Blood pressure trajectories in relation to cardiovascular mortality: The Rancho Bernardo Study
The added value of blood pressure (BP) trajectories for predicting cardiovascular disease (CVD) is currently unknown. We investigated the association of systolic BP (SBP) trajectories with CVD and all-cause mortality and compared these associations with those of average SBP, taking antihypertensive medication into account. Data from 762 participants of the Rancho Bernardo Study were used. SBP from five examinations (maximum) from 1984 to 2002 was used; mortality data were obtained from 2002 to 2013. SBP trajectories were derived using group-based trajectory modelling. Cox proportional hazards analysis was used to investigate associations of trajectories and average SBP with CVD and all-cause mortality, adjusted for age, sex, cholesterol, smoking, diabetes and antihypertensive medication. Mean baseline age was 65.7 years, and 67% were women. Four trajectories were identified, in which mean SBP increased by 5–12 mm Hg during 10 years. The highest trajectories were associated with two to three times greater CVD mortality and 1.5 times greater all-cause mortality risk, compared with the lowest trajectory. Each 20 mmHg increment in average SBP was associated with 1.4 times greater CVD mortality risk and 1.2 times all-cause mortality risk. Associations were not modified by antihypertensive medication (P-interaction>0.10). SBP trajectories were not superior to average SBP in predicting CVD and all-cause mortality. In the general middle-aged and older population of the Rancho Bernardo study, SBP trajectories provided no added value to average SBP in predicting CVD and all-cause mortality. Long-term average SBP levels and trajectories were significant predictors of CVD and all-cause mortality, irrespective of prescribed antihypertensive medication (which in the 1980s-1990s mainly were diuretics and β-blockers).