Abstract Background Cities are characterized by distinct microclimates shaped by urban structure density and environmental conditions, such as limited green spaces and poor ventilation. These urban bioclimatic variations contribute to environmental stressors, such as heat island effect and air pollution, potentially impacting cardiovascular health. However, the independent role of bioclimate situation in early-onset myocardial infarction (MI) risk and prognosis remains unexplored. Methods This study included all consecutive patients aged ≤55 years presenting with STEMI who were admitted to a heart center between 2015 and 2022 and resided in our city. The Geoportal was used to evaluate the bioclimatic conditions of patients' residential areas, categorizing them into two groups—favorable and unfavorable—based on urban structure density and green space availability. Long-term MACCE outcomes were assessed over an 8-year follow-up period using multivariable survival analysis, adjusted for age, sex, cardiovascular risk factors, and MI severity. Results A total of 644 young patients with STEMI were included. 395 resided in areas with a favorable bioclimatic situation, while 249 were from areas with an unfavorable situation. Young MI-patients from areas with unfavorable bioclimatic conditions had a lower burden of cardiovascular risk factors, including lower rates of diabetes (12.1% vs. 21.3%, p=0.003), obesity (30.1% vs. 38.5%, p=0.03), and family history of CAD (22.1% vs. 31.1%, p=0.012). They also had fewer cardiovascular risk factors overall (2.58 ± 1.07 vs. 2.88 ± 1.10, p0.001) and a lower calculated 10-year cardiovascular risk (LIFE CVD: 0.039 ± 0.023 vs. 0.050 ± 0.029, p0.001) (table 1). Despite this, there were no differences in age at first MI (48.5 ± 6.5 vs. 48.3 ± 5.5, p=0.614) and the MI severity was comparable, as assessed by Killip classification, left ventricular ejection fraction, number of diseased coronary arteries, and in-hospital outcomes, including mortality (all p 0.5) (table 1). In a multivariable survival analysis, bioclimatic situation emerged as a significant and independent predictor of long-term MACCE. Patients residing in areas with an unfavorable bioclimatic situation had a significantly higher risk of MACCE compared to those in favorable areas (HR: 1.88, 95% CI: 1.15–3.08, p=0.01), independent of age, gender, family history, traditional risk factors, socioeconomic status, and infarction severity (figure 1). Conclusion Young STEMI patients from areas with higher urban density and limited green spaces had a lower prevalence of traditional cardiovascular risk factors compared to those in favorable bioclimatic areas. However, despite these differences, age at first MI and MI severity were similar. Unfavorable bioclimatic environment was independently associated with a significantly higher risk of long-term MACCE. These findings highlight unfavorable bioclimatic conditions as an independent cardiovascular risk factor.Table 1 Figure 2
Kerniss et al. (Sat,) studied this question.