Thyroid Hormones: Positive Relationships With Cognition in Healthy, Euthyroid Older Men

来自 EBSCO

阅读量：

作者：

PN Prinz，JM Scanlan，PP Vitaliano，KE Moe，B Soo，T Bert，GR Merriam，LH Larsen，RH Lester

展开

摘要：

Background. Although the association of clinical hypothyroidism with cognitive deficits is well known, the cognitive effects of thyroid hormones in euthyroid subjects are less studied and understood. The purpose of this study was to examine thyroid-cognition relationships in healthy, euthyroid older men. Methods. We examined healthy men (N = 44, mean age = 72), excluding clinically hypothyroid/hyperthyroid or diathetic/hyperglycemic subjects and those with dementia, depression, CNS medications, or recent illness. Plasma samples obtained across a 24-hour period were pooled, then assayed for total thyroxine (TT4), total triiodothyronine (TT3), and T3 resin uptake. Free thyroxine index (FT4I) was calculated. A broad cognitive battery (including the Wechsler Adult Intelligence Scale—Revised [WAIS-R], the Dementia Rating Scale [DRS], and the Rivermead Behavioral Profile [PROFILE]) was administered to all subjects. Results. Regression analyses controlling age and education showed TT4 and FT4I to have significant positive relationships with measures of overall cognition; TT4 accounted for 8% to 12% of the variance in omnibus cognitive measures such as WAIS Performance, WAIS Verbal score, and GLOBAL cognitive scores. Conclusions. Our findings suggest that within "normal" range of variation in plasma thyroid hormones, TT4 but not T3 positively associates with general cognition in healthy elderly men.

展开

关键词：

Humans Dementia Thyroxine Thyroid Hormones Cognition Memory Regression Analysis Intelligence Reaction Time Cognition Disorders