Nonoptimal Temperature Is Associated With Higher Atrial Fibrillation Hospitalizations in China

Figure 1. Distribution of Participating Centers in China Atrial Fibrillation Program Map showing locations of the final 802 centers included in the study and the initial 866 registered centers in the China Atrial Fibrillation Center Program.

Figure 2. Exposure-Response Curves of Ambient Temperature and AF Admissions in China (A) Exposure-response curves for daily mean temperature and hospital admissions for atrial fibrillation in mainland China, (B) northern China, and (C) southern China. Solid lines represent cumulative relative risk, with areas indicating 95% CIs. Vertical lines show the MHT, extreme cold (1st percentile), and extreme heat (99th percentile). Temperature distributions are shown at the bottom. AF = atrial fibrillation; MHT = minimum hospitalization temperature.

Figure 3. Relative Risks of AF Admissions With Extreme Cold and Heat Temperatures by Subgroup The figure shows the relative risks with 95% CIs of daily hospital admissions for atrial fibrillation in association with extreme cold temperature (1st percentile of temperature, left panel) and extreme heat temperature (99th percentile of temperature, right panel), stratified by age, sex, and comorbidities. aThe Pinteraction values were obtained from Z-tests comparing the differences between the effect estimates of different subgroups. bThe risk factors refer to having any item included in the CHA2DS2-VASc score beyond sex (congestive heart failure, hypertension, age ≥65 years, diabetes, prior stroke/transient ischemic attack/thromboembolism, vascular disease). RR = relative risks; TIA = transient ischemic attack; other abbreviations as in Figure 2.

Central Illustration. Ambient Temperature and Hospital Admissions for Atrial Fibrillation in China The solid lines are the cumulative relative risk of hospital admissions for atrial fibrillation. Vertical lines indicate the minimum hospitalization temperature (MHT), extreme cold, and extreme heat (1st and 99th percentiles of temperature series, respectively). The lower part shows the temperature distributions. AF = atrial fibrillation; RWS-CAF = Chinese Atrial Fibrillation Real-World Study.