Key Findings:
Using data from a Serbian case–control study involving 322 cases and 239 controls, a strong and consistent inverse association of bladder cancer was noted with dietary ALA. Consistent with a few previous studies, no association between bladder cancer risk and intake of EPA and DHA was detected. LA intake showed borderline reduced risk association. The authors concluded that the effects of individual fatty acids need to be examined separately.
ABSTRACT:
The role of dietary fat in bladder cancer aetiology is currently unclear due to few studies, equivocal findings and a lack of information on important dietary fatty acids. The aim of the present study was to investigate the association between the intake of major dietary fats and fatty acids and the risk of bladder cancer. A case–control study was conducted in New Hampshire, USA. Dietary data were collected from 322 cases and 239 controls, and OR and 95% CI were calculated using unconditional logistic regression. Adjustment was made for potential confounders: sex, age, smoking status, pack-years smoked, cholesterol and energy intake. Statistically significant reduced odds of bladder cancer were observed for high intakes (highest quartile v. lowest quartile) of alpha-linolenic acid (ALA) (OR 0.26, 95% CI 0.10, 0.65; P for trend<0.01) and vegetable fat (OR 0.39, 95% CI 0.18, 0.86; P for trend<0.03). Borderline statistically significant reduced odds were detected for polyunsaturated fat (OR 0.43, 95% CI 0.19, 0.98; P for trend<0.07) and linoleic acid (OR 0.43, 95% CI 0.19, 0.96; P for trend <0.06). These fats and fatty acids were highly correlated and following adjustment for each other, the only potential inverse association to remain was for ALA. The present findings suggest that ALA may have a protective role against developing bladder cancer; however, further investigation and replication in other epidemiological studies are required. Future research should focus on the type, source and quantities of different dietary fatty acids consumed. (Author’s Abstract)