Associations of circadian blood pressure rhythm with autonomic nervous system and myocardial energy expenditure level in patients with primary hypertension / 南方医科大学学报

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the relationship among circadian blood pressure rhythm, autonomic nervous system and myocardial energy expenditure (MEE) level in patients with primary hypertension.</p><p><b>METHODS</b>A total of 102 hypertensive and 45 normotensive subjects were recruited. According to blood pressure reduction rate at night, the hypertensive patients were divided into non-dipper group (NDH group, n=54) with a reduction rate of <10% and dipper group (DH group, n=48) with a reduction rate of ≥10%. The circadian blood pressure rhythm and heart rate variability were measured with ambulatory blood pressure monitoring and 24-hour electrocardiograph monitoring, respectively, and MEE was measured by Doppler echocardiography to analyze their correlations.</p><p><b>RESULTS</b>SDNN, SDANN, SDNNindex, RMSSD, PNN50, and HF were significantly lower in the hypertensive patients than in the control group (P<0.05); these parameters, except for PNN50, were all significantly lower in NDH group than in DH group (P<0.05). The hypertensive patients had significantly higher MEE than the control group (P<0.05), and MEE was significantly higher in NDH group than in DH group (P<0.05). Bivariate correlation analysis showed significant correlations of MEE with SDANN in the hypertensive patients (P<0.01).</p><p><b>CONCLUSION</b>Patients with primary hypertension, especially those in NDH group, have impaired autonomic nervous system function. The hypertensive patients in NDH group show a more prominent increase in MEE in relation to sympathetic activation, suggesting the importance of restoring circadian blood pressure rhythm in the treatment of hypertension.</p>