Breakfast skipping and steroid withdrawal in ulcerative colitis: A population-based study in Japan

Ulcerative colitis (UC) is a chronic inflammatory bowel disease with increasing prevalence in Japan. While pharmacological therapies have advanced, the effect of dietary timing, particularly breakfast skipping, on disease course remains unclear. We conducted a retrospective cohort study using the JMDC database (2015-2023), which contains claims and annual health checkup data from about 8.17 million insured individuals. We identified 1645 UC patients who initiated corticosteroid therapy within 1 year after diagnosis and were followed for at least 3 years. Breakfast skipping was defined as skipping breakfast more than three times per week. The primary outcome was steroid withdrawal, defined as discontinuation of corticosteroid prescriptions. Logistic regression models estimated odds ratios (ORs) and 95% confidence intervals (CIs) for steroid withdrawal according to breakfast habits. Among 1645 patients, 303 (18.4%) reported skipping breakfast. Steroid withdrawal occurred in 543 patients (33.0%), including 108 (35.6%) in the breakfast skipping group and 435 (32.4%) in the breakfast consuming group. In fully adjusted models accounting for 5-aminosalicylic acid and immunosuppressant use, breakfast skipping was associated with higher odds of steroid withdrawal (OR 1.52, 95% CI 1.08-2.14). These findings suggest that meal timing may influence sustained remission in UC.