Introduction: Irritable bowel syndrome (IBS) is a disorder of gut-brain interaction (DGBI), and associated co-morbidities worsen quality of life. Research concerning IBS co-morbidities in different racial/ethnic groups is very sparse. This study aimed to determine the prevalence rates of co-morbidities and possible differences in a multiracial/ethnic IBS cohort. Methods: Based on ICD-9-coded IBS diagnosis, 740 outpatients (≥18 years) were included in this retrospective study at Boston Medical Center. Demographics and ICD-9-coded co-morbidities were extracted from electronic records. Descriptive statistics and multiple logistic regression were used for data analyses. Results: The most prevalent co-morbidities in this IBS cohort included gastroesophageal reflux disorder (GERD) (30%), depression (27%), anxiety (23%), (chronic obstructive pulmonary disease) COPD/asthma (16%), and obesity (10%). GERD was more prevalent in Hispanics and Blacks (p = 0.0005), and non-ulcer dyspepsia (NUD) was more prevalent in Blacks and Asians (p = 0.003). Higher rates of diabetes mellitus type 2 (DMT2) (p = 0.0003) and depression (p = 0.03), but not anxiety (p = 0.9), were present in Blacks and Hispanics. GERD was significantly associated with Hispanics (p = 0.003), dependent on age, overweight, and obesity. NUD was significantly associated with Blacks (p = 0.01) and Asians (p = 0.006), independent of sex, age, and BMI. Cancer of the thyroid, ovaries, and testis occurred at a five-fold higher rate than expected. Conclusions: Significant racial/ethnic differences exist for IBS co-morbidities in this study cohort, including depression, DMT2, GERD, and NUD. Certain cancers were found to be more frequent in this IBS sample as compared with the general population.
Keywords: cancer; co-morbidities; epidemiology; irritable bowel syndrome; racial and ethnic diversity.