Association between cardiovascular risk and diastolic blood pressure in older adults with systolic blood pressure less than 130mmHg: a prospective cohort study from 2014 to 2022.

Background: The 2017 American College of Cardiology (ACC)/American Heart Association (AHA) guideline lowered the diagnostic threshold for hypertension to a systolic/diastolic blood pressure (SBP/DBP) of 130/80 mmHg. However, the predictive value of DBP for cardiovascular (CV) risk assessment diminishes with aging. The study aimed to explore whether the new diagnostic threshold for diastolic hypertension is associated with increased risk of CV organ damage and major adverse cardiovascular events (MACEs) in older adults.

Methods: 1181 individuals aged 65 years or older with SBP < 130 mmHg were enrolled a prospective cohort study. They were classified into Low (< 70 mmHg), Optimal (70 to < 80 mmHg), and High (80 to < 90 mmHg) DBP groups. Cardiac, vascular, and renal organ damage were measured at baseline. The endpoint of the study was MACEs.

Results: Among 1181 participants (average age 71.9 years, 44.8% men), 172 MACEs were observed during an average follow-up of 6.4 years. We found no significant differences in CV organ damage or MACEs rates (Log-rank P = 0.73) among three groups. In multivariable Cox regression, compared to the Optimal DBP group, no significant increase in CV risk was observed in the Low DBP group (hazard ratio [HR] 1.02, [95% CI 0.68-1.52], P = 0.93) or the High DBP group (HR 1.04, [95% CI 0.72-1.49], P = 0.85). Propensity score matching showed consistent results.

Conclusion: In older adults with SBP < 130 mmHg, DBP values 80-89 mmHg were not associated with higher risk of CV organ damage, events or mortality.