Nationwide temporal trend analysis of reperfusion therapy utilization and mortality in acute ischemic stroke patients in Japan.

This study aimed to elucidate nationwide trends in reperfusion therapy utilization and subsequent 30-day mortality in acute ischemic stroke patients in Japan. The analysis focused on intravenous recombinant tissue plasminogen activator (IV rt-PA) and endovascular thrombectomy (EVT). Using health insurance claims data, we calculated the age- and sex-adjusted monthly number of acute ischemic stroke patients who received IV rt-PA and/or EVT in Japan from April 2010 to March 2016, and investigated the 30-day all-cause mortality rates after undergoing these therapies. Through an interrupted time-series analysis, we examined the: (1).. trends prior to extension of the IV rt-PA therapeutic time window from 3 hours to 4.5 hours in September 2012, (2).. changes that occurred immediately after the extension, and (3).. differences in trends between the pre- and post-extension periods. During the study period, 69,920 patients with acute ischemic stroke (mean age ± standard deviation: 74.9 ± 12.0 years; 41.4% women) received IV rt-PA and/or EVT. The age- and sex-adjusted number of patients receiving IV rt-PA monotherapy increased immediately after the time window extension (  < .001), but did not change during the pre- ( = .90) and post-extension ( = .58) periods. In contrast, the number of patients receiving EVT with or without IV rt-PA continuously increased during the pre-extension period ( < .001), and further increased during the post-extension period ( <.001); however, this number decreased immediately after the extension ( < .001). There were no significant changes in 30-day all-cause mortality during the pre- ( = .40) and post-extension ( = .64) periods, as well as immediately after the extension ( = .53). The extension of the IV rt-PA therapeutic time window and progressively widespread use of EVT in Japan have increased the number of acute ischemic stroke patients eligible for reperfusion therapy. These trends were not accompanied by a higher risk of post-reperfusion mortality.