No abstract

Context: Low serum calcidiol has been associated with multiple comorbidities and mortality but no "safe" range has been found for the upper concentration.Objective: We aim to establish the upper threshold of serum calcidiol, beyond which there is an increased risk for acute coronary syndrome and/or mortality.Design, Setting, and Participants: We extracted data for 1 282 822 Clalit Health Services members aged Ͼ45 between July 2007 and December 2011. Records of mortality or acute coronary syndrome were extracted during the follow-up period. Kaplan-Meier analysis calculated time to episode and Cox regression models generated adjusted hazard ratios for episode by calcidiol group (Ͻ10, 10.1-20, 20.1-36, and Ͼ36.1 ng/mL).Outcome Measures: Acute coronary syndrome subsuming all-cause mortality.Results: During the 54-month study period, 422 822 Clalit Health Services members were tested for calcidiol, of which 12 280 died of any cause (905 with acute coronary syndrome) and 3933 were diagnosed with acute coronary syndrome. Compared to those with 20 -36 ng/mL, the adjusted hazard ratios among those with levels of Ͻ10, 10 -20, and Ͼ36 ng/mL were 1.88 (confidence interval [CI]: 1.80 -1.96), 1.25 (CI: 1.21-1.30), and 1.13 (CI: 1.04 -1.22) (P Ͻ .05), respectively. Limitations:The study cohort comprised only 30% of the population, those tested for vitamin D. The small sample size of those with calcidiol Ͼ36 ng/mL prevented further analysis of this group. Conclusions:Vitamin D in the 20 -36 ng/mL range was associated with the lowest risk for mortality and morbidity. The hazard ratio below and above this range increases significantly. (J Clin Endocrinol Metab 98: 2160 -2167, 2013) T here is increasing evidence over the last several years of the pivotal role of vitamin D in human physiology. Evidence from multiple studies showed that low levels of serum calcidiol raise the risk of various morbidities (1)(2)(3)(4)(5) and confirmed the vital influence of vitamin D on human health with its direct involvement in more than 3000 genes (6) and indirect involvement in many others (7). There is also compelling evidence regarding the influence of low

No abstract