Dietary Anthocyanin Intake, Genetic Risk, and Incident Ulcerative Colitis: A Prospective Cohort Study

Abstract

evidence from animal experiments indicates that anthocyanin supplements can contribute to intestinal health. Nevertheless, no evidence has linked dietary anthocyanins to the prevention potential against inflammatory bowel disease (IBD) in humans. We leveraged data from 188,044 IBD-free individuals (mean age 59 years; 55.2% females) from the prospective cohort UK Biobank. The anthocyanin intake was estimated using dietary information from validated 24 h dietary recalls. Incident IBD was ascertained via national health-related records. Genetic susceptibility to Crohn's disease (CD) and ulcerative colitis (UC) was estimated by polygenic risk scores and further categorized into low- and high-risk groups by median value. The Cox proportional regression model was applied to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs). During the mean follow-up of 9.7 years, we documented 255 CD and 606 UC. We found that compared with participants with the lowest quartiles of anthocyanin intake, those in the highest quartiles were associated with 24% (95% CI 6%-38%, p = 0.012; p-trend = 0.003) and 35% (95% CI 16%-49%, p = 0.001; p-trend < 0.001) reduced risk of IBD and UC, respectively. The inverse associations were stronger (p-interaction = 0.022) among individuals with a high genetic risk of UC. We did not observe a significant association between anthocyanin intake and CD (p-trend = 0.536). Higher dietary anthocyanin intake was associated with reduced risk of IBD and UC, but not CD. Genetic factors may modify the influence of dietary anthocyanin on UC susceptibility, and possible mechanisms need to be further elucidated in the future.

Keywords: cohort study; flavonoid; genetic risk.

FIGURE 1

Flowchart of the study.

FIGURE 2

Associations of dietary anthocyanin with risk of IBD, CD, and UC using restricted cubic curves. The results were based on the fully adjusted model. The vertical axis represents the risk of interested outcomes. The solid line in orange represents hazard ratios, and the dashed lines in orange represent 95% confidence intervals. Density plots of anthocyanin were presented in blue. CI, confidence interval; HR, hazard ratio.

FIGURE 3

Simple summary diagram of the possible mechanisms of anthocyanins for UC prevention.