Acute heart failure in subtropical climates: clinical characteristics, management, and outcomes in the Canary Islands versus continental Spain - the CANAR-ICA study results

Objective. To determine whether there are differences in the clinical characteristics, management, and outcome of episodes of acute heart failure (AHF) in residents of the Canary Islands, where the climate is subtropical, and episodes in continental Spain. Methods. Cases were identified in the registry for Epidemiology of Acute Heart Failure in Emergency Departments and categorized as in the Canary Islands or continental Spain. Data for 38 demographic, baseline, clinical, and therapeutic variables were extracted. We analyzed statistics for in-hospital and 30-day mortality, long hospital stay (more than 7 days), and a composite outcome after discharge (revisits or death within 30 days). The results for island and continental patients were compared and adjusted for between-group differences. Results. A total of 18 390 patients were studied, 697 islanders (3.8%) and 17 673 continental patients (96.2%). Comparisons showed that the islanders were younger; more often women; and more likely to have hypertension, diabetes, and a prior AHF episode. Their New York Heart Association functional class was also likely to be higher. However, their rates of dyslipidemia, valve disease, and functional dependence were lower, and they were also less likely to be on renin-angiotensin system blockers. Although the severity of cardiac decompensation was similar in island and continental patients, the islanders received more intravenous treatments in the emergency department and were admitted less often. The adjusted risk of a long hospital stay was higher for the islanders (odds ratio [OR], 2.36; 95% CI, 1.52-3.02) but their risk for mortality and the composite outcome did not differ: in-hospital mortality, OR 0.97 (95% CI, 0.68-1.37); 30-day mortality, OR, 0.9 (95% CI, 0.67-1.27); and the post-discharge composite, OR, 1.19 (95% CI, 0.93-1.53). Conclusions. Baseline patient characteristics and clinical management of AHF episodes differ between the subtropical region and those in southern continental Europe. Hospitalization was required less often, but hospital stays were longer.