TABLE 4.
Hazard ratios for primary and secondary endpoints by age class
| Endpoint | PP variable |
Age class (years) | Ratio of HR at >70 years to HR at 50–60 years |
P value of HR trend for age greater than 50 years |
||||
|---|---|---|---|---|---|---|---|---|
| ≤40 | 40–50 | 50–60 | 60–70 | >70 | ||||
| Number at risk | 2635 | 2028 | 2470 | 2263 | 2452 | |||
| Total mortality | N | 42 | 102 | 322 | 736 | 1744 | ||
| PP | 0.83 [0.45–1.51] (0.54) | 0.97 [0.68–1.38] (0.87) | 1.35 [1.16–1.57] (0.0001) | 1.18 [1.09–1.29] (0.0001) | 1.09 [1.05–1.14] (0.00008) | 0.81 | 0.003 | |
| N = 2946 | elPP | 0.80 [0.47–1.35] (0.40) | 0.98 [0.71–1.35] (0.90) | 1.20 [1.03–1.40] (0.018) | 1.20 [1.10–1.30] (0.00003) | 1.09 [1.05–1.14] (0.00001) | 0.91 | 0.014 |
| stPP | 1.07 [0.60–1.90] (0.81) | 0.97[0.70–1.35] (0.87) | 1.32 [1.13–1.53] (0.0004) | 1.04[0.95–1.14] (0.36) | 1.02 [0.97–1.07] (0.38) | 0.77 | 0.061 | |
| CV events | N | 26 | 89 | 283 | 502 | 1193 | ||
| PP | 0.63 [0.30–1.31] (0.22) | 1.00 [0.69–1.44] (1.00) | 1.50 [1.29–1.75] (<0.000001) | 1.28 [1.16–1.41] (0.000001) | 1.14 [1.09–1.20] (<0.000001) | 0.76 | 0.0006 | |
| N = 2093 | elPP | 0.56 [0.29–1.08] (0.086) | 0.95 [0.68–1.35] (0.78) | 1.41 [1.22–1.63] (0.000004) | 1.27[1.16–1.40] (0.000001) | 1.13 [1.08–1.19] (<0.000001) | 0.80 | 0.0001 |
| stPP | 1.12 [0.57–2.23] (0.74) | 1.08 [0.77–1.51] (0.66) | 1.28 [1.09–1.50] (0.002) | 1.11[1.00–1.23] (0.061) | 1.06 [1.00–1.12] (0.045) | 0.83 | 0.44 | |
| CV mortality | N | 7 | 17 | 104 | 235 | 739 | ||
| PP | 0.51 [0.12–2.22] (0.37) | 0.51 [0.21–1.25] (0.14) | 1.58 [1.21–2.03] (0.0006) | 1.44 [1.25–1.65] (<0.000001) | 1.16 [1.09–1.24] (0.000005) | 0.73 | 0.018 | |
| N = 1102 | elPP | 0.58 [0.17–2.00] (0.39) | 0.42 [0.17–1.01] (0.054) | 1.50 [1.16–1.94] (0.002) | 1.46[1.29–1.67] (<0.000001) | 1.15 [1.08–1.22] (0.000004) | 0.77 | 0.0015 |
| stPP | 0.56 [0.11–2.78] (0.48) | 0.99 [0.46–2.14] (0.98) | 1.26 [0.97–1.54] (0.082) | 1.09 [0.94–1.26] (0.27) | 1.06 [0.99–1.14] (0.080) | 0.84 | 0.88 | |
| Coronary events | N | 12 | 51 | 153 | 211 | 505 | ||
| PP | 0.36 [0.12–1.1] (0.074) | 0.95 [0.58–1.56] (0.83) | 1.50 [1.22–1.84] (0.00009) | 1.23 [1.07–1.43] (0.0045) | 1.20 [1.11–1.29] (0.000001) | 0.80 | 0.13 | |
| N = 932 | elPP | 0.38 [0.14–0.99] (0.047) | 0.88 [0.55–1.40] (0.59) | 1.43 [1.19–1.73] (0.0002) | 1.25 [1.08–1.43] (0.002) | 1.17 [1.09–1.25] (0.00001) | 0.82 | 0.031 |
| stPP | 0.84 [0.27–2.64] (0.76) | 1.11 [0.71–1.74] (0.64) | 1.23 [1.00–1.52] (0.049) | 1.03 [0.89–1.20] (0.68) | 1.11[1.02–1.20] (0.011) | 0.90 | 0.63 | |
| Stroke events | N | 10 | 30 | 99 | 232 | 475 | ||
| PP | 3.06 [1.03–9.09] (0.044) | 1.40 [0.76–2.58[ (0.28) | 1.51 [1.14–1.99[ (0.004) | 1.44 [1.24–1.67] (0.000002) | 1.18 [1.09–1.28] (0.00008) | 0.78 | 0.007 | |
| N = 846 | elPP | 1.86 [0.67–5.21] (0.24) | 1.20 [0.66–2.18] (0.55) | 1.35 [1.03–1.78] (0.031) | 1.35 [1.17–1.56] (0.00006) | 1.19 [1.11–1.28] (0.000001) | 0.88 | 0.066 |
| stPP | 3.99 [1.20–13.3] (0.024) | 1.29 [0.75–2.22] (0.36) | 1.37 [1.02–1.83] (0.033) | 1.26 [1.07–1.48) (0.0044) | 1.00 [0.92–1.10] (0.92) | 0.73 | 0.005 | |
| Stroke mortality | N | 3 | 3 | 31 | 69 | 190 | ||
| PP | 0.93 [0.08–11.5] (0.96) | 0.61 [0.10–3.54] (0.58) | 1.85 [1.18–2.92] (0.008) | 1.48 [1.12–1.95] (0.005) | 1.19 [1.03–1.36] (0.015) | 0.64 | 0.12 | |
| N = 296 | elPP | 0.94 [0.10–9.14] (0.96) | 0.63 [0.10–3.99] (0.63) | 1.69 [1.04–2.72] (0.033) | 1.54 [1.20–1.97] (0.0007) | 1.23 [1.10–1.38] (0.0004) | 0.73 | 0.12 |
| stPP | 0.97 [0.05–19.0] (0.98) | 0.77 [0.13–4.64] (0.78) | 1.45 [0.91–2.30] (0.12) | 0.97 [0.70–1.33] (0.84) | 0.93 [0.80–1.08] (0.36) | 0.64 | 0.23 | |
Data are the mean adjusted hazard ratio (HR) with [95% confidence interval] and P value (in parentheses) for given PP variable, endpoint, and age class. HR expresses the relative risk associated with a 1SD increment in a PP variable calculated for all participants. SD was 10.0, 8.3, and 6.22mmHg for PP, elPP, and stPP, respectively (see Table 1). Data in bold font mark hazard ratios for which P is less than 0.05. The PP components, elPP and stPP, were included in the same Cox model. Adjustments included cohort, sex, age, BMI, smoking and drinking, serum total cholesterol, antihypertensive drug intake, history of cardiovascular disease and diabetes mellitus, and mean 24-h DBP and heart rate. N is the number of events. CV, cardiovascular; y, years; PP, 24-h mean pulse pressure; elPP, and stPP are, respectively, the ‘elastic’ and ‘stiffening’ PP components described in Fig. 1 and the formulas for its calculations are provided (Supplemental Methods, http://links.lww.com/HJH/C43). P value of hazard ratio trend for age over 50 years was derived from an interaction term between the PP variable and age class added to the Cox models.