The Complex Inter-Relationship Between Diabetes and Schizophrenia

Hematologic and biochemical inflammatory markers increase with body mass and positively correlate in adolescents

BACKGROUND

Atherosclerosis is a chronic inflammatory disease that has its origins in childhood. The goal of this study was to explore the relationships of hematologic inflammatory markers to body mass, biochemical inflammatory markers and cardiometabolic risk factors.

METHODS

Healthy, white, non-Hispanic identifying adolescents (n = 75, age 12 to 18 years) were enrolled. Measures studied included body mass index percentile (BMI%), neutrophil and platelet to lymphocyte ratio (NLR, PLR), pan immune inflammation value (PIV), lipids, augmentation index, reactive hyperemia, inflammatory markers (interleukin 6: IL6, c-reactive protein: CRP), complement (C3, C3a, C4, C4a, C5a) insulin secretion and insulin sensitivity (oral glucose tolerance test: Matusda index, and disposition index (DI)).

RESULTS

NLR (rS = 0.31, p < 0.01), PLR (rS = 0.32, p < 0.01), PIV (rS = 0.32, p < 0.01) and CRP (rS = 0.51, p < 0.001) all positively correlated with BMI% but IL-6 did not. NLR, PLR and PIV all positively correlated with each other. NLR correlated with the reactive hyperemia response (rS = 0.29, p < 0.02) but this relationship was lost when BMI% was included. NLR positively correlated with C3a, C4, CRP and IL6 even when BMI% was included.

CONCLUSION

In healthy adolescents hematologic markers of inflammation increase with increasing body mass and neutrocyte to lymphocyte ratio is associated with increased complement and inflammatory markers independent of obesity.

IMPACT STATEMENT

Hematologic and biochemical markers of inflammation increase with increased body mass in healthy adolescents. Hematologic and biochemical markers of inflammation are positively related independent of body mass in healthy adolescents. Hematologic inflammatory markers are not related to markers of cardiometabolic risk in healthy adolescents.

Functional Nutrition as Integrated Intervention for In- and Outpatient with Schizophrenia

Schizophrenia is a chronic and progressive disorder characterized by cognitive, emotional, and behavioral abnormalities associated with neuronal development and synaptic plasticity alterations. Genetic and epigenetic abnormalities in cortical parvalbumin-positive GABAergic interneurons and consequent alterations in glutamate-mediated excitatory neurotransmission during early neurodevelopment underlie schizophrenia manifestation and progression. Also, epigenetic alterations during pregnancy or early phases of postnatal life are associated with schizophrenia vulnerability and inflammatory processes, which are at the basis of brain pathology and a higher risk of comorbidities, including cardiovascular diseases and metabolic syndrome. In addition, schizophrenia patients adopt an unhealthy lifestyle and poor nutrition, leading to premature death. Here, I explored the role of functional nutrition as an integrated intervention for the long-term management of patients with schizophrenia. Several natural bioactive compounds in plant-based whole foods, including flavonoids, phytonutrients, vitamins, fatty acids, and minerals, modulate brain functioning by targeting neuroinflammation and improving cognitive decline. Although further clinical studies are needed, a functional diet rich in natural bioactive compounds might be effective in synergism with standard treatments to improve schizophrenia symptoms and reduce the risk of comorbidities.

Prevalence and clinical correlates of impaired glucose tolerance in first-episode versus chronic patients with schizophrenia

AIM

Studies using oral glucose tolerance tests (OGTT) have shown that impaired glucose metabolism presents in the early stages of schizophrenia (SCZ). However, there is a lack of studies on changes in glucose metabolism with the stage of the disease. We first explored the features of glucose metabolic pattern at different phases of male SCZ.

METHODS

We recruited 83 male first episode drug-naïve patients with SCZ (FEDN-SCZ) and 64 male chronic patients with SCZ (CH-SCZ), as well as 14 male healthy controls. The Positive and Negative Syndrome Scale (PANSS) was used to assess the psychopathology of patients. OGTT, fasting plasma glucose and lipid profiles of all participants were examined.

