Table 2.
Volumetric and Diffusion Imaging Measurements
| Volumetric Measures | |||||
|---|---|---|---|---|---|
| Imaging Measure | HIV-Infected | HIV-Uninfected | Difference (95% CI) |
t206 | P Value |
| Gray matter volume, mL | 659 | 673 | 13.7 (2.3–25.1) | 2.37 | .02 |
| White matter volume, mL | 479 | 476 | 2.4 (–6.4 to 11.2) | –0.54 | .59 |
| Diffusion Measures | |||||
| Imaging Measure | HIV-Infected | HIV-Uninfected | Difference (95% CI) |
t202 | P Value |
| Fractional anisotropy | 0.477 | 0.484 | 0.007 (.002–.012) | 2.92 | <.01 |
| Mean diffusivity, mm2/s | 705 | 696 | 8.5 (1.2–15.8) | –2.27 | .02 |
| Radial diffusivity, mm2/s | 503 | 493 | 10.3 (2.7–17.9) | –2.66 | <.01 |
| Axial diffusivity, mm2/s | 1108 | 1103 | 4.9 (–2.5 to 12.3) | –1.31 | .19 |
Least squares means, a potentially better estimate of the true population mean for each neuroimaging measure by HIV status and 95% CIs, adjusted for age, intracranial volume, and scanner type. Subscript indicates degrees of freedom for the t-statistic.
Abbreviations: CI, confidence interval; HIV, human immunodeficiency virus.