A multi-pollutant air quality health index for assessing mortality risk of ischemic heart disease in Jinan, China

To investigate the exposure-response relationship between air pollutants and mortality risk of ischemic heart disease (IHD) in Jinan, establish a tailored Air Quality Health Index (AQHI) for IHD mortality risk assessment, and evaluate the performance of this integrated index in quantifying the effects of air pollutants on IHD mortality. A distributed lag non-linear model was employed to quantitatively evaluate the exposure-response relationship and lag effects between air pollutants and IHD mortality risk. An AQHI for IHD was developed, and its predictive performance for excess risk ( ER ) of IHD mortality was compared with that of the conventional Air Quality Index (AQI). Results of the cumulative lag analysis showed that for each 10 µg/m³ increase in the concentrations of PM 2.5 (lag03), NO 2 (lag05), SO 2 (lag07), and O 3 (lag07), and each 1 mg/m³ increase in CO (lag04), the ER of IHD mortality increased by 0.914% (95% CI : 0.059–1.776), 1.744% (95% CI : 0.005–3.512), 13.802% (95% CI : 7.398–20.588), 1.285% (95% CI : 0.355–2.223), and 12.240% (95% CI : 2.735–22.625), respectively. When AQHI and AQI increased by one interquartile range (IQR), AQHI showed a consistently stronger effect on IHD mortality risk than AQI. Subgroup analyses confirmed that in male, female, age ≥ 65 years, married, other marital status, junior high school or below, warm season and cold season subgroups, the AQHI-associated ER per IQR increment was consistently higher than that of AQI. Air pollutants have significant lag effects on IHD mortality. Compared with the conventional AQI, the locally established Jinan-specific AQHI shows better applicability for air quality classification and stronger predictive power for IHD mortality risk in the local population.