Endocrine Abstracts

Backgound: ESRD is associated with reduce bone mineral density compared with aged-matched healthy population. DXA is the standard noninvasive method to assess BMD. It is expensive, needs special equipment, X ray exposure, movement of the patients. QUS is inexpensive, mobile, easy to perform, radiation free, recognize for screening abilities and risk fracture prediction in normal population. This study assessed the ability of QUS versus DXA in determine BMD in haemodialised population.

Materials and methods: Patients randomly selected from all patients active in the evidence of the Haemodialysis and Renal Transplantation Center form the County Hospital no.1, performed DXA (anteroposterior technique, Delphi W device, Hologic Inc.), and also QUS (Sahara device, Hologic Inc.). Correlation between DXA and QUS parameters were performed. Receiver operator characteristic curves (ROC) were plotted for BUA, SOS and QUI and used to define cut-off values for best sensitivities and specificities for all parameter. WHO T score diagnosis of osteoporosis and osteopenia were used. We also used the UK NOS strategy to define the interval of the best QUS diagnostic parameter, to identify with 90% sensitivity and 90% specificity different degrees of bone demineralization.

Results: One hundred and thirty-one patients (63 females and 68 males), mean age 47 776±12, 32 years, being in haemodialysis for a mean period of mean 51 488±4686 months. BU A (r=0.613/0.447) and QUI (r=0.613/0.502) seem to be the parameters of choice when considering BMD at cortical level. Areas under ROC for BUA and SOS in diagnosis of osteoporosis and osteopenia, have a sensibility of 76, 1%-76, 1%, respectively a specificity of 72, 5%-77, 8%. The values for osteoporosis are even better, for 77% and 84%. The identified cutoff levels for QUI are 76.1 (osteopenia) and 69.6 (osteoporosis). The diagnostic value of QUS)when reporting QUI=are even higher when we did define the proper interval.

Conclusion: DXA and QUS parameters correlate significantly. The best QUS diagnostic parameter is QUI. The high negative predictive value of different cut-off point suggests a very good screening power of QUI in identifying cases without bone demineralization. Cut-off values for QUI associated a high sensitivity (between 60 and 80%) respectively specificity of over 75% in diagnosis osteopenia and or osteoporosis. Using the 90–90 approach, we identify the precise interval for QUI values that allows the best diagnostic of bone demineralization.