Relationship of Blood Pressure Variability and Heart Rate with Plasma hsCRP in Patients with Recently Diagnosed Hypertension

Kim, Dongmin; Lim, Seong Hoon; Lee, Myung Yong

Abstract

BACKGROUND/AIMS
Blood pressure (BP) variability and heart rate (HR) are associated with target organ damage and cardiovascular complications; however, the exact mechanisms are uncertain. In this study, we examined the association of an inflammatory marker with BP variability and HR.
METHODS
A total of 151 patients diagnosed recently with hypertension were subjected to 24-h ambulatory BP monitoring. BP variability was assessed as the standard deviation of the BP recordings. The average HR and HR variability were calculated from concomitantly recorded HR values. Plasma high-sensitivity C-reactive protein (hsCRP) was used as a marker of inflammation.
RESULTS
The mean age of the study population was 44 +/- 11.3 years, and 74.2% of the patients were male. The plasma hsCRP level was higher in male patients (0.131 +/- 0.014 vs. 0.06 +/- 0.023, p = 0.001) and patients with a history of smoking (0.136 +/- 0.017 vs. 0.101 +/- 0.017, p = 0.003). A correlation analysis showed that the variability in diastolic BP during 24-h monitoring was associated with hsCRP (p = 0.002, r = 0.258). The 24-h (p = 0.004, r = 0.236), daytime (p = 0.003, r = 0.239), and nighttime (p = 0.020, r = 0.190) average HRs were related to the hsCRP level. The 24-h HR variability (p = 0.025, r = 0.182) was also associated with hsCRP. After adjusting for the effect of related variables, the 24-h diastolic BP variability (beta = 0.286, p = 0.011) and daytime average HR (beta = 0.169, p = 0.049) were positively related to hsCRP.
CONCLUSIONS
Plasma hsCRP is related to diastolic BP variability in recently diagnosed hypertensive patients. Moreover, HR measured with BP is associated with hsCRP. These findings suggest that inflammation mediates adverse cardiovascular outcomes of BP variability and an elevated HR.