Affiliations: [a]
Medical Department, Section of Geriatrics, Lovisenberg Diaconal Hospital, Nydalen, Oslo, Norway
| [b] Institute of Clinical Medicine, Campus Ahus, University of Oslo, Blindern, Norway
| [c] Health Services Research Unit, Akershus University Hospital, Lørenskog, Norway
| [d] Department of Geriatric medicine, Oslo University Hospital, Nydalen, Oslo, Norway
| [e]
Norwegian National Advisory Unit on Ageing and Health, Vestfold Hospital Trust, Tønsberg, Norway
| [f] Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| [g] Karolinska Institutet, Department for Neurobiology, Caring Science and Society, Division of Clinical Geriatrics Novum Research Park, Stockholm, Sweden
Correspondence:
[*]
Correspondence to: Jelena Zugic Soares, Medical Department, Section of Geriatrics, Lovisenberg Diaconal Hospital. PB 4970 Nydalen, 0440 Oslo, Norway. Tel.: +4797146111; E-mail: jelenazugic@hotmail.com.
Abstract: Background:Allele ɛ4 of the apolipoprotein (APOE ∈4) gene is the strongest known genetic risk factor for late-onset sporadic Alzheimer’s disease. A possible relationship between vitamin D and APOE is not yet clear. Objective:In this exploratory, cross-sectional study, we examined the association between serum levels of 25-hydroxyvitamin D [25(OH)D] and brain volumes and the associations of both serum levels of 25(OH)D and APOE polymorphism to brain volumes in 127 persons (mean age 66 years) with cognitive symptoms. Methods:All subjects were examined with fully automated software for MRI volumetry, NeuroQuant. Results:After adjustment for relevant covariates, higher serum 25(OH)D levels were associated with greater volumes of cortical gray matter on both left (p = 0.02) and right (p = 0.04) sides. When both 25(OH)D levels and APOE genotype were used as the main covariates, no significant associations were found between vitamin D level and brain volume in any of the 11 brain regions. In adjusted models, only homozygous but not heterozygous APOE ∈4 allele carriers had significantly larger inferior lateral ventricles (p = 0.003) and smaller hippocampal volume (p = 0.035) than those without ɛ4. Homozygous APOE ∈4 carriers also had significantly higher vitamin D levels (p = 0.009) compared to persons without the APOE ∈4 allele. Conclusion:Higher vitamin D levels might have a preserving effect on cortical grey matter volume.
