Systemic vascular resistance higher in people with family history of hypertension

Individuals with a family history of hypertension show increased central and peripheral blood pressure (BP) potentially due to higher systemic vascular resistance (SVR), according to a study. On the other hand, large artery stiffness is not elevated.

The authors recorded the haemodynamics of participants with (n=437) and without (n=274) a family history of hypertension using continuous tonometric pulse wave analysis and whole-body impedance cardiography during passive head-up tilt.

Participants with a family history of hypertension showed a higher percentage of antihypertensive medication users (15.6 percent vs 8 percent; p=0.003) and higher office BP (143/91 vs 180/87 mm Hg; p<0.05) than those without hypertensive first-degree relatives. The two cohorts had similar mean age (48.2 vs 48.1 years) and proportion of men (51.9 percent vs 55.1 percent).

During head-up tilt, participants with a family history of hypertension were consistent for having 5/4-mm Hg higher radial and aortic BP (p<0.001 for all comparisons), a shorter aortic reflection time (‒2.4 ms; p=0.017), and a higher SVR index (180 dyn s/cm5 m2; p<0.001) than those without.

No between-group differences were noted in central forward wave amplitude, pulse pressure, augmentation pressure, augmentation index, heart rate, cardiac output, and pulse wave velocity.

All haemodynamic variables significantly changed in response to head-up tilt, with no between-group differences.

“These findings highlight the role of SVR in the pathogenesis of primary hypertension,” the authors said.