Background The use of nonsteroidal anti-inflammatory drugs (NSAIDs) and Cox-2 inhibitor are known to inhibit synthesis of prostaglandins and may prevent bone loss, but there is no study that shown the distinction between NSAIDs and COX-2 inhibitor on bone mineral density (BMD).We hypothesized the subject of NSAIDs use would be associated with increased BMD than the subject of Cox-2 use.

Objectives The purpose of this study was compared the change of the BMD between NSAID use group and COX-2 inhibitor use group.

Methods Between January 2005 and September 2011, we identified postmenopausal women with osteoporosis (T score >-2.5) and osteoarthritis treated with Cox-2 inhibitor (Celebrex, n=319) and NSAIDs (aceclofenac, n=104), who underwent a BMD measurement by dual-emission X-ray absorptiometry (DXA) every one year and structured interview in the 5th year of this study. The all subjects were taken bisphosphonate and the outcome measure was present difference in BMD (g/m²) and T-score. The affecting factors for elevated BMD evaluated included sex, age, BMI, disease duration, cumulative period of NSAIDs, COX-2 inhibitor and bisphosphonate. After extracting possible affecting factors through univariate analysis, multivariate logistic regression analysis was performed with backward selection to derive affecting model for increased BMD in patients with osteoarthritis.

Results After adjustment for possible confounders, daily use of NSAIDs users were associated with a higher BMD at whole L-spine (2.54% 1.7-3.1 CI) and both hip (1.21%, 0.6-2.4 CI) than Cox-2 inhibitor users. Also, T-score was higher in NSAIDs users than Cox-2 inhibitor users. Univariate analysis revealed that old age (P=0.008), low BMI (P=0.001), and cumulative period of NSAIDs, COX-2 inhibitor and bisphosphonate (P<0.001) were possible affecting factors. Multivariate logistic regression analysis showed that cumulative period of NSAIDs, COX-2 inhibitor and bisphosphonate [odds ratio (OR) 4.86, 95% CI 1.27 - 18.55, P=0.021) are factors for increased BMD in patients with osteoarthritis and osteoporosis.

Conclusions Daily use of NSAIDs is synergistic effect on BMD than daily use of Cox-2 inhibitor in postmenopausal women with osteoporosis treated with bisphosphonate. so our results suggest that NSAIDs use is preferred to use cox-2 inhibitor in patients with osteoporosis and osteoarthritis.

References

1. Osteoporos Int (2006) 17:1410–1419.

Disclosure of Interest None declared