RESULTS

While the impaired glucose tolerance (IGT) rate of male SCZ patients was higher than that of HC (P < .05), there was no difference in IGT prevalence between FEDN-SCZ and CH-SCZ. In male FEDN-SCZ, LDL (OR = 2.64, 95% CI = 1.11-6.29, P = .028) and PANSS total score (OR = 1.03, 95% CI = 1.00-1.06, P = .046) were positively correlated with IGT; in male CH-SCZ, BMI (OR = 1.7, 95% CI = 1.08-2.67, P = .023), PANSS total score (OR = 0.82, 95% CI = 0.70-0.96, P = .015) and positive symptoms (OR = 0.45, 95% CI = 0.20-0.99, P = .046) were significantly correlated with IGT.

CONCLUSIONS

Our findings reflect different glucose metabolism patterns in different stages of SCZ.

Prevalence and clinical characteristics of COVID-19 in inpatients with schizophrenia in Wuhan, China

BACKGROUND

In contrast to many Western countries, China has maintained its large psychiatric hospitals. The prevalence and clinical characteristics of coronavirus disease 2019 (COVID-19) in inpatients with schizophrenia (SCZ) are unclear.

AIM

To assess the prevalence of COVID-19 among inpatients with SCZ and compare the infected to uninfected SCZ patients in a Wuhan psychiatric hospital.

METHODS

We retrospectively collected demographic characteristics and clinical profiles of all SCZ patients with COVID-19 at Wuhan’s Youfu Hospital.

RESULTS

Among the 504 SCZ patients, 84 had COVID-19, and we randomly sampled 174 who were uninfected as a comparison group. The overall prevalence of COVID-19 in SCZ patients was 16.7%. Among the 84 SCZ patients with confirmed COVID-19, the median age was 54 years and 76.2% were male. The most common symptom was fever (82%), and less common symptoms were cough (31%), poor appetite (20%), and fatigue (16%). Compared with SCZ patients without COVID-19, those with COVID-19 were older (P = 0.006) and significantly lighter (P = 0.002), and had more comorbid physical diseases (P = 0.001). Surprisingly, those infected were less likely to be smokers (< 0.001) or to be treated with clozapine (P = 0.03). Further logistic regression showed that smoking [odds ratio (OR) = 5.61], clozapine treated (OR = 2.95), and male (OR = 3.48) patients with relatively fewer comorbid physical diseases (OR = 0.098) were at a lower risk for COVID-19. SCZ patients with COVID-19 presented primarily with fever, but only one-third had a cough, which might otherwise be the most common mode of transmission between individuals.

CONCLUSION

Two unexpected protective factors for COVID-19 among SCZ inpatients are smoking and clozapine treatment.

Metabolic disturbances associated with antipsychotic drug treatment in patients with schizophrenia: State-of-the-art and future perspectives

Metabolic disturbances and obesity are major cardiovascular risk factors in patients with schizophrenia, resulting in a higher mortality rate and shorter life expectancy compared with those in the general population. Although schizophrenia and metabolic disturbances may share certain genetic or pathobiological risks, antipsychotics, particularly those of second generation, may further increase the risk of weight gain and metabolic disturbances in patients with schizophrenia. This review included articles on weight gain and metabolic disturbances related to antipsychotics and their mechanisms, monitoring guidelines, and interventions. Nearly all antipsychotics are associated with weight gain, but the degree of the weight gain varies considerably. Although certain neurotransmitter receptor-binding affinities and hormones are correlated with weight gain and specific metabolic abnormalities, the precise mechanisms underlying antipsychotic-induced weight gain and metabolic disturbances remain unclear. Emerging evidence indicates the role of genetic polymorphisms associated with antipsychotic-induced weight gain and antipsychotic-induced metabolic disturbances. Although many guidelines for screening and monitoring antipsychotic-induced metabolic disturbances have been developed, they are not routinely implemented in clinical care. Numerous studies have also investigated strategies for managing antipsychotic-induced metabolic disturbances. Thus, patients and their caregivers must be educated and motivated to pursue a healthier life through smoking cessation and dietary and physical activity programs. If lifestyle intervention fails, switching to another antipsychotic drug with a lower metabolic risk or adding adjunctive medication to mitigate weight gain should be considered. Antipsychotic medications are essential for schizophrenia treatment, hence clinicians should monitor and manage the resulting weight gain and metabolic disturbances.

