AKI Common in Patients Treated for Cancer

New Orleans—There is an increased risk for acute kidney (AKI) among patients being treated for cancer; however, there have been limited studies on the incidence of AKI and risk factors in the current treatment era.

Researchers in Canada conducted a population-level cohort study using linked administrative databases that included all patients who initiated systemic therapy, including chemotherapy and targeted agents, for a new diagnosis of cancer in Ontario, Canada, from 2007 to 2014. Hospitalization with AKI or acute dialysis was the primary outcome of interest. Study results were reported during a poster session at Kidney Week 2017 in a poster titled AKI in Patients Treated for Cancer: A Population-Based Cohort Study.

Following adjustment for demographics, cancer characteristics, comorbidities, and co-prescriptions, the researchers estimated the cumulative incidence of AKI; fitted Cox proportional hazards models (accounting for the competing risk of death) were also utilized. Exposure to systemic therapy (the 90-day period following each treatment) was modeled as a time-varying covariate. Secular trends were assessed in annual AKI incidence according to year of initiation of systemic therapy.

During the study period, 163,071 patients initiated systemic therapy; of those, 10,880 were hospitalized with AKI. The rate of AKI was 27 per 1000 person-years. One-year, 5-year, and overall cumulative incidences of AKI were 3.9%, 7.8%, and 9.3%, respectively. The highest 5-year rates of AKI incidence were in patients with myeloma (26%), bladder cancer (19%), and leukemia (15%).
There was an association with advanced stage chronic kidney disease (CKD), pre-existing CKD, and diabetes mellitus and increased risk of AKI (adjusted hazard ratios [aHRs], 1.41 [95% confidence interval (CI),1.28-1.45], 1.80 [95% CI, 1.67-1.93] and 1.43 [95% CI, 1.37-1.50], respectively). Among patients ≥66 years of age, there was an association between use of diuretics and angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (ACEi/ARBs) and increased risk of AKI (aHRs, 1.20 [95% CI, 1.14-1.28] and 1.30 [95% CI, .123-1.38], respectively).
There was a significant elevation in AKI risk in the 90 days following exposure to systemic therapy (aHR, 2.34; 95% CI, 2.24-2.45). Between 2007 and 2014, the annual incidence of AKI increased from 18 to 52 per 1000 person-years.

In conclusion, the researchers said, “Cancer-related AKI is common and associated with more advanced stage chronic kidney disease, diabetes mellitus, and the concomitant receipt of diuretics of ACEi/ARBs. Risk is heightened in the 90 days after systemic therapy. Preventive strategies are needed to address the increasing burden of AKI in this population.”
Source: Kitchlu A, McArthur E, Amir E, et al. AKI in patients treated for cancer: a population-based cohort study. Abstract of a poster presented at the American Society of Nephrology 2017 Kidney Week, November 3, 2017, New Orleans, Louisiana.