Heart rate deceleration and acceleration capacities associated with circadian rhythm of blood pressure in essential hypertension

Abstract Background: This study aimed to investigate the potential association between the circadian rhythm of blood pressure and deceleration capacity (DC)/acceleration capacity (AC) in patients with essential hypertension. Methods: This study included 318 patients with essential hypertension who underwent 24-hour ambulatory blood pressure monitoring. Patients were categorized into three groups based on the percentage of nocturnal systolic blood pressure (SBP) dipping: the dipper, non-dipper and reverse dipper groups. Baseline demographic characteristics, ambulatory blood pressure monitoring (ABPM) parameters, Holter recordings (including DC and AC), and echocardiographic parameters were collected. Results: In this study, the lowest DC values were observed in the reverse dipper group, followed by the non-dipper and dipper groups (6.46±2.06 vs. 6.65±1.95 vs. 8.07±1.79 ms, P <.001). Additionally, the AC gradually decreased (-6.32±2.02 vs. -6.55±1.95 vs. -7.80±1.73 ms, P <.001). There was a significant association between DC (r=0.307, P<.001), AC (r=-0.303, P<.001) and nocturnal SBP decline. Furthermore, DC (β = 0.785, P =.001) was positively associated with nocturnal SBP decline, whereas AC was negatively associated with nocturnal SBP (β = -0.753, P<.002). By multivariate logistic regression analysis, deceleration capacity [OR (95% CI): 0.705 (0.594–0.836), p <.001], and acceleration capacity [OR (95% CI): 1.357 (1.141-1.614), p =.001] were identified as independent risk factors for BP nondipper status. The analysis of ROC curves revealed that the area under the curve for DC/AC in predicting the circadian rhythm of blood pressure was 0.711/0.697, with a sensitivity of 73.4%/65.1% and specificity of 66.7%/71.2%. Conclusions: Abnormal DC and AC density were correlated with a blunted decline in nighttime SBP, suggesting a potential association between the circadian rhythm of blood pressure in essential hypertension patients and autonomic nervous dysfunction.