Neurophysiological correlates of metabolic syndrome and cognitive impairment in schizophrenia: a structural equation modeling approach

Neuroinflammation and kynurenines in schizophrenia: Impact on cognition depending on cognitive functioning and modulatory properties in relation to cognitive remediation and aerobic exercise

Background

In the last decade, the kynurenine pathway (KP) has gained attention in the pathogenesis of cognitive impairment in schizophrenia being at the croassroad between neuroinflammation and glutamatergic and cholinergic neurotransmission. However, clinical findings are scarse and conflicting, and the specific contributions of these two systems to the neurobiology of cognitive symptoms are far from being elucidated. Furthermore, little is known about the molecular underpinnings of non-pharmacological interventions for cognitive improvement, including rehabilitation strategies.

Methods

The current study examined 72 patients with schizophrenia, divided in two clusters depending on the severity of the cognitive impairment, with the aim to evaluate the impact of inflammatory biomarkers and KP metabolites depending on cognitive functioning. Moreover, we studied their possible link to the cognitive outcome in relation to sessions of cognitive remediation therapy (CRT) and aerobic exercise (AE) in a longitudinal arm of 42 patients.

Results

Neuroinflammation appeared to exert a more pronounced influence on cognition in patients exhibiting a higher cognitive functioning, contrasting with the activation of the KP, which had a greater impact on individuals with a lower cognitive profile. Cognitive improvements after the treatments were negatively predicted by levels of TNF-α and positively predicted by the 3-hydroxykynurenine (3-HK)/kynurenine (KYN) ratio, an index of the kynurenine-3-monooxygenase (KMO) enzyme activity.

Conclusion

Overall, these findings add novel evidence on the biological underpinnings of cognitive impairment in schizophrenia pointing at a differential role of neuroinflammation and KP metabolites in inducing cognitive deficits depending on the cognitive reserve and predicting outcomes after rehabilitation.

Metabolic disturbances, hemoglobin A1c, and social cognition impairment in Schizophrenia spectrum disorders

Social cognitive impairments are core features of schizophrenia spectrum disorders (SSD) and are associated with greater functional impairment and decreased quality of life. Metabolic disturbances have been related to greater impairment in general neurocognition, but their relationship to social cognition has not been previously reported. In this study, metabolic measures and social cognition were assessed in 245 participants with SSD and 165 healthy comparison subjects (HC), excluding those with hemoglobin A1c (HbA1c) > 6.5%. Tasks assessed emotion processing, theory of mind, and social perception. Functional connectivity within and between social cognitive networks was measured during a naturalistic social task. Among SSD, a significant inverse relationship was found between social cognition and cumulative metabolic burden (β = -0.38, p < 0.001) and HbA1c (β = -0.37, p < 0.001). The relationship between social cognition and HbA1c was robust across domains and measures of social cognition and after accounting for age, sex, race, non-social neurocognition, hospitalization, and treatment with different antipsychotic medications. Negative connectivity between affect sharing and motor resonance networks was a partial mediator of this relationship across SSD and HC groups (β = -0.05, p = 0.008). There was a group x HbA1c effect indicating that SSD participants were more adversely affected by increasing HbA1c. Thus, we provide the first report of a robust relationship in SSD between social cognition and abnormal glucose metabolism. If replicated and found to be causal, insulin sensitivity and blood glucose may present as promising targets for improving social cognition, functional outcomes, and quality of life in SSD.

Previous exposure to antipsychotic drug treatment is an effective predictor of metabolic disturbances experienced with current antipsychotic drug treatments

BACKGROUND

Antipsychotic drugs are associated with adverse events, but serious side effects are not frequent. This study aimed to ascertain whether previous exposure to antipsychotic treatment was associated with metabolic disturbances induced by current antipsychotic medication.

METHODS

A total of 115 antipsychotic-naïve patients, 65 patients with previous exposure to low-metabolic-risk antipsychotics, and 88 patients with previous exposure to high-metabolic-risk antipsychotics were enrolled in our case-control study. All patients were administered olanzapine. Body weight, body mass index (BMI), biochemical indicators of blood glucose and lipids, the proportion of patients who gained more than 7% of their body weight at baseline, and the percentage of dyslipidemia were evaluated. All assessments were conducted at baseline and at 4 and 6 weeks after treatment.

