Table 2.
Heart Rate Variability in subjects at the beginning of and after 5-h exposure in a chamber with or without filtration of inlet air from an urban street
| Exposure | Particle filtered air | Non-filtered air | ||
|---|---|---|---|---|
| After entry | After 5 h | After entry | After 5 h | |
| SDNN, ms | 68 (41;115) | 48 (27;82) | 60* (31;116) | 52 (26;99) |
| HFn | 28 (16;55) | 31 (10;58) | 30 (11;69) | 29 (13;54)* |
| LFn | 68 (27;89) | 66 (30;90) | 66 (27;90) | 70 (37;86)# |
| LF/HF ratio | 2.4 (0.6;5) | 2.1 (0.5;10) | 2.3 (0.4;8) | 2.5 (0.8;7) |
*p < 0.05 (decrease), #p = 0.027 (increase), SDNN: standard deviation of the beat-to-beat interval; HFn: High frequency, normalised units; LFn: Low frequency, normalized units. Values are medians (5th;95th percentiles).