Reges O. Hypertension. 2021 Feb;77(2):347-356.

Hypertension is a major risk factor for CVD and previous studies have exhibited generally higher longevity between individuals with beneficial BP. But, the information is limited on the effect of BP on proportion of life lived free of disorder, or healthspan and the correlation of cumulative exposure of SBP with compression of CVD morbidity, that is, living longer and healthy life expectancy with a shorter period with morbidity, has not previously been analysed. Thus, Reges O, et al., conducted a study to evaluate the correlation of cumulative SBP in middle age with long-term risk of CVD and with healthy longevity, by individual-level pooled data from 5 racially and ethnically diverse US community based CVD groups with an average of about 30 years of follow-up.

Total 11 502 individuals, aged 45 to 60 years, with no history of CVD, and with ≥3 visits with SBP analysis across the 10 years prior to the index date from the 38 054 individuals in FHS, FOS, CARDIA, ARIC, and MESA. In the 10 years preindex date, a median of 4.0 visits with BP estimations (ranged from 3 to 6 visits) was done by each individual. Theses available analyses were spread across a median of 9.1 years (range: 7.2–10 years). The mean (SD) of the Cum10ySBP was 1212 (154) mm Hg×years, estimated as the area under the 10-years SBP curve, reflecting an average annual exposure of 121.2 mmHg per year.

Greater Cum10ySBP was correlated with shorter overall survival in which participants died an average of 4.1 years earlier and also showed an earlier onset of CVD by 5.4 years. This means that the proportion of life lived free of disease was greater in those with lower Cum10ySBP, in addition to a longer overall lifespan, showed reduction in CVD morbidity and increase in CVD free survival (Figure 1).

Figure 1: Overall survival, CVD free survival and time spent with CVD after index date.*,†

This flow chart shows the overall survival, CVD free survival and time spent with CVD after the index date according to 10 years cumulative systolic blood pressure quartiles. SBP indicates systolic blood pressure. *Average age (years) at index date was 55.5, 55.8, 56.1, and 56.4 y for quartile 1, quartile 2, quartile 3, and quartile 4, respectively. †Mean life expectancy was 82.2, 81.2, 80.1, and 78.1 y for quartile 1, quartile 2, quartile 3, and quartile 4, respectively.

Unadjusted hazards models showed substantial correlation among Cum10ySBP and incidence of CVD, CHD, stroke, CHF, and all-cause mortality, and greater risk with the increase in the cumulative SBP. Models adjusted for sociodemographic characteristics, cardiovascular risk factors, and index systolic BP showed correlations of 10-year cumulative systolic BP (per 130 mm Hg×year change, the threshold for stage-1 hypertension) with CVD (HR, 1.28 [95% CI, 1.20–1.36]), coronary heart disease (HR, 1.29 [95% CI, 1.19–1.40]), stroke (HR, 1.33 [95% CI,1.20–1.47]), heart failure (HR, 1.12 [95% CI, 1.02–1.23]), and all-cause mortality (HR, 1.21 [95% CI, 1.14–1.29]). (Table 2).

Table 1: Association of Cumulative Systolic Blood Pressure Level (Continuous Scale) With Hazards of Cardiovascular Disease (per 130 mm Hg×Year)*

Cum10ySBP quartiles showed significant correlation with CVD incidence, with greater risk as the cumulative SBP increased (Cum10ySBP: HRquartile2: 1.32 [1.14–1.53], HRquartile3: 1.63 [1.41–1.88], and HRquartile4: 2.32 [1.93–2.58] Figure 2A and B). This correlation remained even when index SBP was also included into the model (Cum10ySBP: HRquartile2: 1.14 [0.97–1.32], HRquartile3: 1.21 [1.03–1.42], and HRquartile4: 1.33 [1.10–1.61] Figure 2C). The higher risk correlated with greater cumulative SBP quartiles was also noticed while analysing separately for CHD and CHF (Figure 2B and 2D, respectively).

Figure 2: The association of 10 y cumulative systolic blood pressure quartiles with cardiovascular disease (CVD) and all-cause mortality.*,†,‡

Five forest plots show adjusted hazard ratios (HRs) for any CVD, coronary heart disease (CHD), stroke, congestive heart failure (CHF), and all-cause mortality. ● Model A: unadjusted model. ▲ Model B: adjusted model, not including index systolic blood pressure (SBP). Variables included: 10 years cumulative systolic blood pressure quartiles, age, sex, race, education, body mass index (BMI), smoking status, diabetes, total cholesterol level, and use of hypertensive medications. ■ Model C: Adjusted model, including index SBP. Variables included: model B+index SBP. *Participants were categorized into 4 groups by their cohort-specific Cum10ySBP quartile ranking. The median Cum10ySBP level of quartile 1, quartile 2, quartile 3, and quartile 4 was 990, 1103, 1197, and 1308 for MESA study; 1026, 1118, 1204, and 1328 for ARIC study; 1036, 1119, 1293, and 1305 for CARDIA study; 1081, 1182, 1269, and 1392 for FOS; and 1152, 1261, 1361, and 1525 for FHS, respectively. †For all models, quartile 1 (ie, the quartile with the median Cum10ySBP in the normal range) was defined as the reference group. ‡For CVD outcomes (A–D), Fine & Gray sub distribution method was used to account for the effects of competing risks of death. Cox proportional hazards method was used for the association of Cum10ySBP with all-cause mortality (E).

Thus, it was concluded that a risk factor to CVD and all-cause mortality is the ten-year cumulative exposure to SBP, over and besides current SBP. High level of 10-year cumulative exposure to SBP showed higher CVD risk. Individuals with similar current SBP may be at different long-term risks for CVD because of differences in their increasing exposure to SBP. Thus, cumulative SBP may be used to distinguish individuals based on their risk for CVD.

CVD: Cardiovascular disease; BP: Blood pressure; SBP: Systolic blood pressure; ARIC: Atherosclerosis Risk in Communities; CARDIA: Coronary Artery Risk Development in Young Adults; FHS: Framingham Heart Study; FOS: Framingham Offspring Study; MESA: Multi-Ethnic Study of Atherosclerosis; HR: Hazard ratio; CI: Confidence interval; CHD: Coronary heart disease; CHF: Congestive heart failure