Table 4.
Subgroup analyses comparing the joint intervention of reducing SBP by 20% if above 140mmHg and quitting smoking to the natural course
| Subgroup | Stroke | Dementia | ||||||
|---|---|---|---|---|---|---|---|---|
| Risk under natural course (95% CI) | Risk under joint intervention (95% CI) | Risk ratio (95% CI) | Risk difference (95% CI) | Risk under natural course (95% CI) | Risk under joint intervention (95% CI) | Risk ratio (95% CI) | Risk difference (95% CI) | |
| Complete cohort | 10.3 (9.3, 11.5) | 8.5 (7.2, 9.9) | 0.83 (0.71, 0.94) | −1.8 (−3.1, −0.6) | 9.2 (8.2, 10.3) | 9.6 (8.0, 11.6) | 1.05 (0.92, 1.20) | 0.4 (−0.7, 2.0) |
| Age below 65 (n = 2303) | 6.3 (5.0, 7.9) | 4.7 (3.3, 6.4) | 0.75 (0.56, 0.98) | −1.6 (−2.7, −0.2) | 4.0 (3.2, 5.7) | 4.2 (3.0, 6.1) | 1.04 (0.73, 1.37) | 0.2 (−1.0, 1.4) |
| Age between 65 and 80 (n = 2627) | 14.0 (12.6, 15.8) | 11.9 (9.6, 14.5) | 0.85 (0.71, 1.00) | −2.2 (−4.3, 0.0) | 13.8 (12.4, 15.6) | 14.2 (12.0, 17.3) | 1.03 (0.87, 1.20) | 0.4 (−1.8, 2.9) |
| Women (n = 2824) | 9.3 (8.1, 10.9) | 7.7 (6.1, 10.3) | 0.83 (0.71, 1.02) | −1.6 (−2.9, 0.3) | 11.2 (9.7, 12.7) | 10.1 (8.4, 12.3) | 0.91 (0.73, 1.05) | −1.1 (−3.4, 0.5) |
| Men (n = 2106) | 11.6 (10.2, 13.5) | 9.4 (7.5, 12.3) | 0.81 (0.67, 1.01) | −2.2 (−4.0, 0.1) | 7.0 (6.0, 8.9) | 9.8 (7.2, 13.0) | 1.40 (1.12, 1.64) | 2.8 (0.8, 4.5) |
| Without hypertension medication at baseline (n = 3570) | 9.0 (8.1, 10.6) | 7.0 (5.8, 9.1) | 0.78 (0.66, 0.94) | −2.0 (−3.3, −0.5) | 8.8 (8.0, 10.2) | 9.9 (7.7, 11.8) | 1.12 (0.95, 1.27) | 1.1 (−0.4, 2.4) |
| Free of heart disease at baseline (n = 4406) | 9.9 (9.1, 10.9) | 8.2 (6.8, 10.1) | 0.83 (0.70, 0.99) | −1.6 (−2.9, −0.1) | 8.8 (8.0, 10.0) | 9.2 (7.6, 11.1) | 1.05 (0.9, 1.16) | 0.4 (−0.9, 1.6) |
SBP systolic blood pressure (mmHg)
Estimates were based using the parametric g-formula with fixed covariates: age, sex, education, systolic blood pressure, history of diabetes and history of heart disease at baseline; and time-varying covariates: visit process, smoking status, systolic blood pressure, body mass index, hypertension medication, total cholesterol and diagnosis of diabetes, heart disease, Parkinson disease, Parkinsonism, transient ischemic attack, dementia or cancer