Table 3.
Change in Magnetic Resonance Imaging Outcomes by Treatment Group and Stratified by Agea
| Outcome | Age, y | Change (SE) | Difference in change (95% CI) | P value for interaction | |
|---|---|---|---|---|---|
| Intensive treatment | Standard treatment | ||||
| Hippocampal volume, cm3 | <75 | −0.04 (0.01) | −0.02 (0.01) | −0.021 (−0.053 to 0.011) | .18 |
| ≥75 | −0.12 (0.02) | −0.05 (0.03) | −0.072 (−0.137 to −0.006) | ||
| Frontal gray matter volume, cm3 | <75 | −7.75 (0.35) | −6.73 (0.38) | −1.02 (−2.02 to −0.02) | .76 |
| ≥75 | −7.80 (0.67) | −6.43 (0.80) | −1.37 (−3.42 to 0.68) | ||
| SPARE-AD | <75 | 0.27 (0.03) | 0.24 (0.03) | 0.033 (−0.042 to 0.107) | .97 |
| ≥75 | 0.49 (0.05) | 0.45 (0.06) | 0.036 (−0.117 to 0.188) | ||
| Meta-ROI mean cortical thickness, mm | <75 | −0.10 (0.01) | −0.10 (0.01) | −0.002 (−0.031 to 0.026) | .91 |
| ≥75 | −0.11 (0.02) | −0.10 (0.02) | −0.006 (−0.063 to 0.052) | ||
| Mean FA in the cingulum bundle | <75 | −0.0004 (0.002) | 0.002 (0.002) | −0.003 (−0.008 to 0.002) | .58 |
| ≥75 | −0.006 (0.003) | −0.006 (0.004) | 0.0004 (−0.010 to 0.011) | ||
| Mean FA in the corpus callosum genu | <75 | −0.021 (0.003) | −0.017 (0.003) | −0.004 (−0.011 to 0.003) | .69 |
| ≥75 | −0.024 (0.005) | −0.023 (0.006) | −0.001 (−0.016 to 0.014) | ||
| CBF in the posterior cingulate gyrus, mL/100 mg/min | <75 | 0.03 (1.28) | −1.93 (1.36) | 1.96 (−1.70 to 5.63) | .41 |
| ≥75 | 0.13 (2.38) | 1.63 (2.88) | −1.50 (−8.84 to 5.85) | ||
| rCBF in the posterior cingulate gyrus relative to putamen | <75 | −0.10 (0.02) | −0.08 (0.03) | −0.021 (−0.090 to 0.047) | .64 |
| ≥75 | −0.07 (0.04) | −0.01 (0.05) | −0.058 (−0.195 to 0.079) | ||
| Frontal gray matter CBF, mL/100 mg/min | <75 | 1.49 (1.03) | −1.15 (1.08) | 2.64 (−0.27 to 5.56) | .40 |
| ≥75 | 0.57 (1.96) | 0.78 (2.28) | −0.21 (−6.12 to 5.70) | ||
Abbreviations: CBF, cerebral blood flow; FA, fractional anisotropy; rCBF, regional cerebral blood flow; ROI, region of interest; SPARE-AD, spatial pattern for recognition of Alzheimer disease.
Estimates based on a linear mixed model adjusting for sex, intracranial volume (for hippocampal volume, frontal gray matter volume, and SPARE-AD), and days since randomization, with random effects for participant and magnetic resonance imaging facility. Change denotes estimated least square mean comparing follow-up (estimated at 3.98 years postrandomization); negative values denote decreases from baseline, while positive values indicate increases from baseline. Difference in change reflects intensive treatment group minus standard treatment group.