Abstract 4146586: NT-proBNP: A Potential Diagnostic Tool for Left Ventricular Hypertrophy in Patients with Chronic Kidney Disease in a Tertiary Hospital In Sub-Saharan Africa

Introduction: Left ventricular hypertrophy (LVH) is a prognostic marker for cardiovascular events in patients with chronic kidney disease (CKD). Detecting LVH is a desirable goal in the management of CKD patients, but ECG has a limited performance and echocardiography is not always available nor is it cost-effective. NT-proBNP is a biomarker released in the setting of LVH, easily measurable but has been shown to also increase with declining kidney function. We aimed to assess the diagnostic value of NT-proBNP for LVH in CKD patients. Research Question: What is the diagnostic utility of NT-proBNP for left ventricular hypertrophy in CKD patients without kidney replacement therapy at the Douala General Hospital, Cameroon, Africa? Material and Methods: We conducted a cross-sectional analytical study at the Douala General Hospital, Cameroon between January and May 2022; 57 patients with CKD stage 2-5 without kidney replacement therapy were matched to 52 healthy control patients by age and gender. Both groups underwent NT-proBNP measurement using enzyme-linked fluorescence with Vidas, Biomerieux® equipment and a transthoracic echocardiography. Left ventricular mass index (LVMI) was assessed in accordance with American Society of Echocardiography guidelines. The correlation between LVMI and NT-proBNP was assessed, the specificity, sensitivity, negative and positive predictive values were calculated. Results: Overall we included 109 patients in our study. Median (IQR) age of CKD patients was 64 (51-70) years and 41 (72%) of CKD patients were male. In CKD patients, median NT-proBNP of 222 pg/ml (118 – 737) was significantly higher than in non-CKD patients, 29 pg/ml (19.5 – 53), p<0.001. Median NT-proBNP increased with CKD stage (p=0.006). In CKD patients left ventricular mass index (LVMI) and LVH frequency increased across NT-proBNP quartiles, p=0.015 and 0.031 respectively. LVMI correlated positively with NT-proBNP (r=0.36, p=0.006) in CKD patients. At a cut-off of 483.5 pg/ml, NT-proBNP area under the curve was 0.75 (0.59 – 0.91) 95 CI, with a specificity of 83%, sensitivity of 75%, positive predictive value of 63% and negative predictive value of 90% for LVH. Conclusion: NT-proBNP is moderately sensitive and highly specific for diagnosing LVH in patients with CKD. NT-proBNP may be used for LVH diagnosis, further studies are warranted to confirm its contribution for cardiovascular risk stratification of patients with CKD.