Thyroid: Relationship between thyroid hormone levels and Alzheimer's pathology in people with normal thyroid function

Although several studies have reported a link between thyroid dysfunction and Alzheimer's disease (AD), it is not clear how mild thyroid dysfunction within the normal TSH range affects ADA study published recently in Thyroid, an authoritative journal of thyroid disease, was conducted to assess the association between thyroid hormones and AD pathology in people with normal thyroid functionthe prospective cross-sectional study included 69 subjects with TSH levels between 0.5 and 4.5 siU/L who received 18 F-fluorooctaridesThe researchers used radioimmune assays to determine the subjects' serum free thyroxine (fT4) and thyroid stimulator (TSH) levelsThe researchers used neuropsychological tests to assess the cognitive function of the subjects and compared differences in the burden of cerebral amyloid beta (A-beta) in the high normal range of TSH (TSH s.5?IU/mL) and TSH (TSH 2.5 siU/mL) in the low normal range groupThe researchers analyzed multiple linear regression scored on age, gender, educational level, and neuropsychiatry scale to assess the relationship between thyroid hormone levels and a beta load and cognitive function in the brainThe cerebral A-beta burden in the TSH high normal range group was significantly higher than that of the TSH low normal range group (1.53 x 0.31 vs1.35 to 0.22, p.009)The fT4 level was negatively correlated with the brain A beta burden (beta -0.240, p-0.035), while the TSH level was positively correlated with the a-beta burden of the brain (beta-0.267, p-0.020)From the neuropsychological test scores, fT4 levels were also positively correlated with cognitive functionshows that thyroid hormone levels in people with normal thyroid function are related to AD pathologyThe results of the study suggest that AD may occur even in people with normally high TSH levels