. Author manuscript; available in PMC: 2015 Aug 1.

Published in final edited form as: Ann Neurol. 2014 Jul 9;76(2):269–278. doi: 10.1002/ana.24202

TABLE 3.

Glutamate and Sustained Elevation of Glutamate as Predictors of NAA Decline (N₁ = 343 and N₂ = 211, respectively)

	Outcome
Predictor	NAA[_NAWM]	NAA_[GM]
Glu_[NAWM]	–0.03 (–0.07 to 0.01) p = 0.12	–0.06 (–0.11 to –0.02) p = 0.004^a
Glu_[GM]	–0.03 (–0.07 to –0.002) p = 0.038^a	–0.05 (–0.08 to –0.02) p = 0.003^a
Sustained elevation Glu_[NAWM]	–0.28 (–0.41 to –0.15) p < 0.001^a	–0.15 (–0.30 to 0.004) p = 0.056^a
Sustained elevation Glu_[GM]	0.21 (–0.14 to 0.56) p = 0.24	–0.07 (–0.46 to 0.33) p = 0.75

Parameter estimate for the predictor by time interaction and 95% confidence intervals are given for each model.

Mean follow-up time was 2.2 years for NAA.

Models in which the predictor by time interaction was statistically significant at α = 0.05.

Glu = glutamate; GM = gray matter; NAA = N-acetylaspartate; NAWM = normal-appearing white matter.