166. HAEMATOLOGICAL AND INFLAMMATORY MARKERS ASSOCIATED WITH NON-REMISSION AND TREATMENT RESISTANCE IN SCHIZOPHRENIA

Le résumé fourni par la source

Abstract Background Changes in haematological parameters and inflammatory markers including the neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR) and monocyte/lymphocyte ratio (MLR) have been observed in schizophrenia, but few studies have investigated both in relation to symptom remission and treatment resistance. Clozapine use may also affect these parameters, but data in literature beyond the first two years post-initiation is limited. Aims & Objectives We aimed to investigate haematological and inflammatory changes associated with non-remission in schizophrenia, and identify if changes were associated with treatment resistance or long-term clozapine use. Method Healthy individuals and patients diagnosed with schizophrenia were recruited between 2016 to 2022 from the community, and from outpatient and inpatient settings. Data including age, sex, ethnicity, medical comorbidities and medication prescriptions were collected. Full blood count investigations were performed on recruitment. Patients were assessed on the Positive and Negative Syndrome Scale, and categorised into symptom remitters versus non-remitters based on the Andreason remission criteria. They were further categorized into antipsychotic-responsive (ARS), clozapine-responsive (nCR-TRS) and clozapine-resistant treatment-resistant schizophrenia (CR-TRS) groups, based on remission status and clozapine use as a proxy for treatment resistance. Individuals with autoimmune conditions and smokers were excluded to yield a sample of 232 individuals. We investigated differences in 20 full blood count parameters, NLR, PLR and MLR. Three main analyses were performed: a 2-group analysis comparing healthy individuals against patients with schizophrenia, a 3-group analysis comparing healthy individuals, symptom remitters versus non-remitters, and a 4-group analysis comparing healthy individuals, ARS, nCR-TRS and CR-TRS. Among patients, we further compared clozapine users versus non-users. Results In the 2-group comparison, red blood cell counts (p = 0.009), absolute neutrophil count (p = 0.028), neutrophils percentage (p = 0.005) and basophils percentage (p = 0.018) were significantly lower in schizophrenia. Absolute lymphocyte count (p = 0.032), lymphocytes percentage (p = 0.004), NLR (p = 0.004) and MLR (p = 0.009) were higher in schizophrenia. In the 3-group comparison, neutrophils percentage (p = 0.017), NLR (p = 0.015) and MLR (p = 0.021) showed an increasing trend from healthy controls to remitters then non-remitters, while lymphocytes percentage (p = 0.009), platelet count (p = 0.034) and red blood cell counts (p <0.001) showed a decreasing trend. Similar trends were seen in the 4-group comparison with increasing treatment resistance — most significant differences were seen between healthy controls and nCR-TRS or TRS groups. Most parameters were not significantly different between clozapine users versus non-users, and instead higher mean platelet volume (p = 0.006) and monocytes percentage (p = 0.027) were uniquely observed among clozapine users. Mean duration of clozapine use was 7 years. Discussion & Conclusions Most haematological and inflammatory changes appear to be related to disease burden rather than clozapine use. We found higher NLR and MLR, lower red blood cell counts and lower platelet counts in schizophrenia, with non-remission and increasing treatment resistance. Raised NLR and MLR suggest ongoing inflammation in active psychosis and may be viable biomarkers of active disease and treatment resistance. Further studies are required to clarify if other haematological changes are related to underlying disease or associated processes.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.