Correlation of individual symptoms and other clinical variables with cerebrospinal fluid amine metabolites and tryptophan in depression.

Cerebrospinal fluid 5-hydroxyindoleacetic acid (5HIAA), homovanillic acid (HVA), and tryptophan in both CSF and plasma were measured in a carefully selected group of 33 depressed women. Strict and explicit inclusion and exclusion criteria were used, and CSF was taken under controlled circumstances. Seventeen operationally defined and uniformly rate psychiatric symptoms as well as global depression severity and 12 clinical background variables were correlated with the four biochemical parameters, using multivariate regression analysis based on Spearman's rank correlation coefficient according to the nature of the data. Global depression severity did not correlated with any of the biochemical variables; there were, however, significant correlations between CSF 5HIAA and anxiety, insomnia, and suicide on the one hand, and between CSF HVA and motor symptoms and paranoidity on the other hand. Background variables showed only a few--and much weaker--correlations. It was concluded that central monoamine metabolism does affect some particular psychiatric symptoms but is not parallel with the complex clinical construct of the depressive disease. Further studies using isolated psychopathological symptoms instead of nosological categories are suggested in clinical neurochemistry.