19 Nov Genetically Low Vitamin D Levels Linked To Increased Mortality
MedicalResearch.com Interview with:
Børge G Nordestgaard, MD, DMSc
Professor, University of Copenhagen
Chief Physician, Herlev Hospital, Copenhagen University Hospital
Dept. Clinical Biochemistry Herlev Ringvej Herlev, Denmark
Medical Research: What is the background for this study? What are the main findings?
Prof. Nordestgaard: Many people take vitamin D supplements with the hope of reducing morbidity and mortality. However, it is unclear whether low vitamin D per se is a direct cause of increased mortality or whether it is simply a marker of poor lifestyle in general and/or underlying hidden disease. Our study involved 95,766 white participants of Danish descent from three cohorts in Copenhagen, who had genetic variants known to affect vitamin D levels. We found that genetically low vitamin D levels were associated with increased all-cause mortality, cancer mortality, and other mortality, but not with cardiovascular mortality. This is important as such genetics studies cannot be explained by poor lifestyle or hidden disease, as neither can change your genes.
Medical Research: What should clinicians and patients take away from your report?
Prof. Nordestgaard: The clinical implication of our findings remain limited, as widespread vitamin D supplementation can be recommended only after benefit is shown in randomised intervention trials. Such a study is likely to report in 2017, the VITAL study. Until then increasing vitamin D via modest sun exposure of your skin and by eating food rich in vitamin D, like fatty fish, are advisable.
Medical Research: What recommendations do you have for future research as a result of this study?
Prof. Nordestgaard: Wait for the VITAL study to report in 2017. Also, I hope to see other reports of the importance of genetically low vitamin D on risk of morbidity and mortality, to confirm the results of our study.
Genetically low vitamin D concentrations and increased mortality: mendelian randomisation analysis in three large cohorts
BMJ 2014; 349 doi: http://dx.doi.org/10.1136/bmj.g6330 (Published 18 November 2014) Cite this as: BMJ 2014;349:g6330