Retinal Microvasculature in Schizophrenia

PURPOSE

Schizophrenia is associated with alterations in neural structure and function of the retina that are similar to changes seen in the retina and brain in multiple neurodegenerative disorders. Preliminary evidence suggests that retinal microvasculature may also be compromised in schizophrenia. The goal of this study was to determine, using optical coherence tomography angiography (OCTA), whether 1) schizophrenia is associated with alterations in retinal microvasculature density; and 2) microvasculature reductions are associated with retinal neural layer thinning and performance on a measure of verbal IQ.

PATIENTS AND METHODS

Twenty-eight outpatients with schizophrenia or schizoaffective disorder and 37 psychiatrically healthy control subjects completed OCT and OCTA exams, and the Wechsler Test of Adult Reading.

RESULTS

Schizophrenia patients were characterized by retinal microvasculature density reductions, and enlarged foveal avascular zones, in both eyes. These microvascular abnormalities were generally associated with thinning of retinal neural (macular and peripapillary nerve fiber layer) tissue (but the data were stronger for the left than the right eye) and lower scores on a proxy measure of verbal IQ. First- and later-episode patients did not differ significantly on OCTA findings.

CONCLUSION

The retinal microvasculature impairments seen in schizophrenia appear to be a biomarker of overall brain health, as is the case for multiple neurological conditions. Additional research is needed, however, to clarify contributions of social disadvantage and medical comorbidities to the findings.

Oral glucose tolerance response curve predicts disposition index but not other cardiometabolic risk factors in healthy adolescents

OBJECTIVES

In obese adults the shape of the glucose response curve during an oral glucose tolerance test (OGTT) predicts future type 2 diabetes. Patients with an incessant increase or monophasic curves have increased risk compared to those with biphasic curves. Since type 2 diabetes is associated with increased cardiometabolic risk, we studied whether differences in OGTT response curve are associated with differences in cardiometabolic risk factors in healthy adolescents across a wide body mass index (BMI) range.

METHODS

Sixty-nine (33F/36M), white adolescents (age: 15.2 ± 1.7 years; BMI: 21.5 ± 4.7 kg/m²; mean ± SD) were studied. Risk factors measured included percent body fat, blood pressure, lipids, augmentation index, reactive hyperemia, endothelin 1, plasminogen activator 1, inflammatory markers (interleukin 6, c-reactive protein), insulin secretion, insulin sensitivity (Matusda index), and disposition index (DI).

RESULTS

Thirty-two subjects had biphasic responses; 35 subjects had monophasic responses and two females had incessant increases. Sex did not affect the frequency of responses. Glucose area under the curve during OGTT was greater in those with a mono vs. biphasic curves (p=0.01). Disposition index was markedly lower in subjects with a monophasic curve than in those with a biphasic curve (3.6 [2.3-5.0] vs. 5.8 [3.8-7.6], median [25th, 75th%] p=0.003). Triglyceride to high-density lipoprotein cholesterol (HDL) ratio was higher in subjects with a monophasic curve (p=0.046).

CONCLUSIONS

The decreased disposition index indicates that in healthy adolescents a monophasic response to OGTT is due to decreased insulin secretion relative to the degree of insulin resistance present. This was not associated with differences in most other cardiometabolic risk markers.

TRIAL REGISTRATION

Clinical Trials.gov, NCT02821104.

Quality of diabetes care in patients with schizophrenia: a case-control study in Qatar

BACKGROUND

Patients with schizophrenia are at least twice as likely to develop diabetes mellitus compared to the general population. This is of significance in Qatar given the high prevalence of obesity and diabetes. Furthermore, the lifespan of people with schizophrenia is shortened by approximately 15 years, partly due to long-term microvascular and macrovascular complications. High quality diabetes care can significantly reduce morbidity and mortality. We assessed the level of diabetes care delivered to patients in Qatar with schizophrenia and diabetes compared to those with diabetes alone.

