Fang, FangKasperzyk, Julie L.Shui, IreneHendrickson, WhitneyHollis, Bruce W.Fall, KatjaMa, JingGaziano, J. MichaelStampfer, MeirMucci, Lorelei A.Giovannucci, EdwardSu, Zheng2019-09-052011Fang, Fang, Julie L. Kasperzyk, Irene Shui, Whitney Hendrickson, Bruce W. Hollis, Katja Fall, Jing Ma, et al. 2011. “Prediagnostic Plasma Vitamin D Metabolites and Mortality among Patients with Prostate Cancer.” Edited by Zheng Su. PLoS ONE 6 (4): e18625. https://doi.org/10.1371/journal.pone.0018625.1932-6203http://nrs.harvard.edu/urn-3:HUL.InstRepos:41292617Background: Laboratory evidence suggests that vitamin D might influence prostate cancer prognosis.Methodology/Principal Findings: We examined the associations between prediagnostic plasma levels of 25(OH) vitamin D [25(OH)D] and 1,25(OH)(2)vitamin D [1,25(OH)(2)D] and mortality among 1822 participants of the Health Professionals Follow-up Study and Physicians' Health Study who were diagnosed with prostate cancer. Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) of total mortality (n = 595) and lethal prostate cancer (death from prostate cancer or development of bone metastases; n = 202). In models adjusted for age at diagnosis, BMI, physical activity, and smoking, we observed a HR of 1.22 (95% CI: 0.97, 1.54) for total mortality, comparing men in the lowest to the highest quartile of 25(OH) D. There was no association between 1,25(OH) 2D and total mortality. Men with the lowest 25(OH) D quartile were more likely to die of their cancer (HR: 1.59; 95% CI: 1.06, 2.39) compared to those in the highest quartile (P(trend) = 0.006). This association was largely explained by the association between low 25(OH) D levels and advanced cancer stage and higher Gleason score, suggesting that these variables may mediate the influence of 25(OH) D on prognosis. The association also tended to be stronger among patients with samples collected within five years of cancer diagnosis. 1,25(OH)(2)D levels were not associated with lethal prostate cancer.Conclusions/Significance: Although potential bias of less advanced disease due to more screening activity among men with high 25(OH) D levels cannot be ruled out, higher prediagnostic plasma 25(OH) D might be associated with improved prostate cancer prognosis.en-USJournal Article2019-09-0510.1371/journal.pone.0018625