Myoglobin Status in Stable Patients with Chronic Kidney Disease

Abstract

Aim: To measure serum myoglobin concentration in stable patients with chronic kidney disease (CKD) who had not commenced hemodialysis and determine its relationship with cardiovascular risk factors. Study Design: Cross-sectional study. Place and Duration of Study: Renal Unit, Department of Internal Medicine, University of Port Harcourt Teaching Hospital, Rivers State, Nigeria from January 2014 to December 2015. Methodology: Blood pressure, serum myoglobin, HDL-cholesterol, total cholesterol, triglyceride, fasting plasma glucose, urine and serum albumin, urine and serum creatinine concentrations were measured in 83 diagnosed chronic kidney disease patients attending the renal clinic and 83 age- and sex-matched healthy control subjects. Body mass index (BMI), estimated glomerular filtration rate (eGFR), urinary albumin-creatinine ratio (UACR) and LDL-cholesterol were calculated.  Results: CKD patients had higher myoglobin, higher blood pressure, higher serum creatinine, higher triglyceride, higher UACR, lower serum albumin, lower HDL and lower eGFR compared to controls. Nineteen (22.9%) patients versus zero (0%) controls had elevated myoglobin. Among patients, myoglobin was associated positively with serum creatinine and UACR but inversely with eGFR. Apart from obesity, high myoglobin levels were not significantly associated with cardiovascular risk factors. Conclusion: Serum myoglobin elevation in CKD patients was associated with high UACR and low eGFR, which are indicative of progressive decline of renal function. Myoglobin levels are influenced by impaired renal status and not primarily related to cardiovascular risk factors in stable patients with CKD. Thus, it may not be useful as a biomarker of myocardial injury in CKD patients.