Association between inflammatory bowel disease and psychiatric morbidity and suicide: A Swedish nationwide population-based cohort study with sibling comparisons.

BACKGROUND AND AIMS Inflammatory bowel disease (IBD) is linked to psychiatric morbidity, but few studies have assessed general population comparators. We aimed to investigate the risk of psychiatric morbidity and suicide in adult-onset IBD patients. METHODS Nationwide population-based cohort study in Sweden (1973-2013). We studied the risk of psychiatric disorders and suicide in 69,865 adult-onset IBD patients (ulcerative colitis, UC: n=43,557; Crohn's disease, CD: n=21,245; and IBD-unclassified: n=5063) compared to 3,472,913 general population references and 66,292 siblings. RESULTS During a median follow-up of 11 years, we found 7,465 (10.7%) first psychiatric disorders in IBD (incidence rate, IR/1000 person-years 8.4) and 306,911 (9.9%) in the general population (IR 6.6), resulting in 1.8 extra psychiatric morbidity per 100 patients followed-up for 10 years and a hazard ratio (HR) of 1.3 (95% confidence interval, 95%CI=1.2-1.3). The highest risk of overall psychiatric morbidity was seen in the first year after IBD diagnosis (HR=1.4, 95%CI=1.2-1.6) and in patients with extraintestinal manifestations (HR=1.6, 95%CI=1.5-1.7). Psychiatric morbidity was more common in all IBD subtypes (HRs 1.3 to 1.5). An increased risk of suicide attempts was observed among all IBD types (HRs=1.2 to 1.4), whereas completed suicide was explicitly associated with CD (HR=1.5) and elderly-onset (diagnosed at the age of >60 years) IBD (HR=1.7). CONCLUSION Adult-onset IBD was associated with an increased risk of psychiatric disorders and suicide attempts. Psychological follow-up should be provided to patients with IBD, especially those with extraintestinal manifestations and elderly-onset IBD. This follow-up should transpire within the first year after IBD diagnosis.