Analgesic use and change in kidney function in apparently healthy men

Studies using a single creatinine measurement have yielded inconsistent results regarding analgesic use and kidney function.

This is a prospective cohort study of 4,494 US male physicians who provided blood samples in both 1982 and 1996. Outcomes measured were increase in plasma creatinine level of 0.3 mg/dL or greater (> or =26.5 micromol/L) and decline in glomerular filtration rate (GFR) of 29.0 mL/min/1.73 m2 or greater during this 14-year period. Self-reported use of aspirin, acetaminophen, and other nonsteroidal anti-inflammatory drugs (NSAIDs) was classified as never (<12 pills during the study period), 12 to 1,499 pills, 1,500 to 2,499 pills, and 2,500 or greater pills during the study period.

Blood measurements made 14 years apart showed increased creatinine levels in 242 participants and decreased GFRs in 224 participants. Compared with never use, multivariable-adjusted odds ratios (ORs) of increased creatinine levels were 0.98 (95% confidence interval [CI], 0.43 to 2.23) for 2,500 or greater pills of aspirin, 1.02 (95% CI, 0.55 to 1.90) for 2,500 or greater pills of acetaminophen, and 1.12 (95% CI, 0.67 to 1.87) for 2,500 or greater pills of other NSAIDs. For decreased GFRs, ORs for intake of 2,500 or greater pills were 0.75 (95% CI, 0.35 to 1.57) for aspirin, 1.22 (95% CI, 0.66 to 2.26) for acetaminophen, and 1.11 (95% CI, 0.65 to 1.90) for other NSAIDs. Use of aspirin, but not acetaminophen or other NSAIDs, was associated with a reduced risk for change in kidney function in participants without cardiovascular risk factors and a possible but nonsignificant increase in those with cardiovascular risk factors.

Occasional to moderate analgesic intake of aspirin, acetaminophen, or NSAIDs does not appear to increase the risk for decline in kidney function during a period of 14 years.