Smoking and alcohol consumption as risk factors for colonic diverticulosis and its complications: Systematic review and meta-analysis

Background: Colonic diverticulosis (CD) is a prevalent condition marked by small pouches (diverticula) in the colon wall, particularly in those over 50. Many studies have investigated various risk factors, but the relationship between smoking, alcohol consumption, and CD remains to be decided. This meta-analysis analyses the association between these lifestyle factors and the risk of CD and its complications. Methods: A comprehensive literature search was conducted using PubMed, Embase, and Google Scholar to find relevant studies. Inclusion criteria were based on predefined eligibility standards, focusing on observational studies reporting smoking, alcohol consumption, and CD. Using random effect models, Mantel–Haenszel odds ratios and associated 95% confidence intervals were produced to report the overall effect size. Statistical significance was set at P < .05. Egger’s regression test and Begg–Mazumdar’s rank test were used to assess publication bias. The quality of the included studies was assessed using the Newcastle–Ottawa Scale. Results: Sixty-two studies encompassing 5,66,903 patients were included finally, where the mean age was 73.8 years, and 44.53% were female. Smoking increased the risk of CD (odds ratio [OR]: 1.36, 95% confidence interval [CI]: 1.24–1.48), diverticulitis (OR: 1.59, 95% CI: 1.01–2.51), and diverticular bleeding (OR: 1.51, 95% CI: 1.13–2.02). Ex-smokers also showed a higher risk of CD compared to nonsmokers (OR: 1.31, 95% CI: 1.08–1.59). Alcohol consumption was associated with an increased risk of CD (OR: 1.41, 95% CI: 1.09–1.82). However, no association was found between alcohol consumption and diverticular bleeding (OR: 1.15, 95% CI: 0.77–1.71) or diverticulitis (OR: 1.36, 95% CI: 0.98–1.88). No publication bias was clear in the analysis. Conclusion: This meta-analysis suggests an association between smoking, alcohol consumption, and increased risk of CD. Smoking is associated with an increased risk of CD and diverticular bleeding. The relationship between alcohol consumption and diverticular disease requires further investigation. Future research should explore the mechanisms by which these factors influence the development of CD to understand and inform public health recommendations.