Analgesic use and risk of renal cell cancer: Results from two prospective cohort studies.

Abstract

588 Background: The relationship between the widely used analgesics (i.e., aspirin, other nonsteroidal anti-inflammatory drugs (NSAID), and acetaminophen) and risk of total and lethal renal cell cancer remains unclear. Methods: We examined the associations between analgesic use and risk of renal cell cancer overall and by subtypes, in the Nurses’ Health Study (NHS) and the Health Professionals Follow-up Study (HPFS). We collected information on aspirin, other non-aspirin NSAIDs, and acetaminophen in 1990 in the NHS and in 1986 in the HPFS, and every 2 years thereafter. We used Cox proportional hazards models, controlling for other known and suspected risk factors, to examine the associations between baseline and duration of use of each analgesic and risk of total renal cell cancer, lethal renal cell cancer (resulted in death due to disease), as well as clear cell renal cell cancer. We pooled results using a random-effects model. Results: During follow-up of 22 years among 77,527 women and 26 years among 45,913 men, we documented 438 cases of renal cell cancer (230 in women and 208 in men), of which 106 were fatal (56 in women and 40 in men) and 300 were clear cell (165 in women and 135 in men). The pooled multivariable relative risks (RRs) for total renal cell cancer were 1.13 (95% CI: 0.91-1.39) for aspirin use, 1.34 (95% CI: 1.03-1.75) for non-aspirin NSAID use, and 1.07 (95% CI: 0.80-1.44) for acetaminophen use. Similar results were observed for lethal renal cell cancer and clear cell renal cell cancer. Importantly, longer duration of non-aspirin NSAID use was associated with an increased risk of renal cell cancer. The pooled (all p-heterogeneity > 0.05) multivariable RRs for total renal cell cancer were 1.23 (95% CI: 0.94-1.62) for non-aspirin NSAID users of 4-10 years and 1.81 (95% CI: 1.21-2.72) for over 10 years. The corresponding RRs were 1.91 (95% CI: 1.04-3.49) and 3.97 (95% CI: 1.46-10.83) for lethal renal cell cancer, and 1.36 (95% CI: 0.99-1.88) and 1.58 (95% CI: 0.94-2.63) for clear cell renal cell cancer. Conclusions: Our findings support a significant positive association between non-aspirin NSAID use and risk of developing renal cell cancer, especially the lethal form.