RESULTS

Olanzapine treatment resulted in a significant increase in body weight and BMI in antipsychotic-naïve patients compared with the other two groups (both p < 0.05). However, increases in lipid levels in the high-metabolic-risk antipsychotics group were significantly higher than that in the other two groups (both p < 0.05). A history of antipsychotics use was not associated with weight gain (all p > 0.05). Higher low-density lipoprotein cholesterol ≥3.37 mmol/L^-1 was observed in antipsychotics exposure group compared with no history of antipsychotics exposure (aOR, 1.75; 95% CI, 1.07-3.52). Particularly, a history of high-metabolic-risk antipsychotics use was associated with a higher risk of LDL-C ≥3.37 mmol/L-1(aOR, 2.18; 95% CI, 1.03-3.32) compare with other two groups.

CONCLUSIONS

A history of exposure to antipsychotics, particularly high-metabolic-risk antipsychotics, is associated with current antipsychotic-induced metabolic disturbances.

The Predictive Role of Aberrant Metabolic Parameters and Negative Automatic Thinking on the Cognitive Impairments Among Schizophrenia Patients with Metabolic Syndrome

PURPOSE

The study aimed to clarify the cognitive impairments of schizophrenia with metabolic syndrome while evaluating their potential as risk factors.

PATIENTS AND METHODS

We recruited 153 participants and divided them into three groups according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, criteria and the guideline standards for the prevention and treatment of dyslipidemia in Chinese adults in 2007 for metabolic syndrome, as follows: healthy control group (n = 47); nonmetabolic syndrome group (n = 58); and metabolic syndrome group (n = 48). Psychotic symptoms were evaluated using the Positive and Negative Syndrome Scale. Cognitive function and automatic thinking were estimated using the Montreal Cognitive Assessment Scale, Verbal Fluency Test, and Automatic Thoughts Questionnaire. Serum biochemical parameters were measured by automatic biochemistry analyzer.

RESULTS

One-way ANOVA analysis revealed that differential cognition impairments in schizophrenia patients compared to controls. Furthermore, results of multiple comparisons showed that more serious barriers in orientation, language fluency, and negative automatic thinking existed in the metabolic syndrome group than in the healthy and non-metabolic syndrome groups. Spearman correlation and stepwise linear regression analyses showed that psychopathological symptoms, high waist circumference, and high triglyceride were the predictive factors for negative automatic thoughts, orientation, and language fluency. Those results collectively revealed that high waist circumference, high triglyceride and negative automatic thinking had validity and effectiveness in predicting the cognitive function impairments of the metabolic syndrome group.

CONCLUSION

The present findings strongly supported the notion that aberrant parameters of high waist circumference, high triglyceride and high negative automatic thoughts had validity and effectiveness predictive role for cognitive impairments in the schizophrenics with metabolic syndrome. The schizophrenia patients with metabolic syndrome should receive regular monitoring and adequate treatment for metabolic and psychological risk factors.

Association Between Cardiovascular Risk Factors and Cognitive Impairment in People With Schizophrenia: A Systematic Review and Meta-analysis

IMPORTANCE

Schizophrenia is associated with cognitive dysfunction and cardiovascular risk factors, including metabolic syndrome (MetS) and its constituent criteria. Cognitive dysfunction and cardiovascular risk factors can worsen cognition in the general population and may contribute to cognitive impairment in schizophrenia.

OBJECTIVE

To study the association between cognitive dysfunction and cardiovascular risk factors and cognitive impairment in individuals with schizophrenia.

DATA SOURCES

A search was conducted of Embase, Scopus, MEDLINE, PubMed, and Cochrane databases from inception to February 25, 2020, using terms that included synonyms of schizophrenia AND metabolic adversities AND cognitive function. Conference proceedings, clinical trial registries, and reference lists of relevant publications were also searched.

STUDY SELECTION

Studies were included that (1) examined cognitive functioning in patients with schizophrenia or schizoaffective disorder; (2) investigated the association of cardiovascular disease risk factors, including MetS, diabetes, obesity, overweight, obesity or overweight, hypertension, dyslipidemia, and insulin resistance with outcomes; and (3) compared cognitive performance of patients with schizophrenia/schizoaffective disorder between those with vs without cardiovascular disease risk factors.

