P4137Initiation of oral anticoagulation therapy in atrial fibrillation patients with schizophrenia: a nationwide cohort study

• Published in: European heart journal 2019-10, Vol.40 (Supplement_1)
• Main Authors: Hojen, A A, Larsen, T B, Hjortshoej, S P, Riahi, S, Lip, G Y H, Soegaard, M
• Format: Article
• Language: English
• ISSN: 0195-668X; 1522-9645
• DOI: 10.1093/eurheartj/ehz745.0709

Abstract Background Schizophrenia is associated with poor anticoagulation control and prognosis in patients with atrial fibrillation (AF). However, little is known about initiation of oral anticoagulation therapy (OAC) in this patient population. Purpose To examine the initiation of OAC in AF patients with schizophrenia. Methods We linked nationwide Danish health registries to identify all patients with schizophrenia who were diagnosed with incident AF, 2000–2016. These patients were matched 1:5 on sex and age to incident AF patients without schizophrenia. Using a pseudo-value regression approach, we calculated risk difference (RD) of a redeemed OAC prescription at 1 year follow-up, by schizophrenia status. We conducted multivariate regression of pseudovalues, adjusting for the effect of the individual components of the CHA2DS2-VASc and HAS-BLED scores, and repeated the analyses with stratification according to CHA2DS2-VASc score. Results Among 592 patients with schizophrenia who developed incident AF, 26.6% initiated OAC within the first year following AF diagnosis, compared with 53.2% of age and sex matched comparisons without schizophrenia, corresponding to a RD of −26.4 (95% CI −30.4 to −22.4). OAC initiation remained lower among AF patients with schizophrenia even after adjusting for CHA2DS2-VASc and HAS-BLED factors (adjusted RD −24.5, 95% CI: −28.5 to −20.4)). OAC initiation was lower in AF patients with schizophrenia across all levels of the CHA2DS2-VASc score (Table). Table 1. OAC initiation Oral anticoagulation therapy (%) Risk difference Schizophrenia No Schizophrenia Schizophrenia vs. No schizophrenia (95% CI) Overall 26.6 53.2 −26.6 (−30.6 to 22.6) CHA2DS2-VASc   Score 0 16.7 40.1 −23.4 (−32.6 to −14.3)   Score 1 23.1 45.9 −22.8 (−31.6 to −14.0)   Score 2 26.7 59.8 −33.1 (−42.1 to −24.1)   Score 3 31.9 59.3 −27.3 (−36.8 to −17.9)   Score 4 28.6 57.1 −28.5 (−39.7 to −17.3)   Score 5 30.4 57.7 −27.2 (−41.9 to −12.5)   Score ≥6 33.3 62.2 −28.9 (−45.9 to −11.9) Risks and RD at 1 year follow-up by schizophrenia status. Conclusion Initiation of OAC was substantially lower among AF patients with schizophrenia compared to sex and age matched AF patients without schizophrenia, independent of stroke and bleeding risk. These findings emphasize the need for vigilant follow-up in this patient population.