Work

Short-term association between ambient air pollution and heart rate variability: results from the population-based KORA S4 and FF4 studies

Year: 2025

Type: article

Abstract: Background Ambient air pollution is a major risk factor for CVDs, and a plausible mechanism is speculated to be alteration of autonomic nervous system (ANS) function. Yet, the short-term effects of air pollution on heart rate variability (HRV), a measure of ANS balance are inconsistent. Objective This study aimed to evaluate the short-term effects of ambient PM 2.5 and NO 2 on cardiovascular autonomic function, and to determine vulnerable subgroups and temporal trends from repeated HRV and HR measurements over 14 years in the KORA cohort. Methods We analyzed data from 4,032 participants in KORA S4 (1999–2001) and 1,912 in KORA FF4 (2013–2014). Air pollution data were from fixed monitoring stations, and HRV indices were derived from 5-minute ECG recordings. Generalized additive models (GAMs) and generalized additive mixed models (GAMMs) were used to assess associations. Results In S4, each IQR increase in PM 2.5 at the 14-day moving average was associated with a 2.32% (95% CI: − 4.41, − 0.19) decrease in SDNN and a 1.20% (95% CI: 0.16, 2.26) increase in HR. By contrast, KORA FF4 showed opposite associations, with a 0.86% (95% CI: 0.02, 1.70) increase in SDNN at lag 4 for PM 2.5 . Effect modifications by age and smoking status were observed in S4. No statistically significant associations were found in the longitudinal analysis, however, the observed trends were consistent with the effects identified in S4. Conclusion Short-term exposure to PM 2.5 and NO 2 impacts cardiac autonomic function, with varying effects across study waves due to aging, smoking, medication, and lower pollution levels. Even at low ambient concentrations, these exposures impaired autonomic function via inflammation and oxidative stress, underscoring the importance of stringent air quality standards and lifestyle interventions in reducing cardiovascular risk.

Source: Particle and Fibre Toxicology

DOI: 10.1186/s12989-025-00645-6