Analgesic use and the risk of renal cell carcinoma – Findings from the Consortium for the Investigation of Renal Malignancies (CONFIRM) study

Purpose: The incidence of renal cell carcinoma (RCC) is rising. Use of analgesics such as non-steroidal anti-inflammatory drugs (NSAIDs) and paracetamol may affect renal function. The aim of this study was to assess associations between analgesic use and risk of RCC. Methods: A population-based case-control family design was used. Cases were recruited via two Australian state cancer registries. Controls were siblings or partners of cases. Analgesic use was captured by self-completed questionnaire. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for RCC risk associated with regular analgesic use (at least 5 times per month for 6 months or more) and duration and frequency of use. Results: The analysis included 1064 cases and 724 controls. Regular use of paracetamol was associated with an increased risk of RCC (OR 1.41, 95%CI 1.13–1.77). Regular use of NSAIDs was associated with increased risk of RCC for women (OR 1.71, 95% CI 1.23–2.39) but not men (OR 0.83, 95% CI 0.58–1.18; p-interaction=0.003). There was no evidence of a dose-response for duration of use of paracetamol (linear trend p = 0.77) and weak evidence for non- aspirin NSAID use by women (linear trend p = 0.054). Conclusion: This study found that regular use of paracetamol was associated with increased risk of RCC. NSAID use was associated with increased risk only for women.