Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland.
JAMA Psychiatry. 2019 Mar 1;76(3):314-323. doi: 10.1001/jamapsychiatry.2018.3637.
The use of high-field magnetic resonance spectroscopy (MRS) in multiple brain regions of a large population of human participants facilitates in vivo study of localized or diffusely altered brain metabolites in patients with first-episode psychosis (FEP) compared to healthy participants.
To compare metabolite levels in 5 brain regions between patients with FEP (evaluated within 2 years of onset) and healthy controls, and to explore possible associations between targeted metabolite levels and neuropsychological test performance.
DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional design used 7-T MRS at a research MR imaging facility in participants recruited from clinics at the Johns Hopkins Schizophrenia Center and the local population. Eighty-one patients who had received a DSM-IV diagnosis of FEP within the last 2 years and 91 healthy age-matched (but not sex-matched) volunteers participated.
Brain metabolite levels including glutamate, glutamine, γ-aminobutyric acid (GABA), N-acetylaspartate, N-acetylaspartyl glutamate, and glutathione, as well as performance on neuropsychological tests.
The mean (SD) age of 81 patients with FEP was 22.3 (4.4) years and 57 were male, while the mean (SD) age of 91 healthy participants was 23.3 (3.9) years and 42 were male. Compared with healthy participants, patients with FEP had lower levels of glutamate (F1,162 = 8.63, P = .02), N-acetylaspartate (F1,161 = 5.93, P = .03), GABA (F1,163 = 6.38, P = .03), and glutathione (F1,162 = 4.79, P = .04) in the anterior cingulate (all P values are corrected for multiple comparisons); lower levels of N-acetylaspartate in the orbitofrontal region (F1,136 = 7.23, P = .05) and thalamus (F1,133 = 6.78, P = .03); and lower levels of glutathione in the thalamus (F1,135 = 7.57, P = .03). Among patients with FEP, N-acetylaspartate levels in the centrum semiovale white matter were significantly correlated with performance on neuropsychological tests, including processing speed (r = 0.48; P < .001), visual (r = 0.33; P = .04) and working (r = 0.38; P = .01) memory, and overall cognitive performance (r = 0.38; P = .01).
Seven-tesla MRS offers insights into biochemical changes associated with FEP and may be a useful tool for probing brain metabolism that ranges from neurotransmission to stress-associated pathways in participants with psychosis.
与健康对照相比，使用高磁场磁共振波谱（MRS）对首发精神病（FEP）患者的多个大脑区域进行研究，可以在体内研究局部或弥散性改变的脑代谢物。
比较 FEP 患者（发病后 2 年内评估）和健康对照者 5 个脑区的代谢物水平，并探讨靶向代谢物水平与神经心理学测试表现之间的可能关联。
设计、地点和参与者：在约翰霍普金斯精神分裂症中心和当地人群的诊所招募参与者，在研究磁共振成像设施中使用 7T MRS 进行横断面设计。81 名 FEP 患者在过去 2 年内接受了 DSM-IV 诊断，91 名健康年龄匹配（但性别不匹配）志愿者参加了研究。
脑代谢物水平，包括谷氨酸、谷氨酰胺、γ-氨基丁酸（GABA）、N-乙酰天冬氨酸、N-乙酰天冬氨酸谷氨酸和谷胱甘肽，以及神经心理学测试表现。
81 名 FEP 患者的平均（标准差）年龄为 22.3（4.4）岁，57 名为男性，91 名健康参与者的平均（标准差）年龄为 23.3（3.9）岁，42 名为男性。与健康参与者相比，FEP 患者的前扣带回谷氨酸（F1,162=8.63，P=0.02）、N-乙酰天冬氨酸（F1,161=5.93，P=0.03）、GABA（F1,163=6.38，P=0.03）和谷胱甘肽（F1,162=4.79，P=0.04）水平较低（所有 P 值均经多重比较校正）；眶额区域（F1,136=7.23，P=0.05）和丘脑（F1,133=6.78，P=0.03）的 N-乙酰天冬氨酸水平较低；丘脑（F1,135=7.57，P=0.03）的谷胱甘肽水平较低。在 FEP 患者中，半卵圆中心白质的 N-乙酰天冬氨酸水平与神经心理学测试表现显著相关，包括加工速度（r=0.48；P<0.001）、视觉（r=0.33；P=0.04）和工作（r=0.38；P=0.01）记忆以及整体认知表现（r=0.38；P=0.01）。
7T MRS 提供了与 FEP 相关的生化变化的见解，并且可能是研究参与者精神病中从神经传递到与应激相关的途径的脑代谢的有用工具。