METHODS

We performed a retrospective chart review of patients with diabetes mellitus with (n = 73) and without (n = 73) schizophrenia. Demographic information and electronic medical records were reviewed to determine adherence to American Diabetes Association standards of diabetes care in the last 6 and 12 months. Optimal diabetes care was defined as having completed glycated hemoglobin (HbA1c), lipid profile and retinal examination within 12 months.

RESULTS

Optimal diabetes care was significantly lower in patients with schizophrenia and diabetes compared to diabetes alone [26.0% (n = 19/73) vs 52.1% (n = 38/73), p = 0.002]. Patients with diabetes and schizophrenia were also significantly less likely to have had body mass index recorded within 6 months (p = 0.008) and HbA1c (p = 0.006), lipid profile (p = 0.015), estimated glomerular filtration rate (eGFR) (p = 0.001) and order for retinal examination (p = 0.004) over 12 months. After adjusting for multiple comparisons, only assessment of eGFR (p = 0.01) and order for retinal examination (p = 0.04) remained significant.

CONCLUSION

Patients in Qatar with schizophrenia and diabetes, receive sub-optimal diabetes care compared to those with diabetes alone.

Association between mental health comorbidity and health outcomes in type 2 diabetes mellitus patients

Type 2 diabetes mellitus (T2D) is often accompanied by chronic diseases, including mental health problems. We aimed at studying mental health comorbidity prevalence in T2D patients and its association with T2D outcomes through a retrospective, observational study of individuals of the EpiChron Cohort (Aragón, Spain) with prevalent T2D in 2011 (n = 63,365). Participants were categorized as having or not mental health comorbidity (i.e., depression, anxiety, schizophrenia, and/or substance use disorder). We performed logistic regression models, controlled for age, sex and comorbidities, to analyse the likelihood of 4-year mortality, 1-year all-cause hospitalization, T2D-hospitalization, and emergency room visit. Mental health comorbidity was observed in 19% of patients. Depression was the most frequent condition, especially in women (20.7% vs. 7.57%). Mortality risk was higher in patients with mental health comorbidity (odds ratio 1.24; 95% confidence interval 1.16-1.31), especially in those with substance use disorder (2.18; 1.84-2.57) and schizophrenia (1.82; 1.50-2.21). Mental health comorbidity also increased the likelihood of all-cause hospitalization (1.16; 1.10-1.23), T2D-hospitalization (1.51; 1.18-1.93) and emergency room visit (1.26; 1.21-1.32). These results suggest that T2D healthcare management should include specific strategies for the early detection and treatment of mental health problems to reduce its impact on health outcomes.

Use of skin advanced glycation end product levels measured using a simple noninvasive method as a biological marker for the diagnosis of neuropsychiatric diseases

OBJECTIVES

The accumulation of advanced glycation end products (AGEs) may be involved in the pathophysiology of several neuropsychiatric diseases. In this study, the skin AGEs level of several neuropsychiatric diseases was assessed with a simple noninvasive method. Moreover, whether skin AGE level can be used as a biomarker for the diagnosis of these diseases was evaluated.

METHODS

A total of 27 patients with schizophrenia, 26 with major depressive disorder, and 10 with major neurocognitive disorders (MNDs), such as Alzheimer's disease or dementia with Lewy body, as well as 26 healthy controls were enrolled in this study. The skin AGE levels of the patients were assessed with an AGE scanner, a fluorometric method used to assay skin AGE levels.

RESULTS

One-way analysis of covariance was performed after adjusting for significant covariates, including age. Although the group with MNDs had higher skin AGE levels than the other groups, the main effect of diagnosis did not significantly affect the skin AGE levels of the groups.

CONCLUSIONS

Skin AGE levels in neuropsychiatric diseases with mild symptoms did not significantly differ. Further large-scale studies using a simple noninvasive method for the early detection and treatment of MNDs must be conducted.

Schizophrenia and the retina: Towards a 2020 perspective

BACKGROUND

Differences between people with schizophrenia and psychiatrically healthy controls have been consistently demonstrated on measures of retinal function such as electroretinography (ERG), and measures of retinal structure such as optical coherence tomography (OCT). Since our 2015 review of this literature, multiple new studies have been published using these techniques. At the same time, the accumulation of data has highlighted the "fault lines" in these fields, suggesting methodological considerations that need greater attention in future studies.

