Department of Endocrinology, Taizhou Central Hospital (Taizhou University Hospital), Taizhou, China.
Brain Behav. 2024 Sep;14(9):e70037. doi: 10.1002/brb3.70037.
Accumulating evidence suggests that thyroid dysfunction may be related to the risk of dementia. However, previous studies evaluating the association between subclinical hyperthyroidism and the risk of dementia showed inconsistent results. This systematic review and meta-analysis were performed to evaluate the relationship between subclinical hyperthyroidism and the incidence of dementia in the general population.
Cohort studies relevant were retrieved by searching the electronic databases including PubMed, Web of Science, and Embase. A random-effects model was used to combine the data by incorporating the influence of between-study heterogeneity. Subgroup and meta-regression analyses were performed to investigate the source of heterogeneity.
Nine cohort studies including 49,218 community-derived participants were included. Among them, 3177 (6.5%) had subclinical hyperthyroidism at baseline. During a mean follow-up of 10.2 years, 4044 participants developed dementia. The pooled results showed that compared to the participants with euthyroidism, those with subclinical hyperthyroidism had a higher incidence of dementia (risk ratio: 1.38, 95% confidence interval: 1.09 to 1.74, p = .006; I = 47%). Subgroup analyses according to study design, age of the participants, methods for diagnosis of dementia, or analytic model did not significantly change the results. The univariate meta-regression showed that the cutoff of thyroid-stimulating hormone for defining subclinical hyperthyroidism negatively affected the association between subclinical hyperthyroidism and dementia (coefficient: -1.44, p = .009), which completely explained the heterogeneity (residual I = 0%).
Subjects with subclinical hyperthyroidism may have a higher risk of dementia compared to those with euthyroidism.
越来越多的证据表明，甲状腺功能障碍可能与痴呆风险有关。然而，先前评估亚临床甲状腺功能亢进与痴呆风险之间关系的研究结果并不一致。本系统评价和荟萃分析旨在评估一般人群中亚临床甲状腺功能亢进与痴呆发生率之间的关系。
通过检索 PubMed、Web of Science 和 Embase 等电子数据库，检索相关的队列研究。采用随机效应模型，通过纳入研究间异质性的影响，对数据进行合并。进行亚组和荟萃回归分析，以探讨异质性的来源。
纳入了 9 项队列研究，共包含 49218 名社区人群。其中，3177 人（6.5%）在基线时患有亚临床甲状腺功能亢进。在平均 10.2 年的随访期间，有 4044 人发生痴呆。汇总结果显示，与甲状腺功能正常的参与者相比，亚临床甲状腺功能亢进的参与者痴呆发生率更高（风险比：1.38，95%置信区间：1.09 至 1.74，p = 0.006；I = 47%）。根据研究设计、参与者年龄、痴呆诊断方法或分析模型进行的亚组分析并未显著改变结果。单变量荟萃回归表明，定义亚临床甲状腺功能亢进的促甲状腺激素的切点会对亚临床甲状腺功能亢进与痴呆之间的关联产生负面影响（系数：-1.44，p = 0.009），这完全解释了异质性（残余 I = 0%）。
与甲状腺功能正常的参与者相比，亚临床甲状腺功能亢进的参与者可能具有更高的痴呆风险。
