An Exploratory Study of Inflammatory Biomarkers and Extrapyramidal Side Effects in Patients with Schizophrenia.

Background: Extrapyramidal symptoms (EPS) are common side effects of antipsychotic medications and can contribute to medication non-adherence and subsequent relapse in schizophrenia. Recent research suggests that inflammatory markers, such as the neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), monocyte-lymphocyte ratio (MLR), and systemic immune-inflammation index (SII), may serve as biomarkers for treatment response in schizophrenia. This exploratory study is a first look at the relationship between these inflammatory markers and EPS in patients with schizophrenia. Study Design: Fifty patients with schizophrenia spectrum disorders were recruited, with 28 completing bloodwork. EPS was assessed using the Extrapyramidal Symptom Rating Scale (ESRS), and overall side effects were evaluated using the Glasgow Antipsychotic Side-Effect Scale (GASS). Blood samples were analyzed to calculate NLR, PLR, MLR, and SII. Study Results: Monocyte count was negatively correlated with the ESRS akathisia subscale. Higher SII scores were significantly associated with self-reported parkinsonism and hyperkinesia. Patients on clozapine had significantly higher PLR and MLR compared to those on other antipsychotics. No significant association was found between total GASS scores and inflammatory markers. Conclusions: These findings suggest that certain inflammatory markers may be associated with specific EPS subscales. Further research with larger samples is needed to validate these results.