Associations between MRI signs of kidney parenchymal changes and biomarkers of renal dysfunction in resistant hypertension

Abstract

Objective. Resistant hypertension (RHT) is often associated with kidney injury and chronic kidney disease, especially in diabetic patients. Early detection of renal changes contributes to avoiding severe cardiovascular complications, but imaging characteristics of renal dysfunction in RHT remain unclear. The aim of the present study was to determine the relationships between the renal parenchyma volumes and biomarkers reflecting kidney function in a cohort of patients with RHT.Material and Methods. The study comprised 34 patients with RHT meeting the inclusion criteria. Evaluation of renal function was based on the measurements of estimated glomerular filtration rate (eGFR) and serum levels of creatinine and cystatin C. Renal sizes were assessed by MRI based on absolute and normalized parenchymal kidney volumes.Results. Primary MRI-based changes in renal parenchyma in patients with RHT demonstrated altered cortical surface, attenuated cortical thickness, lower renal volumes, and round shape of the kidneys compared with the reference characteristics. Positive correlation of moderate power was found between eGFR value and all parameters characterizing renal parenchyma. The strongest direct correlation was found between eGFR and bsa-TKV (r = 0.6166, p = 0.000); ht-TKV correlated with eGFR (r = 0.4751, p = 0.007) and creatinine (r = –0.4302, p = 0.016). According to linear regression analysis, ht-T-Cortex-V < 32.4 was a key element of MRI-presentation of renal dysfunction in patients with eGFR below 60 mL/min/1.73 m2 (sensitivity of 83.3%, specificity of 60.7%, p = 0.03).Conclusion. MRI study allowed to detect early renal parenchymal changes suggesting the presence of association between renal function and renal parenchymal volume in RHT patients. For the first time, the study revealed MRI-pattern of renal dysfunction in RHT.