Cognitive impairment and cortisol levels in first-episode schizophrenia patients.

Many modalities of cognition are affected in schizophrenia. The most common findings include dysfunctions of episodic and working memory and of executive functions. Although an inverse correlation between cortisol level and memory function has been proven, few studies have focused on the relationship between cortisol level and cognitive impairment in patients with schizophrenia. In an open, naturalistic, prospective study, consecutively hospitalized males diagnosed with first-episode schizophrenia, hypothalamic-pituitary-adrenal axis activity (afternoon cortisol levels, post-dexamethasone cortisol levels) was evaluated before and at the end of acute treatment. Psychopathology was assessed using the positive and negative syndrome scale (PANSS). Cognitive functions (memory, attention, psychomotor, verbal fluency, and executive functions) were tested after symptom alleviation using a neurocognitive test battery. In the total sample (n = 23), significant decreases in total PANSS score (including all subscales), afternoon cortisol levels, and post-dexamethasone cortisol levels occurred during the course of treatment. It was found that higher afternoon cortisol levels at the beginning of treatment were significantly related to impaired performance in memory functions. Afternoon cortisol levels were not significantly associated with other measured cognitive functions. No correlation was discovered between cognitive functions and post-dexamethasone cortisol levels. The determination of afternoon cortisol levels may serve to detect potential candidates for specific cognitive intervention immediately after the first psychotic breakthrough.