DATA EXTRACTION AND SYNTHESIS

Extraction of data was conducted by 2 to 3 independent reviewers per article. Data were meta-analyzed using a random-effects model.

MAIN OUTCOMES AND MEASURES

The primary outcome was global cognition, defined as a test score using clinically validated measures of overall cognitive functioning.

RESULTS

Twenty-seven studies involving 10 174 individuals with schizophrenia were included. Significantly greater global cognitive deficits were present in patients with schizophrenia who had MetS (13 studies; n = 2800; effect size [ES] = 0.31; 95% CI, 0.13-0.50; P = .001), diabetes (8 studies; n = 2976; ES = 0.32; 95% CI, 0.23-0.42; P < .001), or hypertension (5 studies; n = 1899; ES = 0.21; 95% CI, 0.11-0.31; P < .001); nonsignificantly greater deficits were present in patients with obesity (8 studies; n = 2779; P = .20), overweight (8 studies; n = 2825; P = .41), and insulin resistance (1 study; n = 193; P = .18). Worse performance in specific cognitive domains was associated with cognitive dysfunction and cardiovascular risk factors regarding 5 domains in patients with diabetes (ES range, 0.23 [95% CI, 0.12-0.33] to 0.40 [95% CI, 0.20-0.61]) and 4 domains with MetS (ES range, 0.15 [95% CI, 0.03-0.28] to 0.40 [95% CI, 0.20-0.61]) and hypertension (ES range, 0.15 [95% CI, 0.04-0.26] to 0.27 [95% CI, 0.15-0.39]).

CONCLUSIONS AND RELEVANCE

In this systematic review and meta-analysis, MetS, diabetes, and hypertension were significantly associated with global cognitive impairment in people with schizophrenia.

The correlation between metabolic syndrome and neurocognitive and social cognitive performance of patients with schizophrenia

Cognitive impairment is one of the core symptoms of schizophrenia, and patients with schizophrenia are at increased risk of metabolic syndrome (MS). However, the role of MS in cognitive impairment of schizophrenia is not established. This study investigated the correlation between neurocognitive, social cognitive performance and MS with schizophrenia. One hundred and fifty eight (158) schizophrenia patients were divided into 3 groups with ① normal metabolism, ② metabolic disorder (only meeting 1 or 2 MS criteria), and ③ metabolic syndrome (meeting 3 or more MS criteria). MATRICS Consensus Cognitive Battery)MCCB(and the Brief Psychiatric Rating Scale)BPRS(were used to evaluate cognitive performance and clinical symptoms. Blood samples were obtained to detect glucose and lipid metabolic levels. Overall MCCB and subscale T scores in the normal metabolism and metabolic disorder groups were better than in the MS group. After controlling for the confounding factors including age, sex, the usage of hypolipidemic and hypoglycemic drugs, and disease duration, metabolic deficits had effects on the symbol coding and spatial span scores. The results suggest that a defective metabolic state might play a role in neurocognitive performance of schizophrenia patients.

Dietary Behaviors and Metabolic Syndrome in Schizophrenia Patients

The metabolic syndrome (MS) is highly prevalent in schizophrenia patients, resulting from both pharmacotherapy and their lifestyle. To avoid its development, the analysis of patients' eating behaviors followed by the necessary nutritional changes should become a routine element of treatment. The aim of this study is to investigate the effect of dietary habits on the course of schizophrenia and MS, cognitive performance, symptom severity, and subjective assessment of eating behaviors in schizophrenia patients. Total of 87 participants (63.2% women) aged 19 to 67 years (M = 41.67; SD = 12.87), of whom 60 met the IDF criteria for MS, completed the PANSS, the verbal fluency test, the Stroop Color-Word Test, and the digit span task, followed by a thorough nutritional interview. There were no significant differences in the dietary behaviors between investigated schizophrenia patients with and without comorbid MS. Interestingly, their eating habits compared quite favorably to those described in the literature. No associations were found between positive eating habits and other tested variables in patients with MS. They were, however, linked to lower PANSS scores in the entire sample. In addition, positive eating habits correlated with better cognitive performance and a more adequate subjective assessment of dietary habits. It would be amiss to assume that schizophrenia patients lack the ability to control their eating behaviors. Nutrition education may foster desirable dietary changes and improve the sense of agency, thus helping to reduce symptom severity and enhancing cognitive performance in this patient population.

