Faecal calprotectin testing in UK general practice: a retrospective cohort study using The Health Improvement Network database

Background Faecal calprotectin (FC) testing to detect inflammatory bowel disease (IBD) was recommended for use in UK general practice in 2013. The actual use of FC testing following the national recommendations is unknown. Aim To characterise the use of FC testing for IBD in UK general practice. Design and setting A retrospective cohort study of routine electronic patient records from The Health Improvement Network database from UK general practice. Method The study included 6 965 853 adult patients (aged ≥18 years), between 2006 and 2016. FC test uptake, the patients tested, and patient management following testing were characterised. Results A total of 17 027 patients had 19 840 FC tests recorded. The mean age of tested patients was 44.2 years. The first FC tests were documented in 2009. FC test use was still increasing in 2016. By 2016, 66.8% (n = 493/738) of practices had started FC testing. About one-fifth (20.7%, n = 1253/6051) of tests were carried out in patients aged ≥60 years. Only 7.8% (n = 473/6051) of the FC test records were preceded by symptoms eligible for FC testing. Only 3.1% (n = 1720/55 477) of patients with eligible symptoms have received FC testing since the national recommendations were published. There was only a small number of patients with symptoms, FC test, and a IBD diagnosis. In total, 71.3% (n = 1416/1987) of patients with a positive and 47.7% (n = 1337/2805) with a negative FC test were referred or further investigated. Conclusion Uptake of FC testing in clinical practice has been slow and inconsistent. The indication of non-compliance with national recommendations may suggest that these recommendations lack applicability to the general practice context.