Chronic comorbidities associated with inflammatory bowel disease: prevalence and impact on healthcare costs in Switzerland

Objective Inflammatory bowel disease (IBD) was shown to be associated with a variety of chronic comorbidities. We aimed to evaluate the frequency of 21 chronic conditions and compared frequencies in IBD and non-IBD populations. Further, healthcare costs of those (additional) chronic conditions were calculated. Patients and methods A total of 4791 IBD patients, who were insured at Helsana Insurance Group in 2014, were compared with 1114638 individuals without IBD. Entropy balancing was performed to create balanced samples. Chronic conditions were identified by means of the updated Pharmacy-based Cost Group model. Multivariate log-transformed linear regression modeling was performed to estimate the effect of the morbidity status (non-IBD +none, +1, +2, and +3 or more chronic conditions) on the healthcare costs. Results Overall, 78% of IBD patients had at least one comorbidity, with a median of three comorbidities. Largest differences between individuals with and without IBD were found for rheumatologic conditions, acid-related disorders, pain, bone diseases, migraines, cancer, and iron-deficiency anemia, whereas no significant differences between the two groups were found for diabetes, dementia, hyperlipidemia, glaucoma, gout, HIV, psychoses, and Parkinson's disease after adjustments for a variety of covariates. Each increase in the morbidity status led to increased healthcare costs; rheumatologic conditions, acid-related disorders, and pain as the most frequent comorbidities more than doubled total costs in IBD patients. Conclusion We found a considerably high prevalence of concomitant chronic diseases in IBD patients. This was associated with considerably higher healthcare costs, especially in the outpatient setting. Copyright (C) 2017 Wolters Kluwer Health, Inc. All rights reserved.