Association of erythropoiesis-stimulating agents and the incidence risk of cancer diagnosis among chronic dialysis patients: a nested case-control study.

BACKGROUND

Erythropoiesis-stimulating agents (ESAs) are the cornerstone of the treatment for anemia in end-stage renal disease (ESRD) patients. Although a correlation has been established between ESAs and increased tumor growth among patients with cancer-related anemia, an association with a higher incidence of cancer among chronic dialysis patients remains relatively unclear.

METHODS

We completed a nested case-control study in a cohort of 4574 patients who began chronic dialysis treatment between 1 January 2001 and 31 December 2007 in Quebec, Canada, utilizing dialysis registry and administrative databases exclusively to extract our data. We excluded patients with a prior diagnosis of cancer. Eligible cases were identified by the time of initial cancer diagnosis obtained from either the hospital's discharge or physician billing form. We then randomly selected up to 10 controls for each case. ESA exposure was evaluated between 6 and 9 months prior to the initial cancer diagnosis. The mean weekly exposure was used to categorize ESA usage as either a low dose (<30 µg/week), moderate dose (30-70 µg/week) or high dose (>70 µg/week). We estimated the association between ESAs and the risk of developing cancer using a multivariable conditional logistic regression.

RESULTS

We identified 419 cases of cancer and 3895 matched controls during the study period. The use of ESAs was associated with a higher risk of cancer {odds ratio [OR] 1.04 [95% confidence interval (CI) 1.02-1.07]}. Specifically, patients in the high exposure group (>70 µg/week) had an increased risk of developing cancer [OR 1.77 (95% CI 1.18-2.66)] compared with patients in the unexposed group.

CONCLUSION

High-dose ESA was associated with an increased incidence risk of new cancer diagnosis among chronic dialysis patients.