Postoperative acute kidney injury is associated with persistent renal dysfunction: a multicentre propensity-matched...

Area of Science:

• Nephrology
• Surgical Outcomes
• Critical Care Medicine

Background:

• The long-term renal function consequences of postoperative acute kidney injury (pAKI) remain incompletely understood.
• Establishing the risk of persistent renal function reduction after pAKI is crucial for patient management.

Purpose of the Study:

• To determine if patients experiencing pAKI exhibit a greater decline in long-term renal function compared to those without pAKI.
• To quantify the association between pAKI and sustained reduction in glomerular filtration rate (GFR).

Main Methods:

• A multicentre retrospective study analyzed data from 95,213 adult patients across three tertiary care hospitals.
• Patients were propensity-score matched and stratified based on the occurrence of pAKI, defined by the Acute Kidney Injury Network classification.
• The primary outcome assessed was a 40% decline in follow-up GFR from baseline, evaluated over 0–36 months post-discharge using piecewise Cox models.

Main Results:

• The incidence of pAKI ranged from 9.9% to 13.7% across the study population.
• pAKI was significantly associated with an increased hazard of a 40% GFR decline.
• Hazard ratios for a 40% GFR decline ranged from 13.35 (0-6 months) to 4.32 (24-36 months), all with P<0.001.

Conclusions:

• Postoperative acute kidney injury is linked to a substantially elevated risk of a 40% decline in GFR.
• This increased hazard persists for up to 36 months following surgical procedures.
• Findings highlight the critical importance of monitoring renal function in patients who experience pAKI.