Abstract P108: Correlations of attended and unattended office blood pressure measurements with Left Ventricular Mass in untreated hypertensives.

Abstract

Introduction: Unattended (UA) office blood pressure (BP) measurements have been proposed as better substitutes for attended (AT) BP readings for the diagnosis and monitoring of patients with hypertension (HTN). A superior correlation of UA over AT BP measurements with Left Ventricular Hypertrophy (LVH), an early marker of hypertensive organ damage has not been conclusively demonstrated. We hypothesized that in a group with untreated HTN, UA BP would correlate more strongly with left ventricular hypertrophy than AT BP. Methods: Newly diagnosed untreated patients with HTN presenting newly to an outpatient clinic in Nigeria were consented as part of a larger study. Three sets of AT and UA seated BP readings were carried out using a validated device followed by same-day echocardiographic assessment of their Left Ventricular Mass Indexed to Body surface area (LVMI). Pearson’s coefficient (r) was determined and a 2-tailed significance was defined by a two-tailed P value (P) less than 0.05. Coefficients were compared using Fisher r to z transformation. Results: A total of 49 participants (female=25) were recruited with a mean age of 46.2 +/- 9 years. The mean of the AT BP in the cohort (mAT) was 157.1 +/- 13.5mmHg, while the mean of the UA BP was 151.9 +/- 15.7 with no significant difference in both (P=0.085). The mean LVMI of the cohort was 102.3 +/- 28.7 mg/m2. Both the mAT BP (r= 0.304, P= 0.034) and the mUA BP (r=0.354, P=0.013) positively correlated with LVMI, with no significant difference in the strength of both correlations with r to z transformation (z=0.27, P=0.394 ). Conclusion: In a small cohort of newly diagnosed Nigerian hypertensives, both attended and unattended systolic office blood pressure readings correlated positively with left ventricular mass indexed to body surface area, with no significant difference in the strength of their correlation. Having failed to demonstrate a superior correlation of unattended blood pressure readings with LVH, our findings support the continued use of attended office blood pressure readings for clinical monitoring in busy time-constrained office settings where unattended office blood pressure monitoring may not be feasible. Larger studies are however required to confirm these findings.