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

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.

Insulin-resistance as a modifiable pathway to cognitive dysfunction in schizophrenia: A systematic review

BACKGROUND

Cognitive deficits are difficult to treat and negatively influence quality of life and functional outcomes of persons with schizophrenia. In the last twenty years, extensive literature demonstrated that persons with diabetes and insulin resistance (IR) also display cognitive deficits. Being type 2 diabetes (T2DM) and IR highly frequent in persons with schizophrenia, it is plausible to hypothesize that these conditions might play a role in determining dyscognition. If that is the case, acting on glucose dysmetabolism may eventually improve cognitive functioning. This review aims at: 1. evaluating the association between IR or T2DM and cognitive dysfunction in schizophrenia; 2. reviewing the evidence that pharmacological treatment of IR or T2DM may improve dyscognition in schizophrenia.

METHODS

Two systematic searches were conducted in PubMed, PsycInfo, and Scopus. We followed the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines.

RESULTS

From the first search we included 17 studies, 8 on the effects of T2DM and 9 on the effects of IR-other prediabetes measures on cognition in persons with schizophrenia. From the second search we included 12 studies investigating the effect on cognition of glucose (4 studies), insulin (2 studies), metformin (2 studies), PPAR-γ agonists (2 studies), GLP-1 agonist (1 study), bromocriptine (1 study).

CONCLUSIONS

T2DM was associated with worse cognitive function in persons with schizophrenia, while IR was less strongly associated with cognitive dysfunction. Evidence regarding the efficacy of glucose-lowering medications on cognition in schizophrenia is inconclusive, yet methodological issues likely contribute to explain conflicting results.

Unlocking new avenues for neuropsychiatric disease therapy: the emerging potential of Peroxisome proliferator-activated receptors as promising therapeutic targets

RATIONALE

Peroxisome proliferator-activated receptors (PPARs) are transcription factors that regulate various physiological processes such as inflammation, lipid metabolism, and glucose homeostasis. Recent studies suggest that targeting PPARs could be beneficial in treating neuropsychiatric disorders by modulating neuronal function and signaling pathways in the brain. PPAR-α, PPAR-δ, and PPAR-γ have been found to play important roles in cognitive function, neuroinflammation, and neuroprotection. Dysregulation of PPARs has been associated with neuropsychiatric disorders like bipolar disorder, schizophrenia, major depression disorder, and autism spectrum disorder. The limitations and side effects of current treatments have prompted research to target PPARs as a promising novel therapeutic strategy. Preclinical and clinical studies have shown the potential of PPAR agonists and antagonists to improve symptoms associated with these disorders.

OBJECTIVE

This review aims to provide an overview of the current understanding of PPARs in neuropsychiatric disorders, their potential as therapeutic targets, and the challenges and future directions for developing PPAR-based therapies.

METHODS

An extensive literature review of various search engines like PubMed, Medline, Bentham, Scopus, and EMBASE (Elsevier) databases was carried out with the keywords "PPAR, Neuropsychiatric disorders, Oxidative stress, Inflammation, Bipolar Disorder, Schizophrenia, Major depression disorder, Autism spectrum disorder, molecular pathway".

RESULT & CONCLUSION

Although PPARs present a hopeful direction for innovative therapeutic approaches in neuropsychiatric conditions, additional research is required to address obstacles and convert this potential into clinically viable and individualized treatments.

Metabolic complications of psychotropic medications in psychiatric disorders: Emerging role of de novo lipogenesis and therapeutic consideration

Although significant advances have been made in understanding the patho-physiology of psychiatric disorders (PDs), therapeutic advances have not been very convincing. While psychotropic medications can reduce classical symptoms in patients with PDs, their long-term use has been reported to induce or exaggerate various pre-existing metabolic abnormalities including diabetes, obesity and non-alcoholic fatty liver disease (NAFLD). The mechanism(s) underlying these metabolic abnormalities is not clear; however, lipid/fatty acid accumulation due to enhanced de novo lipogenesis (DNL) has been shown to reduce membrane fluidity, increase oxidative stress and inflammation leading to the development of the aforementioned metabolic abnormalities. Intriguingly, emerging evidence suggest that DNL dysregulation and fatty acid accumulation could be the major mechanisms associated with the development of obesity, diabetes and NAFLD after long-term treatment with psychotropic medications in patients with PDs. In support of this, several adjunctive drugs comprising of anti-oxidants and anti-inflammatory agents, that are used in treating PDs in combination with psychotropic medications, have been shown to reduce insulin resistance and development of NAFLD. In conclusion, the above evidence suggests that DNL could be a potential pathological factor associated with various metabolic abnormalities, and a new avenue for translational research and therapeutic drug designing in PDs.

Ketogenic Diet Intervention on Metabolic and Psychiatric Health in Bipolar and Schizophrenia: A Pilot Trial

The ketogenic diet (KD, also known as metabolic therapy) has been successful in the treatment of obesity, type 2 diabetes, and epilepsy. More recently, this treatment has shown promise in the treatment of psychiatric illness. We conducted a 4-month pilot study to investigate the effects of a KD on individuals with schizophrenia or bipolar disorder with existing metabolic abnormalities. Twenty-three participants were enrolled in a single-arm trial. Results showcased improvements in metabolic health, with no participants meeting metabolic syndrome criteria by study conclusion. Adherent individuals experienced significant reduction in weight (12 %), BMI (12 %), waist circumference (13 %), and visceral adipose tissue (36 %). Observed biomarker enhancements in this population include a 27 % decrease in HOMA-IR, and a 25 % drop in triglyceride levels. In psychiatric measurements, participants with schizophrenia showed a 32 % reduction in Brief Psychiatric Rating Scale scores. Overall Clinical Global Impression (CGI) severity improved by an average of 31 %, and the proportion of participants that started with elevated symptomatology improved at least 1-point on CGI (79 %). Psychiatric outcomes across the cohort encompassed increased life satisfaction (17 %) and enhanced sleep quality (19 %). This pilot trial underscores the potential advantages of adjunctive ketogenic dietary treatment in individuals grappling with serious mental illness.

Lactate levels in the brain and blood of schizophrenia patients: A systematic review and meta-analysis

BACKGROUND

The pathophysiological mechanisms of schizophrenia are still unclear. Converging evidence suggests that energy metabolism abnormalities are involved in schizophrenia, and support its role in the pathophysiology of this disease. Lactate plays an important role in energy metabolism. Many studies have reported changes in the levels of lactate in the brain and serum of schizophrenia patients; however, the results from these studies are not consistent. To overcome this limitation, the goal of the present meta-analysis is to analyze the changes in lactate levels in the brain and blood of schizophrenia patients.

METHODS

For this systematic review and meta-analysis, we performed a thorough search of relevant literature in the English language, using the MEDLINE, Cochrane, and Embase databases.

