Effects of hormones on cognition in schizophrenic male patients--preliminary results

Schizophrenia is a prevalent neurodevelopmental disorder of an unknown etiology and a variable phenotypic expression. In the recent years, the impact of hormones on the course of schizophrenia has been investigated. This study is aimed at assessing the level of correlating serum levels of hormones in schizophrenic male patients with their cognitive functioning measured with neuropsychological tests.

In the index group there were 15 medicated male schizophrenic patients. In the control group there were 15 age and education matched healthy men. All subjects underwent analysis of serum hormones level (TSH, testosterone, estradiol, FSH, LH, progesterone and prolactin) and a battery of tests (Trail Making Test A and B, Stroop Test, Verbal and Semantic Fluency Test).

The mean serum levels of the following hormones were higher in the index group than in the control group: TSH (1.76 mIU/L vs 1.58 mIU/L; p=0.66), progesterone (0.85 ng/ml vs 0.69 ng/ml; p=0.22) and prolactin (558.71 uIU/ml vs 181 uIU/ml; p=0.025). The mean levels of estradiol (24.36 pg/ml vs 25.40 ng/ml; p=0.64), FSH (3.17 mIU/ml vs 5.72 mIU/ml; p=0.019), LH (3.85 mIU/ml vs 5.77 mIU/ml; p=0.056) and testosterone (2.90 ng/ml vs 5.38 ng/ml; p=0.003) were higher in the control group. In the index group there were significant negative correlations between FSH and semantic fluency (ρ=-0.678606), progesterone and: TMT B (ρ=-0.586763), Stroop 1 (ρ=-0.701880) and Stroop 2 (ρ=-0.601074) and prolactin and TMT A (ρ=-0.579607).

The preliminary results of our study show that serum levels of FSH and testosterone are significantly lower, whereas the level of prolactin is markedly higher, in schizophrenic male patients than in healthy men. There is an inverse correlation between serum levels of progesterone, FSH and prolactin and the results of certain cognitive functioning tests in schizophrenic men.