Einfluss einer Therapie mit 2,5 mg Tibolon im Vergleich zu einer niedrig dosierten kombinierten Hormontherapie mit 1 mg Estradiol und 0,5 mg Norethisteronacetat auf die Messwerte der DXA und QUS bei postmenopausalen Frauen.

The primary objective of this study was to determine whether there was a difference in the skeletal benefits between the two medications: 1 mg E2 + 0.5 mg NETA and 2.5 mg Tibolone. Presently the “goldstandard” to diagnose Osteoporosis is the dual X-ray absorptiometry (DXA) measurement of the bone mineral density. However, another method, quantitive ultrasonometry (QUS), which is safe, free of radiation, cheaper and portable appears to also be an effective diagnostic tool. We conducted our measurements over two years at Baseline, after 6, 12 and 24 months in total using four DXA scans consisting of lumbar spine, femoral neck, hip and total body (Prodigy, GE/Lunar), and four QUS scans consisting of both Calcaneus (Achilles Insight, GE/Lunar) and Phalanges (Bone-Profiler, IGEA). Furthermore our secondary objective was to evaluate to which extent over the course of twenty-four months our DXA measurement results correlated with our QUS measurement results. Patients and methods: A monocentric study at the University Hospital in Marburg with fifty postmenopausal women who were prescribed HT in order to alleviate menopausal symptoms was performed. Each patient was randomised either to the 1 mg E2 + 0.5 mg NETA or the 2.5 mg Tibolone group, whereby in total after 24 months eighteen Patients per group remained. In the following two years each patient received four DXA scans consisting of lumbar spine, femoral neck, total hip and total body, and four QUS scans consisting of both Calcaneus and Phalanges at Baseline, and after 6, 12 and 24 months. Results and Conclusion: In comparison over the two years using the DXA BMD measurements both groups showed a significant increase in the lumbar spine, whereby for 1 mg E2 + 0.5 mg NETA group the BMD increased by 4% (p=0.994) and for 2.5 mg Tibolone the BMD increased by 3.7% (p=0.025). The difference in increase compared between the two groups was non-significant. The statistical significant increase in BMD using the DXA scan was not so seen in the femoral neck, total hip and total body nor in the QUS scans of calcaneus und phalanges. At the femoral neck and total hip using the DXA scan a significant increase in BMD was only seen in the 1 mg E2 + 0.5 mg NETA group (femoral neck = 1.1% (p=0.031) and total hip = 1.1% (p=0,004)). Overall the 1 mg E2 + 0.5 mg NETA group tends to, although not significantly, show a greater and faster increase in BMD when compared to 2.5 mg Tibolone. With regard to our result the use of QUS (calcanues und phalanges) as a method for therapy measurements today, cannot be recommended. Further randomised studies are needed to investigate this relation.