Osteogenesis imperfecta (OI) is a rare genetic disease affecting structure or quantity of type I collagen in bone and skin. OI has a wide spectrum of severity with the most common presentation of fragile bones. There is still no cure for OI, however studies showed that bisphosphonate confers some benefits. Our aims are to know the characteristics of OI patients and the correlation between the frequency of bisphosphonate therapy and fracture after therapy.
This was a cross sectional study from OI registry database in Cipto Mangunkusumo Hospital. Acquired data from registry and medical record were analyzed.
There were 29 OI patients receiving bisphosphonate IV therapy that is pamidronic or zolendronic acid with sufficient data, out of which 51.7% were female. The age at diagnosis was 1.5 (0-10) years. The most common type of OI was type III (60%). Only 8 patients (27.6%) had family history of OI. All patients had clinical manifestations of multiple fractures and long bone deformations, 21 patients (72.4%) presented with blue sclera and 14 patients (48.3) with spine deformation. Almost all patients had short stature (93.1%). The duration of therapy was 2 (0-10) years. The frequency of bisphosphonate IV therapy was 4 (1-19) times. The fracture frequency before and after therapy decreased from 5 (1-20) to 1 (0-10). However, this study also found that there was significant moderate correlation between bisphosphonate IV frequency and fracture frequency after therapy (p =0.048).
The frequency of fracture increase along with the frequency of bisphosphonate administration. Further studies should be conducted to determine the risk factors of fracture occurrences after bisphosphonate therapy, such as increased activity. Our study did not include bone mineral density (BMD) to determine bone improvement as it is not routinely measured because it was not yet covered by the government.