METHODS

We reviewed studies of ERG and OCT in schizophrenia, as well as data from studies whose findings are relevant to interpreting these papers, such as those on effects of the following on ERG and OCT data: comorbid medical conditions that are over-represented in schizophrenia, smoking, antipsychotic medication, substance abuse, sex and gender, obesity, attention, motivation, and influences of brain activity on retinal function.

RESULTS

Recent ERG and OCT studies continue to support the hypothesis of retinal structural and functional abnormalities in schizophrenia, and suggest that these are relevant to understanding broader aspects of pathophysiology, neurodevelopment, and neurodegeneration in this disorder. However, there are differences in findings which suggest that the effects of multiple variables on ERG and OCT data need further clarification.

CONCLUSIONS

The retina, as the only component of the CNS that can be imaged directly in live humans, has potential to clarify important aspects of schizophrenia. With greater attention to specific methodological issues, the true potential of ERG and OCT as biomarkers for important clinical phenomena in schizophrenia should become apparent.

Relationships of complement components C3 and C4 and their genetics to cardiometabolic risk in healthy, non-Hispanic white adolescents

BACKGROUND

Complement promotes inflammatory and immune responses and may affect cardiometabolic risk. This study was designed to investigate the effect of complement components C3 and C4 on cardiometabolic risk in healthy non-Hispanic white adolescents.

METHODS

Body mass index (BMI), BMI percentile, waist circumference, and percent body fat were assessed in 75 adolescents. Arterial stiffness was assessed using arterial tomography and endothelial function using reactive hyperemia. Fasting lipids, inflammatory markers, and complement levels were measured and oral glucose tolerance test was performed. A single C3 polymorphism and C4 gene copy number variations were assessed.

RESULTS

C3 plasma levels increased with measures of obesity. Endothelial function worsened with increased C3 and C4 levels. Triglycerides and low-density lipoprotein increased and high-density lipoprotein (HDL) and insulin sensitivity decreased with increasing C3 levels, but the relationships were lost when body habitus was included in the model. C4 negatively related to HDL and positively to inflammatory markers. Subjects with at least one C3F allele had increased BMI and fat mass index. HDL was significantly related to C4L, C4S, C4A, and C4B gene copy number variation.

CONCLUSIONS

C3 levels increase with increasing body mass and increased C4 levels and copy number are associated with increased cardiometabolic risk in healthy adolescents.

Cortisol and DHEAS Related to Metabolic Syndrome in Patients with Schizophrenia

BACKGROUND

Both dehydroepiandrosterone (DHEAS) and cortisol are secreted by the adrenal glands and may modulate metabolic syndrome (MetS), which often affects the health of patients with schizophrenia. The relationship between the serum levels of these hormones and MetS has not been established.

PURPOSE

In this pilot study, we investigated the serum levels in schizophrenia patients with and without MetS and compared them with those in healthy volunteers.

PATIENTS AND METHODS

After obtaining informed consent, 110 patients with acute paranoid schizophrenia were recruited directly after admission to the Mental Health Research Institute. The control group consisted of 51 persons reported on questioning to be mentally and somatically healthy. Blood samples to prepare serum were drawn after an 8-h overnight fast during one of the first days of admission. Serum cortisol and DHEAS concentrations were quantified by enzyme-linked immunosorbent assay.

RESULTS

A total of 42 patients had MetS and 68 patients were without MetS. The cortisol blood level was significantly (p = 0.012) higher in schizophrenia patients without MetS in comparison to healthy controls, while patients with schizophrenia and a MetS have significantly (p = 0.014) lower DHEAS levels than healthy volunteers. These differences could, however, exclusively be attributed to female participants. Analysis of covariance adjusted for gender and age demonstrated a significant relationship between age and DHEAS levels (F = 9.512, р = 0.003).

CONCLUSION

Lower DHEAS serum levels in relationship to MetS become evident in women, but not in men, and have age differences as a confounding factor.

