Iron status in schizophrenic patients with acute neuroleptic-induced dystonic reactions

Beyond the Mind-Serum Trace Element Levels in Schizophrenic Patients: A Systematic Review

The alterations in serum trace element levels are common phenomena observed in patients with different psychiatric conditions such as schizophrenia, autism spectrum disorder, or major depressive disorder. The fluctuations in the trace element concentrations might act as potential diagnostic and prognostic biomarkers of many psychiatric and neurological disorders. This paper aimed to assess the alterations in serum trace element concentrations in patients with a diagnosed schizophrenia. The authors made a systematic review, extracting papers from the PubMed, Web of Science, and Scopus databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Among 5009 articles identified through database searching, 59 of them were assessed for eligibility. Ultimately, 33 articles were included in the qualitative synthesis. This review includes the analysis of serum levels of the following trace elements: iron, nickel, molybdenum, phosphorus, lead, chromium, antimony, uranium, magnesium, aluminum, zinc, copper, selenium, calcium, and manganese. Currently, there is no consistency regarding serum trace element levels in schizophrenic patients. Thus, it cannot be considered as a reliable prognostic or diagnostic marker of schizophrenia. However, it can be assumed that altered concentrations of those elements are crucial regarding the onset and exaggeration of either psychotic or negative symptoms or cognitive dysfunctions.

Iron homeostasis alterations and risk for akathisia in patients treated with antipsychotics: A systematic review and meta-analysis of cross-sectional studies

Iron homeostasis may be implicated in the pathophysiology of antipsychotic-related akathisia. We performed a systematic review in six databases from database inception until 03/2020, conducting a meta-analysis of studies investigating iron metabolism in antipsychotic-treated patients with versus without akathisia. Using a fixed- and a random-effects model, standardized mean difference (SMD) was estimated for levels of iron, ferritin, transferrin and total iron-binding capacity. Meta-regression analyses included sex, age, illness duration and antipsychotic treatment and dose. Subgroup analyses included chronic vs. acute akathisia and different diagnoses. Study quality was assessed using the Newcastle-Ottawa scale. In 10 studies (n = 395), compared to non-akathisia patients (n = 213), iron levels were lower in patients with akathisia (n = 182; fixed-effect model: SMD=-0.49, 95%CI=-0.28,-0.70, p<0.001; random-effects model: SMD=-0.55, 95%CI=-0.14,-0.96, p = 0.008). For secondary outcomes, differences were significant regarding lower ferritin levels in patients with akathisia in the fixed-effect model (SMD=-0.32, 95%CI=-0.08,-0.55, p = 0.007), but not in the random-effects model (SMD=-0.29, 95%CI=0.20,-0.79, p = 0.24). None of the moderators/mediators had a significant effect on the group difference of iron levels. Subgroup analyses reported lower iron levels in both patients with chronic and acute akathisia vs. patients without. Iron levels for schizophrenia patients were lower in the fixed-effect model (SMD=-0.55, 95%CI=-0.23, -0.86, p<0.001), while a trend was observed in the random-effects model (SMD=-0.52, 95%CI=-0.07, -1.12, p = 0.08). The studies' quality was overall poor, with one exception. This meta-analysis suggests lower iron levels in akathisia patients, while ferritin differences were significant only in the fixed-effect model. Further data are required to promote the understanding of related pathways.

Trace elements in schizophrenia: a systematic review and meta-analysis of 39 studies (N = 5151 participants)

Context

The pathogenesis of schizophrenia appears to be multifaceted.

Objective

The aim of this meta-analysis of studies that investigated blood and hair concentrations of trace elements in people diagnosed with schizophrenia was to determine whether levels of trace elements in patients with schizophrenia differ from those in healthy individuals.

Data Sources

The PubMed, Scopus, and Web of Science databases were searched to January 2018.

Study Selection

Studies that compared concentrations of trace elements in patients with schizophrenia with those in healthy controls, in patients with schizophrenia under different treatment regimens, or in patients with schizophrenia at different stages of disease were included.

Data Extraction

Data on study and sample characteristics and measures of trace elements were extracted.

Results

Thirty-nine studies with a total of 5151 participants were included. Meta-analysis of combined plasma and serum data showed higher levels of copper, lower levels of iron, and lower levels of zinc among patients with schizophrenia vs controls without schizophrenia. Subgroup analyses confirmed the following: higher levels of copper in plasma, in users of typical antipsychotic drugs, and in males; lower levels of zinc in serum, in patients in Asia, in drug-naive/drug-free patients, and in inpatients; lower levels of iron in serum, in patients in Asia, in drug-naive/drug-free patients, in patients on antipsychotic drugs, in inpatients, in patients with acute or newly diagnosed schizophrenia, in patients with chronic or previously diagnosed schizophrenia, and in males; and lower levels of manganese in plasma and in patients with chronic or previously diagnosed schizophrenia.

Conclusions

This meta-analysis provides evidence of an excess of copper, along with deficiencies of zinc, iron, and manganese, in patients with schizophrenia.