The Epidemiology of Bile Acid Diarrhea in Denmark [Letter]

Dear editor

We were very impressed with the article entitled “The Epidemiology of Bile Acid Diarrhea in Denmark”. The results of this research have advantages, namely: 1) Identify individuals with bile acid diarrhea (BAD) in Denmark using data from the national registry, 2) Identify individuals suffering from BAD based on ICD10 diagnosis codes or SeHCAT test followed by prescription of bile acid binders within a period of 365 days, 3) Show differences in the frequency of BAD diagnosis in different regions of Denmark, 4) Provide information on the characteristics of individuals suffering from BAD, including lower education level, lower income, and higher number of contacts with health services compared to a comparable control group, 5) Track the use of liraglutide as a potential therapy for BAD.¹

However, we have also discovered several limitations that need to be corrected in the future, namely: 1) The use of a combination of SeHCAT testing and prescription of bile acid binders over a 365-day period to identify individuals with BAD may not include the entire population who actually have BAD. Some individuals with BAD may not have undergone the SeHCAT test or received alternative treatment, so they will not be identified in this study, 2) The ICD10 diagnosis codes for BAD will only be used starting in 2021, so the validity and consistency of using these codes prior to that year is limited, 3) Although the study tracked the use of liraglutide as a potential therapy for BAD, it did not provide information on the effectiveness or safety of liraglutide in the treatment of BAD, 4) The study findings cannot be directly generalized to populations outside Denmark due to differences in health systems, clinical practices, and population characteristics.

To obtain better results, we recommend that further research be carried out by 1) Further validate the definition of BAD used in this study by comparing it with SeHCAT test results and other clinical data to ensure that it covers the entire population with BAD, 2) Conduct prospective studies involving direct data collection from individuals with BAD, including information on symptoms, diagnostic test results, response to treatment, and quality of life, to gain a more in-depth understanding of the characteristics and experiences of individuals with BAD,² 3) Conduct further analysis of risk factors associated with BAD, including the relationship with other comorbid conditions, including associations with other comorbid conditions, genetic factors, and environmental factors, to better understand the pathophysiology and epidemiology of BAD,³ 4) Conduct comparative studies comparing the effectiveness and safety of various therapies for BAD, including bile acid binders and other therapies such as liraglutide, to help guide optimal treatment options.