Brain Natriuretic Peptide Levels in Hypertensive Heart Failure Patients with and without Diabetes Mellitus: A Cross-sectional Study

Abstract

Introduction: Heart Failure (HF) is a major disorder causing mortality and morbidity in the elderly population. Brain Natriuretic Peptide (BNP) is considered as the gold standard biomarker for diagnosis of HF. Aim: To find the association of plasma BNP levels with heart failure in hypertensive patients with and without diabetes mellitus. Materials and Methods: This cross-sectional study consisted of 35 hypertensive heart failure patients who attended the Outpatient General Medicine Department at Sri Ramachandra Medical College and Research Institute, Chennai, Tamil Nadu, India, between March 2020 to December 2020. The patients who belonged to class IV heart failure of the New York heart association were included. Total 35 HF patients were divided into two groups. Group 1 included 10 patients with hypertensive heart failure without diabetes mellitus. Group 2 included 25 patients with hypertensive heart failure with diabetes mellitus. Parameters such as Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP), waist to hip ratio, Body Mass Index (BMI), Ejection Fraction (EF), transmitral filling velocities (E/A ratio), Left Ventricular Posterior Wall Thickness (LVPW), Left Ventricular Internal Dimension in diastole (LVIDd) and BNP level, random plasma glucose and HbA1c % were assessed in all the patients. Student’s t-test and Mann-Whitney U test were used to statistically analyze the data and p-value ≤ 0.05 was considered statistically significant. Results: Mean age of patients were 65.80±12.72 years in group 1 and 66.56±11.72 years in group 2. All patients in group 1 and most of the patients in group 2 (15,42%) were males. All the patients were in the obese category (BMI>27 kg/m2 ). Serum BNP level was 1365 (243-3680) ng/L in group 1 and 691 (44.7-4261) ng/L in group 2, but this difference was not statistically significant (p-value=0.23). Echocardiography showed significant differences in left ventricular internal dimension in diastole, left ventricular posterior wall thickness and E/A ratio-integrated between hypertensives and hypertensives with diabetes mellitus. Serum BNP had a significant positive correlation with systolic blood pressure (r=0.33, p-value=0.05). There were highly significant differences in random plasma glucose and glycated haemoglobin between the groups. Conclusion: Plasma BNP levels were associated with systolic blood pressure in heart failure patients with hypertension. The significance of association is the same in hypertensives with diabetes mellitus. Thus, BNP as a biomarker plays a major role in the prediction of heart failure. But BNP could not differentiate whether the heart failure was due to hypertension alone or due to associated metabolic conditions.