Metabolic Syndrome and Cognitive Functions in Schizophrenia-Implementation of Dietary Intervention

INTRODUCTION

The co-existence of schizophrenia and metabolic syndrome is a widely described phenomenon that contributes to the worse functioning of patients in everyday life. A relatively new area of research is the relationship between metabolic syndrome (MS) and cognitive function in patients with schizophrenia. The aim of the study was to verify the relationship between the presence of metabolic syndrome and cognitive function of patients with schizophrenia and to assess the possibility of changing cognitive function by introducing appropriate dietary intervention.

MATERIALS AND METHODS

The study involved 87 individuals diagnosed with schizophrenia according to ICD-10 criteria, aged 19 to 67 years (M = 41.67; SD = 11.87). Patients were in the remission phase of schizophrenia, all using antipsychotics for pharmacological treatment. From a group of 83 patients with schizophrenia and diagnosed metabolic syndrome (according to IDF criteria) 30 patients were randomly assigned to an experimental group-with dietary intervention, 29 patients-to group without dietary intervention, 24 patients with schizophrenia without metabolic syndrome was a comparison group. All groups were evaluated for cognitive function using Stroop Test, Trail Making Test (TMT), Verbal Fluency Test, Digit Span Backwards Test. In the experimental group a dietary intervention was applied, which was to provide the examined person with a 7-day dietary plan with reduced calorie content, in compliance with the Mediterranean diet.

RESULTS

After the dietary intervention there was a significant improvement in the number of errors made in the third Stroop Test (p <0.001), the time taken to complete the Point Linking Test was shortened (Test B; p = 0.005), there was an improvement in Verbal Fluency Test in "animals" category (p = 0.006) "sharp objects" category (p = 0.009), the number of repeated digits has increased in Digit Span Test in "forward" category (p = 0.001) and overall completion of the test (p = 0.021). In the group of patients with MS without dietary intervention, the results of cognitive tests remained mostly unchanged.

CONCLUSIONS

Change of eating habits may be a significant element of a holistic approach to the problems of treatment of schizophrenia.

Test-Retest Reliability and Minimal Detectable Change of the D2 Test of Attention in Patients with Schizophrenia

Objective

The d2 Test of Attention (D2) is a commonly used measure of selective attention for patients with schizophrenia. However, its test-retest reliability and minimal detectable change (MDC) are unknown in patients with schizophrenia, limiting its utility in both clinical and research settings. The aim of the present study was to examine the test-retest reliability and MDC of the D2 in patients with schizophrenia.

Method

A rater administered the D2 on 108 patients with schizophrenia twice at a 1-month interval. Test-retest reliability was determined through the calculation of the intra-class correlation coefficient (ICC). We also carried out Bland-Altman analysis, which included a scatter plot of the differences between test and retest against their mean. Systematic biases were evaluated by use of a paired t-test.

Results

The ICCs for the D2 ranged from 0.78 to 0.94. The MDCs (MDC%) of the seven subscores were 102.3 (29.7), 19.4 (85.0), 7.2 (94.6), 21.0 (69.0), 104.0 (33.1), 105.0 (35.8), and 7.8 (47.8), which represented limited-to-acceptable random measurement error. Trends in the Bland-Altman plots of the omissions (E1), commissions (E2), and errors (E) were noted, presenting that the data had heteroscedasticity.

Conclusions

According to the results, the D2 had good test-retest reliability, especially in the scores of TN, TN-E, and CP. For the further research, finding a way to improve the administration procedure to reduce random measurement error would be important for the E1, E2, E, and FR subscores.

Reward-related brain structures are smaller in patients with schizophrenia and comorbid metabolic syndrome

OBJECTIVE

Metabolic syndrome (MS) is highly prevalent in schizophrenia and often a consequence of unhealthy behaviour. Reward-related brain areas might be associated with MS, since they play a major role in regulating health behaviour. This study examined the relationship between MS and brain volumes related to the reward system in schizophrenia.

METHOD

We included patients with schizophrenia, with MS (MS+; n = 23), patients with schizophrenia, without MS (MS-; n = 48), and healthy controls (n = 54). Global brain volumes and volumes of (sub)cortical areas, part of the reward circuit, were compared between patients and controls. In case of a significant brain volume difference between patients and controls, the impact of MS in schizophrenia was examined.

