Table 3. Bone Biomarkers at Baseline and After 3 and 6 Months of LMMS or Placebo in Young Women With Anorexia Nervosa and Those With Percentage of Median BMI of 85% or Less.
| Measure | Baseline median (IQR) | Adjusted median (IQR)a | Median change (IQR) from 0 to 6 mo | P value (within group) | 95% CI for median difference (0-6 mo) within group | P value (difference in change between groups) | 95% CI for difference in median change between groups | |
|---|---|---|---|---|---|---|---|---|
| 3 mo | 6 mo | |||||||
| BSAP, ng/mL | ||||||||
| LMMS | 28.0 (24.8 to 31.8) | 43.3 (36.2 to 55.7) | 36.0 (29.6 to 43.6) | 4.5 (−0.9 to 11.3) | .02 | 1.42 to 10.11 | .28 | −7.98 to 3.77 |
| Placebo | 27.1 (24.3 to 31.9) | 33.3 (13.9 to 45.8) | 34.5 (31.1 to 41.3) | 6.1 (13.9 to 45.8) | .04 | 2.46 to 10.04 | ||
| C-Telopeptides, pmol/L | ||||||||
| LMMS | 0.5 (0.4 to 0.7) | 0.5 (0.4 to 0.6) | 0.5 (0.4 to 0.6) | <0.1 (−0.2 to 0.1) | .83 | −0.15 to 0.12 | .64 | −0.26 to 0.04 |
| Placebo | 0.4 (0.3 to 0.6) | 0.5 (0.4 to 0.51) | 0.5 (0.4 to 0.6) | <0.1 (−0.3 to 0.2) | .28 | −0.04 to 0.16 | ||
| Osteocalcin, μg/L | ||||||||
| LMMS | 25.7 (22.0 to 30.0) | 28.4 (24.8 to 31.2) | 32.2 (30.0 to 37.1) | 5.2 (2.1 to 12.3) | .01 | 2.31 to 11.66 | .40 | −5.61 to 7.48 |
| Placebo | 24.2 (21.0 to 29.2) | 27.7 (25.7 to 31.2) | 29.7 (22.8 to 33.3) | 6.8 (−8.4 to +10.9) | .10 | −3.24 to 8.11 | ||
| Female adolescents with anorexia nervosa with percentage of median BMI of ≤85% (n = 21) | ||||||||
| BSAP, ng/mL | ||||||||
| LMMS | 26.3 (24.0 to 32.1) | 33.9 (30.4 to 38.2) | 30.4 (25.7 to 33.1) | 2.4 (−2.1 to 6.7) | .39 | −2.80 to 8.04 | .04 | 0.17 to 12.89 |
| Placebo | 24.2 (25.5 to 31.4) | 25.1 (24.2 to 28.4) | 26.0 (22.4 to 27.6) | 0.7 (−0.01 to 0.12) | .22 | −1.11 to 5.03 | ||
| C-Telopeptides, pmol/L | ||||||||
| LMMS | 0.47 (0.36 to 0.54) | 0.41 (0.39 to 0.42) | 0.53 (0.44 to 0.55) | 0.07 (−0.01 to 0.12) | .39 | −0.02 to 0.13 | .70 | −0.16 to 0.34 |
| Placebo | 0.41 (0.32 to 0.62) | 0.41 (0.39 to 0.42) | 0.46 (0.43 to 0.53) | 0.06 (−0.28 to 0.14) | .85 | −0.26 to 0.15 | ||
| Osteocalcin, ng/mL | ||||||||
| LMMS | 22.1 (19.2 to 25.6) | 24.9 (23.4 to 26.4) | 29.2 (23.4 to 26.4) | 6.1 (−0.3 to 10.4) | .07 | −2.00 to 10.97 | .06 | −8.83 to 14.08 |
| Placebo | 24.4 (19.5 to 34.1) | 25.4 (23.2 to 26.0) | 25.8 (24.8 to 28.1) | 1.1 (−7.7 to 3.9) | .67 | −8.65 to 4.75 | ||
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); BSAP, bone-specific alkaline phosphatase; LMMS, low-magnitude mechanical signals.
SI conversion factors: To convert osteocalcin to micrograms per liter, multiply by 1.
a
Adjusted for patient age, duration of anorexia, weight gain from 0 to 6 months, and adherence (median platform-recorded minutes used per 3-month period).