Table 3.

Relationships between suicidal ideation and ¹H-MRS-measured anterior cingulate metabolites.

Metabolite	b̂	SE	95% CI for b̂	p (pFDR)
	Severity of ideation
Glu	2.486	1.644	−0.863 to 5.834	0.140 (0.187)
Glx	5.653	2.518	0.518 to 10.788	0.032 (0.064)
NAA	−0.262	0.936	−2.168 to 1.644	0.781 (0.781)
NAA/Glx	−0.044	0.014	−0.072 to −0.016	0.003 (0.012)
	Intensity of ideation
Glu	0.655	0.403	−0.167 to 1.476	0.114 (0.152)
Glx	1.603	0.607	0.365 to 2.841	0.013 (0.026)
NAA	−0.014	0.231	−0.484 to 0.457	0.952 (0.952)
NAA/Glx	−0.012	0.003	−0.018 to −0.005	0.001 (0.004)

Multiple linear regressions examining relationships of suicidal ideation severity and intensity with ¹H-MRS-measured ACC metabolites. Regression models include sex, age at scan, psychotropic medication use, and depression severity (adjusted CDRS-R total score). The unstandardized parameter estimate (coefficient) for the SI variable (b̂), standard error of b̂, 95% confidence intervals for b̂, and p-values for the regression relationship between the suicidal ideation variable and the ACC metabolite are reported.

¹H-MRS proton magnetic resonance spectroscopy, CI confidence interval, Glu glutamate, Glx glutamate+glutamine, NAA N-acetylaspartate, p_FDR p-value adjusted for multiple comparisons according to the false-discovery rate procedure⁵⁹, SE standard error.