Table 2.
MRI outcomes for lesion component/segment‐level analyses.
| Bexarotene | Placebo | Bexarotene‐placebo change | ||||
|---|---|---|---|---|---|---|
| Lesion number | Unadjusted mean (SD) change in component/segment lesional MTR (pu) | Lesion number | Unadjusted mean (SD) change in component/segment lesional MTR (pu) | Adjusted bexarotene‐placebo difference (95% CI) | p‐value | |
| Lesion components (defined spatially) | ||||||
| Core (innermost) pure WM lesions | 695 | −0.04 (2.17) | 414 | −0.09 (1.71) | 0.07 (−0.42, 0.56) | 0.773 |
| Rim pure WM lesions | 1003 | 0.01 (1.79) | 610 | 0 (1.48) | 0.11 (−0.38, 0.59) | 0.665 |
| Cuff 1 pure WM lesions | 997 | −0.02 (1.6) | 608 | −0.06 (1.33) | 0.14 (−0.34, 0.63) | 0.566 |
| Cuff 2 pure WM lesions | 1002 | −0.04 (1.5) | 610 | −0.07 (1.27) | 0.13 (−0.36, 0.61) | 0.613 |
| Cuff 3 (outermost) pure WM lesions | 1002 | −0.02 (1.45) | 610 | −0.06 (1.22) | 0.13 (−0.36, 0.61) | 0.602 |
| Interaction test comparing treatment group differences between the components | 0.807 | |||||
| Core (innermost) pure CGM lesions | 20 | 0.27 (4.58) | 14 | 0.16 (2.82) | 0.01 (−1.41, 1.43) | 0.993 |
| Rim pure CGM lesions | 46 | 1.12 (2.69) | 39 | −0.23 (3.19) | 1.27 (0.05, 2.48) | 0.053 |
| Cuff 1 pure CGM lesions | 46 | 0.77 (2.37) | 39 | −0.69 (2.38) | 1.37 (0.15, 2.58) | 0.038 |
| Cuff 2 pure CGM lesions | 46 | 0.83 (2.51) | 39 | −0.25 (1.91) | 0.98 (−0.23, 2.20) | 0.127 |
| Cuff 3 (outermost) pure CGM lesions | 46 | 0.63 (2.55) | 39 | 0 (1.72) | 0.57 (−0.65, 1.78) | 0.369 |
| Interaction test comparing treatment group differences between the components | 0.042 | |||||
| Core (innermost) pure DGM lesions | 5 | −0.64 (1.65) | 6 | −1.93 (1.82) | 2.09 (0.20, 3.99) | 0.063 |
| Rim pure DGM lesions | 7 | 0.47 (2.82) | 9 | −1.63 (1.42) | 2.37 (0.63, 4.10) | 0.029 |
| Cuff 1 pure DGM lesions | 7 | 0.28 (0.18) | 9 | −1.5 (1.44) | 2.49 (0.74, 4.23) | 0.023 |
| Cuff 2 pure DGM lesions | 7 | 0.18 (2.15) | 9 | −0.88 (1.95) | 1.92 (0.17, 3.68) | 0.064 |
| Cuff 3 (outermost) pure DGM lesions | 7 | 0.14 (2.06) | 9 | −0.65 (1.87) | 1.63 (−0.13, 3.38) | 0.107 |
| Interaction test comparing treatment group differences between the components | 0.732 | |||||
| Lesion segments (defined by the baseline MTR of each voxel) | ||||||
| Quartile 1 (MTR‐defined) segment of pure WM lesions | 121 | 0.99 (2.65) | 69 | 0.52 (1.7) | 0.62 (−0.06, 1.31) | 0.080 |
| Quartile 2 (MTR‐defined) segment of pure WM lesions | 287 | 0.46 (2.55) | 163 | 0.26 (1.74) | 0.23 (−0.37, 0.83) | 0.462 |
| Quartile 3 (MTR‐defined) segment of pure WM lesions | 431 | 0.09 (2.13) | 265 | 0.10 (1.72) | 0.08 (−0.49, 0.66) | 0.776 |
| Quartile 4 (MTR‐defined) segment of pure WM lesions | 503 | −0.43 (1.93) | 306 | −0.45 (1.74) | 0.14 (−0.42, 0.71) | 0.622 |
| Interaction test comparing treatment group differences between the segments | 0.157 | |||||
| Quartile 1 (MTR‐defined) segment of pure CGM lesions | 32 | 1.61 (3.56) | 29 | 1.39 (3.21) | 0.98 (−0.63, 2.58) | 0.245 |
