Risk of Acute Kidney Injury Following Gadolinium-based Contrast Agent-enhanced MRI: Propensity-matched 7-year Cohort Study.

Objectives: The kidney plays a vital role in eliminating gadolinium-based contrast agents (GBCAs), and renal function may contribute to various GBCA-associated adverse drug reactions (ADRs), particularly acute kidney injury (AKI). The objective of the study is to investigate whether GBCA administration elevates AKI risk and explore the correlation between renal function and the incidence of GBCA-associated acute ADRs.

Materials and methods: Adult patients who underwent MRI examinations between January 2015 and June 2021 at the inpatient department of a single tertiary general hospital were retrospectively examined. Baseline estimated glomerular filtration rate (eGFR) before MRI examination, serum creatinine levels of the nearest timepoint before and after MRI examinations, and symptoms of GBCA-associated acute ADRs were retrospectively reviewed. AKI was diagnosed based on the Kidney Disease: Improving Global Outcomes guideline. Propensity score matching and inverse probability of treatment weighting were used to adjust for selection bias. The rates of GBCA-associated acute ADRs and AKI were compared using generalized estimating equation (GEE) for total data and randomly sampled one patient-one examination data.

Results: This study included 35,197 MRI examinations with available serum creatinine levels, and AKI was diagnosed in 569 cases (1.62%; 95% CI: 1.48%-1.75%). Logistic regression with GEE after propensity score matching revealed a significantly lower AKI incidence in examinations with GBCA enhancement (OR, 0.59; 95% CI: 0.46-0.77; P < 0.001); this finding was consistent across patient groups with both eGFR of >60 mL/min/1.73 m2 (OR, 0.53; 95% CI: 0.34-0.84; P = 0.007) and eGFR between 30 and 60 mL/min/1.73 m2 (OR, 0.49; 95% CI: 0.32-0.74; P < 0.001). The rates of GBCA-associated acute allergic-like reactions (adjusted OR, 1.01; 95% CI: 1.00-1.02; P = 0.125) and physiological reactions (adjusted OR, 1.00; 95% CI: 0.98-1.02; P = 0.997) showed no significant association with baseline eGFRs.

Conclusions: In this large retrospective study, the administration of GBCAs was not associated with higher rates of AKI, which remained consistent across varying levels of baseline renal function. Furthermore, no significant increase in GBCA-associated acute ADRs was observed in patients with impaired renal function. These findings suggest that GBCA administration is generally well-tolerated across a wide spectrum of renal function, without increasing the risk of AKI or GBCA-associated acute ADRs.