Abstract 2454: Nondipping of the Sleeping Pulse Rate in Nondipper Hypertensives is a Synergistic Risk of Stroke
Background: Nondipper refers to a subgroup of patients showing abnormal diurnal blood pressure (BP) variation which is associated with cardiovascular events. However, there have been few reports on the relationship between variation in the diurnal pulse rate (PR) in relation to a nondipper BP pattern and stroke.
Methods: Ambulatory BP monitoring (ABPM) was conducted at the baseline in 811 older Japanese hypertensives (clinical BP ≥140/90 mmHg, age ≥ 50 years old) enrolled in the Jichi Medical School ABPM Study, wave 1. They were followed-up for an average of 41 months, and the incidence of subsequent stroke was evaluated. Nondipping of the sleep PR was defined as: (awake PR - sleep PR)/awake PR < 0.1. The incidence of stroke was analyzed by Kaplan-Mayer method and Cox proportional hazard modeling.
Results: The patients’ age was 72.3 ± 9.8 years (311 men and 500 women). The nondipper patients had a higher risk of stroke than the dippers (9.9% vs. 5.7%, p=0.039). Patients were classified into 4 subgroups: dippers with dipping of the sleep PR (n=471), dippers with nondipping of the sleep PR (n=37), nondippers with dipping of the sleep PR (n=250) and nondippers with nondipping of the sleep PR (n=53). The nondippers with nondipping of the sleep PR had a higher risk of stroke than the other three subgroups (17.0% vs. 6.6%, p=0.005). On Cox proportional hazards modeling, which included age, gender, ambulatory systolic BP, and PR, nondipping of the sleep PR in nondippers led to a significant increase in the incidence of stroke (Hazard ratio: 2.10; 95% confidence interval:1.03– 4.29, p=0.041).
Conclusion: A blunted PR dip might synergistically predict a stroke in hypertensives with a nondipping BP status.