DVO- and FRAX-Score for major osteoporotic fracture – identification of the same male patients in need of therapy?

Introduction Different national and international scores are in use to evaluate the osteoporotic fracture probability in men. The DVO-Score is mainly established in Germany and calculates the 10-year-fracture probability for hip and vertebral fracture, whereas the FRAX-Score is adopted worldwide. FRAX calculates a 10-year-fracture-probability for four subscores (major osteoporotic fracture [MOF] and hip fracture [HF] with or without including bone mineral density [BMD]). MOF refers to vertebral-, hip-, shoulder- and wrist-fractures. The FRAX algorithm is not published and only integrates the BMD at the femoral neck (FN).

Methods This seven year retrospective study is based on data analysis from the MVZ endocrinological center in Göttingen. 130 male patients, at an average age of 59.21 ± 11.77 years, met the study requirements. We used DVO- and FRAX-Score for MOF with BMD to calculate the 10-year-fracture probability. Additionally, we used linear regression to evaluate the FRAX-Score risk factors (RF) in respect of their loading in the FRAX algorithm. We used a therapeutic threshold of > 30% for the DVO-Score. For FRAX-Score for MOF we adapted the internationally mostly used therapy threshold ≥ 20%. Linear regression was applied to analyse risk factors with highly significantly (p ≤ 0.01) influence on FRAX-Score for MOF. Finally, we compared patient specific therapy recommendations of the two scores.

Results 60.8 % of the male patients referring to DVO-Score and 13.1 % referring to FRAX-Score for MOF were identified for treatment. 94 % of patients in need of therapy recording to FRAX-Score for MOF had a highly significant risk factor (hsRF). One patient with treatment recommendation without a hsRF had a T-Score of -3.6 at the FN. The T-Score at FN had also a highly significant loading (p ≤ 0.01) in the linear regression. DVO-Score identified 63 patients in need of therapy which were not identified by FRAX-Score for MOF. These patients had an average T-Score at FN of -2.0. FRAX-Score for MOF identified only one patient for treatment which was not similarly classified by DVO-Score. This patient at an age of 63 had two hsRF according to linear regression and a T-Score at FN of -2.85.

Discussion According to FRAX Score for MOF the BMD at the FN had a very strong influence on the algorithm (regression coefficient -6.64). Other risk factors, such as age (p = 0.29), body mass index (p = 0.29), current smoking (p = 0.94) and secondary osteoporosis (p = 0.04) did not have a highly significant influence on the algorithm when including BMD. The DVO-Score classified fracture risk applying BMD in addition to age. Conclusively the scores identify different male patients with indication for therapy, in our male patients the difference predominantly dependent on the RF age and BMD. We suggest careful consideration of the appropriate score in the daily care, especially in young male patients.

Keywords bone, FRAX-Score, DVO-Score, osteoporosis in men

Korrespondenzadresse Judith Charlotte Witzel, Universitätsmedizin Göttingen, Institut für Diagnostische und Interventionelle Radiologie, Robert-Koch-Straße 40, 37075 Göttingen, Deutschland,

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