title: Increased ventricular lactate in chronic fatigue syndrome measured by 1H MRS imaging at 3.0 T. II: comparison with major depressive disorder.
abstract: Chronic fatigue syndrome (CFS), a complex illness characterized by fatigue, impaired concentration, and musculoskeletal pain, is often misdiagnosed as a psychiatric illness due to the overlap of its symptoms with mood and anxiety disorders. Using proton magnetic resonance spectroscopic imaging ((1)H MRSI), we previously measured levels of the major brain metabolites in CFS, in generalized anxiety disorder (GAD), and in healthy control subjects, and found significantly higher levels of ventricular cerebrospinal fluid (CSF) lactate in CFS compared to the other two groups. In the present study, we sought to assess the specificity of this observation for CFS by comparing ventricular lactate levels in a new cohort of 17 CFS subjects with those in 19 healthy volunteers and in 21 subjects with major depressive disorder (MDD), which, like GAD, is a neuropsychiatric disorder that has significant symptom overlap with CFS. Ventricular CSF lactate was significantly elevated in CFS compared to healthy volunteers, replicating the major result of our previous study. Ventricular lactate measures in MDD did not differ from those in either CFS or healthy volunteers. We found a significant correlation between ventricular CSF lactate and severity of mental fatigue that was specific to the CFS group. In an exploratory analysis, we did not find evidence for altered levels of the amino acid neurotransmitters, gamma-aminobutyric acid (GABA) and glutamate + glutamine ('Glx'), in CFS compared to MDD or healthy controls. Future (1)H MRS studies with larger sample sizes and well-characterized populations will be necessary to further clarify the sensitivity and specificity of neurometabolic abnormalities in CFS and MDD.
authors.affiliation: Department of Psychiatry, Mount Sinai School of Medicine, New York, NY, USA.
authors.forename: James W
authors.initials: JW
authors.lastname: Murrough
authors.forename: Xiangling
authors.initials: X
authors.lastname: Mao
authors.forename: Katherine A
authors.initials: KA
authors.lastname: Collins
authors.forename: Chris
authors.initials: C
authors.lastname: Kelly
authors.forename: Gizely
authors.initials: G
authors.lastname: Andrade
authors.forename: Paul
authors.initials: P
authors.lastname: Nestadt
authors.forename: Susan M
authors.initials: SM
authors.lastname: Levine
authors.forename: Sanjay J
authors.initials: SJ
authors.lastname: Mathew
authors.forename: Dikoma C
authors.initials: DC
authors.lastname: Shungu
mesh_terms: D000328:Adult; D002552:Cerebral Ventricles / Q000378:metabolism*; D003865:Major Depressive Disorder / Q000134:cerebrospinal fluid* / Q000503:physiopathology; D015673:Fatigue Syndrome, Chronic / Q000134:cerebrospinal fluid* / Q000503:physiopathology; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism; D006801:Humans; D019344:Lactic Acid / Q000134:cerebrospinal fluid*; D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation / Q000379:methods*; D008875:Middle Aged; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D019344:Lactic Acid; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid