Urban Air Pollution and Cardiovascular Health: A Study of PM2.5 and CVD Morbidity in a Metropolitan City, Karachi (Pakistan)

Ambient air pollution, particularly fine particulate matter (PM2.5), poses significant health risks, especially concerning cardiovascular diseases (CVDs). This study assesses the association between PM2.5 exposure and CVD hospital admissions (HAs) and emergency room (ER) visits in Karachi, Pakistan. Daily PM2.5 samples were collected from four Karachi sites (Makro, Karachi University, Keamari, and Malir) between October 2009 and June 2011. CVD morbidity data, including HAs and ER visits, were gathered from major hospitals. A single-pollutant model was employed to evaluate associations between PM2.5 levels and CVD outcomes, adjusting for meteorological variables and other potential confounders. PM2.5 concentrations and CVD morbidity were significantly associated across all sites Stratification by age and gender revealed stronger associations among males and individuals aged 40 and above. Exposure to elevated levels of PM2.5 in Karachi was significantly associated with increased CVD HAs and ER visits, with the highest association found between PM2.5 exposure and arrhythmias. The study underscores the need for effective air quality management policies and interventions to reduce PM2.5 levels. Karachi’s high PM2.5 levels demand urgent attention from regulatory agencies and public health professionals to implement interventions that mitigate air pollution and protect vulnerable populations.