Cardiovascular Endocrinology

In this issue of Cardiovascular Endocrinology the ongoing controversy concerning the association of low vitamin D levels with the metabolic syndrome is examined by Shanin et al. at the Mansoura School of Medicine, Egypt. Vitamin D has come to be recognized as a multi-faceted hormone that may modify the risk of common cardiovascular and metabolic diseases. The investigators compared a group of obese women satisfying a widely accepted definition of the metabolic syndrome with non-obese first-degree relatives and unrelated healthy women. The women with the metabolic syndrome had significantly lower 25-hydroxy vitamin D levels compared with the non-obese control groups. Among the first-degree relatives who would be expected to share genetic and environmental dispositions to metabolic syndrome low vitamin D status was associated with an unfavourable cardiometabolic profile. While a cross-sectional study does not provide a sound basis for determining cause-andeffect relationships some general findings in this report are of interest from a public health perspective. In particular, according to their definition the authors found a high prevalence of vitamin D deficiency among the women in their study, an observation that is in line with other studies from the Middle East and Gulf states. While obesity may reduce the bioavailability of vitamin D the authors hypothesize that the impact of skin pigmentation and veiling should also be considered. Given the high prevalence rates of obesity, the metabolic syndrome and type 2 diabetes in this region of the world the pathophysiological implications of vitamin D deficiency merit further evaluation in prospective, and perhaps interventional, studies in these populations. The authors point out that Egypt offers a unique mix of different races and ethnicities that might be of value in this regard.