Table 4.
Subgroup Analysis of Attenuated HRR and Risk of All‐Cause Mortality
| Variable | Attenuated HRR vs Fast HRR | Per 10 bpm Decrement in HRR | ||||||
|---|---|---|---|---|---|---|---|---|
| N | HR (95% CI) | I2 (%) | P heterogeneity | N | HR (95% CI) | I2 (%) | P heterogeneity | |
| Recovery time point | ||||||||
| 2 minutes | 2 | 1.50 (1.07, 2.08) | 20.1 | 0.26 | 2 | 1.14 (1.06, 1.23) | <1 | 0.45 |
| 1 minute | 6 | 1.74 (1.54, 1.96) | <1 | 0.77 | 3 | 1.06 (0.92, 1.23) | 59.2 | 0.09 |
| Exercise stress testing workloads | ||||||||
| Maximal | 6 | 1.72 (1.53, 1.93) | <1 | 0.57 | 3 | 1.15 (1.08, 1.23) | <1 | 0.73 |
| Submaximal | 1 | 1.22 (0.71, 2.09) | NA | NA | 1 | 0.93 (0.80, 1.08) | NA | NA |
| Other | 1 | 1.59 (1.04, 2.42) | NA | NA | 1 | 1.08 (0.91, 1.27) | NA | NA |
| Treadmill | ||||||||
| Yes | 5 | 1.74 (1.54, 1.97) | <1 | 0.64 | 3 | 1.09 (0.94, 1.27) | 71.9 | 0.03 |
| No | 3 | 1.49 (1.19, 1.88) | <1 | 0.45 | 2 | 1.09 (0.98, 1.22) | <1 | 0.87 |
| Country | ||||||||
| USA | 5 | 1.74 (1.54, 1.97) | <1 | 0.64 | 4 | 1.09 (0.98, 1.22) | 58.6 | 0.07 |
| Others | 3 | 1.49 (1.19, 1.88) | <1 | 0.45 | 1 | 1.10 (0.96, 1.27) | NA | NA |
| Sex | ||||||||
| Men | 2 | 1.50 (1.07, 2.12) | 22.2 | 0.26 | 1 | 1.10 (0.96, 1.27) | NA | NA |
| Women | 2 | 1.86 (1.21, 2.85) | <1 | 0.68 | 1 | 1.16 (1.07, 1.26) | NA | NA |
| Combined | 4 | 1.73 (1.53, 1.96) | <1 | 0.52 | 3 | 1.06 (0.91, 1.22) | 56.5 | 0.10 |
| Adjusting for: | ||||||||
| Smoking | ||||||||
| Yes | 5 | 1.79 (1.47, 2.19) | <1 | 0.64 | 3 | 1.06 (0.93, 1.22) | 69.1 | 0.04 |
| No | 3 | 1.62 (1.39, 1.89) | 15.4 | 0.31 | 2 | 1.14 (1.02, 1.27) | <1 | 0.46 |
| VO2max | ||||||||
| Yes | 2 | 1.86 (1.21, 2.87) | <1 | 0.66 | 1 | 1.08 (0.91, 1.28) | NA | NA |
| No | 6 | 1.67 (1.49, 1.87) | <1 | 0.41 | 4 | 1.10 (0.99, 1.21) | 58 | 0.07 |
| At least 3 metabolic factors | ||||||||
| Yes | 6 | 1.75 (1.46, 2.10) | <1 | 0.73 | 3 | 1.06 (0.93, 1.22) | 69.1 | 0.04 |
| No | 2 | 1.59 (1.26, 2.01) | 57.3 | 0.13 | 2 | 1.14 (1.02, 1.27) | <1 | 0.46 |
HR indicates hazard ratio; HRR, heart rate recovery; NA, not applicable; VO2max, maximal oxygen consumption.