RESULTS

In the present meta-analysis, 20 studies were scrutinized, including 13 studies on brain lactate levels, which involved 322 schizophrenia patients and 324 healthy individuals as controls. 7 studies on blood lactate levels, involving 234 schizophrenia patients and 238 healthy individuals, were also included. Brain lactate levels were elevated in schizophrenia patients, both in vivo and in post-mortem studies. Nevertheless, blood lactate levels in schizophrenia patients have revealed no statistically significant difference, as compared with control individuals.

CONCLUSIONS

In comparison with healthy individuals, schizophrenia patients had higher lactate levels in the brain, rather than in the blood. These findings suggest independent regulatory mechanisms of lactate levels in the brain and peripheral tissues. Abnormal lactate metabolism in the brain may be an important pathological mechanism in schizophrenia.

Central insulin dysregulation in antipsychotic-naïve first-episode psychosis: In silico exploration of gene expression signatures

Antipsychotic drug (AP)-naïve first-episode psychosis (FEP) patients display premorbid cognitive dysfunctions and dysglycemia. Brain insulin resistance may link metabolic and cognitive disorders in humans. This suggests that central insulin dysregulation represents a component of the pathophysiology of psychosis spectrum disorders (PSDs). Nonetheless, the links between central insulin dysregulation, dysglycemia, and cognitive deficits in PSDs are poorly understood. We investigated whether AP-naïve FEP patients share overlapping brain gene expression signatures with central insulin perturbation (CIP) in rodent models. We systematically compiled and meta-analyzed peripheral transcriptomic datasets of AP-naïve FEP patients along with hypothalamic and hippocampal datasets of CIP rodent models to identify common transcriptomic signatures. The common signatures were used for pathway analysis and to identify potential drug treatments with discordant (reverse) signatures. AP-naïve FEP and CIP (hypothalamus and hippocampus) shared 111 and 346 common signatures respectively, which were associated with pathways related to inflammation, endoplasmic reticulum stress, and neuroplasticity. Twenty-two potential drug treatments were identified, including antidiabetic agents. The pathobiology of PSDs may include central insulin dysregulation, which contribute to dysglycemia and cognitive dysfunction independently of AP treatment. The identified treatments may be tested in early psychosis patients to determine if dysglycemia and cognitive deficits can be mitigated.

Pharmacological interventions for prevention of weight gain in people with schizophrenia

BACKGROUND

Antipsychotic-induced weight gain is an extremely common problem in people with schizophrenia and is associated with increased morbidity and mortality. Adjunctive pharmacological interventions may be necessary to help manage antipsychotic-induced weight gain. This review splits and updates a previous Cochrane Review that focused on both pharmacological and behavioural approaches to this problem.

OBJECTIVES

To determine the effectiveness of pharmacological interventions for preventing antipsychotic-induced weight gain in people with schizophrenia.

SEARCH METHODS

The Cochrane Schizophrenia Information Specialist searched Cochrane Schizophrenia's Register of Trials on 10 February 2021. There are no language, date, document type, or publication status limitations for inclusion of records in the register.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) that examined any adjunctive pharmacological intervention for preventing weight gain in people with schizophrenia or schizophrenia-like illnesses who use antipsychotic medications.

DATA COLLECTION AND ANALYSIS

At least two review authors independently extracted data and assessed the quality of included studies. For continuous outcomes, we combined mean differences (MD) in endpoint and change data in the analysis. For dichotomous outcomes, we calculated risk ratios (RR). We assessed risk of bias for included studies and used GRADE to judge certainty of evidence and create summary of findings tables. The primary outcomes for this review were clinically important change in weight, clinically important change in body mass index (BMI), leaving the study early, compliance with treatment, and frequency of nausea. The included studies rarely reported these outcomes, so, post hoc, we added two new outcomes, average endpoint/change in weight and average endpoint/change in BMI.

MAIN RESULTS

Seventeen RCTs, with a total of 1388 participants, met the inclusion criteria for the review. Five studies investigated metformin, three topiramate, three H2 antagonists, three monoamine modulators, and one each investigated monoamine modulators plus betahistine, melatonin and samidorphan. The comparator in all studies was placebo or no treatment (i.e. standard care alone). We synthesised all studies in a quantitative meta-analysis. Most studies inadequately reported their methods of allocation concealment and blinding of participants and personnel. The resulting risk of bias and often small sample sizes limited the overall certainty of the evidence. Only one reboxetine study reported the primary outcome, number of participants with clinically important change in weight. Fewer people in the treatment condition experienced weight gains of more than 5% and more than 7% of their bodyweight than those in the placebo group (> 5% weight gain RR 0.27, 95% confidence interval (CI) 0.11 to 0.65; 1 study, 43 participants; > 7% weight gain RR 0.24, 95% CI 0.07 to 0.83; 1 study, 43 participants; very low-certainty evidence). No studies reported the primary outcomes, 'clinically important change in BMI', or 'compliance with treatment'. However, several studies reported 'average endpoint/change in body weight' or 'average endpoint/change in BMI'. Metformin may be effective in preventing weight gain (MD -4.03 kg, 95% CI -5.78 to -2.28; 4 studies, 131 participants; low-certainty evidence); and BMI increase (MD -1.63 kg/m2, 95% CI -2.96 to -0.29; 5 studies, 227 participants; low-certainty evidence). Other agents that may be slightly effective in preventing weight gain include H2 antagonists such as nizatidine, famotidine and ranitidine (MD -1.32 kg, 95% CI -2.09 to -0.56; 3 studies, 248 participants; low-certainty evidence) and monoamine modulators such as reboxetine and fluoxetine (weight: MD -1.89 kg, 95% CI -3.31 to -0.47; 3 studies, 103 participants; low-certainty evidence; BMI: MD -0.66 kg/m2, 95% CI -1.05 to -0.26; 3 studies, 103 participants; low-certainty evidence). Topiramate did not appear effective in preventing weight gain (MD -4.82 kg, 95% CI -9.99 to 0.35; 3 studies, 168 participants; very low-certainty evidence). For all agents, there was no difference between groups in terms of individuals leaving the study or reports of nausea. However, the results of these outcomes are uncertain given the very low-certainty evidence.

AUTHORS' CONCLUSIONS

There is low-certainty evidence to suggest that metformin may be effective in preventing weight gain. Interpretation of this result and those for other agents, is limited by the small number of studies, small sample size, and short study duration. In future, we need studies that are adequately powered and with longer treatment durations to further evaluate the efficacy and safety of interventions for managing weight gain.

