The Relationships Between Nocturnal Reducing Rate Of Systolic Pressure And Heart And Heart Rate Variability In Subjects With Essential Hypertension

ObjectiveTo investigate the relationships between nocturnal systolic pressure reducing rate(NSPRR) and heart and heart rate variability in subjects with essential hypertension and analysis the contributory factors to the NSPRR. MethodEssential hypertension patients hospitalized in the second hospital affiliated to Zhengzhou University from September 2013 to January 2016 and performed 24-hour ambulatory blood pressure monitoring(ABPM) and Holter monitoring were analyzed through case reviews. Patients were divided into dipping group(10%≤NSPRR≤ 20%), non-dipping group(0 < NSPRR < 10%) and reverse dipping group(NSPRR≤0) according to NSPRR showed in the ABPM results. Age, sex ratio,24 h mean systolic pressure(MSP), 24 h mean diastolic pressure(MDP), diurnal mean systolic pressure(DMSP),diurnal mean diastolic pressure(DMDP),nocturnal mean systolic pressure(NMSP),nocturnal mean diastolic pressure(NMDP), usage of hypotensive drugs, biochemical markers, 24 h mean heart rate(MHR),mean diurnal heart rate(MDHR), mean nocturnal heart rate(MNHR) and the parameters of time domain heart rate variability including standard deviation of all normal to normal intervals(SDNN), standard deviation of the 5-minute mean R-R intervals(SDANN) and root mean square of the successive differences(RMSSD) were compared among three groups. Relationships between NSPRR and MHR,MDHR, MNHR, SDNN, SDANN, RMSSD were analyzed by Pearson correlation. Multiple liner regression was used to analyze the contributory factors to the NSPRR. ResultA total of 211 patients,124 males and 87 females, aging from 40 to 75 years old, were analyzed with 67 patients divided into dipping group,93 into non-dipping group,51 into reverse dipping group.Age, sex ratio, usage of hypotensive drugs showed no significant difference among three groups. HDL-C in reverse dipping group was significantly lower than that in another two.Compared to dipping group, CAD ratio, NMSP, MHR,MDHR, MNHR in non-dipping and reverse dipping group was significantly higher [11.9%,20.4% VS31.4%,(119.8±10.1),(132.4±12.2)vs(113.5±9.3)mmHg,(70.7±6.6),(74.2±9.8)vs(66.8±5.8)beats/min,(74.6±7.5),(78.8±9.8)vs(70.6±6.5)beats/min,(64.1±6.4),(68.3±7.6)vs(59.6±4.9)beats/min, all P<0.01], while SDNN、SDANN、RMSSD were significantly lower [(116.0±17.9),(105.7±13.7)vs(136.8±20.3)ms,(100.6±19.3),(90.9±14.1)vs(117.8±21.2)ms,(34.8±11.1),(26.1±8.5)vs(41.4±13.9)ms, all P<0.01].Compared to non-dipping group, CAD ratio, NMSP, MHR,MDHR, MNHR in reverse dipping group were significantly higher,while SDNN、SDANN、RMSSD were significantly lower.NSPRR was negatively correlated to MHR,MDHR and MNHR(r=-0.317,-0.326,-0.410, all P<0.05), while positively correlated to SDNN,SDANN and RMSSD(r=0.504,0.430,0.410,all P<0.05). Multiple liner regression analysis showed that DMSP,NMSP,MHR,SDNN and CHD were influential factors of NSPRR(B=-0.744,0.697,-0.025,0.010,-0.387, both P<0.05). Conclusion1.Decreased nocturnal reducing rate of systolic pressure was related to increased heart rate and decreased HRV in subjects with essential hypertension.2.DMSP,NMSP,MHR,SDNN and CHD were influential factors of NSPRR,whlie the controled blood pressure was not.3.Patients with reverse dipping blood pressure had lower level HDL-C and higher incidence of CAD.