Friday, January 08, 2010


Black Americans have always had a higher CVS mortality than white Americans. This association has been known for a longtime and it was often put down to poor socio-economic status and obesity, hypertension and diabetes. All this seem to be true.
In the latest issue of the Annals of Family Medicine, Jan 2010, Dr K Fiscella and colleagues studied firstly, the association of Black Americans and CVS mortality and also the serum vitamin D levels and CVS mortality, USA. They actually did a retrospective cohort Study going back into records of the National Health and Nutrition examination Survey ( NHANES III ) from 1988-1994, an also the records of the " cause specific mortality or National Death Index 2001. They were hoping to answer 1. that Blacks had higher CVS mortality, and 2. that this increase mortality could be due to a lower Vit D level, due to the fact that darker skin manufactured less Vit D from the sun. Well, the authors were able to prove the first. That Black Americans had a higher CVS mortality than whites. But when they added the confounding factor of serum Vit D, that correlation was lost. Suggesting that the higher CVS mortality in blacks was not related to serum Vit D levels. That it may be due to poverty or other diseases associated with the lower socio-economic status.
I took out this piece because I was trying to correlate the higher CVS mortality in Indians in South East Asia, and whether or not Vit D was a factor, as this can be easily corrected with Vit D supplements. Alas, this is not to be so. It looks like dark skin maybe a minor risk factor for heart disease and mortality, and Vit D may not be the reason. The usual risk factors of cigarette smoking, obesity, hypertension, diabetes, and dyslipidemia, maybe the main factors. Certainly the stress of life on the darker skin individual, and the diet that they can afford, the lack of exercise, cigarettes or cigars, may also be important in this group.
Be that as it may, it is true that darker skin individuals have a higher CVS mortality when compared to fairer skin and that it is not due to low Vit D levels, although there is much evidence that low Vit D levels may be associated with heart disease. Looks like not in this case here.

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