Relationship of thyroid function and brain volume changes in Alzheimer's disease / 中华老年心脑血管病杂志

ABSTRACT

Objective To investigate the relationship between thyroid function and brain volume in patients with Alzheimer's disease(AD).Methods A total of 64 AD patients(AD group)and 36 patients with mild cognitive impairment(MCI group)admitted in our department from January 2020 to March 2022 were enrolled in this study.Another 19 healthy individuals who had no cogni-tive impairment or psychiatric disorders were enrolled and served as normal control group.Their levels of free triiodothyronine(FT3),free thyroxine(FT4)and thyroid stimulating hormone(TSH)were detected by electrochemical luminescence assay.Results FT3 level was significantly decreased in the MCI group and AD group than the normal control group[2.50(2.28,2.60)ng/L and 2.07(1.97,2.30)ng/L vs 2.76(2.55,2.93)ng/L,P＜0.05],and the decrease in the AD group was more obvious than that in the MCI group.The volumes of the midbrain,pons,medulla oblon-gata,hippocampus,amygdala and temporal lobe were significantly smaller in the AD group than the MCI group(P＜0.05,P＜0.01).Spearman correlation analysis and multivariate linear regres-sion analysis showed that in the AD patients,FT3 and FT4 levels were positively while TSH level was negatively correlated with the volumes of both right and left hippocampus and amygdala(P＜0.05,P＜0.01),and TSH level was also negatively correlated with the left temporal lobe volume(P＜0.05).Conclusion Thyroid dysfunction is associated with reduced brain volume in AD patietns,and may contribute to the progression of AD cognitive dysfunction and brain atrophy.