ASPO Abstracts
Selenium supplementation for chemoprevention and odds of development of diabetes: A systematic review
Category: Lifestyles Behavior, Energy Balance & Chemoprevention, Lifestyles Behavior, Energy Balance & Chemoprevention
Conference Year: 2018
Abstract Body:
The trace element selenium (Se) gained momentum as a potential chemopreventive agent with the publication of the results of the Nutritional Prevention of Cancer (NPC) trial in 1996, wherein secondary analyses revealed statistically significant reductions in colorectal and prostate cancer incidence for those in the Se supplementation arm compared to placebo. More recently, there has been evidence of an increased risk for diabetes among individuals who received Se as compared to those randomized to placebo in the NPC and other chemoprevention trials. We therefore conducted a systematic review of the literature to determine whether selenium is related to risk of diabetes. We employed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and identified a total of seven observational studies and three clinical trials that were eligible for inclusion. Of the observational studies, one case-control and four cross-sectional studies reported significantly increased odds for diabetes among those with the highest category of serum selenium levels compared to the lowest; while the results of two case-control studies showed no significant differences between those with and without diabetes for whole blood selenium levels. With regard to clinical trials, a total of three completed chemoprevention trials comprising over 20,000 participants were identified for inclusion: the NPC Trial, the Selenium and Vitamin E Cancer Prevention Trial (SELECT) and the Selenium Trial (SEL). In the NPC Trial, the reported hazard ratio (95% confidence interval) for the development of diabetes among those supplemented with Se vs. placebo was 1.55 (1.03-2.33). For SELECT, the HR (95% CI) was 1.07 (0.94-1.22); while for SEL, it was 1.25 (0.74-2.11). After combining the data from these trials, the OR (95% CI) for diabetes among those supplemented with Se vs. placebo was 1.11 (1.00-1.23). These results suggest that there may be a modest increase in the odds of diabetes with higher circulating Se concentrations or with Se supplementation for chemoprevention. However, further work is required to ascertain if there is heterogeneity of treatment effect among study participants by variables such as age, genetic background, baseline selenium status, or sex.
Keywords: Selenium Chemoprevention Diabetes