The incidence of osteoporotic fractures at the University Hospital of Tartu, Estonia

Clinical risk factors for recurrent fracture after hip fracture: a prospective study

Additional fractures after hip fracture are common, but little is known about the risk factors associated with these events. We determined the clinical risk factors associated with fracture following a low-trauma hip fracture and whether clinical risk factors for subsequent fracture were modified by zoledronic acid (ZOL). In this post hoc analysis of the HORIZON Recurrent Fracture trial, 2,127 men and women were randomized within 90 days of surgical hip fracture repair to receive intravenous ZOL 5 mg yearly or placebo. All patients received a loading dose of vitamin D and daily oral calcium and vitamin D supplements. In the multivariable model age, sex, BMI, femoral neck T score, and one or more fall risk factors were significant predictors of subsequent fracture. Race, history of prior fracture other than the index hip fracture, T score < -2.5 as a dichotomous variable, and type of index hip fracture were not associated with a different risk of subsequent fractures. Treatment with ZOL did not modify the impact of these risk factors. Well-established risk factors for fracture risk such as age, sex, BMI, and fall risk factors will also contribute to fracture risk in patients who have already suffered a hip fracture, while other prior fractures and T score < -2.5 are not predictive of subsequent fractures. Baseline risk factors in hip fracture patients were predictive of fracture in both ZOL- and placebo-treated participants, and there is no difference in the risk of subsequent fractures based on index hip fracture type.

Bone mineral density reference range in Estonia: a comparison with the standard database (NHANES III)

Dual-energy X-ray absorptiometry (DXA) is accepted as a standard for diagnosing osteoporosis. Several databases are available for T-score calculation worldwide. Our aim was to compare hip bone mineral density (BMD) in young Estonian adults with the mean BMD in the National Health and Nutrition Examination Survey (NHANES) femur database and to compare the performance of these 2 databases. A population sample of 304 subjects was analyzed with a Lunar DPX-IQ DXA machine (GE Lunar Co., Madison, WI). Seventy-seven healthy young individuals were selected based on their age (25-39 yr). Their femur neck, trochanter, and total hip mean standardized BMD was compared with the corresponding data from the NHANES III database. Diagnostic agreement was assessed in a population sample of adults and in a clinical convenience sample from the densitometry unit. The BMD in the proximal femur in healthy young Estonian adults did not differ from the mean BMD in the NHANES subjects (p > 0.05). Differences in diagnosing osteoporosis and osteopenia are present if the Estonian reference database is used instead of the US standard database. Prospective studies with fracture data for assessing the predictive capability of these reference databases and the additional benefit of adding the FRAX (World Health Organization Collaborating Centre for Metabolic Bone Diseases, University of Sheffield, UK) tool to fracture prediction and osteoporosis diagnosis are needed in Estonia.

Risk factors for fractures of the proximal humerus: results from the EPIDOS prospective study

Fracture of the proximal humerus is one of the most frequent fractures attributable to osteoporosis; yet, it has seldom been studied. Two types of factors (related to bone fragility and falls) were evaluated to identify risk factors for proximal humerus fractures as well as to examine possible interactions between them. Subjects were 6901 white women aged > or =75 years and all participated in the EPIDOS study of risk factors for osteoporotic fractures (France, 1992-1998). The baseline examination included measurements of femoral neck bone mineral density (BMD) and calcaneal ultrasound parameters (speed of sound [SOS] and broadband ultrasound attenuation [BUA]), a functional clinical examination, and completing a questionnaire on health status and lifestyle. During a mean of 3.6 (0.8) years of follow-up, 165 women had a humeral fracture. Using multivariate Cox regression models, we identified three predictors related to bone fragility-low BMD (relative risk [RR] = 1.4; 95% CI, 1.1-1.7), low SOS (RR = 1.3; 95% CI, 1.0-1.6), and maternal history of hip fracture (RR = 1.8; 95% CI, 1.0-3.0)-and four fall-related predictors-a previous fall (RR = 3.0; 95% CI, 1.5-6.1), a low level of physical activity (RR = 2.2; 95% CI, 1.1-4.4), impaired balance (RR = 1.8; 95% CI, 1.1-2.9), and pain in lower limb extremity (RR = 1.4; 95% CI, 1.0-2.1). The effect of these fall-related predictors varied according to the BMD level; they were significantly associated with proximal humerus fractures in women with osteoporosis (BMD T score < -2.5) but not in nonosteoporotic women. The incidence of proximal humerus fracture in women with osteoporosis and a low fall risk score (5.1 per 1000 woman-years) was only slightly higher than in nonosteoporotic women (4.6 per 1000 woman-years) and similar to the incidence in women without osteoporosis but a high fall risk score (5.3 per 1000 woman-years). On the other hand, the incidence in women who had both types of risk factors was more than two times higher (12.1 per 1000 woman-years) than in women with only one of the two risk factors. These results suggest that women who have both types of risk factors should receive the highest priority for prevention.