The Association Between Morning Blood Pressure Surge and Cardiovascular Disease in Normotensive Type 2 Diabetic Patients: Observational Analytical Study in the Form of a Cross-Sectional Study

Morning increase and nighttime decrease in blood pressure (BP) have been associated with cardiovascular (CV) morbidity and mortality in general and diabetic subjects. We aimed to study the association between morning blood pressure surge (MBPS) and left ventricular hypertrophy (LVH) in normotensive type 2 diabetes mellitus (T2DM) patients. This comparative cross-sectional study included 90 normotensive T2DM patients divided according to the presence of diastolic function into two groups. Normotensive T2DM patients were subjected to ambulatory blood pressure monitoring (ABPM) to detect the MBPS and echocardiography to assess left ventricular mass index (LVMI) and diastolic function. Data were analyzed using SPSS and stepwise multiple regression and binary logistic regression analysis was performed to detect the associated independent variables for increase in LVMI. Finally, a receiver operating characteristic (ROC) curve was performed to assess a cut-off value for MBPS. A total of 31% of patients had diastolic dysfunction (DD). There was a strong positive correlation between LVMI and MBPS (r = 0.609, p-value < 0.001). Stepwise multiple regression analysis showed that MBPS was the first independent predictor associated with increased LVMI. Binary logistic regression analysis for the status of diastolic function showed an odds ratio (OR) of 1.26 and 1.11 at 95% confidence interval (CI) for MBPS and age respectively. ROC curve for prediction of DD based on the degree of MBPS showed a fair area under curve and a cut-off value of 25.5 mmHg with 85.7% sensitivity and 61.3% specificity. Higher levels of MBPS are associated with increased LVMI and DD in normotensive T2DM patients. This has potential implication as it might be a significant predictor for discovery of subclinical hypertension in early stages of diabetes mellitus and can help in the prevention of heart failure development.