Table 3.
Change from baseline in bone microarchitecture parameters evaluated by HR-pQCT.
| Month | Abatacept (N = 15) | csDMARDs (N = 20) | Adjusted mean difference (Abatacept – csDMARDs) [95%CI], P value |
|---|---|---|---|
| Mean change from baseline (SD) | Mean change from baseline (SD) | ||
| Tb.vBMD, mg/cm3 | |||
| 6 | − 0.89 (10.79) | − 7.90 (19.56) | 3.46 [− 3.97, 10.88], P = 0.355 |
| 12 | − 1.63 (13.43) | − 5.26 (21.57) | 1.22 [− 7.37, 9.81] P = 0.778 |
| BV/TV, % | |||
| 6 | − 0.15 (1.71) | − 1.15 (2.81) | 0.62 [− 0.46, 1.71], P = 0.254 |
| 12 | − 0.31 (1.99) | − 0.86 (2.91) | 0.38 [− 0.87, 1.63], P = 0.548 |
| Tb.N, 1/mm | |||
| 6 | − 0.03 (0.10) | − 0.02 (0.08) | 0.02 [− 0.02, 0.06], P = 0.368 |
| 12 | − 0.01 (0.07) | − 0.01 (0.10) | 0.02 [− 0.03, 0.07], P = 0.399 |
| Tb.Sp, µm | |||
| 6 | 13.26 (26.26) | 11.38 (37.75) | − 14.75 [− 32.49, 2.99], P = 0.101 |
| 12 | 15.53 (23.33) | 13.44 (46.60) | − 15.29 [− 35.49, 4.91], P = 0.136 |
| Tb.Th, µm | |||
| 6 | − 0.3 (5.64) | − 3.38 (8.17) | 0.88 [− 2.94, 4.70], P = 0.645 |
| 12 | − 0.89 (8.02) | − 2.75 (9.10) | − 0.45 [− 4.77, 3.88], P = 0.837 |
The Adjusted mean differences at each time point were estimated using a mixed-effects model. The objective variable was the change from baseline, and the fixed effects were group, time point, multiple term between group and time point, and adjustment variables including age, sex, steroid administration status, rheumatoid arthritis disease duration, RF, and baseline values of the outcome measures. The random effects were the patients.
csDMARDs conventional synthetic disease-modifying antirheumatic drugs, Tb.vBMD trabecular volumetric bone mineral density, BV/TV trabecular bone volume fraction, Tb.N trabecular number, Tb. Sp trabecular separation, Tb.Th trabecular thickness, SD standard deviation, CI confidence interval.