Variation in route to diagnosis of heart failure in primary care in England: analysis of a retrospective cohort between 2010 and 2013. (November 2018) - Kim, Dani
Abstract: Background: Heart failure is common (affecting at least 550 000 people in the UK) and costly, with frequent admission to hospital and high mortality. Diagnosis remains difficult in primary care. We have demonstrated previously that few patients follow a route to diagnosis aligned with National Institute for Health and Care Excellence (NICE) guidelines, suggesting lack of implementation of evidence-based guidelines and variability in provision of care. Therefore, we explored variation in the route to diagnosis of heart failure in primary care by key patient factors and general practice. Methods: We analysed a retrospective cohort of 13 897 patients (349 general practices) diagnosed with heart failure in England between 2010 and 2013 from a linked primary care database. The primary outcome was receipt of care aligned with NICE guidelines within 6 months of initial presentation with symptoms of heart failure. Explanatory variables were key patient demographics, comorbidities, symptom type, consultation history, and diagnosis route. We used logistic regression to investigate association, funnel plots to visualise variation between practices, and multilevel logistic regression to estimate the intracluster correlation coefficient (ICC). Findings: Patient characteristics significantly associated with the primary outcome were age group, deprivation level, chronic pulmonary disease, presenting symptom type, consultation received for symptom, and diagnosis route (sex or myocardial infarction were not associated). The strongest predictor for care aligned with NICE guidelines was presentation with breathlessness only (odds ratio 3·07, 95% CI 2·40–3·93). The funnel plot showed wide variation in the proportion of patients following NICE guidelines between practices, identifying 45 (13%) outliers. Eight general practices (2%) fell above the upper limit of 3SD of the funnel distribution, and 31 (9%) above the limit of 2SD. Only six practices (2%) fell below the lower limit of 2SD. There was statistically significant variation between practices, and practices accounted for 9% of this variability (ICC 8·6%, p<0·0001). Interpretation: A strong association of certain patient characteristics with likelihood of following the recommended NICE pathway suggests potential targets to improve diagnosis and management of heart failure in primary care. We found significant variation in care between general practices, which merits further investigation of practice-level factors. Our findings have potential to better inform implementation of current guidelines, and they demonstrate a useful approach to investigating the implementation of evidence-based guidelines that highlight novel areas for improvement. Funding: Supported by the Imperial National Institute for Health Research (NIHR) Biomedical Research Centre and the NIHR Collaboration in Leadership in Applied Health and Care Northwest London.