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Phenotype Submission - Ulcerative Colitis

Cohort Definition Name : Earliest event of Ulcerative colitis

Contributor name : Joel Swerdel’

Contributor OrcId : 0000-0002-6976-2594’

Logic Description : Earliest occurrence of Ulcerative Colitis indexed on diagnosis date, for the first time in history cohort exit is the end of continuous observation

Recommended study application : target

Assertion statement : This cohort definition was executed on at least one real person-level observational health data source and resulted in a cohort with at least 1 person.

Target Clinical Description : Ulcerative Colitis (UC) is a chronic immune-mediated inflammatory disease which affects the large intestine, extending proximally from the rectum, and causes continuous mucosal inflammation. Age at presentation peaks between 15-30 years with a second peak between 50-80 years [1]. The overall incidence is estimated to be 1.2-20.3 per 100,000 py and the prevalence 7.6-245 per 100,000 py [2]. Risk factors include age, Jewish ethnicity, smoking, dysbiosis, diet (high fat, processed meats), and a family history of UC.

Evaluation conclusion : We developed a prevalent cohort definition for Ulcerative colitis (UC) using a concept set of six concepts which incorporated all those found from the literature review and from the analysis of PHOEBE and orphan concepts in cohort diagnostics. The algorithm retrieves subjects from all 11 databases tested. We developed a more specific cohort requiring a second diagnosis code for UC in the time period 31-365 days after index. This cohort improves the specificity of the algorithm albeit at the expense of sensitivity as determined by PheValuator. The 31-365 day period was determined to improve specificity compared to a 1-30 day or 1-60 day post-index second code requirement. The significant loss in sensitivity, however, precludes its use as a target population. for this definition, sensitivity ranged from about 67% in MDCD to about 98% in JMDC while positive predictive value ranged from about 64% in MDCD to about 95% in JMDC

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Thanks @Azza_Shoaibi and @jswerdel for sharing this Ulcerative Colitis phenotype. I plan to re-use it as a nesting indication for our HowOften effort in OHDSI2023.

In reviewing this, I note that under the PHOEBE recommender, there are a few other ‘complications due to UC’ that aren’t included in the conceptset. Examples: ‘Intestinal obstruction due to ulcerative colitis’, ‘Fistula of intestine due to ulcerative colitis’, ‘arthropathy in ulcerative colitis’. I wonder if there was a specific reason to not include these concepts. Or perhaps this is another example of vocabulary shift, since I see that you’ve included the concept of ‘Complication due to ulcerative colitis’ + descendants, and it would have seemed like perhaps some of these would have been expected to fall under that umbrella. (if that were the case, then I wonder whether in the phenotype library, we should try to capture the vocabulary version for which the algorithm was created, so that we can see when we’re working off a different version, so that we know to check consistency).

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Imported to the OHDSI Phenotype Library. It may be expected to be found with id = 860 in the next release. Thank you

What’s the one example you are alluding to?