Table 4

Main effect of PM2.5 (mg/m3) on acceleration capacity (AC; ms) and deceleration capacity (DC; ms) with adjustment for hourly pre-exposures from the linear mixed effect response-lagged models with 48 participants

Parameter(95% CI)(95% CI)
 No lag1.46 (1.00 to 1.92)−1.00 (−0.53 to −1.46)
 1 h lag†0.81 (0.30 to 1.32)−0.70 (−0.14 to −1.26)
 2 h lag†1.00 (0.13 to 1.87)0.45 (0.52 to −1.42)
 3 h lag†0.41 (−1.65 to 2.46)−0.12 (2.48 to −2.71)
  • Bold values indicate significant associations (p<0.05). Models are adjusted for age, smoking status, actively smoking, secondhand smoke exposure, time of day and season of ECG reading, and baseline AC or DC.

  • *AC is measured on a negative scale; therefore, a 1 mg/m3 increase in PM2.5 results in a decrease in AC by 1.46 ms (on a negative scale) for the association without any lag.

  • †Lagged models adjust for exposure time points before the lags. For example, a 1 h lag model also adjusts for PM2.5 measurements in the preceding hour before the exposure time point of interest.