Schizophrenia: a disorder of broken brain bioenergetics

A substantial and diverse body of literature suggests that the pathophysiology of schizophrenia is related to deficits of bioenergetic function. While antipsychotics are an effective therapy for the management of positive psychotic symptoms, they are not efficacious for the complete schizophrenia symptom profile, such as the negative and cognitive symptoms. In this review, we discuss the relationship between dysfunction of various metabolic pathways across different brain regions in relation to schizophrenia. We contend that several bioenergetic subprocesses are affected across the brain and such deficits are a core feature of the illness. We provide an overview of central perturbations of insulin signaling, glycolysis, pentose-phosphate pathway, tricarboxylic acid cycle, and oxidative phosphorylation in schizophrenia. Importantly, we discuss pharmacologic and nonpharmacologic interventions that target these pathways and how such interventions may be exploited to improve the symptoms of schizophrenia.

Astrocyte Bioenergetics and Major Psychiatric Disorders

Ongoing research continues to add new elements to the emerging picture of involvement of astrocyte energy metabolism in the pathophysiology of major psychiatric disorders, including schizophrenia, mood disorders, and addictions. This review outlines what is known about the energy metabolism in astrocytes, the most numerous cell type in the brain, and summarizes the recent work on how specific perturbations of astrocyte bioenergetics may contribute to the neuropsychiatric conditions. The role of astrocyte energy metabolism in mental health and disease is reviewed on the organism, organ, and cell level. Data arising from genomic, metabolomic, in vitro, and neurobehavioral studies is critically analyzed to suggest future directions in research and possible metabolism-focused therapeutic interventions.

Repurposing Peroxisome Proliferator-Activated Receptor Agonists in Neurological and Psychiatric Disorders

Common pathophysiological mechanisms have emerged for different neurological and neuropsychiatric conditions. In particular, mechanisms of oxidative stress, immuno-inflammation, and altered metabolic pathways converge and cause neuronal and non-neuronal maladaptative phenomena, which underlie multifaceted brain disorders. The peroxisome proliferator-activated receptors (PPARs) are nuclear receptors modulating, among others, anti-inflammatory and neuroprotective genes in diverse tissues. Both endogenous and synthetic PPAR agonists are approved treatments for metabolic and systemic disorders, such as diabetes, fatty liver disease, and dyslipidemia(s), showing high tolerability and safety profiles. Considering that some PPAR-acting drugs permeate through the blood-brain barrier, the possibility to extend their scope from the periphery to central nervous system has gained interest in recent years. Here, we review preclinical and clinical evidence that PPARs possibly exert a neuroprotective role, thereby providing a rationale for repurposing PPAR-targeting drugs to counteract several diseases affecting the central nervous system.

Pharmacological Management of Glucose Dysregulation in Patients Treated with Second-Generation Antipsychotics

Fasting hyperglycemia, impaired glucose tolerance, prediabetes, and diabetes are frequently present in patients treated with second-generation antipsychotics (SGAPs) for schizophrenia, bipolar disorder, and other severe mental illnesses. These drugs are known to produce weight gain, which may lead to insulin resistance, glucose intolerance, and metabolic syndrome, which constitute important risk factors for the emergence of diabetes. The aim of this review was to formulate therapeutic guidelines for the management of diabetes in patients treated with SGAPs, based on the association between SGAP-induced weight gain and glucose dysregulation. A  systematic search in PubMed from inception to March 2020 for randomized controlled trials (RCTs) of diabetes or prediabetes in patients treated with SGAPs was performed. PubMed was also searched for the most recent clinical practice guidelines of interventions for co-morbid conditions associated with diabetes mellitus (DM) (arterial hypertension and dyslipidemia), lifestyle interventions and switching from high metabolic liability SGAPs to safer SGAPs. The search identified 14 RCTs in patients treated with SGAPs. Drug therapy using metformin as first-line therapy and glucagon-like peptide-1 receptor agonists (GLP-1 RAs) or perhaps sodium-glucose cotransporter-2 (SGLT2) inhibitors as add-on therapy, might be preferred in these patients as well, as they favorably influence glucose metabolism and body mass index, and provide cardio-renal benefits in general to the DM population, although for the SGLT-2 inhibitors there are no RCTs in this specific patient category so far. Metformin is also useful for treatment of prediabetes. Arterial hypertension should be treated with angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers, and statins should be used for correction of dyslipidemia. The outcome of lifestyle-changing interventions has been disappointing. Switching from clozapine, olanzapine, or quetiapine to lower cardiometabolic-risk SGAPs, like aripiprazole, brexpiprazole, cariprazine, lurasidone, or ziprasidone, has been recommended.

Interventions for preventing type 2 diabetes in adults with mental disorders in low- and middle-income countries

BACKGROUND

The prevalence of type 2 diabetes is increased in individuals with mental disorders. Much of the burden of disease falls on the populations of low- and middle-income countries (LMICs).

OBJECTIVES

To assess the effects of pharmacological, behaviour change, and organisational interventions versus active and non-active comparators in the prevention or delay of type 2 diabetes among people with mental illness in LMICs.

SEARCH METHODS

We searched the Cochrane Common Mental Disorders Controlled Trials Register, CENTRAL, MEDLINE, Embase and six other databases, as well as three international trials registries. We also searched conference proceedings and checked the reference lists of relevant systematic reviews. Searches are current up to 20 February 2020.

SELECTION CRITERIA

Randomized controlled trials (RCTs) of pharmacological, behavioural or organisational interventions targeting the prevention or delay of type 2 diabetes in adults with mental disorders in LMICs.

DATA COLLECTION AND ANALYSIS

Pairs of review authors working independently performed data extraction and risk of bias assessments. We conducted meta-analyses using random-effects models.

