Prior Dual Antiplatelet Therapy and Mortality After Intracerebral Hemorrhage: A Danish Nationwide Cohort Study

Background Limited data support the link between dual antiplatelet therapy (DAPT) and adverse outcome among patients with intracerebral hemorrhage. This study aimed to investigate the association between prior use of DAPT and mortality after intracerebral hemorrhage. Methods Patients with first‐ever intracerebral hemorrhage on current APT at the time of admission, were identified and followed 180 days after admission through the Danish nationwide registries. Prior exposure to DAPT or single APT (SAPT) was established through the Danish National Prescription Registry. Inverse probability of treatment weighting was used to control for confounding. Results A total of 5800 patients were on antiplatelet therapy. 5535 (95.4%) were on SAPT, and 265 (4.6%) were on DAPT. Compared with patients on SAPT, patients on DAPT more commonly had a history of ischemic stroke or transient ischemic attack (134 [50.6%] versus 2393 [43.2%]), ischemic heart disease (172 [64.9%] versus 1561 [28.2%]), congestive heart failure (57 [21.5%] versus 505 [9.1%]) or chronic kidney disease (25 [9.4%] versus 205 [3.7%]). The 180‐day cumulative mortality rate was 52.6% for patients on DAPT and 45.6% for patients on SAPT ( P =0.004). After weighting and compared with SAPT, prior use of DAPT was associated with a 43% higher mortality risk at day 1 (weighted risk ratio 1.43, 95% CI, 1.13–1.82). Higher early mortality among patients on DAPT was found to be the driving force behind the higher day 180 mortality in this group. Conclusions Among patients with intracerebral hemorrhage, prior DAPT was found to be associated with a higher mortality compared with SAPT.