwelling men aged ≥70 years without known or current thyroid disease, with TSH and FT4 concentrations assessed at baseline and follow-up (after 8.7 ± 0.9 years). Factors associated with incident subclinical thyroid dysfunction were examined by logistic regression and receiver operating characteristic analyses.
At baseline, 85 men (8.6%) had subclinical hypothyroidism and 10 (1.0%) subclinical hyperthyroidism. Among 899 men euthyroid at baseline (mean age 75.0 ± 3.0 years), 713 (79.3%) remained euthyroid, 180 (20.0%) developed subclinical/overt hypothyroidism, and 6 (0.7%) subclinical/overt hyperthyroidism. Change in TSH correlated with baseline TSH (r = .16, p < .05). Change in FT4 correlated inversely with baseline FT4 (r = -0.35, p < .05). Only higher age and baseline TSH predicted progression from euthyroid to subclinical/overt hypothyroidism (fully-adjusted odds ratio [OR] per year=1.09, 95% confidence interval [CI] = 1.02-1.17, p = .006; per 2.7-fold increase in TSH OR = 65.4, CI = 31.9-134, p < .001). Baseline TSH concentration ≥2.34 mIU/L had 76% sensitivity and 77% specificity for predicting development of subclinical/overt hypothyroidism.
In older men TSH concentration increased over time, while FT4 concentration showed little change. Subclinical or overt hypothyroidism evolved in one fifth of initially euthyroid men, age and higher baseline TSH predicted this outcome. Increased surveillance for thyroid dysfunction may be justified in older men, especially those with high-normal TSH.
亚临床甲状腺疾病的患病率随年龄增长而增加，但最佳检测和监测策略仍不明确，尤其是对于老年男性。我们旨在评估甲状腺刺激激素（TSH）和游离甲状腺素（FT4）浓度及其纵向变化，以确定老年男性中亚临床甲状腺功能障碍的患病率和发病率。
设计、参与者和测量：对 994 名年龄≥70 岁、无已知或当前甲状腺疾病的社区居民进行纵向研究，在基线和随访时（8.7±0.9 年后）评估 TSH 和 FT4 浓度。通过逻辑回归和受试者工作特征分析检查与新发亚临床甲状腺功能障碍相关的因素。
在基线时，85 名男性（8.6%）患有亚临床甲状腺功能减退症，10 名（1.0%）患有亚临床甲状腺功能亢进症。在 899 名基线时甲状腺功能正常的男性（平均年龄 75.0±3.0 岁）中，713 名（79.3%）保持甲状腺功能正常，180 名（20.0%）发展为亚临床/显性甲状腺功能减退症，6 名（0.7%）发展为亚临床/显性甲状腺功能亢进症。TSH 的变化与基线 TSH 相关（r=0.16，p<0.05）。FT4 的变化与基线 FT4 呈负相关（r=-0.35，p<0.05）。只有较高的年龄和基线 TSH 预测从甲状腺功能正常向亚临床/显性甲状腺功能减退的进展（每年的调整后优势比[OR]为 1.09，95%置信区间[CI]为 1.02-1.17，p=0.006；TSH 增加 2.7 倍的 OR 为 65.4，CI 为 31.9-134，p<0.001）。基线 TSH 浓度≥2.34 mIU/L 对预测亚临床/显性甲状腺功能减退的发生具有 76%的敏感性和 77%的特异性。
在老年男性中，TSH 浓度随时间增加，而 FT4 浓度变化不大。最初甲状腺功能正常的男性中有五分之一发展为亚临床或显性甲状腺功能减退症，年龄和较高的基线 TSH 预测了这一结果。对于老年男性，特别是 TSH 处于高正常值的男性，可能需要增加对甲状腺功能障碍的监测。
