Pre-existing comorbidity modify emergency room visit for out-of-hospital cardiac arrest in association with ambient environments.

BACKGROUND:This study evaluated risks of emergency room visit (ERV) for out-of-hospital cardiac arrest (OHCA) in 2005-2011, among patients with cardiologic and metabolic syndromes (CMS), in association with ambient environments. METHODS:Pooled and area-specific weather related cumulative six-day (lags 0 to 5) relative risks (RRs) and confidence intervals (CIs) of ERV for OHCA were evaluated for CMS cases, using distributed lag nonlinear models and multivariate meta-analytical second-stage model in association with the daily average temperatures and daily concentrations of air pollutants. RESULTS:ERV risk increased as average temperature dropped to