There are systematic differences in clinical features between women and men with schizophrenia (SCZ). The regulation of sex hormones may play a potential role in abnormal neurodevelopment in SCZ. Brain-derived neurotrophic factor (BDNF) and sex hormones have complex interacting actions that contribute to the etiology of SCZ.

To investigate the influence of BDNF and sex hormones on cognition and clinical symptomatology in chronic antipsychotic-treated male SCZ patients.

The serum levels of follicle-stimulating hormone, luteinizing hormone (LH), estradiol (E2), progesterone, testosterone (T), prolactin (PRL) and BDNF were compared between chronic antipsychotic-treated male (CATM) patients with SCZ (n = 120) and healthy controls (n = 120). The Positive and Negative Syndrome Scale was used to quantify SCZ symptoms, while neuropsychological tests were used to assess cognition. Neuropsychological tests, such as the Digit Cancellation Test (DCT), Semantic Verbal Fluency (SVF), Spatial Span Test (SS), Paced Auditory Serial Addition Test (PASAT), Trail Making Task (TMT-A), and Block Design Test (BDT), were used to assess executive functions (BDT), attention (DCT, TMT-A), memory (SS, PASAT), and verbal proficiency (SVF).

Although E2 levels were significantly lower in the patient group compared to the healthy controls, T, PRL, and LH levels were all significantly higher. Additionally, the analysis revealed that across the entire sample, there were positive correlations between E2 Levels and BDNF levels as well as BDNF levels and the digital cancellation time. In CATM patients with SCZ, a significant correlation between the negative symptoms score and PRL levels was observed.

Sex hormones and BDNF levels may also be linked to cognitive function in patients with chronic SCZ.

There is a discrepancy in literature regarding level of prolactin in drug free/ drug naïve patients with non-affective psychosis. Few earlier studies have found low levels of prolactin whereas recent studies have found high levels of prolactin when compared to controls. Most of these studies have not considered the possible confounding factors. Also ours is the first study that evaluated the correlation between psychopathology & prolactin levels after considering the confounding agents.

It was a cross sectional, hospital based case control study. Purposive sampling was done to identify the cases of schizophrenia. 59 cases and 59 controls fulfilling inclusion and exclusion criteria were taken for the study after taking consent. Socio-demographic and other relevant clinical data were collected. Scores of PANSS AND BPRS were collected on the day of admission. Blood samples were collected from 8 to 10 am in the morning. Samples were centrifuged and the serum was stored in sterile vials at minus 80° centigrade. Serum Prolactin, free T3, freeT4, Thyroid Stimulating Hormone & Cortisol levels were evaluated for both cases and controls and correlation between them and with psychopathology of cases was seen.

Our study showed that prolactin level was increased in drug free/naïve cases of schizophrenia. Significant difference was found between T4 levels of cases and controls. No correlation was found between prolactin and psychopathology.

Prolactin is increased in drug free/ drug naïve patients of schizophrenia and this is not related to confounding factors. There was no significant correlation between prolactin and psychopathology.

Increased levels of high-sensitivity C reactive protein (hsCRP) have been reported in schizophrenia, but to date, no study is designed to examine serum hsCRP in acutely agitated patients with schizophrenia, an extreme state that requires immediate diagnosis and medical treatment. Serum hsCRP levels were assessed in 32 clinically acutely agitated patients and 42 healthy control subjects matched for demographic properties. Further, serum hsCRP levels in acutely agitated patients were compared with control subjects and with the levels after the patients were treated with anti-psychiatric medications. Meanwhile, the influence of clinical subtypes, family history, and gender, as well as the levels of white blood cell (WBC) counts were also considered. In results, serum hsCRP levels were significantly higher in acutely agitated patients with schizophrenia than in healthy subjects. The elevation of serum hsCRP in patients was not affected by gender, family history (P>0.05), and clinical classification of schizophrenia (P>0.05). However, the elevation of hsCRP was suppressed by the medical treatment for schizophrenia with acute agitation (P<0.05). In addition, WBC counts, another inflammation-related indicator, were also increased significantly in acutely agitated patients compared with healthy subjects, consistent with the elevation of serum hsCRP. In conclusion, hsCRP is an important indicator of immune alterations in the pathogenesis of schizophrenia and has potential to be developed into a sensitive marker for the acute agitation in schizophrenia.

Secretion of the anterior pituitary hormone prolactin can be significantly increased by antipsychotic drugs, leading to a range of adverse effects in patients with schizophrenia. However, there is evidence from a variety of studies that prolactin may also be related to symptom profile and treatment response in these patients, and recent work has identified variations in prolactin secretion even in drug-free patients. In this paper, a selective review of all relevant studies pertaining to prolactin and schizophrenia, including challenge and provocation studies, is presented. The implications of this work are discussed critically. A tentative model, which synthesizes these findings and argues for a significant role for prolactin in the development of schizophrenia, is outlined.

This chapter has carried out a review of the literature and combined this with the results of in-house studies to identify candidate blood-based biomarkers for schizophrenia and antipsychotic drug response. Literature searches retrieved 185 publications describing a total of 273 schizophrenia biomarkers identified in serum and/or plasma. Examination of seven in-house multicenter studies resulted in the identification of 137 serum/plasma biomarkers. Taken together, the findings suggested an ongoing immunological and inflammatory process in schizophrenia. This was accompanied by altered cortisol levels which suggested activated stress response and altered hypothalamic-pituitary-adrenal axis function in these patients. The authors conclude that such biomarkers may prove useful as additional parameters for characterizing specific immune and/or metabolic or hormonal subsystems in schizophrenia and might, therefore, facilitate the development of future patient stratification and personalized medicine strategies.