Serum vitamin D in patients with mild cognitive impairment and Alzheimer's disease

• Published in: Brain and behavior 2018-03, Vol.8 (3), p.e00936-n/a
• Main Authors: Ouma, Shinji, Suenaga, Midori, Bölükbaşı Hatip, Funda F., Hatip‐Al‐Khatib, Izzettin, Tsuboi, Yoshio, Matsunaga, Yoichi
• Format: Article
• Language: English
• Subjects: 1,25(OH)2D3; 25(OH)D3; Age Factors; Aged; Aged, 80 and over; Alzheimer Disease - blood; Alzheimer Disease - classification; Alzheimer Disease - diagnosis; Alzheimer's disease; Biomarkers - blood; Calcitriol - blood; Cognitive ability; Cognitive Dysfunction - blood; Cognitive Dysfunction - classification; Cognitive Dysfunction - diagnosis; Correlation of Data; Female; Humans; Male; Mental Status Schedule; mild cognitive impairment; mini‐mental state examination; Original Research; ROC Curve; Sensitivity and Specificity; Sex Factors; Vitamin D; Vitamin D - analogs & derivatives; Vitamin D - blood
• ISSN: 2162-3279; 2162-3279
• DOI: 10.1002/brb3.936

Objectives To determine the relevance of Mini‐Mental State Examination (MMSE), serum 25‐hydroxyvitamin D (25(OH)D3), and 1,25(OH)2D3 concentrations to mild cognitive impairment (MCI) and various stages of Alzheimer's disease (AD). Materials and Methods The study included 230 participants (>74 years) allocated to three main groups: 1‐healthy subjects (HS, n = 61), 2‐patients with MCI (n = 61), and 3‐ patients with Alzheimer's disease (AD) subdivided into three stages: mild (n = 41), moderate (n = 35), and severe AD (n = 32). The cognitive status was evaluated using MMSE. Serum 25 (OH)D3 (ng/ml) and 1,25(OH)2D3 concentrations (pg/ml) were determined by competitive radioimmunoassay. Results MMSE scores and 25(OH)D3 were decreased in MCI and all stages of the AD in both genders. MMSE variability was due to gender in HS (11%) and to 25(OH)D3 in MCI (15%) and AD (26%). ROC analysis revealed an outstanding property of MMSE in diagnosis of MCI (AUC, 0.906; CI 95%, 0.847–0.965; sensitivity 82%; specificity, 98%) and AD (AUC, 0.997; CI 95%, 0.992–1; sensitivity, 100%; specificity, 98%). 25(OH)D3 exhibited good property in MCI (AUC, 0.765; CI 95%, 0.681–0.849; sensitivity, 90%; specificity, 54%) and an excellent property in diagnosis of AD (AUC, 0.843; CI 95%, 0.782–0.904; sensitivity, 97%; specificity, 79%). Logistic analyses revealed that, in MCI, MMSE could predict (or classify correctly) with 97.6% accuracy (Wald, 15.22, β, −0.162; SE, 0.554; OR = 0.115:0.039–0.341; p = .0001), whereas 25(OH)D3 with 80% accuracy (Wald, 41,013; β, −0.213; SE, 0.033; OR = 0.808: 0.757–863; p = .0001). 25(OH)D3 was the only significant predictor for the severe AD and contributed to MMSE variability. Age and gender were significant predictors only in the moderate AD. In patients with MCI, 25(OH)D3 and 1,25(OH)2D3 were correlated men, but in case of the AD, they were correlated in women. Conclusions MMSE and serum 25(OH)D3 concentrations could be useful biomarkers for prediction and diagnosis of MCI and various stages of the AD. The results support the utility of vitamin D supplementation in AD therapy regimen. Vitamin D seems not only as a valuable supplementation in Alzheimer's disease therapy regimen but also as a biomarker in the differential diagnosis of mild cognitive impairments and mild, moderate, and severe Alzheimer's disease.