High-rise buildings and neurologically favorable outcome after out-of-hospital cardiac arrest

Background The number of people living in high-rise buildings has recently been increasing in Japan, and delayed transport time by emergency-medical-service (EMS) personnel from higher floors could lead to lower survival after out-of-hospital cardiac arrest (OHCA). However, there are no clinical studies assessing the association between the floor where patients reside and neurologically favorable outcome after OHCA. Methods This was a prospective, population-based study conducted in Osaka City, Japan that enrolled adults aged >=18 years suffering an OHCA of cardiac origin before EMS arrival between 2013 and 2014. The primary outcome measure was one-month survival with neurologically favorable outcome. We divided OHCA patients into the following groups: those residing on >=3 floors (the high floor group) and < 3 floors (the low floor group). Multiple logistic regression analysis was used to assess factors associated with neurologically favorable outcome. Results A total of 2979 patients were eligible for analysis. Of them, 1885 (62.3%) occurred below the third floor and 1094 (37.4%) occurred at or above the third floor. The proportion of neurologically favorable outcome after OHCA was significantly lower in the high floor group than in the low floor group (2.7% [30/1094] versus 4.8% [91/1885], P = 0.005). In a multivariate analysis, neurologically favorable outcome after OHCA was significantly lower in the high floor group than in the low floor group (adjusted odds ratio, 0.59 [95% confidence interval, 0.37–0.96]). Conclusions In this population, one-month survival with neurologically favorable outcome from OHCA was lower in the high floor group than in the low floor group.