The Epidemiology of Bile Acid Diarrhea in Denmark.

Objective: Bile acid diarrhea (BAD) is a socially debilitating disease with frequent bowel movements, urgency, and fecal incontinence as the main symptoms. It is caused by excessive bile acid levels in the colon and is most commonly treated with bile acid sequestrants. It is estimated that 1-2% of the population suffers from the disease, but only a fraction of these are properly diagnosed with the gold standard 75selenium-homotaurocholic acid (SeHCAT) test. Here, we use nationwide registries to describe the demographic characteristics of individuals suffering from BAD in Denmark. Methods: Since the International Classification of Diseases diagnosis code for BAD was not used until 2021, we identified the BAD population by referral to SeHCAT testing followed by a prescription of a bile acid sequestrant (colestyramine, colestipol or colesevelam) within 365 days. The study period was from 2003 to 2021. Results: During the study period, a total of 5264 individuals with BAD were identified with large differences between the five regions in Denmark. The number of prescriptions of colestyramine and colesevelam, the number of SeHCAT tests, and the number of individuals diagnosed with BAD increased during the study period. The BAD population had more co-morbidities and more health care contacts as well as lower levels of education and income compared with age- and sex-matched controls from the general population. Conclusion: Using the Danish registries, we identified a BAD population, which seems to be inferior in health care and socio-economic parameters compared with the Danish general population.