A Marked Low-Grade Inflammation and a Significant Deterioration in Metabolic Status in First-Episode Schizophrenia: A Five-Year Follow-Up Study

Peripheral Lipid Signatures, Metabolic Dysfunction, and Pathophysiology in Schizophrenia Spectrum Disorders

Metabolic dysfunction is commonly observed in schizophrenia spectrum disorders (SSDs). The causes of metabolic comorbidity in SSDs are complex and include intrinsic or biological factors linked to the disorder, which are compounded by antipsychotic (AP) medications. The exact mechanisms underlying SSD pathophysiology and AP-induced metabolic dysfunction are unknown, but dysregulated lipid metabolism may play a role. Lipidomics, which detects lipid metabolites in a biological sample, represents an analytical tool to examine lipid metabolism. This systematic review aims to determine peripheral lipid signatures that are dysregulated among individuals with SSDs (1) with minimal exposure to APs and (2) during AP treatment. To accomplish this goal, we searched MEDLINE, Embase, and PsychINFO databases in February 2024 to identify all full-text articles written in English where the authors conducted lipidomics in SSDs. Lipid signatures reported to significantly differ in SSDs compared to controls or in relation to AP treatment and the direction of dysregulation were extracted as outcomes. We identified 46 studies that met our inclusion criteria. Most of the lipid metabolites that significantly differed in minimally AP-treated patients vs. controls comprised glycerophospholipids, which were mostly downregulated. In the AP-treated group vs. controls, the significantly different metabolites were primarily fatty acyls, which were dysregulated in conflicting directions between studies. In the pre-to-post AP-treated patients, the most impacted metabolites were glycerophospholipids and fatty acyls, which were found to be primarily upregulated and conflicting, respectively. These lipid metabolites may contribute to SSD pathophysiology and metabolic dysfunction through various mechanisms, including the modulation of inflammation, cellular membrane permeability, and metabolic signaling pathways.

Intestinal permeability and low-grade chronic inflammation in schizophrenia: A multicentre study on biomarkers. Rationale, objectives, protocol and preliminary results

BACKGROUND

Altered intestinal permeability and low-grade chronic inflammation disrupt the integrity of the blood-brain barrier (microbiota-gut-brain axis), probably playing a role in the pathophysiology of schizophrenia-spectrum disorders. However, studies assessing the microbiota-gut-brain axis are inconsistent. This article describes the rationale, objectives, protocol, and presents descriptive results for a new project.

METHODS

The sample of this study came from an observational, cross-sectional and multisite study including four centers in Spain (PI17/00246) recruiting adult patients with DSM-5 schizophrenia-spectrum disorders at any stage of the disease. The aims of the project are to assess the interrelation between intestinal permeability and low-grade chronic inflammation in schizophrenia-spectrum disorders and the role of peripheral biomarkers, diet, exercise, metabolic syndrome, disease severity and functioning as well as cognition. Assessments included the following variables: (1) anthropometric, (2) intestinal permeability, diet, and physical exercise, (3) clinical and functional, (4) neuropsychological and cognitive reserve, and (5) peripheral biomarkers from blood.

RESULTS

A total of 646 patients were enrolled (257, 39.7% female). Mean age was 43.2±13.6 years, illness duration 15.1±11.5 years. 55.8% consumed tobacco. Positive PANSS score was 13.68±6.55, and 20.38±8.69 in the negative symptoms. CGI was 4.16±2.22 and GAF was 60.00±14.84.

CONCLUSION

The results obtained by this project are expected to contribute toward the understanding of the physiopathology of schizophrenia-spectrum disorders. This will likely aid to personalize treatments in real-world clinical practice, potentially including variables related to intestinal permeability and inflammation.

Kynurenine pathway dynamics in patients with schizophrenia spectrum disorders across the disease trajectory

The aim of this study was to evaluate how schizophrenia spectrum disorders (SSD) and applied long-term (5.1 years) antipsychotic (AP) treatment affect the serum levels of tryptophan (Trp) metabolites. A total of 112 adults (54 first-episode psychosis [FEP] patients and 58 control subjects [CSs]) participated in the study. The investigated changes in the metabolite levels appeared against a background of persistent increase in BMI and waist circumference among the patients. Regarding the kynurenine (KYN) pathway, the strongest changes were seen in AP-naïve FEP patients. Trp, KYN, kynurenic acid (KYNA), and anthranilic acid (ANT) levels were significantly reduced in blood samples from patients in the early stage of the disease. Furthermore, 3-OH-kynurenine (3-HK) and quinolinic acid (QUIN) levels were somewhat lower in these patients. Most of these changes in the KYN pathway became weaker with AP treatment. The levels of serotonin and its metabolite 5-HIAA tended to be higher at 5.1 years in patients showing the relation of elevated serotonin turnover to increased BMI and waist circumference. The similar trend was evident for the ratio between xanthurenic acid (XA) and KYNA with strong link to the elevated BMI. Altogether, the present study supports the role of Trp-metabolites in the development of obesity and metabolic syndrome in SSD patients.

"Severe Anemia: A Case Report of an Uncommon Precipitant of Schizophrenia Relapse"

A 48-year-old patient with stable residual schizophrenia experienced a syndromic psychosis relapse following an episode of severe combined immunohemolytic and pure red cell aplastic anemia, with a hemoglobin level of 4.7 g/dl. The anemia was attributed to her anti-HIV medication zidovudine. Her HIV infection had been well-controlled; no other organic precipitant of the psychosis was found. Following transfusion of 2 units of leukocyte-poor packed red cells, schizophrenia symptoms promptly recovered to her baseline. This was maintained at 3- and 6-month follow-ups without any need for antipsychotic dose adjustment. Following zidovudine discontinuation and a short course of oral prednisolone, her anemia gradually recovered.