Resource utilization and outcomes in patients with atrial fibrillation: a case control study.

BACKGROUND: Atrial fibrillation (AF) is the most common sustained disorder of cardiac rhythm. Various new anticoagulation and antiarrythmic treatments are being investigated for the treatment of AF. Before novel treatments can be used widely in actual clinical practice, the cost effectiveness of such novel treatments may need to be determined. OBJECTIVE: The objectives of the study were to describe resource utilization for AF and control patients, and estimate the incidence of mortality. METHODS: This case control study evaluated 6 months of primary and secondary care resource utilization and mortality rates for patients within the period 01 April 2001 to 31 March 2006. Cases included 15 373 adults with a record of AF in the General Practice Research Database (GPRD) within the study period. The index date was randomly selected between 6 months after the AF record and end of data collection. Cases were matched to controls by age, gender, general practice and time. RESULTS: AF patients had significantly higher resource utilization than controls. Resource utilization increased with greater National Institute for Clinical Excellence (NICE) stroke risk strata (graded as low, moderate or high based on associated risk factors). Both current warfarin and aspirin users had higher resource utilization than control patients. Resource utilization remained high amongst AF patients who discontinued therapy. The mortality rate was significantly higher in AF patients than controls, deaths due to circulatory system disease were increased 4-fold and cancer deaths were doubled. All-cause and circulatory mortality rates, as well as rates of clinical outcomes, were related to the NICE stroke risk schema. CONCLUSIONS: There was large heterogeneity in resource utilization between AF patients, although overall, this was still higher than controls without AF. Higher resource utilization was evident in patients at higher risk of stroke, and remained where antithrombotic therapy was discontinued. The mortality risk in AF was increased substantially, both for cardiovascular and non-cardiovascular causes of death, indicating a large unmet medical need.