Risk of kidney cancer in analgesics users

The risk of kidney cancer was examined in a cohort of people discharged from Danish hospitals from 1977-1987 with a diagnosis of rheumatoid arthritis, osteoarthrosis or backpain. These individuals are presumably more or less regular users of mild analgesics. A total of 155,554 people were identified. The risk of cancer of the urinary tract was slightly increased [relative risk (RR) = 1.31], almost exclusively because of an increased risk of renal cell carcinoma (RR = 1.40). The relative risk was higher in individuals with rheumatoid arthritis than among individuals with osteoarthrosis or backpain, and higher among women than men. Although this study lacks information on the actual analgesics consumption of the individual, and various biases may be present, these findings offer little support to the concern that increased analgesics use raises the risk of kidney cancer.