CORRELATION OF ESTIMATED GLOMERULAR FILTRATION RATE WITH LEFT VENTRICULAR DIASTOLIC FUNCTION IN CHRONIC KIDNEY DISEASE PATIENTS NOT ON DIALYSIS

Introduction:

Cardiovascular disease(CVD) is the main cause of death for patients with chronic kidney disease. Estimated glomerular filtration rate (eGFR) is an independent predictor of cardiovascular events. GFR is the best overall index of kidney function. Diastolic dysfunction is among newly identified risk factors for CVD in patients with later stages of CKD. The gold standard for assessment of diastolic function has been the invasively obtained pressure-volume loop in which diastolic function is assessed as instantaneous relationship between pressure and volume. But since it is invasive, we prefer Doppler echocardiography, which is best suited to assess diastolic function by analyzing flow across mitral valve during diastole. Early identification of CKD patients with LV diastolic dysfunction might help in developing treatment strategies and in choosing patients most likely to benefit from these strategies.

Methods:

STUDY DESIGN: Cross sectional study.

STUDY POPULATION: Diagnosed cases of CKD not on dialysis (with eGFR less than 60 ml/min for more than 3 months).

STUDY SETTING: The patients are from Nephrology department of Ernakulam Medical Centre, Kochi, Kerala – 682028 which is a tertiary care hospital.

STUDY PERIOD: September 2022 to January 2024.

SAMPLE SIZE: Assuming an alpha error of 5%, power of 80%, mean E/A ratio to be 0.8 and standard deviation of E/A ratio to be 0.2, the minimum sample size was calculated to be 80.

SAMPLING METHOD: Purposive sampling.

INCLUSION CRITERIA

CKD patients in the age group of 20 to 65 years who were not on dialysis. Subjects were divided into 5 groups based on eGFR: Group 1: 60-89, Group 2: 45-59, Group 3: 30-44, Group 4: 15-29, Group 5: <15 (ml/min/1.73m2).

EXCLUSION CRITERIA: Patients with systolic dysfunction (ejection fraction less than 50%), atrial fibrillation, acute coronary syndrome, cardiomyopathy and valvular disorders were excluded from the study.

STUDY TOOLS

1. MDRD (modification of diet in renal disease) formula for estimation of glomerular filtration rate.

2. Standard echocardiographic parameters to assess left ventricular diastolic function.

Results:

Conclusions:

Left ventricular diastolic (LVD) function worsened in parallel with worsening of eGFR. CKD patients with eGFR < 30 ml/min/1.73 m2 had a higher incidence of LVD dysfunction. Grade III diastolic dysfunction was observed in 56% of Group 4 and 5 patients. However there was no statistically significant association between LVD function and eGFR in the study groups. There was statistically significant association between LVD function and female gender. Hence, females are more likely to develop diastolic dysfunction at equivalent stages of CKD. LVH and age had no statistical association with LVD function as in the previous studies. Standard echocardiographic parameters can be used to detect subtle changes of LVD dysfunction in CKD patients when the systolic function is preserved. We conclude that the patients with CKD develop a progressive reduction in diastolic function and it occurs before the onset of a clinical heart failure. Hence we recommend screening of all asymptomatic CKD patients and suggest routine evaluation of diastolic function by echocardiography and serial follow up to look for worsening of diastolic function. Detection of significant diastolic dysfunction can be early markers of myocardial disease and increased risk in advanced CKD.

I have no potential conflict of interest to disclose.

I did not use generative AI and AI-assisted technologies in the writing process.