Assessment of Renal Function and Electrolyte Balance in Patients with Cardiovascular Disease at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia

Introduction: Chronic kidney disease (CKD) and electrolyte imbalance are known in patients with cardiovascular disease (CVD), and cause extra morbidity and mortality. However, there is no published study on renal disease and electrolyte imbalance among cardiovascular (CV) patients in Ethiopia.

Objective: To assess the renal function and electrolyte balance in patients with CVD at Tikur Anbessa Specialized Hospital (TASH).

Methods: A cross-sectional study was conducted from September to November 2017, on 163 CV patients attending the emergency department (ED) of TASH.

Results: CKD, defined as estimated Glomerular Filtration Rate (eGFR) < 60 ml/min/1.73 m2, was found in 39 (23.9%) and 35 (21.5%) participants according to the Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease- Epidemiological Collaboration (CKD-EPI) equations, respectively. CKD was significantly associated with hypertension (p= 0.019), systolic blood pressure (SBP), (p = 0.009), serum creatinine (SCr), (p = 0.001) and blood urea nitrogen (BUN), (p = 0.001) when defined by CKD-EPI equation and with SBP (p = 0.023), SCr (p = 0.001) and BUN (p = 0.001) when defined by MDRD equation. In serum electrolyte disorders, 80 (49.1%) patients had serum Cl- imbalance, 59 (36.2%) had serum Na+ imbalance and 37 (22.7%) had serum K+ imbalance. Loop diuretic was significantly associated with hypochloremia (p = 0.001) while potassium sparing diuretic was associated with the presence of hyponatremia (p = 0.036) and hypochloremia (p = 0.003).

Conclusion: CKD was present in 21.5– 23.9% of CV patients, but it is usually undiagnosed using SCr alone. Therefore, GFR should be considered as an estimate of renal insufficiency regardless of SCr levels. In addition, electrolyte disorders were also higher among CV patients.