Association of vitamin C, vitamin D, vitamin E and risk of bladder cancer: a dose-response meta-analysis.
Study Goal
The researchers aimed to determine the association between Vitamin C intake and the risk of bladder cancer through a dose-response meta-analysis.
Results Summary
The study found no significant association between Vitamin C and the risk of bladder cancer in the dose-response analysis. The effects of Vitamin C were not statistically significant, unlike Vitamin D and E, which showed varying associations.
Population
General population, with specific analysis among smokers and non-smokers.
Effective Dosage
Not specified
Duration
Not specified
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
vitamin D from diet plus supplement | no change | risk of bladder cancer | - | 0.99 (0.95-1.03) for every 100 IU/day increment | relative risk | #1 |
circulating vitamin D | decrease | risk of bladder cancer | - | 0.95 (0.90-1.00) for every 10 nmol/L increment | relative risk | #2 |
vitamin E from diet plus supplement | no change | risk of bladder cancer | - | 0.96 (0.90-1.02) for every 10 mg/day increment | relative risk | #3 |
vitamin E from diet | decrease | risk of bladder cancer | - | 0.83 (0.72-0.95) for every 10 mg/day increment | relative risk | #4 |
vitamin E from supplement | no change | risk of bladder cancer | - | 0.88 (0.67-1.15) for every 10 mg/day increment | relative risk | #5 |
circulating α-Tocopherol | decrease | risk of bladder cancer | - | 0.84 (0.76-0.94) for every 1 mg/dL increment | relative risk | #6 |
circulating γ-Tocopherol | increase | risk of bladder cancer | - | 1.22 (1.00-1.49) for every 0.1 mg/dL increment | relative risk | #7 |
vitamin D | decrease | risk of bladder cancer | smokers | significant | observed association | #8 |
vitamin D | no change | risk of bladder cancer | non-smokers | not significant | observed association | #9 |
vitamin E | decrease | risk of bladder cancer | smokers | significant | observed association | #10 |
vitamin E | no change | risk of bladder cancer | non-smokers | not significant | observed association | #11 |
vitamin C | no change | risk of bladder cancer | - | no significant association | association | #12 |
vitamin D | decrease | bladder cancer | - | inversely associated | risk | #13 |
vitamin E | decrease | bladder cancer | - | inversely associated | risk | #14 |
α-Tocopherol | decrease | bladder cancer | - | inversely associated | risk | #15 |
γ-Tocopherol | increase | bladder cancer | - | positively associated | risk | #16 |
A dose-response meta-analysis was conducted to assess the association of vitamin C, D, E with risk of bladder cancer. Pertinent studies were identified in PubMed and Embase. The random-effect model was used. The relative risk (95% confidence interval) of bladder cancer was 0.99 (0.95-1.03) for every 100 IU/day increment in vitamin D from diet plus supplement and 0.95 (0.90-1.00) for every 10 nmol/L increment in circulating vitamin D. The effect for every 10 mg/day increment was 0.96 (0.90-1.02) for vitamin E from diet plus supplement, 0.83 (0.72-0.95) from diet and 0.88 (0.67-1.15) from supplement, and the effect was 0.84 (0.76-0.94) for every 1 mg/dL increment in circulating α-Tocopherol and 1.22 (1.00-1.49) for every 0.1 mg/dL increment in circulating γ-Tocopherol. The observed association for vitamin D and vitamin E was significant among smokers but not among non-smokers. No significant association was found between vitamin C and risk of bladder cancer in the dose-response analysis. Based on the dose-response analysis, the risk of bladder cancer might be inversely associated with vitamin D and E (especially α-Tocopherol), but positively associated with γ-Tocopherol.