Socioeconomic inequality in oral anticoagulation therapy initiation in patients with atrial fibrillation with high risk of stroke: a register-based observational study

• Published in: BMJ open Vol. 11; no. 5; p. e048839
• Main Authors: Lunde, Elin Danielsen, Joensen, Albert Marni, Fonager, Kirsten, Lundbye-Christensen, Søren, Johnsen, Søren Paaske, Larsen, Mogens Lytken, Lip, Gregory YH, Riahi, Sam
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group LTD 31.05.2021; BMJ Publishing Group
• Series: Original research
• Subjects: Age; Anticoagulants; Cardiac arrhythmia; Cardiovascular Medicine; Classification; Clinical practice guidelines; Codes; Diabetes; Disease; Education; Heart failure; Hypertension; Observational studies; Patients; Population; Secondary education; Socioeconomic factors; Stroke; Thromboembolism; Transient ischemic attack; Womens health; Denmark
• ISSN: 2044-6055; 2044-6055
• DOI: 10.1136/bmjopen-2021-048839

ObjectiveThe study aimed to examine the association between socioeconomic factors (SEFs) and oral anticoagulation (OAC) therapy and whether it was influenced by changing guidelines. We hypothesised that inequities in initiation of OAC reduced over time as more detailed and explicit clinical guidelines were issued.DesignRegister-based observational study.SettingsAll Danish patients with an incident hospital diagnosis of atrial fibrillation (AF), aged ≥30 years old and with high risk of stroke from 1 May 1999 to 2 October 2015 were included. Absolute risk differences (RD) (95% CI) were used to measure the association.Participants154 448 patients (mean age 78.2 years, men 47.3%).ExposureEducation, family income and cohabiting status were the SEFs used as exposure.OutcomeA prescription of OAC within −30 to +90 days of baseline (incident AF).ResultsDuring 2002–2007, the crude RD of initiation of OAC for men with high education was 14.9% (12.8 to 16.9). Inequality reduced when new guidelines were published, and in 2013–2016 the crude RD was 5.6% (3.5 to 7.7). After adjusting for age, the RD substantially reduced. The same pattern was seen for cohabiting status, while inequality was smaller and more constant for income.ConclusionPatients with low income, low education and living alone were associated with lower chance of being initiated with OAC. For education and cohabiting status, the crude difference reduced around 2011, when more detailed clinical guidelines were implemented in Denmark. Our results indicate that new guidelines might reduce inequality in OAC initiation and that new, high-cost drugs increase inequality.