Circulating 25-Hydroxyvitamin D and Prostate Cancer Survival

Area of Science:

• Nutritional epidemiology
• Prostate cancer research
• Vitamin D metabolism

Background:

• Conflicting evidence exists on vitamin D's role in prostate cancer development.
• Previous studies often did not focus on prostate cancer mortality.
• Higher vitamin D levels may not prevent, but potentially increase, prostate cancer risk.

Purpose of the Study:

• To investigate the association between prediagnostic serum vitamin D levels and prostate cancer survival.
• To examine the impact of vitamin D on prostate cancer-specific mortality.

Main Methods:

• Analysis of serum 25-hydroxy-vitamin D (25(OH)D) in 1,000 prostate cancer cases from the ATBC Study.
• 23-year follow-up to identify 363 prostate cancer deaths.
• Cox proportional hazards models used to assess mortality risk by vitamin D levels, adjusted for covariates.

Main Results:

• Higher prediagnostic serum 25(OH)D levels were associated with a reduced risk of prostate cancer death (Q5 vs. Q1 HR: 0.72).
• This association was independent of cancer stage or grade at diagnosis.
• The protective effect was more pronounced in men with longer survival times (≥3.3 years).

Conclusions:

• Higher serum 25(OH)D levels, measured years before diagnosis, are linked to improved prostate cancer survival.
• These findings highlight a potential role for vitamin D in mitigating prostate cancer mortality.
• Results have significant public health implications given the inconsistent evidence on vitamin D and prostate cancer.