MAIN RESULTS

One hospital-based RCT with 150 participants (99 participants with schizophrenia) addressed our review's primary outcome of prevention or delay of type 2 diabetes onset. Low-certainty evidence from this study did not show a difference between atypical and typical antipsychotics in the development of diabetes at six weeks (risk ratio (RR) 0.46, 95% confidence interval (CI) 0.03 to 7.05) (among a total 99 participants with schizophrenia, 68 were in atypical and 31 were in typical antipsychotic groups; 55 participants without mental illness were not considered in the analysis). An additional 29 RCTs with 2481 participants assessed one or more of the review's secondary outcomes. All studies were conducted in hospital settings and reported on pharmacological interventions. One study, which we could not include in our meta-analysis, included an intervention with pharmacological and behaviour change components. We identified no studies of organisational interventions. Low- to moderate-certainty evidence suggests there may be no difference between the use of atypical and typical antipsychotics for the outcomes of drop-outs from care (RR 1.31, 95% CI 0.63 to 2.69; two studies with 144 participants), and fasting blood glucose levels (mean difference (MD) 0.05 lower, 95% CI 0.10 to 0.00; two studies with 211 participants). Participants who receive typical antipsychotics may have a lower body mass index (BMI) at follow-up than participants who receive atypical antipsychotics (MD 0.57, 95% CI 0.33 to 0.81; two studies with 141 participants; moderate certainty of evidence), and may have lower total cholesterol levels eight weeks after starting treatment (MD 0.35, 95% CI 0.27 to 0.43; one study with 112 participants). There was moderate certainty evidence suggesting no difference between the use of metformin and placebo for the outcomes of drop-outs from care (RR 1.22, 95% CI 0.09 to 16.35; three studies with 158 participants). There was moderate-to-high certainty evidence of no difference between metformin and placebo for fasting blood glucose levels (endpoint data: MD -0.35, 95% CI -0.60 to -0.11; change from baseline data: MD 0.01, 95% CI -0.21 to 0.22; five studies with 264 participants). There was high certainty evidence that BMI was lower for participants receiving metformin compared with those receiving a placebo (MD -1.37, 95% CI -2.04 to -0.70; five studies with 264 participants; high certainty of evidence). There was no difference between metformin and placebo for the outcomes of waist circumference, blood pressure and cholesterol levels. Low-certainty evidence from one study (48 participants) suggests there may be no difference between the use of melatonin and placebo for the outcome of drop-outs from care (RR 1.00, 95% CI 0.38 to 2.66). Fasting blood glucose is probably reduced more in participants treated with melatonin compared with placebo (endpoint data: MD -0.17, 95% CI -0.35 to 0.01; change from baseline data: MD -0.24, 95% CI -0.39 to -0.09; three studies with 202 participants, moderate-certainty evidence). There was no difference between melatonin and placebo for the outcomes of waist circumference, blood pressure and cholesterol levels. Very low-certainty evidence from one study (25 participants) suggests that drop-outs may be higher in participants treated with a tricyclic antidepressant (TCA) compared with those receiving a selective serotonin reuptake inhibitor (SSRI) (RR 0.34, 95% CI 0.11 to 1.01). It is uncertain if there is no difference in fasting blood glucose levels between these groups (MD -0.39, 95% CI -0.88 to 0.10; three studies with 141 participants, moderate-certainty evidence). It is uncertain if there is no difference in BMI and depression between the TCA and SSRI antidepressant groups.

AUTHORS' CONCLUSIONS

Only one study reported data on our primary outcome of interest, providing low-certainty evidence that there may be no difference in risk between atypical and typical antipsychotics for the outcome of developing type 2 diabetes. We are therefore not able to draw conclusions on the prevention of type 2 diabetes in people with mental disorders in LMICs. For studies reporting on secondary outcomes, there was evidence of risk of bias in the results. There is a need for further studies with participants from LMICs with mental disorders, particularly on behaviour change and on organisational interventions targeting prevention of type 2 diabetes in these populations.

Pharmacological Interventions to Treat Antipsychotic-Induced Dyslipidemia in Schizophrenia Patients: A Systematic Review and Meta Analysis

Introduction: Antipsychotic-induced dyslipidemia represents a common adverse effect faced by patients with schizophrenia that increases risk for developing further metabolic complications and cardiovascular disease. Despite its burden, antipsychotic-induced dyslipidemia is often left untreated, and the effectiveness of pharmacological interventions for mitigating dyslipidemia has not been well-addressed. This review aims to assess the effectiveness of pharmacological interventions in alleviating dyslipidemia in patients with schizophrenia. Methods: Medline, PsychInfo, and EMBASE were searched for all relevant English articles from 1950 to November 2020. Randomized placebo-controlled trials were included. Differences in changes in triglycerides, HDL cholesterol, LDL cholesterol, and VLDL cholesterol levels between treatment and placebo groups were meta-analyzed as primary outcomes. Results: Our review identified 48 randomized controlled trials that comprised a total of 3,128 patients and investigated 29 pharmacological interventions. Overall, pharmacological interventions were effective in lowering LDL cholesterol, triglycerides, and total cholesterol levels while increasing the levels of HDL cholesterol. Within the intervention subgroups, approved lipid-lowering agents did not reduce lipid parameters other than total cholesterol level, while antipsychotic switching and antipsychotic add-on interventions improved multiple lipid parameters, including triglycerides, LDL cholesterol, HDL cholesterol, and total cholesterol. Off label lipid lowering agents improved triglycerides and total cholesterol levels, with statistically significant changes seen with metformin. Conclusion: Currently available lipid lowering agents may not work as well in patients with schizophrenia who are being treated with antipsychotics. Additionally, antipsychotic switching, antipsychotic add-ons, and certain off label interventions might be more effective in improving some but not all associated lipid parameters. Future studies should explore novel interventions for effectively managing antipsychotic-induced dyslipidemia. Registration: PROSPERO 2020 CRD42020219982; https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020219982.

Efficacy and safety of anti-inflammatory agents in treatment of psychotic disorders - A comprehensive systematic review and meta-analysis

OBJECTIVE

Antipsychotic effects of immunomodulating drugs have been suggested; however, a thorough, comprehensive meta-analysis on the effect and safety of anti-inflammatory add-on treatment on psychotic disorders is lacking.

METHOD

Multiple databases were searched up until February 2020. Only double-blinded, randomized, placebo-controlled clinical trials (RCTs) were included. Primary outcomes were change in total psychopathology and adverse events. Secondary outcomes included, amongst others, positive and negative symptoms, general psychopathology and cognitive domains. We performed random-effects meta-analyses estimating mean differences (MD) and standardized mean differences (SMD) for effect sizes.

RESULTS

Seventy RCTs (N = 4104) were included, investigating either primarily anti-inflammatory drugs, i.e. drugs developed for immunomodulation, such as NSAIDs, minocycline and monoclonal antibodies (k = 15), or drugs with potential anti-inflammatory properties (k = 55), e.g. neurosteroids, N-acetyl cysteine, estrogens, fatty acids, statins, and glitazones. Antipsychotics plus anti-inflammatory treatment, compared to antipsychotics plus placebo, was associated with a PANSS scale MD improvement of -4.57 (95%CI = -5.93 to -3.20) points, corresponding to a SMD effect size of -0.29 (95%CI = -0.40 to -0.19). Trials on schizophrenia (MD = -6.80; 95%CI, -9.08 to -4.52) showed greater improvement (p < 0.01) than trials also including other psychotic disorders. However, primarily anti-inflammatory drugs (MD = 4.00; 95%CI = -7.19 to -0.80) were not superior (p = 0.69) to potential anti-inflammatory drugs (MD = 4.71; 95%CI = -6.26 to -3.17). Furthermore, meta-regression found that smaller studies showed significantly larger effect sizes than the larger studies (p = 0.0085), and only 2 studies had low risk of bias on all domains. Small but significant effects were found on negative symptoms (MD = -1.29), positive symptoms (MD = -0.53), general psychopathology (MD = -1.50) and working memory (SMD = 0.21). No differences were found regarding adverse events, but only 26 studies reported hereon.

CONCLUSIONS

Anti-inflammatory add-on treatment to antipsychotics showed improvement of psychotic disorders; however, no superiority was found in primarily anti-inflammatory drugs, raising the question of the mechanism behind the effect, and treatment effect might be overestimated due to the large number of small studies.

