Tobacco use in Crohn's disease patients and association with disease outcomes in the United States Medicaid population, 2010-2019.

Background and Aim: To identify demographic factors associated with tobacco use in Crohn's disease (CD) patients in the US Medicaid population and examine how tobacco use affects disease outcomes. Methods: We included Medicaid-eligible patients who had ≥1 ICD code for CD, and 1 year of eligibility before and after the initial encounter. We used ICD codes to identify tobacco use with respect to the time of diagnosis and used logistic regression to identify the association between age, sex, and race with tobacco use at any point before diagnosis and after diagnosis, and determine the association of tobacco use before and after diagnosis on disease outcomes. Results: We identified 98 176 eligible patients; 74.5% had no documented use of tobacco and 25.5% used tobacco at some point; 21.1% had used tobacco before their CD diagnosis and 11.8% had used tobacco after diagnosis. The population that used tobacco had a higher proportion of women, those who were White, non-Hispanic, and those in their middle ages (21-60) than the group that did not use tobacco. Tobacco use before diagnosis resulted in higher risk of hospitalization and surgery (OR: 1.85 and 1.36, respectively). Conclusion: Within the CD Medicaid population, tobacco use is more common in women than men, which differs from the general population, which is possibly a result of using diagnostic codes rather than survey data. Smoking cessation efforts should especially be directed at younger people who are at risk for CD, due to increased risk for more adverse outcomes among those who use tobacco before diagnosis.

Burden of Crohn's Disease in the United States Medicaid Population, 2010-2019.

BACKGROUND & AIMS: Twenty-five percent of the United States population is enrolled in Medicaid. Rates of Crohn's disease (CD) have not been estimated in the Medicaid population since the Affordable Care Act expansion in 2014. We aimed to estimate the incidence and prevalence of CD by age, sex, and race. METHODS: We identified all 2010-2019 Medicaid CD encounters using codes from the International Classification of Diseases, Clinical Modification versions 9 and 10. Individuals with ≥2 CD encounters were included. Sensitivity analyses were performed on other definitions (eg, ≥1 CD encounter). Incidence required ≥1 year of Medicaid eligibility prior to first CD encounter date (2013-2019). We calculated CD prevalence and incidence using the entire Medicaid population as the denominator. Rates were stratified by calendar year, age, sex, and race. Poisson regression models examined CD-associated demographic characteristics. We compared demographics and treatments of the entire Medicaid population with the multiple CD case definitions using percent and median. RESULTS: A total of 197,553 beneficiaries had ≥2 CD encounters. The CD point prevalence per 100,000 persons rose from 56 (2010) to 88 (2011) to 165 (2019). CD incidence per 100,000 person-years was 18 (2013) and 13 (2019). Higher incidence and prevalence rates correlated with female, white, or multiracial beneficiaries. Prevalence rates rose in later years. Incidence decreased over time. CONCLUSIONS: From 2010 to 2019, Medicaid population CD prevalence increased while incidence decreased from 2013 to 2019. Overall Medicaid CD incidence and prevalence ranges align with prior large administrative database studies.

A Systematic Review of Crohn's Disease Case Definitions in Administrative or Claims Databases.

BACKGROUND: We sought to review Crohn's disease (CD) case definitions that use diagnosis, procedure, and medication claims. METHODS: We searched PubMed and Embase from inception through January 31, 2022, using terms related to CD, inflammatory bowel disease, administrative claims, or validity. Each article was scrutinized by 2 authors independently screening and abstracting data. Collected data included participant characteristics, case definition characteristics, and case definition validity. When diagnostic accuracy was provided for multiple case definitions, we extracted the case definition selected by the authors. All diagnostic accuracy characteristics were captured. RESULTS: We identified 30 studies that evaluated a case definition using claims data to identify CD patients. The most common case definition included counts of diagnosis codes (57%) followed by a combination of diagnosis codes and medications (20%). All but 1 study validated the case definition with a medical chart review. In 2 studies, the patient's primary care provider completed a survey to confirm disease status. The positive predictive value of the case definitions ranged from 18% (≥1 code at a single U.S. health plan) to 100% (≥1 code plus a relevant prescription at a U.S. hospital). More complex case definitions (eg, ≥1 code + prescription or ≥2 codes) had lower variability in positive predictive value (≥80%) and specificity (≥85%) than the ≥1 code requirement. CONCLUSIONS: Health services researchers should validate case definitions in their research cohorts. When such validation cannot be performed, we recommend using a more complex case definition. Studies without a validated CD case definition should use sensitivity analyses to confirm the robustness of their results.

This systematic review of Crohn's disease (CD) case definitions identified that complex case definitions such as ≥1 diagnosis code + ≥1 prescription had desirable diagnostic accuracy properties.