RESULTS

Patients had smaller total brain (TB; P = 0.001), GM (P = 0.010), larger ventricles (P = 0.026), and smaller reward circuit volume (P < 0.001) than controls. MS+ had smaller TB (P = 0.017), GM (P = 0.008), larger ventricles (P = 0.015), and smaller reward circuit volume (P = 0.002) than MS-. MS+ had smaller orbitofrontal cortex (OFC; P = 0.002) and insula volumes (P = 0.005) and smaller OFC (P = 0.008) and insula cortical surface area (P = 0.025) compared to MS-.

CONCLUSION

In schizophrenia, structural brain volume reductions in areas of the reward circuitry appear to be related to comorbid MS.

Cognitive and functional deficits in people with schizophrenia: Evidence for accelerated or exaggerated aging?

Cognitive and functional deficits are commonly seen in people with schizophrenia. The profile of these impairments has a resemblance to the cognitive changes seen in healthy aging. In specific, many of the cognitive ability domains that change the most with aging in healthy people are the most salient of these deficits seen in people with schizophrenia, including prominent deficits in processing speed, working memory, and episodic memory. Functional deficits seen in schizophrenia are also similar to those seen in healthy aging. There is a relationship between multiple psychotic relapses and treatment resistance and longitudinal cognitive and functional changes in schizophrenia, with this relationship starting early in the course of illness. Cognitive performance in people with schizophrenia may be consistent with accelerated or premature aging. People with schizophrenia perform similarly to healthy people who are 3 or more decades older on indices of both cognition and their everyday functional skills. Some people with schizophrenia show exaggerated cognitive changes as well. Cognitive and functional performance worsens at the outset of the illness in schizophrenia compared to premorbid functioning, meaning that these deficits are not due to development disabilities. There are multiple medical and substance abuse comorbidities in schizophrenia and although these comorbidities affect cognitive functioning, they are not completely responsible for age-related changes.

Analyzing the neuropsychological characteristics and changes in serum markers of patients with chronic cerebral circulation insufficiency

OBJECTIVE

To investigate the neuropsychological characteristics and changes in CRP, S100B, MBP, HSP-7, and NSE in serum.

METHOD

Sixty-six (66) patients treated in our hospital as CCCI group were chosen for our study, and 90 patients with depression were selected as the depression group. The patients in both groups were examined with CT perfusion, depression, anxiety and cognition evaluation. Their serum CRP, S100B, MBP, HSP-70 and NSE levels were detected. Neuropsychological and serum markers characteristics were compared.

RESULTS

The CBF and CBV in bilateral basal ganglia, frontal lobes, greater oval center, brain stem, and left and right regions of occipital lobes of the patients in CCCI group were significantly lower than in the depression group. The HAMD and HAMA scores of CCCI group patients were significantly lower than in the depression group; CCCI group performed better regarding attention, memory, abstract terms and delayed recall. CCCI also had significantly higher total scores than the depression group. Serum CRP, S100B, MBP, HSP-70 and NSE levels in CCCI group were significantly higher than in the depression group. The differences reach statistical significance (p<0.05).

CONCLUSION

CCCI patients who are accompanied by minor depressive disorder have different degrees of cognitive impairment and experience a significant rise in serum CRP, S100B, MBP, HSP-70 and NSE.

The relationship between cognitive impairment in schizophrenia and metabolic syndrome: a systematic review and meta-analysis

BACKGROUND

Individuals with schizophrenia are at greater risk for metabolic syndrome (MetS) which is associated with cognitive deficits in the general population. MetS might be potentially an important contributing factor to cognitive impairment in schizophrenia.

METHOD

In the current systematic review and meta-analysis, the findings of 18 studies investigating the association between MetS (and its components) with cognitive impairment in schizophrenia are reviewed.

RESULTS

Co-morbidity of MetS (d = 0.28) and diabetes mellitus (d = 0.28) were both associated with more severe cognitive deficits in schizophrenia. There was also evidence for a significant relationship between cognitive impairment in schizophrenia and each of the components of MetS including hypertension, dyslipidemia, abdominal obesity and diabetes.

CONCLUSIONS

MetS is significantly associated with cognitive impairment in schizophrenia and can potentially contribute to functional decline observed in some patients with schizophrenia throughout the course of illness.

