Curtis J R, Westfall A O, Cheng H, Delzell E, Saag K G
Center for Education and Research on Therapeutics of Musculoskeletal Disorders, University of Alabama at Birmingham, Birmingham, AL, USA.
Osteoporos Int. 2008 Nov;19(11):1613-20. doi: 10.1007/s00198-008-0604-4. Epub 2008 May 16.
Based upon interest in a bisphosphonate drug holiday, we evaluate the risk for hip fracture after bisphosphonate discontinuation. Among women compliant with bisphosphonates for > or = 2 years, the risk of hip fracture was increased after discontinuation, although with higher compliance and a longer duration of preceding bisphosphonate therapy, this risk was attenuated.
Recent data suggest that hip fracture risk was not significantly increased among women receiving 5 years of bisphosphonate therapy who were subsequently randomized to placebo. We studied older women compliant with bisphosphonates > or = 2 years to evaluate the risk of hip fracture after bisphosphonate discontinuation.
Using administrative databases from a large U.S. healthcare organization, we identified women initiating bisphosphonate therapy compliant (Medication Possession Ratio, MPR > or = 66%) for 2 years. We examined the rate of hip fracture among women who discontinued bisphosphonates versus those who remained on therapy.
At 2 years, 9,063 women were eligible for analysis. Hip fracture incidence among women who discontinued bisphosphonates versus those who did not was 8.43 versus 4.67 per 1000 person years (p = 0.016). The adjusted hazard ratio of hip fracture per 90 days following discontinuation was 1.2 (1.1-1.3). For women with higher compliance at 2 years (MPR > or = 80%) or compliant for 3 years, there were no significant differences in risk associated with discontinuation.
The rate of hip fracture was increased among women compliant with bisphosphonate therapy for 2 years who subsequently discontinued, suggesting that discontinuation is not advisable under these conditions. This association was attenuated with higher compliance and a longer duration of previous bisphosphonate therapy.
基于对双膦酸盐药物假期的关注，我们评估了停用双膦酸盐后髋部骨折的风险。在依从双膦酸盐治疗≥2年的女性中，停药后髋部骨折风险增加，尽管依从性越高且先前双膦酸盐治疗持续时间越长，这种风险会降低。
近期数据表明，接受5年双膦酸盐治疗后随即被随机分配至安慰剂组的女性，其髋部骨折风险并未显著增加。我们研究了依从双膦酸盐治疗≥2年的老年女性，以评估停用双膦酸盐后髋部骨折的风险。
利用美国一家大型医疗保健机构的管理数据库，我们确定了开始双膦酸盐治疗且依从性良好（药物持有率，MPR≥66%）达2年的女性。我们比较了停用双膦酸盐的女性与继续接受治疗的女性的髋部骨折发生率。
2年后，9063名女性符合分析条件。停用双膦酸盐的女性与未停用的女性相比，髋部骨折发生率分别为每1000人年8.43例和4.67例（p = 0.016）。停药后每90天髋部骨折的调整风险比为1.2（1.1 - 1.3）。对于2年依从性较高（MPR≥80%）或依从3年的女性，停药相关风险无显著差异。
依从双膦酸盐治疗2年随后停药的女性中，髋部骨折发生率增加，这表明在这些情况下停药不可取。这种关联随着依从性提高和先前双膦酸盐治疗持续时间延长而减弱。
