Treatment of antipsychotic-associated hyperglycemia with pioglitazone: a case series

Metabolic syndrome in patients with schizophrenia: Underlying mechanisms and therapeutic approaches (Review)

Schizophrenia (SCZ) represents a considerable health concern, not only due to its impact on cognitive and psychiatric domains, but also because of its association with metabolic abnormalities. Individuals with SCZ face an increased risk of developing metabolic syndrome (MS), which contributes to the increased cardiovascular burden and reduced life expectancy observed in this population. Metabolic alterations are associated with both the SCZ condition itself and extrinsic factors, particularly the use of antipsychotic medications. Additionally, the link between SCZ and MS seems to be guided by distinct genetic parameters. The present narrative review summarizes the relationship between SCZ and MS and emphasizes the various therapeutic approaches for managing its components in patients with these conditions. Recommended therapeutic approaches include lifestyle modifications as the primary strategy, with a focus on behavioral lifestyle programs, addressing dietary patterns and physical activity. Pharmacological interventions include administering common antidiabetic medications and the selection of less metabolically harmful antipsychotics. Alternative interventions with limited clinical application are also discussed. Ultimately, a personalized therapeutic approach encompassing both the psychological and metabolic aspects is essential for the effective management of MS in patients with SCZ.

Immune system and glucose metabolism interaction in schizophrenia: a chicken-egg dilemma

Impaired glucose metabolism and the development of metabolic syndrome contribute to a reduction in the average life expectancy of individuals with schizophrenia. It is unclear whether this association simply reflects an unhealthy lifestyle or whether weight gain and impaired glucose tolerance in patients with schizophrenia are directly attributable to the side effects of atypical antipsychotic medications or disease-inherent derangements. In addition, numerous previous studies have highlighted alterations in the immune system of patients with schizophrenia. Increased concentrations of interleukin (IL)-1, IL-6, and transforming growth factor-beta (TGF-β) appear to be state markers, whereas IL-12, interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), and soluble IL-2 receptor (sIL-2R) appear to be trait markers of schizophrenia. Moreover, the mononuclear phagocyte system (MPS) and microglial activation are involved in the early course of the disease. This review illustrates a "chicken-egg dilemma", as it is currently unclear whether impaired cerebral glucose utilization leads to secondary disturbances in peripheral glucose metabolism, an increased risk of cardiovascular complications, and accompanying pro-inflammatory changes in patients with schizophrenia or whether immune mechanisms may be involved in the initial pathogenesis of schizophrenia, which leads to disturbances in glucose metabolism such as metabolic syndrome. Alternatively, shared underlying factors may be responsible for the co-occurrence of immune system and glucose metabolism disturbances in schizophrenia.

Effects of pioglitazone on metabolic abnormalities, psychopathology, and cognitive function in schizophrenic patients treated with antipsychotic medication: a randomized double-blind study

BACKGROUND

Schizophrenic patients treated with antipsychotic drugs (AP) have an increased frequency of glucose-lipid metabolic abnormalities and diabetes. Pioglitazone has been shown to be effective in the treatment of glucose and lipid abnormalities in diabetes and decreasing longer-term conversion of impaired glucose tolerance to frank diabetes. Some studies also suggest possible pro-cognitive and antidepressant effects of pioglitazone. We studied the effects of pioglitazone on potential metabolic, symptomatic and cognitive benefits in schizophrenic patients treated with AP.

METHODS

54 schizophrenic patients with at least both a)impaired glucose and b) triglycerides≥120mg/dL and/or low HDL levels, participated in a double-blind placebo controlled study of 3month treatment with Pioglitazone (30-45mg/day) or matched placebo, at 5 sites (4 U.S., 1 China). Fasting glucose and lipid parameters, and psychopathology (PANSS scale) were assessed monthly, and patients had a glucose tolerance test and cognitive testing (RBANS and CPT) at baseline and at the end of study. Statistical analysis used mixed model repeated measures analysis, supplemented by completer and LOCF analysis.

