Treatment with oral anticoagulant drugs restrained from patients with atrial fibrillation: An assessment in a geographically well-defined catchment area.

BACKGROUND: Atrial fibrillation (AF) affects about 3.2% of the adult population in the western world and incurs an annual stroke risk of 4.5%. The use of oral anticoagulant (OAC) drugs significantly reduces this risk. OAC drugs seem to be under-utilized, but little is known about why their use is restrained in routine clinical management. The aim of this study was to assess this issue and, from these data, to estimate the proportion of patients with AF in a general population who were eligible for treatment with OAC drugs.

DESIGN: Retrospective study of medical records.

METHODS: The study included all identified patients with AF in a well-defined catchment area of 65,532 people, among whom 1616 (3.2%) had documented AF. Of the patients with AF, 588 (36%) were originally reported not to be receiving OAC drugs. The patient-responsible physicians (n = 24) were requested to complete a standardized questionnaire to assess the reason for restraining the use of OAC drugs for each individual patient.

RESULTS: Of the 588 patients originally reported not to be receiving OAC drugs, eight were shown to be using OAC drugs and seven were lost to follow up. Thus the reason for restraining OAC drugs was finally assessed in 573 patients. The primary reasons were: lack of indication, 26%; declined general condition, 14%; a history of bleeding, 12%; assumed poor compliance, 11%; repeated falls, 6%; and reason unknown, 9%.

CONCLUSIONS: This is, to our knowledge, the first study to assess the reasons for restraining the use of OAC drugs in a geographically well-defined population including all hospital-based and non-hospital-based healthcare. Applying CHA2DS2-VASc and new strategies for OAC drugs to our study data indicated that between 72 and 88% of all patients with AF are eligible for treatment with OAC drugs.