incidence of bone fracture among osteoporotic women during a six-year period of follow-up and its relation to type of therapy

background and objective: due to a high prevalence of osteoporosis and its costs and regarding different ways of treatment for this disease and lack of knowledge about their efficacy in fracture rate in iran, this study was designed in zanjan to determine fracture rate in hypogonadal osteoporotic women who were on different types of anti-osteoporotic treatments. materials and methods: in this historical cohort study, 160 osteoporotic women were investigated. they were under treatment for their osteoporosis during 2001-2007. the cases were divided into 4 groups based on their type of treatment: 1) calcium 1000 mg/daily + vit d 200 iu/daily 2) calcium 500 mg/daily + vit d 200 iu/daily + alendronate 10 mg/daily 3) hrt with calcium d 4) combination therapy. one group that didn't receive any type of treatment, were considered as control group. at least two densitometries were carried out in each case that the first one being done at the beginning of the study. bone density was measured in three sites including: hip, spine and forearm with dexa method. the rate of osteoporotic fractures was investigated in any site of the body during the follow-up period based on patient's invitation and their documents. data were analyzed using chi square, t-test, logistic regression and kaplan-meier survival curve. results: the rate of fracture was 11% (18 cases). most of the fractures were non-vertebral (17 cases) and occurred in ages less than 50 years (17.9%). the most effective treatment to reduce fracture rate was alendronate (with 69.9% reduction rate). hrt was as effective as calcium and vit d in reducing the fracture rates. bone density in forearm region was known as the most vigorous predictive factor of fracture rate in our study. most of the fractures were reported in forearm and leg regions (63.3%). conclusion: based on this study it can be concluded that alendronate is the most effective treatment to reduce fracture rate in osteoporotic women. densitometry is also recommended for women under 50 years old with hypogonadysm for early diagnosis and treatment. keywords: osteoporosis- fragility fracture, densitometry, hrt, calcium d, bisphosphonate.