Study of home-monitored night blood pressure and its correlation with left ventricular hypertrophy in treatment-naive hypertensive patients

Pai AU, Chakrapani  M, Bhaskaran U, Kamath P
Correspondence: Dr Chakrapani M, chakrapani.m@manipal.edu

ABSTRACT
Introduction 24-hour ambulatory blood pressure (BP) monitoring is a well-validated tool that can reveal the patient’s nocturnal dipping pattern. However, to the best of our knowledge, the role of home BP monitoring in identifying nocturnal dipping has not been studied.
Methods We evaluated the nocturnal BP of 30 treatment-naive subjects using a home BP monitoring device. BP measurements were taken once during the daytime and once at night (three hours after sleep) by a blinded observer. Readings were correlated with left ventricular mass index.
Results Night BP measurements were significantly lower in subjects without left ventricular hypertrophy (LVH) as compared to those with LVH, while the daytime readings were not significantly different between the two. The mean dips in nocturnal systolic and diastolic BP were 1.92% ± 6.89% and −0.55% ± 14.31%, respectively, in subjects with LVH. The corresponding values were 12.96% ± 6.16% and 11.36% ± 11.90% in those without LVH.  The correlation between left ventricular mass index and night BP readings was statistically significant (systolic r = 0.66, p < 0.001; diastolic r = 0.496, p < 0.005).  
Conclusion  Nocturnal BP measurement using a home BP monitoring device may be a reliable and cost-effective  method for detecting early signs of end-organ involvement such as LVH in hypertensives, especially in a resource-limited setting.

Keywords: ambulatory blood pressure monitoring, home blood pressure monitoring, left ventricular hypertrophy
Singapore Med J 2012; 53(2): 95–98