Assessing the relationship of major cardiovascular emergencies and environmental factors in Germany

Environmental factors such as air pollution, noise, extreme temperatures and artificial light at night are associated with acute cardiovascular events. This study assesses the suitability of district-level environmental exposure metrics across Germany, including estimates derived from inhabited areas only, and examines how these regionally variable factors relate to acute ST-segment elevation myocardial infarction (STEMI), non–ST-segment elevation myocardial infarction (NSTEMI), acute limb ischaemia, acute stroke, acute pulmonary embolism, and aortic rupture across all German districts. This retrospective observation study relied on year-specific hospitalization rates obtained from the German Hospital Quality Registry. It compiles a district-level summary of the hospitalization rates and sixteen environmental variables on vegetation, artificial light or land surface temperature derived by open-source satellite data, air and noise pollution data from the European Environment Agency, and climate information from the German Weather Service (DWD). We utilized a generalized additive model (GAM) framework to analyse cardiovascular emergencies while adjusting for population size, spatial structure, socioeconomic factors and temporal trends. A total of 3,784,737 acute cardiovascular emergencies were recorded. Before adjustment, 56 exposure–outcome associations were statistically significant, whereas only 12 remained significant after adjustment. Noise exposure was the only environmental variable showing robust associations with acute limb ischemia (RR = 2.47, 95% CI: 1.53–3.96), aortic rupture (RR = 1.47, 95% CI: 1.12–1.91), and pulmonary embolism (RR = 1.27, 95% CI: 1.02–1.58) after full adjustment. The remaining significant associations were predominantly characterized by non-linear exposure–response patterns, often without a consistent monotonic increase or decrease in risk across the exposure range. Across most exposure–outcome combinations, adjustment for socioeconomic, land-cover, and spatial factors substantially altered both the magnitude and shape of the estimated associations. Most associations between environmental exposures and acute cardiovascular emergencies were substantially attenuated after adjustment for socioeconomic and spatial factors. Environmental noise emerged as the most consistent exposure associated with acute vascular emergencies.