| Quartile 2 (MTR‐defined) segment of pure CGM lesions | 40 | 1.27 (3.18) | 32 | −0.07 (2.64) | 1.51 (−0.04, 3.06) | 0.070 |
| Quartile 3 (MTR‐defined) segment of pure CGM lesions | 42 | 0.44 (2.60) | 35 | −0.69 (3.01) | 1.40 (−0.13, 2.93) | 0.086 |
| Quartile 4 (MTR‐defined) segment of pure CGM lesions | 33 | −0.26 (2.81) | 27 | −1.29 (3.40) | 1.02 (−0.59, 2.62) | 0.227 |
| Interaction test comparing treatment group differences between the segments | 0.791 | |||||
| Quartile 1 (MTR‐defined) segment of pure DGM lesions | 5 | 1.83 (2.26) | 8 | −0.96 (2.07) | 2.66 (0.60, 4.72) | 0.050 |
| Quartile 2 (MTR‐defined) segment of pure DGM lesions | 6 | 0.22 (1.99) | 8 | −1.15 (1.83) | 2.09 (−0.01, 4.18) | 0.087 |
| Quartile 3 (MTR‐defined) segment of pure DGM lesions | 6 | −0.60 (1.60) | 8 | −1.40 (1.29) | 1.49 (−0.61, 3.59) | 0.202 |
| Quartile 4 (MTR‐defined) segment of pure DGM lesions | 5 | −1.19 (1.91) | 7 | −2.00 (1.76) | 2.24 (0.12, 4.37) | 0.072 |
| Interaction test comparing treatment group differences between the segments | 0.489 | |||||
| Lesion segments (defined by the baseline T1 value of each voxel) | ||||||
| Quartile 1 (T1‐defined) segment of pure WM lesions | 108 | −0.51 (2.32) | 79 | −0.32 (1.59) | 0.27 (−0.56, 1.11) | 0.525 |
| Quartile 2 (T1‐defined) segment of pure WM lesions | 197 | 0.08 (2.04) | 191 | 0 (1.72) | 0.09 (−0.62, 0.79) | 0.806 |
| Quartile 3 (T1‐defined) segment of pure WM lesions | 316 | 0.04 (2.29) | 121 | −0.05 (1.31) | −0.02 (−0.69, 0.65) | 0.957 |
| Quartile 4 (T1‐defined) segment of pure WM lesions | 261 | 0.08 (2.08) | 135 | −0.11 (2.13) | 0.35 (−0.32, 1.02) | 0.309 |
| Interaction test comparing treatment group differences between the segments | 0.447 | |||||
| Quartile 1 (T1‐defined) segment of pure CGM lesions | 20 | 0.56 (4.49) | 17 | 0.46 (2.51) | 0.57 (−1.64, 2.79) | 0.616 |
| Quartile 2 (T1‐defined) segment of pure CGM lesions | 31 | 0.09 (2.83) | 23 | 0.21 (3.63) | 1.29 (−0.78, 3.36) | 0.234 |
| Quartile 3 (T1‐defined) segment of pure CGM lesions | 36 | 0.19 (2.72) | 28 | −0.91 (3.83) | 1.66 (−0.35, 3.66) | 0.121 |
| Quartile 4 (T1‐defined) segment of pure CGM lesions | 26 | 0.17 (2.54) | 24 | −0.25 (3.51) | 2.01 (−0.07, 4.08) | 0.072 |
| Interaction test comparing treatment group differences between the segments | 0.544 | |||||
| Quartile 1 (T1‐defined) segment of pure DGM lesions | 2 | −0.41 (4.01) | 4 | −2.71 (1.3) | 2.90 (−0.23, 6.03) | 0.107 |
| Quartile 2 (T1‐defined) segment of pure DGM lesions | 4 | 1 (3.5) | 7 | −0.99 (1.7) | 2.17 (−0.49, 4.84) | 0.149 |
| Quartile 3 (T1‐defined) segment of pure DGM lesions | 5 | 0.34 (2.04) | 4 | 0.29 (2.23) | 1.19 (−1.62, 4.00) | 0.430 |
| Quartile 4 (T1‐defined) segment of pure DGM lesions | 3 | 0.16 (2.42) | 2 | −1.04 (2.02) | 3.00 (−0.50, 6.51) | 0.131 |
| Interaction test comparing treatment group differences between the segments | 0.545 | |||||
p values and 95% CIs are for the differences between bexarotene and placebo after adjustment (for the baseline value of that measure and the four binary minimisation factors). MTR, magnetisation transfer ratio; NA, not applicable.