Evidence for altered energy metabolism, increased lactate, and decreased pH in schizophrenia brain: A focused review and meta-analysis of human postmortem and magnetic resonance spectroscopy studies

Though the pathophysiology of schizophrenia remains poorly understood, altered brain energy metabolism is increasingly implicated. Here, we conduct meta-analyses of the available human studies measuring lactate or pH in schizophrenia brain and discuss the accumulating evidence for increased lactate and decreased pH in schizophrenia brain and evidence linking these to negative and cognitive symptom severity. Meta-analysis of six postmortem studies revealed a significant increase in lactate in schizophrenia brain while meta-analysis of 14 magnetic resonance spectroscopy studies did not reveal a significant change in brain pH in schizophrenia. However, only five of these studies were likely sufficiently powered to detect differences in brain pH, and meta-analysis of these five studies found a nonsignificant decrease in pH in schizophrenia brain. Next, we discuss evidence for altered brain energy metabolism in schizophrenia and how this may underlie a buildup of lactate and decreased pH. This alteration, similar to the Warburg effect extensively described in cancer biology, involves diminished tricarboxylic acid cycle and oxidative phosphorylation along with a shift toward increased reliance on glycolysis for energy production. We then explore the role that mitochondrial dysfunction, oxidative stress, and hypoxia-related changes in gene expression likely play in this shift in brain energy metabolism and address the functional consequences of lowered brain pH in schizophrenia including alterations in neurotransmitter regulation, mRNA stability, and overall patterns of gene expression. Finally, we discuss how altered energy metabolism in schizophrenia brain may serve as an effective target in the treatment of this illness.

Steroid receptor RNA activator affects the development of poststroke depression by regulating the peroxisome proliferator-activated receptor γ signaling pathway

The long noncoding RNA, steroid receptor RNA activator (SRA), has been reported to be involved in the development of many types of disease in humans. The aim of this study was to evaluate whether SRA was associated with poststroke depression (PSD). A PSD rat model was established, and depression-like behaviors and sucrose consumption in rats with PSD were analyzed. Reverse transcription-quantitative PCR (RT-PCR), western blot and luciferase dual reporter assay analyses were performed to detect the expression of peroxisome proliferator-activated receptor γ (PPARγ) expression following SRA small interfering RNA (siRNA) treatment. Compared with the control, the horizontal and vertical movement scores and consumption of sucrose solution were decreased in the PSD, PSD + LV-SRA and PSD + pioglitazone groups at 7 days post-SRA-siRNA treatment, while they were increased in the PSD + LV-SRA and PSD + pioglitazone groups. Furthermore, SRA expression in the PSD, PSD + LV-SRA and PSD + pioglitazone groups was lowered compared with the control group at 7 days postinjection. SRA increased the reported luciferase activity, but pioglitazone had no effect on the luciferase activity induced by SRA. SRA upregulated PPARγ mRNA and protein expression, whereas SRA siRNA significantly downregulated its expression. No significant differences in characteristics were identified between rats with and without PSD. SRA was more highly expressed in rats with PSD than rats without PSD. Collectively, this study suggests that SRA is associated with PSD through PPARγ signaling, indicating a potential therapeutic target of SRA for controlling PSD.

PPARγ and Cognitive Performance

Recent findings have led to the discovery of many signaling pathways that link nuclear receptors with human conditions, including mental decline and neurodegenerative diseases. PPARγ agonists have been indicated as neuroprotective agents, supporting synaptic plasticity and neurite outgrowth. For these reasons, many PPARγ ligands have been proposed for the improvement of cognitive performance in different pathological conditions. In this review, the research on this issue is extensively discussed.

Exploration and Development of PPAR Modulators in Health and Disease: An Update of Clinical Evidence

Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors that govern the expression of genes responsible for energy metabolism, cellular development, and differentiation. Their crucial biological roles dictate the significance of PPAR-targeting synthetic ligands in medical research and drug discovery. Clinical implications of PPAR agonists span across a wide range of health conditions, including metabolic diseases, chronic inflammatory diseases, infections, autoimmune diseases, neurological and psychiatric disorders, and malignancies. In this review we aim to consolidate existing clinical evidence of PPAR modulators, highlighting their clinical prospects and challenges. Findings from clinical trials revealed that different agonists of the same PPAR subtype could present different safety profiles and clinical outcomes in a disease-dependent manner. Pemafibrate, due to its high selectivity, is likely to replace other PPARα agonists for dyslipidemia and cardiovascular diseases. PPARγ agonist pioglitazone showed tremendous promises in many non-metabolic disorders like chronic kidney disease, depression, inflammation, and autoimmune diseases. The clinical niche of PPARβ/δ agonists is less well-explored. Interestingly, dual- or pan-PPAR agonists, namely chiglitazar, saroglitazar, elafibranor, and lanifibranor, are gaining momentum with their optimistic outcomes in many diseases including type 2 diabetes, dyslipidemia, non-alcoholic fatty liver disease, and primary biliary cholangitis. Notably, the preclinical and clinical development for PPAR antagonists remains unacceptably deficient. We anticipate the future design of better PPAR modulators with minimal off-target effects, high selectivity, superior bioavailability, and pharmacokinetics. This will open new possibilities for PPAR ligands in medicine.

Neuron-specific deficits of bioenergetic processes in the dorsolateral prefrontal cortex in schizophrenia

Schizophrenia is a devastating illness that affects over 2 million people in the United States and costs society billions of dollars annually. New insights into the pathophysiology of schizophrenia are needed to provide the conceptual framework to facilitate development of new treatment strategies. We examined bioenergetic pathways in the dorsolateral prefrontal cortex (DLPFC) of subjects with schizophrenia and control subjects using western blot analysis, quantitative real-time polymerase chain reaction, and enzyme/substrate assays. Laser-capture microdissection-quantitative polymerase chain reaction was used to examine these pathways at the cellular level. We found decreases in hexokinase (HXK) and phosphofructokinase (PFK) activity in the DLPFC, as well as decreased PFK1 mRNA expression. In pyramidal neurons, we found an increase in monocarboxylate transporter 1 mRNA expression, and decreases in HXK1, PFK1, glucose transporter 1 (GLUT1), and GLUT3 mRNA expression. These results suggest abnormal bioenergetic function, as well as a neuron-specific defect in glucose utilization, in the DLPFC in schizophrenia.

