Effects of short-term use of ibuprofen or acetaminophen on bone resorptionin healthy men: A double-blind, placebo-controlled pilot study

Prostaglandins are known to be involved in the metabolism of bone, having a significant influence on bone resorption in cases of bone pathology. We th erefore investigated the shortterm effects of two commonly used nonsteroida l anti-inflammatory drugs (NSAIDs), ibuprofen and acetaminophen (paracetamo l), on bone resorption in healthy men. In a randomized, double-blind pilot study, 28 healthy, age- and weight-matched male volunteers were treated wit h ibuprofen (n = 10), acetaminophen (n = 9), or a placebo (n = 9) for 3 day s. As an indication of bone resorption rate, levels of the biochemical bone markers N-telopeptide (NTx) and free deoxypyridinoline (D-Pyr) were measur ed in urine. Differences in resorption marker levels pre- and post-NSAID us e were then compared between groups. We found that NTx concentrations in th e acetaminophen group were lower than placebo (p = 0.048), whereas NTx leve ls in the ibuprofen group were higher than in the acetaminophen group (p = 0.016). By contrast, D-Pyr concentrations in the ibuprofen group were signi ficantly lower than in the placebo group (p = 0.009). A comparison of the p ercentage changes of D-Pyr:NTx ratios found that the ratio in the ibuprofen group was significantly lower than that of both the control (p = 0.0065) a nd acetaminophen (p = 0.01) groups. These results show the differential eff ects of ibuprofen and acetaminophen on urinary excretion of peptide-hound a nd free deoxypyridinoline crosslinks of type I collagen. Short-term ibuprof en use may alter the renal handling of collagen cross-links and increase bo ne resorption to a greater extent than acetaminophen in normal men. (C) 200 1 by Elsevier Science Inc. All rights reserved.