Association between microbleed concentrations at t1 and MDz at t2
| Research Question | Region of Microbleed Concentration | White Matter Region of MD Measurement | Univariable | Multivariablea | ||
|---|---|---|---|---|---|---|
| Bcmb-conc (95% CI, P) | Bcmb-nr (95% CI) | Bcmb-conc (95% CI, P) | Bcmb-nr (95% CI) | |||
| 1.a | Cerebral hemispheres: | Cerebral hemispheres: | ||||
| Left | Left | 35.2 (8.6–61.8, .011) | 0.067 (0.016–0.117) | 38.4 (7.5–69.3, .017) | 0.073 (0.014–0.131) | |
| Right | Right | 28.3 (11.1–45.5, .002) | 0.055 (0.022–0.089) | 26.3 (5.7–47.0, .014) | 0.051 (0.011–0.091) | |
| 1.b | Central brain region | Central brain region | 8.2 (−8.5–24.9, .322) | 0.024 (−0.025–0.074) | 7.8 (−9.9–25.6, .374) | 0.023 (−0.029–0.076) |
| 2.a | Structures connected through the corpus callosum | Corpus callosum | 44.2 (23.6–64.8, .000) | 0.041 (0.022–0.060) | 20.0 (24.8–75.2, .000) | 0.019 (0.023–0.070) |
| 2.b | Cerebral hemispheres | Central brain region | 24.2 (6.8–41.5, .008) | 0.024 (0.007–0.040) | 25.7 (3.9–47.5, .023) | 0.025 (0.004–0.046) |
Note:–Results of linear regression analyses. None of the variables other than microbleed concentration is associated with MDz with P < .05 in the multivariable analyses.
↵a Multivariable linear regression analyses with the following independent variables: microbleed concentration, sex, age at the day of DTI imaging (years), and time passed from TBI to DTI acquisition (weeks). MDz indicates Z-score of mean diffusivity; t1, 3 (2–5) weeks after trauma; t2, 26 (25–28) weeks after trauma; Bcmb-conc, linear regression coefficient with microbleed-concentration as independent variable; Bcmb-nr, linear regression coefficient with number of microbleeds as independent variable.