How Bisphosphonates play role in Osteoporosis
Osteoporosis is a bone disease that occurs when the body loses too much bone or makes too little bone. It causes the bones to become weak and brittle, in a way that a fall or even mild stresses such as bending over or coughing can cause a fracture. Osteoporosis related fractures most commonly occur in the hip, wrist or spine.
It occurs when the creation of new bone doesn't keep up with the removal of old bone. To prevent fractures, sometimes bisphosphonates are prescribed as the first line treatment. In order to analyze the available evidence on the efficacy of bisphosphonates for preventing fractures, a study was conducted.
In this randomized trial of 36 studies for comparing any bisphosphonate with other bisphosphonate or placebo, Cochrane Library, Embase and Pubmed and manually searched reference list of relevant articles were studied. Pairwise and network meta-analyses were performed. The primary outcome was vertebral fracture. Secondary outcomes included the non-vertebral fracture, hip fracture, wrist fracture and any fracture.
After trial, significant difference was found between bisphosphonates for vertebral fracture and non-vertebral fracture. Compared with placebo, alendronate, clodronate, ibandronate, minodronate, pamidronate, risedronate, and zoledronic acid significantly prevented vertebral fracture. However, zoledronic acid significantly reduced the risk of vertebral fracture compared with alendronate, clodronate, etidronate, ibandronate, risedronate, and tiludronate (0.65 (0.46, 0.91), 0.53 (0.33, 0.86), 0.45 (0.27, 0.74), 0.52 (0.36, 0.75), 0.59 (0.42, 0.83), and 0.31 (0.21, 0.48), respectively). Whereas, when compared with etidronate, clodronate and zoledronic acid significantly prevented nonvertebral fracture and when compared with alendronate, zoledronic acid significantly prevented any fracture. The possibility rankings showed that zoledronic ranked first in preventing vertebral fracture, hip fracture, and any fracture, and pamidronate ranked first in preventing nonvertebral fracture and wrist fracture. In the sensitivity analyses, zoledronic acid ranked first in preventing nonvertebral fracture, and alendronate ranked first in preventing hip fracture and wrist fracture.
It was observed that zoledronic acid seemed to be the most effective in prevention of vertebral fracture, nonvertebral fracture and any type of fracture. Whereas, alendronate or zoledronic acid seemed the most effective in the prevention of hip fracture. However, uncertainty still remains and future studies are still needed to accurately evaluate the comparative efficacy of bisphosphonates.