PTH and Vibration in OSteoporosis Study

Study Objectives

• To determine if WBV in addition to standard PTH treatment has a greater effect on bone mass in osteoporosis patients compared to standard PTH treatment alone.
• To determine if WBV in addition to standard PTH treatment has a greater effect on bone microarchitecture in osteoporosis patients compared to standard PTH treatment alone, as assessed by high resolution peripheral quantitative computed tomography (HR-pQCT).
• To determine if WBV in addition to standard PTH treatment has a greater effect on markers of bone formation and resorption in osteoporosis patients compared to standard PTH treatment alone.
• To study the effects of WBV on muscle function and balance in osteoporosis
• To assess the safety and adherence to WBV in osteoporotic patients

Study Design:

General Design This will be a multi-center randomized controlled trial (RCT) in osteoporosis patients being started on standard PTH treatment according to Danish Osteoporosis guidelines. Participants will be randomized to standard PTH treatment alone or to standard PTH treatment and WBV.

Statistical Plan:

Sample Size Determination The inclusion of 32 participants (16 in both groups) would give the study 80% power to detect a clinically significant additional increase of 22% with WBV (assuming a 9% increase of BMD in the PTH alone group and 11% increase in the combined PTH+WBV group, and assuming a SD of the BMD increase of 2%. Allowing for a 20% dropout rate, the plan is to include 40 participants (20 in each group). From previous research on WBV by one of the investigators (TM), statistically significant differences were found in bone formation markers and in muscle strength at 3 months between the WBV and control groups with a sample size of 35. The number of participants in the latter pilot work is reassuringly consistent with the sample size calculations. The number needed to be included is far less (34%) than the actual number of patients treated with PTH in the recruiting departments in a similar time period last year.

Statistical Methods:

STATA/SPSS will be used for data analysis. For the primary endpoint (BMD at 12 months) the mean percentage changes in BMD between the two groups will be compared using Analysis of Variance (ANOVA) provided the distribution is normal. For the other endpoints parametric tests will be used to assess differences in the two groups for normally distributed data and non-parametric tests for data not normally distributed.

The randomization will be done online in the data capture program Red Cap. There will be created a Data dictionary that contains detailed descriptions of each variable used by the registry, including the source of the variable, and normal ranges if relevant.

Information:

Participants will be recruited during their attendance at the outpatient clinics. At that time the subjects will be given a full explanation of the study as well as the patient information sheet and invited to participate in the study. At an interval of not less than 24 hours, patients will be invited to consent prior to starting their PTH treatment.

The information will be sufficient for subjects to make an informed decision about their participation in this study. The subject will complete and sign a consent form to indicate they are giving valid consent to participate in the trial.

Withdrawal of Subjects:

Patients who withdraw consent from participation in the trial will be withdrawn from the trial. This will not affect their standard medical management and not cause any adverse effect on the subject.

Inclusion criteria

• Women starting PTH treatment for osteoporosis according to Danish Osteoporosis guidelines

Exclusion criteria

• Women currently taking oral glucocorticoids
• Women unable to give informed consent
• Women unable to stand for 2 minutes at a time on the vibration platform
• Women who have contraindications to WBV (e.g. joint prosthesis, pacemakers)