NOCTURNAL NON-DIPPING STATUS AND LEFT VENTRICULAR HYPERTROPHY IN HYPERTENSIVE PATIENTS

Abstract

Objective: Ambulatory Blood Pressure Monitoring (ABPM) is used to assess the dipping status in hypertensive patients according to the nocturnal blood pressure (NBP) decline: extreme dippers, dippers, non-dippers and inverted dippers. Increased NBP is currently regarded as a risk factor for cardiovascular (CV) events and hypertension-mediated organ damage (HMOD). One of the most common HMOD include left ventricular (LV) remodelling as chronic BP elevation may progressively increase LV thickness. The aim of this study is to determine if there is a higher prevalence of LVH in echocardiographic (ECHO) parameters in patients with increased NBP. Design and method: Prospective observational study. Inclusion criteria: subjects with treated hypertension undergoing ABPM performed in our Primary Health Care Unit and with ECHO in the last 3 years. Fisher's exact test was used whenever appropriate to assess independence and statistical significance of reported factors. Logistic regression analysis was performed to assess the effects and its statistical significance between established parameters. Statistical differences were indicated as p < 0.05 and p < 0.01. Statistical analysis was performed using R version 4.0.3. Results: For this study, 67 patients were screened, from which 44 were male and 23 females, average age of 55 years old. We obtained a distinct distribution of dipper and non-dipper profiles in a LVH dependent manner. The non-dipper presented higher significant effect with LVH (p < 0.01) and the results obtained from the fisher test showcase a statistically significant relation between non-dippers and LVH (annex 1) Conclusions: The limitations of this study included the small sample size and the usage of a questionable diagnose of dipping status in a 24 h period since it is often highly variable. Based on the results, there seems to be an impact of NBP on LV structure since there is a statistically significant relation between non-dipper status and LVH. Hypertensive patients should be submitted to ECHO and other forms of HMOD screening, especially non-dippers, considering their increased CV risk, in order to improve CV risk stratification therapeutic strategies.