Trends of the Incidence of Ischemic Stroke Thrombolysis over Seven Years and One-Year Outcome: A Population-Based Study in Joinville, Brazil

BACKGROUND: In a population-based setting, we aimed to measure the incidence trends of ischemic stroke (IS) thrombolysis, thrombolysis times, proportion of symptomatic intracerebral hemorrhage (sICH), 30-day case fatality and functional outcomes. We also compared the 12-month functional status between thrombolyzed and nonthrombolyzed patients. METHODS: Using data from the Joinville Population-Based Stroke Registry, we prospectively ascertained a cohort of all thrombolyses done in Joinville citizens, Southern Brazil, from 2005 to 2011. For the definition of sICH we used European Cooperative Acute Stroke Study (ECASS) II criteria. RESULTS: Over 7 years, 6% (220/3,552) of all IS were thrombolyzed. The thrombolysis incidence increased from 1.4 [95% confidence interval (CI), 0.6-2.9] in 2005 to 9.8 (7.3-12.9) per 100,000 population in 2011 (p < 0.0001). The thrombolysis incidence age-adjusted to the world population in 2011 was 11 (8.2-14.3) per 100,000. Only 30% (50/165) were thrombolyzed within 1 h of arrival at hospital. In 7 days, 6.4% (14/220) had sICH and 57% (8/14) of those died. In the 2009-2011 period, a favorable functional outcome [modified Rankin scale (mRS) 0-1] at 12 months among patients who received thrombolysis was more frequent [mRS 0-1; 36% (38/107)] than among patients who did not receive thrombolysis [mRS 0-1; 24% (131/544); p = 0.016]. The logistic regression showed that thrombolyzed IS patients had a more favorable outcome (mRS 0-1; HR 2.13; 95% CI, 1.2-3.7; p < 0.016) than nonthrombolyzed patients. CONCLUSION: In a population setting of a middle income country, the thrombolysis incidence and outcomes were similar to those of other well-structured services. After 1 year, patients thrombolyzed in the 4.5-hour time window had a better outcome. More than proportions, rates provide additional information and could be used to benchmark services against others.