Objective:

To evaluate the incidence of acute kidney injury (AKI) in hospitalized patients with exertional rhabdomyolysis (ERM) and investigate the association between serum CK and AKI, providing insights for the admission and discharge management of patients with elevated CK.

Background:

While elevated serum creatine kinase (CK) has been suggested as a risk factor for AKI in patients with ERM, the actual incidence of AKI and contributing cofactors remain unclear. This study examines the role of CK levels and other potential risk factors in the development of AKI among hospitalized ERM patients.

Design/Methods:

This retrospective cohort study was conducted in a diverse population of patients aged 18 years and older with ERM, hospitalized between 2009 and 2019 across Kaiser Permanente Northern California. Patients were identified through electronic screening for rhabdomyolysis admissions, followed by a medical record review to confirm eligibility. AKI diagnosis was based on KDIGO criteria.

Results:

Among 200 confirmed ERM patients (mean age 30.5 years, 72.5% male), 17 (8.5%) developed AKI, none developed CKD, 1 (0.5%) developed compartment syndrome, and there were no fatalities. There was no significant association between serum CK levels and AKI risk. However, AKI was significantly more likely in patients with preadmission NSAID use (64.7% vs. 21.9%, P < .001) or dehydration (52.9% vs. 4.9%, P < .001). Eliminating these factors could reduce the risk of AKI by 92.6% (95% CI, 85.7%-96.1%). Additionally, none of the ERM patients without AKI at admission developed AKI later; all AKI cases were identified upon admission.

Conclusions:

Elevated CK alone is not a reliable predictor of AKI in ERM patients. Preadmission NSAID use and dehydration are significantly associated with increased AKI risk. This study provides important implications for hospital admission, discharge planning, and patient counseling.