Variations in CSF monoamine metabolites according to the season of birth

The cerebrospinal fluid (CSF) concentrations of the monoamine metabolites 5 -hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA) and 3-methoxy-4 -hydroxyphenylglycol (MHPG) as well as their ratios and correlations were a nalyzed in relation to the season of birth. The sample consisted of 241 dru g-free patients participating in psychobiological programs and comprising t he DSM-III-R diagnoses of mood, anxiety and adjustment disorders. Significa nt season-of-birth variations were found even after adjusting for sex, age, height, the diagnostic category and the month of lumbar puncture. Those bo rn during February to April had significantly lower values of 5-HIAA. Value s of HVA and of the ratios HVA/5-HIAA and HVA/MHPG were significantly highe r for those born during October to January. Correlation coefficients also s howed season-of-birth variations. These results may provide an important li nk for the season-of-birth variations reported for several neuropsychiatric disorders.