Lower socioeconomic status is associated with an increased prevalence of comorbid anxiety and depression among patients with irritable bowel syndrome: results from a multicenter cohort.

Background/Aims: Anxiety and depression are common comorbid psychiatric disorders in IBS patients, but the population-level determinants influencing these comorbidities in IBS patients are poorly understood. We sought to determine whether there was an association between comorbid affective disorders and socioeconomic status among irritable bowel syndrome (IBS) patients. Methods: We assembled a retrospective cohort of 1074 IBS patients with comorbid Generalized Anxiety Disorder (GAD) and/or Major Depressive Disorder (MDD) seen at two tertiary referral centers between 2007 and 2015. IBS patients with comorbid GAD and/or MDD were matched 3:1 by age, sex, and race to controls with IBS and no history of comorbid GAD and/or MDD. Socioeconomic status was approximated by patient zip codes. Results: IBS patients in the lowest socioeconomic group were more likely to be diagnosed with GAD and/or MDD compared to controls (OR = 1.38, p = .0004). The median average per capita income for comorbid GAD/MDD IBS patient cohort was also significantly lower than the control IBS patient cohort ($39,880.50 vs. $41,277.00, p = .02). Conclusions: Among IBS patients, the presence of comorbid Generalized Anxiety Disorder and/or Major Depressive Disorder is associated with lower socioeconomic status and lower average per capita income. These findings speak to a biopsychosocial model of illness, which should be considered by clinicians in the care of IBS patients.