Connectivity Analyses of Bioenergetic Changes in Schizophrenia: Identification of Novel Treatments

We utilized a cell-level approach to examine glycolytic pathways in the DLPFC of subjects with schizophrenia (n = 16) and control (n = 16) and found decreased mRNA expression of glycolytic enzymes in pyramidal neurons, but not astrocytes. To replicate these novel bioenergetic findings, we probed independent datasets for bioenergetic targets and found similar abnormalities. Next, we used a novel strategy to build a schizophrenia bioenergetic profile by a tailored application of the Library of Integrated Network-Based Cellular Signatures data portal (iLINCS) and investigated connected cellular pathways, kinases, and transcription factors using Enrichr. Finally, with the goal of identifying drugs capable of "reversing" the bioenergetic schizophrenia signature, we performed a connectivity analysis with iLINCS and identified peroxisome proliferator-activated receptor (PPAR) agonists as promising therapeutic targets. We administered a PPAR agonist to the GluN1 knockdown model of schizophrenia and found it improved long-term memory. Taken together, our findings suggest that tailored bioinformatics approaches, coupled with the LINCS library of transcriptional signatures of chemical and genetic perturbagens, may be employed to identify novel treatment strategies for schizophrenia and related diseases.

Brain insulin action: Implications for the treatment of schizophrenia

Insulin action in the central nervous system is a major regulator of energy balance and cognitive processes. The development of central insulin resistance is associated with alterations in dopaminergic reward systems and homeostatic signals affecting food intake, glucose metabolism, body weight and cognitive performance. Emerging evidence has highlighted a role for antipsychotics (APs) to modulate central insulin-mediated pathways. Although APs remain the cornerstone treatment for schizophrenia they are associated with severe metabolic complications and fail to address premorbid cognitive deficits, which characterize the disorder of schizophrenia. In this review, we first explore how the hypothesized association between schizophrenia and CNS insulin dysregulation aligns with the use of APs. We then investigate the proposed relationship between CNS insulin action and AP-mediated effects on metabolic homeostasis, and different domains of psychopathology, including cognition. We briefly discuss a potential role of CNS insulin signaling to explain the hypothesized, but somewhat controversial association between therapeutic efficacy and metabolic side effects of APs. Finally, we propose how this knowledge might inform novel treatment strategies to target difficult to treat domains of schizophrenia. This article is part of the issue entitled 'Special Issue on Antipsychotics'.

Primary care management of cardiovascular risk for people with severe mental illnesses: the Primrose research programme including cluster RCT

Background

Effective interventions are needed to prevent cardiovascular disease (CVD) in people with severe mental illnesses (SMI) because their risk of CVD is higher than that of the general population.

Objectives

(1) Develop and validate risk models for predicting CVD events in people with SMI and evaluate their cost-effectiveness, (2) develop an intervention to reduce levels of cholesterol and CVD risk in SMI and (3) test the clinical effectiveness and cost-effectiveness of this new intervention in primary care.

Design

Mixed methods with patient and public involvement throughout. The mixed methods were (1) a prospective cohort and risk score validation study and cost-effectiveness modelling, (2) development work (focus groups, updated systematic review of interventions, primary care database studies investigating statin prescribing and effectiveness) and (3) cluster randomised controlled trial (RCT) assessing the clinical effectiveness and cost-effectiveness of a new practitioner-led intervention, and fidelity assessment of audio-recorded appointments.

Setting

General practices across England.

Participants

All studies included adults with SMI (schizophrenia, bipolar disorder or other non-organic psychosis). The RCT included adults with SMI and two or more CVD risk factors.

Interventions

The intervention consisted of 8–12 appointments with a practice nurse/health-care assistant over 6 months, involving collaborative behavioural approaches to CVD risk factors. The intervention was compared with routine practice with a general practitioner (GP).

Main outcome measures

The primary outcome for the risk score work was CVD events, in the cost-effectiveness modelling it was quality-adjusted life-years (QALYs) and in the RCT it was level of total cholesterol.

Data sources

Databases studies used The Health Improvement Network (THIN). Intervention development work included focus groups and systematic reviews. The RCT collected patient self-reported and routine NHS GP data. Intervention appointments were audio-recorded.

Results

Two CVD risk score models were developed and validated in 38,824 people with SMI in THIN: the Primrose lipid model requiring cholesterol levels, and the Primrose body mass index (BMI) model with no blood test. These models performed better than published Cox Framingham models. In health economic modelling, the Primrose BMI model was most cost-effective when used as an algorithm to drive statin prescriptions. Focus groups identified barriers to, and facilitators of, reducing CVD risk in SMI including patient engagement and motivation, staff confidence, involving supportive others, goal-setting and continuity of care. Findings were synthesised with evidence from updated systematic reviews to create the Primrose intervention and training programme. THIN cohort studies in 16,854 people with SMI demonstrated that statins effectively reduced levels of cholesterol, with similar effect sizes to those in general population studies over 12–24 months (mean decrease 1.2 mmol/l). Cluster RCT: 76 GP practices were randomised to the Primrose intervention (n = 38) or treatment as usual (TAU) (n = 38). The primary outcome (level of cholesterol) was analysed for 137 out of 155 participants in Primrose and 152 out of 172 in TAU. There was no difference in levels of cholesterol at 12 months [5.4 mmol/l Primrose vs. 5.5 mmol/l TAU; coefficient 0.03; 95% confidence interval (CI) –0.22 to 0.29], nor in secondary outcomes related to cardiometabolic parameters, well-being or medication adherence. Mean cholesterol levels decreased over 12 months in both arms (–0.22 mmol/l Primrose vs. –0.39 mmol/l TAU). There was a significant reduction in the cost of inpatient mental health attendances (–£799, 95% CI –£1480 to –£117) and total health-care costs (–£895, 95% CI –£1631 to –£160; p = 0.012) in the intervention group, but no significant difference in QALYs (–0.011, 95% CI –0.034 to 0.011). A total of 69% of patients attended two or more Primrose appointments. Audiotapes revealed moderate fidelity to intervention delivery (67.7%). Statin prescribing and adherence was rarely addressed.

Limitations

RCT participants and practices may not represent all UK practices. CVD care in the TAU arm may have been enhanced by trial procedures involving CVD risk screening and feedback.

Conclusions

SMI-specific CVD risk scores better predict new CVD if used to guide statin prescribing in SMI. Statins are effective in reducing levels of cholesterol in people with SMI in UK clinical practice. This primary care RCT evaluated an evidence-based practitioner-led intervention that was well attended by patients and intervention components were delivered. No superiority was shown for the new intervention over TAU for level of cholesterol, but cholesterol levels decreased over 12 months in both arms and the intervention showed fewer inpatient admissions. There was no difference in cholesterol levels between the intervention and TAU arms, which might reflect better than standard general practice care in TAU, heterogeneity in intervention delivery or suboptimal emphasis on statins.

Future work

The new risk score should be updated, deployed and tested in different settings and compared with the latest versions of CVD risk scores in different countries. Future research on CVD risk interventions should emphasise statin prescriptions more. The mechanism behind lower costs with the Primrose intervention needs exploring, including SMI-related training and offering frequent support to people with SMI in primary care.