Revealing the Interactions Between Diabetes, Diabetes-Related Diseases, and Cancers Based on the Network Connectivity of Their Related Genes

Diabetes-related diseases (DRDs), especially cancers pose a big threat to public health. Although people have explored pathological pathways of a few common DRDs, there is a lack of systematic studies on important biological processes (BPs) connecting diabetes and its related diseases/cancers. We have proposed and compared 10 protein-protein interaction (PPI)-based computational methods to study the connections between diabetes and 254 diseases, among which a method called DIconnectivity_eDMN performs the best in the sense that it infers a disease rank (according to its relation with diabetes) most consistent with that by literature mining. DIconnectivity_eDMN takes diabetes-related genes, other disease-related genes, a PPI network, and genes in BPs as input. It first maps genes in a BP into the PPI network to construct a BP-related subnetwork, which is expanded (in the whole PPI network) by a random walk with restart (RWR) process to generate a so-called expanded modularized network (eMN). Since the numbers of known disease genes are not high, an RWR process is also performed to generate an expanded disease-related gene list. For each eMN and disease, the expanded diabetes-related genes and disease-related genes are mapped onto the eMN. The association between diabetes and the disease is measured by the reachability of their genes on all eMNs, in which the reachability is estimated by a method similar to the Kolmogorov-Smirnov (KS) test. DIconnectivity_eDMN achieves an area under receiver operating characteristic curve (AUC) of 0.71 for predicting both Type 1 DRDs and Type 2 DRDs. In addition, DIconnectivity_eDMN reveals important BPs connecting diabetes and DRDs. For example, "respiratory system development" and "regulation of mRNA metabolic process" are critical in associating Type 1 diabetes (T1D) and many Type 1 DRDs. It is also found that the average proportion of diabetes-related genes interacting with DRDs is higher than that of non-DRDs.

VGF has Roles in the Pathogenesis of Major Depressive Disorder and Schizophrenia: Evidence from Transgenic Mouse Models

Mental disorders, such as major depressive disorder and schizophrenia, are complex multigenetic conditions, but focused studies of single genes might reveal genes involved in the pathogenesis of mental disorders, including major depressive disorder and schizophrenia. Several candidate genes have been identified using transgenic mice. VGF nerve growth factor inducible (VGF) is a neuropeptide expression of which is induced by nerve growth factor (NGF). VGF is robustly and exclusively synthesized in neuronal and neuroendocrine cells. In central nervous system (CNS), VGF is extensively expressed especially in the cerebral cortex, hippocampus, and hypothalamus. VGF has many roles in the CNS, such as promotion of synaptic plasticity, neurogenesis, and neurite outgrowth. In clinical studies, altered expression and genetic mutations of VGF have been reported in patients with major depressive disorder and schizophrenia. On this basis, studies using transgenic mice to overexpress or knockout VGF have been performed to investigate the roles of upregulation or downregulation of VGF. In this review, we will discuss studies of the roles of VGF using transgenic mice and its relevance to pathologies in major depressive disorder and schizophrenia.

Cancer and the Dopamine D2 Receptor: A Pharmacological Perspective

The dopamine D₂ receptor (D₂R) family is upregulated in many cancers and tied to stemness. Reduced cancer risk has been correlated with disorders such as schizophrenia and Parkinson's disease, in which dopaminergic drugs are used. D₂R antagonists are reported to have anticancer efficacy in cell culture and animal models where they have reduced tumor growth, induced autophagy, affected lipid metabolism, and caused apoptosis, among other effects. This has led to several hypotheses, the most prevalent being that D₂R ligands may be a novel approach to cancer chemotherapy. This hypothesis is appealing because of the large number of approved and experimental drugs of this class that could be repurposed. We review the current state of the literature and the evidence for and against this hypothesis. When the existing literature is evaluated from a pharmacological context, one of the striking findings is that the concentrations needed for cytotoxic effects of D₂R antagonists are orders of magnitude higher than their affinity for this receptor. Although additional definitive studies will provide further clarity, our hypothesis is that targeting D₂-like dopamine receptors may only yield useful ligands for cancer chemotherapy in rare cases.