Subclinical Hypothyroidism and Cognitive Impairment: Systematic Review and Meta-Analysis.

The association between subclinical hypothyroidism (sHT) and cognitive impairment or risk of dementia is not well-defined, especially in the elderly, where the assessment of central nervous system function is challenging. The aim of this systematic review and meta-analysis was to evaluate the possible effect of sHT on cognitive decline and the risk of dementia.