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 36 participants who had not welded 2 weeks before the study
| AC* | DC | |
|---|---|---|
| Parameter | (95% CI) | (95% CI) |
| Models | ||
| No lag | 1.54 (0.96 to 2.32) | −1.18 (−0.60 to −1.79) |
| 1 h lag† | 0.97 (0.13 to 1.81) | −0.89 (−0.09 to −1.70) |
| 2 h lag† | 0.66 (−0.94 to 1.87) | −0.37 (1.09 to −1.83) |
| 3 h lag† | 0.29 (−2.58 to 2.60) | −0.18 (2.57 to −2.15) |
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 1.54 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 hour lag model also adjusts for PM2.5 measurements in the preceding hour before the exposure time point of interest.