Trial registration

Current Controlled Trials ISRCTN13762819.

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 7, No. 2. See the NIHR Journals Library website for further project information. Professor David Osborn is supported by the University College London Hospital NIHR Biomedical Research Centre and he was also in part supported by the NIHR Collaboration for Leadership in Applied Health Research and Care (CLAHRC) North Thames at Barts Health NHS Trust.

Schizophrenia in type 2 diabetes mellitus: Prevalence and clinical characteristics

BACKGROUND

This study investigated the prevalence and characteristics of schizophrenia in patients with type 2 diabetes mellitus (T2DM) in Taiwan.

METHODS

National Health Insurance claims data for patients with principal diagnoses of schizophrenia and T2DM were analysed.

RESULTS

Compared with patients with schizophrenia in the general population (GP), those with schizophrenia and T2DM were more likely to have higher Charlson comorbidity index (CCI) scores and multiple comorbidities, and were older. The prevalence of schizophrenia was significantly higher in patients with T2DM than in the GP from 2000 to 2010. In addition, during this period, the prevalence of schizophrenia in patients with T2DM increased from 0.64% to 0.85%; such an increase in the GP was also observed. A high prevalence of schizophrenia was observed in patients with T2DM aged less than 60 years old; those residing in eastern Taiwan; those with incomes of ≤NT$17,280, NT$17,281-NT$22,880, NT$22,881-NT$28,800, and NT$36,301-NT$45,800; and those with CCI > 2.

CONCLUSIONS

Our study found the prevalence of schizophrenia is higher in patients with T2DM than in the GP, particularly those with earlier ages less than 60 years old. Public health initiatives are necessary to prevent and treat schizophrenia in patients with T2DM, specifically for those with the aforementioned and premature death risk.

The Effectiveness of Pharmacological and Non-Pharmacological Interventions for Improving Glycaemic Control in Adults with Severe Mental Illness: A Systematic Review and Meta-Analysis

People with severe mental illness (SMI) have reduced life expectancy compared with the general population, which can be explained partly by their increased risk of diabetes. We conducted a meta-analysis to determine the clinical effectiveness of pharmacological and non-pharmacological interventions for improving glycaemic control in people with SMI (PROSPERO registration: CRD42015015558). A systematic literature search was performed on 30/10/2015 to identify randomised controlled trials (RCTs) in adults with SMI, with or without a diagnosis of diabetes that measured fasting blood glucose or glycated haemoglobin (HbA_1c). Screening and data extraction were carried out independently by two reviewers. We used random effects meta-analysis to estimate effectiveness, and subgroup analysis and univariate meta-regression to explore heterogeneity. The Cochrane Collaboration’s tool was used to assess risk of bias. We found 54 eligible RCTs in 4,392 adults (40 pharmacological, 13 behavioural, one mixed intervention). Data for meta-analysis were available from 48 RCTs (n = 4052). Both pharmacological (mean difference (MD), -0.11mmol/L; 95% confidence interval (CI), [-0.19, -0.02], p = 0.02, n = 2536) and behavioural interventions (MD, -0.28mmol//L; 95% CI, [-0.43, -0.12], p<0.001, n = 956) were effective in lowering fasting glucose, but not HbA_1c (pharmacological MD, -0.03%; 95% CI, [-0.12, 0.06], p = 0.52, n = 1515; behavioural MD, 0.18%; 95% CI, [-0.07, 0.42], p = 0.16, n = 140) compared with usual care or placebo. In subgroup analysis of pharmacological interventions, metformin and antipsychotic switching strategies improved HbA_1c. Behavioural interventions of longer duration and those including repeated physical activity had greater effects on fasting glucose than those without these characteristics. Baseline levels of fasting glucose explained some of the heterogeneity in behavioural interventions but not in pharmacological interventions. Although the strength of the evidence is limited by inadequate trial design and reporting and significant heterogeneity, there is some evidence that behavioural interventions, antipsychotic switching, and metformin can lead to clinically important improvements in glycaemic measurements in adults with SMI.

Effects of Changing the Amount and Source of Dietary Carbohydrates on Symptoms and Dietary Satisfaction Over a 1-Year Period in Subjects with Type 2 Diabetes: Canadian Trial of Carbohydrates in Diabetes (CCD)

OBJECTIVES

To determine the long-term effects of changing the amount or source of dietary carbohydrate on quality of life (QOL), symptoms and dietary satisfaction in people with type 2 diabetes.

METHODS

Subjects with diabetes treated by diet alone (n=162) were randomly assigned to high-carbohydrate/high-glycemic-index (HGI) diets; high-carbohydrate/low-glycemic-index (LGI) diets; or lower-carbohydrate/high-monounsaturated-fat (LC) diets for 1 year. We measured QOL at baseline and at study's end, and we measured symptoms and dietary satisfaction quarterly.

RESULTS

The HGI, LGI and LC diets contained, respectively, 47±1, 52±1 and 40±1% energy carbohydrate; 30±1, 27±1 and 40±1% fat with GI 64±0.4, 55±0.4 and 59±0.4. Significantly more participants reported increased flatulence on LGI than on LC and HGI diets at 3 months (41%, 19%, 14%; p<0.05), but not at 12 months (29%, 17%, 17%; ns). Abdominal distension was more severe (46% vs. 14%, 19%; p<0.05), and headache less severe (8% vs. 22%, 23%; p<0.05) on LGI than on both other diets. Increased appetite was more severe on LC (33%) than on HGI diets (14%, p<0.05). Joint/limb pains were less severe on LGI (16%) than HGI (28%) diets. LC elicited more severe gloomy thoughts (23%) than LGI (4%; p<0.05) but greater dietary-satisfaction (70%; p<0.05) than LGI (40%) and HGI (48%) diets. For all diets, glycated hemoglobin (A1C) levels increased less in those who gained less weight, had less increased appetite and were more satisfied with the enjoyment obtained from eating.

CONCLUSIONS

Each diet elicited increased severity of 1 or more symptoms than the other diets. Although overall dietary satisfaction was greater on the 40% carbohydrate diet than on the 50% carbohydrate diet, the LGI diet was no less satisfying than the HGI diet. Changes in appetite and dietary satisfaction may influence body weight and glycemic control, or vice-versa.

The effects of pioglitazone adjuvant therapy on negative symptoms of patients with chronic schizophrenia: a double-blind and placebo-controlled trial

OBJECTIVE

The evident central role of inflammation, oxidative stress, and metabolic derangement in pathophysiology of negative symptoms of schizophrenia has opened new insights into probable pharmacological options for these symptoms. Pioglitazone is an antidiabetic agent with anti-inflammatory and antioxidant properties. In this study, we evaluated the efficacy of pioglitazone as an adjunct to risperidone for reduction of negative symptoms in schizophrenia.

