Bisphosphonates and osteoporotic fractures: a cross-design synthesis of results among compliant/persistent postmenopausal women in clinical practice versus randomized controlled trials

Abstract

In a cross-design synthesis, total fractures were similarly reduced by bisphosphonates among postmenopausal women in randomized trials (23.8%) and highly compliant/persistent patients in observational studies of large databases from routine practice (20.3%). Bisphosphonates also reduced nonvertebral, vertebral and hip fractures in randomized trials and observational studies. In the real-word setting, compliant/persistent patients can gain a benefit from bisphosphonates comparable to that of randomized trial participants.

Introduction: The purpose of the study was to determine whether clinical fracture risk reduction by bisphosphonate treatment in women with postmenopausal osteoporosis differs between randomized controlled trials and routine practice.

Methods: Randomized trials comparing bisphosphonate with placebo and observational studies comparing highly compliant/persistent with less compliant/persistent patients were sought by electronic searches and ancillary methods. Clinical fracture data were extracted from the study reports and quantitatively combined by random effects metaanalysis.

Results: The odds ratio (OR) for all clinical fractures in randomized trials of 0.762, with a 95% confidence interval (CI) of 0.680-0.855, was closely similar to that in the observational studies (OR, 0.797; CI, 0.748-0.850). Pooled clinical fracture reduction across both study designs was 22%. Nonvertebral, vertebral, and hip fractures were also significantly reduced by bisphosphonate treatment in both randomized trials and observational studies.

Conclusions: Compliant/persistent patients in the "real-world" setting benefit from bisphosphonate treatment to a similar extent as patients in randomized trials.