RESULTS

In the total sample there was an overall effect (P's<.05 to <.01) of pioglitazone on preventing deterioration in fasting glucose and improving HDL and PANSS depression scores; in the pioglitazone group comparison of baseline vs 3month values also showed significant (P<.05) decreases in fasting insulin, 2h glucose in GTT and insulin resistance (HOMA-IR). However there were marked differences between the responses of patients in the U.S. sites vs the China site. In the U.S. sample, patients treated with pioglitazone, when compared to placebo treated patents, had significantly lower fasting glucose (F=3.99, P=0.02), improved insulin sensitivity (lower H0MA-IR, F=6.24, P=.002), lower triglycerides (F=2.68, P=.06) and increased HDL (F=6.50, P=.001). By the end of the study 52% of the pioglitazone treated patients compared to 15% of the placebo patients had fasting glucose in the normal range (Fisher's exact test P=.02). Pioglitazone also significantly improved PANSS depression factor scores (F=2.82, P=0.05). It did not improve cognitive performance on the RBANS or CPT tasks. Pioglitazone did not increase weight or produce any other significant side-effects. In the small mainland China site sample, pioglitazone treatment, as compared to placebo, did not show greater improvement in metabolic parameters or psychopathology ratings.

CONCLUSIONS

In the sample of patients from the U.S., pioglitazone was an efficacious and safe treatment for glucose and lipid metabolic abnormalities in schizophrenic patients treated with AP, and it may also have beneficial effects on depressive symptoms. It may be particularly useful in patients whose weight gain effects from antipsychotics have plateaued and where weight loss is not the primary goal. The risk vs. benefits of longer term treatment with pioglitazone has to be carefully evaluated for individual patients.

Explorando o componente inflamatório da esquizofrenia

A esquizofrenia é uma doença heterogênea caracterizada por um conjunto de manifestações clínicas. Um grande número de estudos ao longo dos últimos 20 anos apontou para anormalidades no sistema imune em pacientes que sofrem dessa condição. Em adição, tem sido mostrado que a psicose e a disfunção cognitiva associadas com a esquizofrenia estão ligadas a doenças autoimunes. Aqui, revisamos a evidência que sugere que um status pró-inflamatório do sistema imune induz sintomas psicopatológicos e pode estar envolvido na fisiopatologia dessa principal doença mental. Também propomos que futuros estudos pré-clínicos e clínicos deveriam levar em conta tais causas predefinidas e o status do componente inflamatório. Estratificação de pacientes e estratégias de medicina personalizadas baseadas no direcionamento ao componente inflamatório da doença poderiam ajudar na redução de sintomas e da progressão da doença. Por fim, isso poderia levar a novos conceitos na identificação de alvos moleculares em esquizofrenia e estratégias de descoberta de drogas.

[Comorbidity of metabolic syndrome, diabetes and schizophrenia: theoretical and practical considerations]

Schizophrenia is a psychiatric disorder characterized by heterogeneous symptoms, affecting 0.8-1% of the population worldwide. It usually begins in early adulthood and demonstrates a chronic course. In recent years research interest has turned to the increased burden of somatic illness in schizophrenia, with special emphasis on metabolic syndrome and diabetes. In this article I review the theoretical and practical aspects of the comorbidity of schizophrenia with metabolic syndrome and diabetes mellitus. Epidemiological studies demonstrate the occurrence of metabolic syndrome between 22% and 66%, while the prevalence of diabetes is at least threefold compared to the non-psychiatric population in all age groups. Etiologically it is not clear to what extent these alterations are caused by direct genetic and biological effects in contrast to environmental factors. Among the latter the role of atypical antipsychotics should be emphasized. Clinical management of prediabetic conditions and diabetes in schizophrenia warrants the close cooperation of professionals working in the areas of psychiatry and diabetology. This cooperation should include close metabolic monitoring, lifestyle and dietary training, moreover careful modification and in some cases switching of antipsychotic medication. Persisting metabolic symptoms or diabetes require treatment with oral antidiabetics, fibrates, and statins.

S100B Serum Levels in Schizophrenia Are Presumably Related to Visceral Obesity and Insulin Resistance

Elevated blood levels of S100B in schizophrenia have so far been mainly attributed to glial pathology, as S100B is produced by astro- and oligodendroglial cells and is thought to act as a neurotrophic factor with effects on synaptogenesis, dopaminergic and glutamatergic neutrotransmission. However, adipocytes are another important source of S100B since the concentration of S100B in adipose tissue is as high as in nervous tissue. Insulin is downregulating S100B in adipocytes, astrocyte cultures and rat brain. As reviewed in this paper, our recent studies suggest that overweight, visceral obesity, and peripheral/cerebral insulin resistance may be pivotal for at least part of the elevated S100B serum levels in schizophrenia. In the context of this recently identified framework of metabolic disturbances accompanying S100B elevation in schizophrenia, it rather has to be attributed to systemic alterations in glucose metabolism than to be considered a surrogate marker for astrocyte-specific pathologies.