to be published in April in the Journal of Clinical Endocrinology & Metabolism is a prospective cohort study of 961 female nursing home residents avg 84yo w/median 25OH vitamin D (25OHD) 17.5nmol/L (7ng/dL) followed for over 2 years. Those in the lowest quartile w/25OHD <14.0nmol/L (5.6ng/dL) had a 49% greater relative risk of all-cause mortality compared to those in the highest quartile with 25OHD >25.5nmol/L (10.2ng/dL), even after taking into account the usual confounders.The latest example
What's amazing to me is that the average 25OHD was so low for all. I suppose we could explain this by considering that most institutionalized patients rarely venture outdoors. Don't forget to look at a meta-analysis of 50 trials involving 94,148 participants avg 74yo published by Cochrane Collaboration last August in which vitamin D3 supplementation over 2 years was responsible for 6% decrease in mortality while D2 made no difference.
Regardless, given the safety and low risk of toxicity as well as the potential benefits from vitamin D supplementation, it seems reasonable to test our nursing home patients and consider supplementing those who are either deficient or insufficient using the same lab (machinery) each time for each patient.