General and central obesities were associated with increased risk of inflammatory bowel disease: A large‐scale prospective cohort study

Abstract The global incidence of obesity and inflammatory bowel disease (IBD) has been rising during recent decades. We aimed to investigate the prospective association between general and central obesities with IBD in a large‐scale, long‐term follow‐up, population‐based cohort. Participants free of IBD at baseline were enrolled in UK biobank from 2006 to 2010. Multiple baseline general and central obesity indices were assessed (i.e., body mass index [BMI], waist circumference [WC], etc.]. Primary outcome was incident IBD, including ulcerative colitis (UC) and Crohn's disease (CD). Cox proportional hazard model was conducted to investigate the association. Overall, 438,172 participants (aged 56.19 ± 8.10 years; 46.6% male) were included. Based on baseline BMI, 141,464 (32.3%), 187,040 (42.7%), and 107,562 (24.5%) were categorized as normal weight, overweight, and obesity, respectively. During a median of 14.6 years' follow‐up, 2856 incident IBD developed. After multivariable adjustment, individuals with obesity had an 18% higher risk of incident IBD compared to those with normal BMI (hazard ratio [HR] = 1.18, 95% confidence interval [CI]: 1.07–1.30). Similarly, participants in the highest WC quartile had a 28% higher IBD risk compared to the lowest quartile (HR = 1.28, 95% CI: 1.13–1.45). Other central obesity measures showed similar patterns, with 13%–39% higher risk of IBD occurrence in the highest quartile versus the lowest quartile. Similar greater risk of UC and CD was also identified in those with general or central obesity. General and central obesities are both associated with an elevated risk of developing IBD, CD, and UC, emphasizing the critical role of obesity management in preventing IBD.