Korean Journal of Biological Psychiatry

Objectives：The aims of this study were to discriminate the clinical differences,to measure the estrogen and homovanillic acid levels, to evaluate a correlation between estrogen and homovanillic acid, and to identify an association of cognitivedeficit with estrogen and homovanillic acid among male and female schizophrenics.

Methods：In addition to the structured interviews, the plasma estrogen levels by radioimmunoassay and the homovanillic acid levels by HPLC were measured in 20 male and 21 female schizophrenics as well as 10 healthy male and 9 female controls.

Results：1) The plasma estrogen levels were higher in females than males, andsignificantly higher in female schizophenics than female controls. The homovanillicacid levels were higher in female schizophrenics than female controls, and werelower in male schizophrenics than male controls. 2) The onset age seemed to be earlier in male schizophrenics, and the frequencyof admission, duration of antipsychotic drug administration, dosage of antipsychoticsand duration of illnesses were more in males. The estrogen and homovanillic acid levels were significantly higher in female schizophrenics. 3) The estrogen levels had a significant positive correlation with sex, age and onset age, while the homovanillic acid levels did with sex. However, estrogen were notcorrelated with homovanillic acid levels. 4) The estrogen and homovanillic acid levels were not significantly different betweenmale and female schizophrenics with cognitive deficits. In the schizophrenic patients without cognitive deficits, the estrogen levels were significantly higher in females, while there were no significant sex differences in homovanillic acid.5) In the male and female schizophrenics predominantly with negative symptoms, there were no significant differences in estrogen and homovanillic acid levels. Inthose predominantly with positive symptoms, the estrogen levels were significantlyhigher in females, while there were no sex differences in homovanillic acid levels. 6) In schizophrenics with undifferentiated subtype, the estrogen and homovanillic acid levels were significantly higher in females. In those with paranoid or disorganized subtypes, the estrogen levels were significantly higher in females, while there were no sex differences in the homovanillic acid levels. 7) The mean values of PANSS-negative, PANSS-total, PANSS-CF, MMSE-K and estrogen levels were significantly higher in male schizophrenics with cognitivedeficits. The mean values of illness duration, CGI, PANSS-positive, PANSS-negative, PANSS-total, PANSS-CF and MMSE-K were significantly higher in femaleschizophrenics with cognitive deficits. 8) The variables which showed significant correlation with cognitive deficits werePANSS-negative, PANSS-total, PANSS-CF, MMSE-K and estrogen levels in male schizophrenics. The variables which showed significant correlation with cognitivedeficits were subtypes, onset age, illness durataion, CGI, PANSS-positive, PANSS-negative, PANSS-total, PANMSS-CF and MMSE-K in female schizophrenics.The estrogen levels were significantly correlated with admission frequencies, history of antipsychotic administration, duration of antipsychotic administration and cognitivedeficits in male schizophrenics, while age were not correlated with in females.The homovanillic acid levels had a significant correlation with subtypes and onset age in male schizophrenics, while there were no correlation among variables in females.

Conclusions：Although the plasma concentrations of estrogen and homovanillicacid in female schizophrenics were significantly higher than males, we could not find an association between them. Furtheremore, the various factors affecting on thecognitive deficits, estrogen and homovanillic acid levels seemed to be somewhat different according to sex.

Keywords Schizophrenia;Estrogen;Dopamine metabolites;Cognitive deficits;Positive symptoms;Undifferentiated type.