Previous research has suggested that vitamin D and sunlight are related to cardiovascular outcomes, but associations between sunlight and cardiovascular disease (CVD) risk factors have not been extensively investigated. Therefore, Dr. Shia T. Kent, postdoctoral trainee in the department of epidemiology, and Dr. Leslie A. McClure, professor in the department of biostatistics, at the University of Alabama at Birmingham—collaborating with Dr. George Howard, professor, and Dr. Suzanne E. Judd, associate professor, also in UAB’s department of biostatistics—examined whether increased sunlight exposure was related to improved cardiovascular risk factor status.

[Photo: Dr. Shia T. Kent and Dr. Leslie A. McClure]

The team merged residential histories with satellite, ground monitor, and model reanalysis data to determine previous-year sunlight radiation exposure for 17,773 Black and White REasons for Geographic and Racial Differences in Stroke (REGARDS) participants ages 45 and older from the United States. Exploratory and confirmatory analyses were performed by randomly dividing the sample into halves. Logistic regression models were used to examine relationships with cardiovascular risk factors.

Higher compared with lower levels of sunlight exposure were associated with lower high-density lipoprotein cholesterol levels in both exploratory and confirmatory models. Further, lower compared with higher levels of sunlight exposure were associated with higher systolic blood pressure in exploratory but confirmatory models, suggesting further research is necessary about the relationship between sunlight exposure and blood pressure. Although the observed associations were weak, the results of this study suggest that higher long-term sunlight exposure has an association with lower high-density lipoprotein levels. Thus, future work is required to determine more definitively whether sunlight exposure may affect cardiovascular outcomes through these risk factors.

“Sunlight Exposure and Cardiovascular Risk Factors in the REGARDS Study: A Cross-Sectional Split-Sample Analysis” was published recently in the journal BMC Neurology.

Journal article: http://www.biomedcentral.com/1471-2377/14/133/abstract