Thyroid function and the risk of dementia The Rotterdam Study
- 17 October 2016
- journal article
- research article
- Published by Ovid Technologies (Wolters Kluwer Health) in Neurology
- Vol. 87 (16), 1688-1695
- https://doi.org/10.1212/WNL.0000000000003227
Abstract
Objective: To study the role of thyroid function in dementia, cognitive function, and subclinical vascular brain disease with MRI. Methods: Analyses were performed within the Rotterdam Study (baseline 1997), a prospective, population-based cohort. We evaluated the association of thyroid-stimulating hormone (TSH) and free thyroxine with incident dementia using Cox models adjusted for age, sex, cardiovascular risk factors, and education. Absolute risks were calculated accounting for death as a competing risk factor. Associations of thyroid function with cognitive test scores and subclinical vascular brain disease (white matter lesions, lacunes, and microbleeds) were assessed with linear or logistic regression. Additionally, we stratified by sex and restricted analyses to normal thyroid function. Results: We included 9,446 participants with a mean age of 65 years. During follow-up (mean 8.0 years), 601 participants had developed dementia. Higher TSH was associated with lower dementia risk in both the full and normal ranges of thyroid function (hazard ratio [HR] 0.90, 95% confidence interval [CI] 0.83-0.98; and HR 0.76, 95% CI 0.64-0.91, respectively). This association was independent of cardiovascular risk factors. Dementia risk was higher in individuals with higher free thyroxine (HR 1.04, 95% CI 1.01-1.07). Absolute 10-year dementia risk decreased from 15% to 10% with higher TSH in older women. Higher TSH was associated with better global cognitive scores (p = 0.021). Thyroid function was not related to subclinical vascular brain disease as indicated by MRI. Conclusions: High and high-normal thyroid function is associated with increased dementia risk. Thyroid function is not related to vascular brain disease as assessed by MRI, suggesting a role for thyroid hormone in nonvascular pathways leading to dementia.This publication has 38 references indexed in Scilit:
- Perspectives on thyroid hormone action in adult neurogenesisJournal of Neurochemistry, 2015
- Cardiovascular risk factors and future risk of Alzheimer’s diseaseBMC Medicine, 2014
- A Review of the Clinical Consequences of Variation in Thyroid Function Within the Reference RangeJournal of Clinical Endocrinology & Metabolism, 2013
- Alzheimer's diseaseThe Lancet, 2011
- Subclinical hyperthyroidism and dementia: the Sao Paulo Ageing & Health Study (SPAH)BMC Public Health, 2010
- Thyroid Function and the Risk of Alzheimer DiseaseThe Framingham StudyArchives of Internal Medicine, 2008
- Thyroid Disease and the HeartCell Metabolism, 2007
- Low thyroid-stimulating hormone as an independent risk factor for Alzheimer diseaseNeurology, 2004
- Is Alzheimer's disease a neurodegenerative or a vascular disorder? Data, dogma, and dialecticsThe Lancet Neurology, 2004
- Hypothyroidism and AtherosclerosisJournal of Clinical Endocrinology & Metabolism, 2003