The association between meteorological events and acute heart failure: new insights from ASCEND-HF.

Introduction: Given the rising prevalence of heart failure (HF), our objective is to explore the relationships between meteorological events and acute HF (AHF) globally.

Methods: We used data from 30 countries participating in the ASCEND-HF trial. Parameters including temperature were normalized by location for the 37 days prior to the HF event. Meteorological events were classified as a change that occurred <10% compared to baseline. The 7 days prior to the HF event was subdivided: T1: the day of and -1 day; T2: 2 and 3 days; T3: 4 and 5 days; and T4: 6 and 7 days. Results are reported as ratios of observed to expected weather events at the time of AHF presentation.

Results: From 7141 patients, median age was 67 (IQR 56-76) with 66% male patients and 60% of patients with ischemic cardiomyopathy. In T1, temperatures were warmer than expected with 10% fewer decreases in average [OR 0.91 95% CI (0.83-0.98)] and minimum [OR 0.90 95% CI (0.82-0.97)] temperature. In T2, temperatures were again warmer than expected with an excess number of increases in maximum [OR 1.18 95% CI (1.06-1.30)] and average [OR 1.21 95% CI (1.10-1.32)] temperature. In T4 temperatures were cooler than baseline with fewer increases [OR 0.84 95% CI (0.74-0.95)] in average temperature.

Conclusions: Meteorological fluctuations appear most relevant in the 3 days (T1 and T2) prior to the HF hospitalization with temperature demonstrating a bidirectional relationship with AHF. Continued validation of biometeorological trends in HF will contribute to healthcare system planning globally.