The following is a summary of “Association of Mean Arterial Pressure Variability With Kidney Function in Living Kidney Donors,” published in the November 2023 issue of Cardiology by Tantisattamo et al.
Living kidney donors (LKDs) face potential long-term risks, but the impact of mean arterial pressure (MAP) variability on their kidney function remains unclear. Researchers conducted a retrospective study to assess whether MAP variability post-donation impacts kidney function in living donors.
They used OPTN/SRTR, which included adult LKD undergoing donation (6/1972 and 9/2022). MAP variability was assessed through the average real variability of MAP (ARV-MAP), defined as the average absolute difference in consecutive MAP at 6, 12, and 24 months post-donation. The risk of a ≥35% decrease in post-donation estimated Glomerular Filtration Rate (eGFR) from pre-donation eGFR among quartiles (Q) for ARV-MAP was examined by multivariable Cox regression.
The results showed 136,984 LKD, the mean±SD age of 42±12 years, with 61% female. Mean pre-donation Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP), and MAP were 122±13, 74±9, and 90±10 mmHg, respectively. Mean post-donation BP at 6, 12, and 24 months was 120±13 / 75±9, 120±13 / 75±9, and 120±12 / 75±9 mmHg, respectively, and corresponding mean post-donation MAP was 89.7±9.1, 89.8±9.0, and 90.2±9.0, respectively. The median (IQR) ARV-MAP was 6 (3, 10) mmHg. Mean pre-donation eGFR was 102.1±29.1 ml/min/1.73 m2, and eGFR at 6-, 12-, and 24-months post-donation were 60.7±42.6, 62.4±43.9, and 64.4±44.9 ml/min/1.73 m2, respectively. The incidence rate of the event was 8.21 per 100 person-months. Compared to Q1 of the ARV-MAP, only Q3 had a 3.8% higher risk for declined eGFR (HR Q3 (95% CI) 1.04 (1.00, 1.08)). After adjusting for various factors, Q2, Q3, and Q4 had a 6.3%, 8.3%, and 6.9% significantly greater risk of the event, respectively (HR Q2 1.06 (1.00, 1.12); HR Q3 1.08 (1.02, 1.14); HR Q4 1.07 (1.01, 1.13)). There was no effect modification of the covariates for the ARV-PP – post-donation eGFR association.
They concluded that LKD with glomerular hyperfiltration saw a higher risk of kidney decline with ARV-MAP.
Source: ahajournals.org/doi/10.1161/circ.148.suppl_1.16656