METHODS

In this randomized, double-blind, placebo-controlled trial, 40 patients with chronic schizophrenia and a minimum score of 20 on the negative subscale of Positive and Negative Syndrome Scale (PANSS) were randomly allocated to receive risperidone plus either pioglitazone (30 mg/day) or placebo for 8 weeks. Patients' symptoms and adverse events were rated at baseline and weeks 2, 4, 6, and 8. The difference between the two groups in decline of PANSS negative subscale scores was considered as the primary outcome of this study.

RESULTS

At the study endpoint, patients in the pioglitazone group showed significantly more improvement in PANSS negative subscale scores (p < 0.001) as well as PANSS total scores (p = 0.01) compared with the placebo group.

CONCLUSION

These findings suggest the probable efficacy of pioglitazone as an augmentation therapy in reducing the negative symptoms of schizophrenia.

Interventions to Address Medical Conditions and Health-Risk Behaviors Among Persons With Serious Mental Illness: A Comprehensive Review

People with serious mental illness (SMI) have mortality rates 2 to 3 times higher than the overall US population, largely due to cardiovascular disease. The prevalence of cardiovascular risk factors such as obesity and diabetes mellitus and other conditions, such as HIV/AIDS, is heightened in this group. Based on the recommendations of a National Institute of Mental Health stakeholder meeting, we conducted a comprehensive review examining the strength of the evidence surrounding interventions to address major medical conditions and health-risk behaviors among persons with SMI. Peer-reviewed studies were identified using 4 major research databases. Randomized controlled trials and observational studies testing interventions to address medical conditions and risk behaviors among persons with schizophrenia and bipolar disorder between January 2000 and June 2014 were included. Information was abstracted from each study by 2 trained reviewers, who also rated study quality using a standard tool. Following individual study review, the quality of the evidence (high, medium, low) and the effectiveness of various interventions were synthesized. 108 studies were included. The majority of studies examined interventions to address overweight/obesity (n = 80). The strength of the evidence was high for 4 interventions: metformin and behavioral interventions had beneficial effects on weight loss; and bupropion and varenicline reduced tobacco smoking. The strength of the evidence was low for most other interventions reviewed. Future studies should test long-term interventions to cardiovascular risk factors and health-risk behaviors. In addition, future research should study implementation strategies to effectively translate efficacious interventions into real-world settings.

Metformin attenuates olanzapine-induced hepatic, but not peripheral insulin resistance

Antipsychotics (APs) are linked to diabetes, even without weight gain. Whether anti-diabetic drugs are efficacious in reversing the direct effects of APs on glucose pathways is largely undetermined. We tested two metformin (Met) doses to prevent impairments seen following a dose of olanzapine (Ola) (3 mg/kg); glucokinetics were measured using the hyperinsulinemic-euglycemic clamp (HIEC). Met (150 mg/kg; n=13, or 400 mg/kg; n=11) or vehicle (Veh) (n=11) was administered through gavage preceding an overnight fast, followed by a second dose prior to the HIEC. Eleven additional animals were gavaged with Veh and received a Veh injection during the HIEC (Veh/Veh); all others received Ola. Basal glucose was similar across treatment groups. The Met 400 group had significantly greater glucose appearance (Ra) in the basal period (i.e., before Ola, or hyperinsulinemia) vs other groups. During hyperinsulinemia, glucose infusion rate (GINF) to maintain euglycemia (reflective of whole-body insulin sensitivity) was higher in Veh/Veh vs other groups. Met 150/Ola animals demonstrated increased GINF relative to Veh/Ola during early time points of the HIEC. Glucose utilization during hyperinsulinemia, relative to basal conditions, was significantly higher in Veh/Veh vs other groups. The change in hepatic glucose production (HGP) from basal to hyperinsulinemia demonstrated significantly greater decreases in Veh/Veh and Met 150/Ola groups vs Veh/Ola. Given the increase in basal Ra with Met 400, we measured serum lactate (substrate for HGP), finding increased levels in Met 400 vs Veh and Met 150. In conclusion, Met attenuates hepatic insulin resistance observed with acute Ola administration, but fails to improve peripheral insulin resistance. Use of supra-therapeutic doses of Met may mask metabolic benefits by increasing lactate.

Pioglitazone is an effective treatment for patients with post-stroke depression combined with type 2 diabetes mellitus

The antidepressive effects of the antidiabetic medicine, pioglitazone, were recently reported in several studies. These effects may ameliorate the depressive symptoms of patients with post-stroke depression (PSD). The present study aimed to evaluate the antidepressive effect of pioglitazone in patients with PSD combined with type 2 diabetes. A total of 118 consecutive patients with stroke who had depression were studied for an average of 3 months. The Diagnostic and Statistical Manual of Mental Disorders (fourth edition) was used to assess whether a patient was depressed or not. The severity of depression was evaluated by the Hamilton depression rating scale (HAMD). In accordance with their HAMD scores, the 118 patients were divided into a severe depression group (n=40) and a mild and moderate (MM) depression group (n=78). These subjects were then divided into pioglitazone [30 mg once daily (qd)] and metformin (0.5 g twice daily) subgroups. All patients were given fluoxetine (20 mg qd). Follow-up evaluations, which included HAMD scores, activities of daily living (ADL) scores, fasting blood glucose (FBG) levels and fasting insulin (FINS) levels, were conducted on the first and third month following the beginning of the treatment. In the MM depression group, the HAMD score in the pioglitazone subgroup was lower than that in the metformin subgroup following treatment for 1 or 3 months. In the severe depression group, the HAMD score in the pioglitazone subgroup was lower than that in the metformin subgroup following 3 months of treatment. The FINS levels of the pioglitazone subgroup gradually decreased in the 3 months of treatment. No noticeable improvement was observed in the ADL scores and FBG values. In conclusion, the results of the current study demonstrate that pioglitazone effectively decreased HAMD scores and FINS values in patients with PSD, suggesting that pioglitazone may be useful for the treatment of patients with PSD combined with type 2 diabetes.

Clinical management of comorbid diabetes and psychotic disorders

Individuals with psychotic disorders experience substantial health disparities with respect to diabetes, including increased risk of incident diabetes and of poor diabetes outcomes (eg, diabetes complications and mortality). Low-quality medical care for diabetes is a significant contributor to these poor health outcomes. A thoughtful approach to both diabetes pharmacotherapy and drug management for psychotic disorders is essential, irrespective of whether treatment is given by a psychiatrist, a primary care provider, or an endocrinologist. Exposure to drugs with high metabolic liability should be minimised, and both psychiatric providers and medical providers need to monitor patients to ensure that medical care for diabetes is adequate. Promising models of care management and team approaches to coordination and integration of care highlight the crucial need for communication and cooperation among medical and psychiatric providers to improve outcomes in these patients. Evidence-based programmes that promote weight loss or smoking cessation need to be more accessible for these patients, and should be available in all the settings where they access care.