Comparing the clinical outcomes of young-onset and adult-onset ulcerative colitis: a multi-center Korean Association for the Study for Intestinal Diseases study

A systematic review and meta-analysis of prospective studies on obesity and risk of inflammatory bowel disease

CONTEXT

There are only a few systematic reviews on the association of obesity with risk of inflammatory bowel disease (IBD) to date.

OBJECTIVE

The current study was undertaken to systematically review prospective cohort studies on the association between body mass index (BMI) and risk of IBD. It was carried out according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines.

DATA SOURCES

Relevant prospective cohort studies published from 1969 to July 2020 were searched through PubMed, MEDLINE, SCOPUS, EMBASE, and Google Scholar, using suitable keywords.

DATA EXTRACTION

Hazard ratios (HRs) or relative risks (RRs) and 95% confidence intervals (CIs) for IBD or its subtypes across categories of BMI were extracted.

DATA ANALYSIS

The log HRs/RRs, including standard errors, were calculated based on reported HRs or RRs and their 95% CIs, and overall effect size was calculated using a fixed-effects model. All statistical analyses were done using STATA version 14.0 (Stata Corp LP, College Station, TX, USA).

CONCLUSION

Overall, 9 studies were included. Combining findings from 5 studies, a statistically significant 21% lower risk of ulcerative colitis incidence was found in patients with obesity than in those with normal weight (RR, 0.79; 95% CI, 0.68-0.92; I2= 0.0%), but not with risk of ulcerative colitis exacerbation, as found by meta-analysis of 3 studies. Pooling data from 5 studies, no significant differences were seen in the risk of Crohn's disease incidence between patients in the highest range of BMI and those in the normal range. In addition, no significant nonlinear association was found between BMI and risk of Crohn's disease (P=0.94). A significant inverse association was found between obesity and total IBD incidence (RR, 0.76; 95% CI, 0.66-0.88; I2=93.2%), but not between increasing BMI and IBD exacerbation, or between increasing BMI and IBD incidence.

Changing treatment paradigms for the management of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic and progressive inf lammatory condition of the gastrointestinal tract causing bowel damage, hospitalizations, surgeries, and disability. Although there has been much progress in the management of IBD with established and evolving therapies, most current approaches have failed to change the natural course. Therefore, the treatment approach and follow-up of patients with IBD have undergone a significant change. Usage of immunosuppressants and/or biologics early during the course of the disease, known as top-down or accelerated step-up approach, was shown to be superior to conventional management in patients who had been recently diagnosed with IBD. This approach can be applied to selected groups based on prognostic factors to control disease activity and prevent progressive disease. Therapeutic targets have been shifted from clinical remission mainly based on symptoms to objective parameters such as endoscopic healing due to the discrepancies observed between symptoms, objectively evaluated inf lammatory activity, and intestinal damage. The concept of treat-to-target in IBD has been supported by population-based cohort studies, post hoc analysis of clinical trials, and meta-analysis, but more evidence is needed to support this concept to be applied to the clinical practice. In addition, individualized approach with tight monitoring of non-invasive biomarker such as C-reactive protein and fecal calprotectin and drug concentration has shown to improve clinical and endoscopic outcomes. An appropriate de-escalation strategy is considered based on patient demographics, disease features, current disease status, and patients' preferences.