Skip to main content

Table 1 Comparison of plasma amino acids levels and nitric oxide levels in the 9 symptoms of major depressive disorder according to the DSM-IV

From: Decreased plasma neuroactive amino acids and increased nitric oxide levels in melancholic major depressive disorder

Symptom items Subgrouping Asp Glu Gly GABA NO
Item 1: depressed mood No: n = 0
Yes: n = 27
Item 2: diminished interest No: n = 3 0.643 0.841 0.700 0.076 0.817
Yes: n = 24
Item 3: weight loss No: n = 13 0.382 0.898 0.438 0.645 0.382
Weight gain: n = 0
Weight loss: n = 14
Item 4: disordered psychomotor state No change: n = 4 0.417 0.450 0.883 0.985 0.346
Agitation: n = 10
Retardation: n = 13
Item 5: disordered sleep No: n = 1 0.847 0.616 0.773 0.312 0.211
Hypersomnia: n = 2
Insomnia: n = 24
Item 6: fatigue or loss of energy No: n = 9 0.382 0.647 0.643 0.396 0.607
Yes: n = 18
Item 7: feeling of worthlessness or guilt No: n = 11 0.374 0.775 0.402 0.711 0.693
Yes: n = 16
Item 8: diminished ability to think or concentrate, or indecisiveness No: n = 9 0.837 0.617 0.719 0.662 0.090
Yes: n = 18
Item 9: thought of death or suicide No: n = 12 0.118 0.504 0.495 0.054 0.558
Yes: n = 15
  1. Notes: Comparison of plasma levels of the 4 amino acids or NO levels among different sub-phenotype groups, based upon the 9 symptoms of major depressive disorder according to the DSM-IV. No: without this symptom; Yes: with this symptom. The numbers in the Table are P values. Comparison among 3 subgroups was performed by Kruskal -Wallis H test. Comparison between 2 subgroups was performed by Mann-Whitney U test. Asp: aspartic acid; Glu: glutamic acid; Gly: glycine; GABA: gamma-aminobutyric acid; NO: nitric oxide. The 9 symptoms includes: 1. depressed mood most of the day, nearly every day, as indicated by either subjective report (e.g. feels sad or empty) or observation made by others (e.g. appears tearful); 2. markedly diminished interest or pleasure in all, or almost all, activities most of the day, nearly every day (as indicated by either subjects account or observation made by others); 3. significant weight loss when not dieting or weight gain (e.g. a change of more than 5% of body weight in a month), or decrease or increase in appetite nearly every day; 4. psychomotor agitation or retardation nearly every day (observable by others, not merely subjective feelings of restless or being showed down); 5. insomnia or hypersomnia nearly every day; 6. fatigue or loss of energy nearly every day; 7. feelings of worthlessness or excessive or inappropriate guilt (which may be delusional) near every day (not merely self-reproach or guilt about being sick); 8. diminished ability to think or concentrate, or indecisiveness, nearly every day (either by subjective account or as observed by others); 9. recurrent thoughts of death (not just fear of dying), recurrent suicidal ideation without a specific plan, or a suicide attempt or a specific plan for committing suicide.