Abstract
INTRODUCTION: Facing Mount Tai in the south and the Yellow River in the north, Zibo District is an important petrochemical base in China. The effect of air pollution on cardiovascular diseases (CVDs) in Zibo was unclear. METHODS: Daily outpatient visits of common CVDs including coronary heart disease (CHD), stroke, and arrhythmia were obtained from 2019 to 2022 in Zibo. Air pollutants contained fine particulate matter (PM(2.5)), inhalable particulate matter (PM(10)), nitrogen dioxide (NO(2)), sulfur dioxide (SO(2)), ozone (O(3)), and carbon monoxide (CO). Distributed lag non-linear models (DLNM) including single-pollutant model in single-day (lag0-lag7) and cumulative-days (lag01-lag07), concentration-response curve, subgroup analysis, and double-pollutant model were utilized to examine the relationships of daily air pollutants on CHD, stroke, and arrhythmia. Meteorological factors were incorporated to control confounding. RESULTS: In single-pollutant model, NO(2) was positively associated with CHD, stroke and arrhythmia, with the strongest excess risks (ERs) of 4.97% (lag07), 4.71% (lag07) and 2.16% (lag02), respectively. The highest ERs of PM(2.5) on CHD, stroke and arrhythmia were 0.85% (lag01), 0.59% (lag0) and 0.84% (lag01), and for PM(10), the ERs were 0.37% (lag01), 0.35% (lag0) and 0.39% (lag01). SO(2) on CHD was 0.92% (lag6), O(3) on stroke was 0.16% (lag6), and CO on CHD, stroke, and arrhythmia were 8.77% (lag07), 5.38% (lag01), 4.30% (lag0). No threshold was found between air pollutants and CVDs. The effects of ambient pollutants on CVDs (NO(2)&CVDs, PM(2.5)&stroke, PM(10)&stroke, CO&stroke, CO&arrhythmia) were greater in cold season than warm season. In double-pollutant model, NO(2) was positively associated with CHD and stroke, and CO was also positively related with CHD. CONCLUSION: Ambient pollutants, especially NO(2) and CO were associated with CVDs in Zibo, China. And there were strong relationships between NO(2), PM(2.5), PM(10), CO and CVDs in cold season.