Table 8.
Effect Modification by Flavonoid Intake on the Association Between PM2.5 Exposure and HRV, Adjusted for Total Fruit and Vegetable Intake, and Adjusted for Mean TLR2 Methylation
| HRV Measure | Original Model (N=513)* | Adjusted for Total Fruit and Vegetable Intake (N=482)* | Adjusted for Mean TLR2 Methylation (N=423)* | ||||||
|---|---|---|---|---|---|---|---|---|---|
| % Change* | 95% CI | P for Interaction | % Change* | 95% CI | P for Interaction | % Change* | 95% CI | P for Interaction | |
| HR | −0.18 | −1.32 to 0.98 | 0.76 | −0.30 | −1.48 to 0.90 | 0.62 | 0.89 | −0.72 to 2.52 | 0.30 |
| rMSSD | 1.17 | −7.38 to 10.51 | 0.79 | 0.67 | −8.45 to 10.7 | 0.89 | 0.07 | −11.28 to 12.87 | 0.99 |
| SDNN | 2.98 | −3.43 to 9.81 | 0.37 | 2.77 | −3.88 to 9.88 | 0.42 | 2.28 | −6.49 to 11.87 | 0.62 |
| LF | 14.63 | 0.27 to 31.03 | 0.05 | 15.81 | 0.50 to 33.45 | 0.04 | 10.48 | −8.39 to 33.24 | 0.30 |
| HF | 8.98 | −6.93 to 27.62 | 0.28 | 7.65 | −9.17 to 27.59 | 0.40 | 7.65 | −12.28 to 32.10 | 0.48 |
HF indicates high‐frequency power (0.15 to 0.4 Hz); HR, heart rate; HRV, heart rate variability; LF, low‐frequency power (0.04 to 0.15 Hz); PM2.5, particulate matter with aerodynamic diameter <2.5 μm; rMSSD, root mean square of successive differences; SDNN, standard deviation of normal‐to‐normal intervals; TLR2, Toll‐like receptor 2.
Results were adjusted for age; body mass index; total caloric intake; total vitamin C intake; total fiber intake; fasting glucose level; hypertension; smoking status; alcohol consumption; physical exercise; household income; the use of calcium channel blocker, β‐blocker, and angiotensin‐converting enzyme inhibitor; room temperature; outdoor apparent temperature; season; weekday, and visit date.
In addition to all the covariates in the original model except total vitamin C and fiber intake, results were adjusted for total fruit and vegetable intake.
In addition to all the covariates in the original model, results were adjusted for mean TLR2 methylation, and the interaction between mean TLR2 methylation and PM2.5 concentration.
The additional percent change in HRV associated with 10 μg/m3 PM2.5 concentration, compared to participants with 1 interquartile range lower flavonoid intake level.