Serum levels of vitamin E forms and risk of cognitive impairment in a Finnish cohort of older adults

• Published in: Experimental gerontology Vol. 48; no. 12; pp. 1428 - 1435
• Main Authors: Mangialasche, Francesca, Solomon, Alina, Kåreholt, Ingemar, Hooshmand, Babak, Cecchetti, Roberta, Fratiglioni, Laura, Soininen, Hilkka, Laatikainen, Tiina, Mecocci, Patrizia, Kivipelto, Miia
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 01.12.2013
• Subjects: Age Factors; Aged; Aging - blood; Aging - psychology; Alzheimer Disease - blood; Alzheimer Disease - diagnosis; Alzheimer Disease - epidemiology; Alzheimer Disease - psychology; Alzheimer's disease; Alzheimers disease; Biomarkers - blood; Chi-Square Distribution; Cholesterol - blood; Cognition; Cognitive Dysfunction - blood; Cognitive Dysfunction - diagnosis; Cognitive Dysfunction - epidemiology; Cognitive Dysfunction - psychology; Cognitive impainment; Cognitive impairment; Disease Progression; Female; Finland - epidemiology; Humans; Incidence; Linear Models; Logistic Models; Male; Odds Ratio; Oxidative Stress; Oxidative/nitrosative stress; Prospective Studies; Risk Factors; Time Factors; Tocopherol; Tocopherols - blood; Tocotrienol; Tocotrienols - blood; Vitamin E; Vitamin E - blood; DSM-IV; CERAD; Tocotrienol; MRI; NS; CNS; CDR; HDL; SD; LDL; Vitamin E; MMSE; RNS; 5-NO2-γ-tocopherol; APOE; Alzheimer's disease; HPLC; BMI; Cognitive impairment; CAIDE; AD; OR; αTQ; OS; CI; NINCDS-ADRDA; MCI; CV; Oxidative/nitrosative stress; Tocopherol; Central nervous system; Coefficient of variation; Body mass index; 5-NO-γ-tocopherol; α-Tocopherylquinone; National Institute of Neurologic and Communicative Disorders and Stroke–Alzheimer's Disease and Related Disorders Association; Nitrosative stress; High Performance Liquid Chromatography; Low-density lipoprotein; High-density lipoprotein; Clinical Dementia Rating Scale; Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition; Mini-Mental State Examination; Oxidative stress; Reactive nitrogen species; Apolipoprotein E; Standard deviation; Consortium to Establish a Registry for Alzheimer's Disease; Cardiovascular Risk Factors, Aging, and Dementia study; Confidence interval; Magnetic resonance imaging; Odds ratio; mild cognitive impairment; 5-nitro-γ-tocopherol
• ISSN: 0531-5565; 1873-6815; 1873-6815
• DOI: 10.1016/j.exger.2013.09.006

Vitamin E includes eight natural antioxidant compounds (four tocopherols and four tocotrienols), but α-tocopherol has been the main focus of investigation in studies of cognitive impairment and Alzheimer's disease. To investigate the association between serum levels of tocopherols and tocotrienols, markers of vitamin E oxidative/nitrosative damage (α-tocopherylquinone, 5-nitro-γ-tocopherol) and incidence of cognitive impairment in a population-based study. A sample of 140 non-cognitively impaired elderly subjects derived from the Cardiovascular Risk Factors, Aging, and Dementia (CAIDE) study was followed-up for 8years to detect cognitive impairment, defined as development of mild cognitive impairment (MCI) or Alzheimer's dementia. The association between baseline serum vitamin E and cognitive impairment was analyzed with multiple logistic regression after adjusting for several confounders. The risk of cognitive impairment was lower in subjects in the middle tertile of the γ-tocopherol/cholesterol ratio than in those in the lowest tertile: the multiadjusted odds ratio (OR) with 95% confidence interval (CI) was 0.27 (0.10–0.78). Higher incidence of cognitive impairment was found in the middle [OR (95% CI): 3.41 (1.29–9.06)] and highest [OR (95% CI): 2.89 (1.05–7.97)] tertiles of the 5-NO2-γ-tocopherol/γ-tocopherol ratio. Analyses of absolute serum levels of vitamin E showed lower risk of cognitive impairment in subjects with higher levels of γ-tocopherol, β-tocotrienol, and total tocotrienols. Elevated levels of tocopherol and tocotrienol forms are associated with reduced risk of cognitive impairment in older adults. The association is modulated by concurrent cholesterol concentration. Various vitamin E forms might play a role in cognitive impairment, and their evaluation can provide a more accurate measure of vitamin E status in humans. •Serum levels of various vitamin E forms are associated with reduced incidence of cognitive impairment in older adults.•Cholesterol modulates the association between vitamin E and cognitive impairment.•Assessment of all vitamin E forms might better reflect vitamin E status in humans.