Neurovascular Unit Dysfunction and Blood-Brain Barrier Hyperpermeability Contribute to Schizophrenia Neurobiology: A Theoretical Integration of Clinical and Experimental Evidence

Schizophrenia is a psychotic disorder characterized by delusions, hallucinations, negative symptoms, as well as behavioral and cognitive dysfunction. It is a pathoetiologically heterogeneous disorder involving complex interrelated mechanisms that include oxidative stress and neuroinflammation. Neurovascular endothelial dysfunction and blood-brain barrier (BBB) hyperpermeability are established mechanisms in neurological disorders with comorbid psychiatric symptoms such as epilepsy, traumatic brain injury, and Alzheimer's disease. Schizophrenia is frequently comorbid with medical conditions associated with peripheral vascular endothelial dysfunction, such as metabolic syndrome, cardiovascular disease, and diabetes mellitus. However, the existence and etiological relevance of neurovascular endothelial dysfunction and BBB hyperpermeability in schizophrenia are still not well recognized. Here, we review the growing clinical and experimental evidence, indicating that neurovascular endotheliopathy and BBB hyperpermeability occur in schizophrenia patients. We present a theoretical integration of human and animal data linking oxidative stress and neuroinflammation to neurovascular endotheliopathy and BBB breakdown in schizophrenia. These abnormalities may contribute to the cognitive and behavioral symptoms of schizophrenia via several mechanisms involving reduced cerebral perfusion and impaired homeostatic processes of cerebral microenvironment. Furthermore, BBB disruption can facilitate interactions between brain innate and peripheral adaptive immunity, thereby perpetuating harmful neuroimmune signals and toxic neuroinflammatory responses, which can also contribute to the symptoms of schizophrenia. Taken together, these findings support the "mild encephalitis" hypothesis of schizophrenia. If neurovascular abnormalities prove to be etiologically relevant to the neurobiology of schizophrenia, then targeting these abnormalities may represent a promising therapeutic strategy.

Severity of hypertension predicts the generalized neurocognitive deficit in schizophrenia

Individuals with schizophrenia have been found to display neurocognitive deficits on the order of 1 standard deviation below the mean of healthy controls on a range of cognitive domains, with no clear pattern of deficits that characterizes the majority of individuals with schizophrenia. Such findings have led some to suggest that schizophrenia is characterized by a "generalized" neurocognitive deficit, implying that a common underlying etiology impacts all cognitive domains. Central nervous system accounts of the generalized deficit have been proposed (e.g., NMDA and GABA interneuron receptor dysfunction); however, there may also be more diffuse "general systems" abnormalities that affect brain function. The current study evaluated the role of one type of general systems abnormality, metabolic dysfunction, on global cognitive functioning in a sample of outpatients with schizophrenia (n=27) and demographically matched healthy controls (n=33). Participants completed a battery of neuropsychological tests, as well as metabolic measurements to assess blood glucose, blood pressure, and abdominal obesity. Results indicated that higher pulse pressure predicted the generalized neurocognitive deficit in schizophrenia, but not healthy controls; however, blood glucose and abdominal obesity did not predict cognitive performance in either group. These findings provide support for the role of metabolic abnormalities in the generalized neurocognitive deficit in schizophrenia, and suggest that treatment of hypertension may be a novel adjunctive treatment target for remediating cognitive deficits in schizophrenia.

Potentially inappropriate psychotropic prescription at discharge is associated with lower functioning in the elderly psychiatric inpatients. A cross-sectional study

OBJECTIVE

The objectives are to determine the rate of potentially inappropriate psychotropic (PIP) prescription at discharge in the elderly psychiatric inpatients and to determine whether PIP is associated with lowered functioning outcomes.

METHODS

Sociodemographic, clinical, and treatment data for all inpatients aged ≥ 65 years consecutively hospitalized during 1 year in 13 psychiatry departments was analyzed. PIP+/PIP- groups were defined according to the French-updated Beers criteria. Daily functioning was evaluated by the daily living (ADL) scale. Logistic regression analysis was used to estimate odds ratios for the association between PIP administration at discharge and respectively functioning and potential confounding factors.

RESULTS

Data was obtained for 327 patients. Overall, 124 (37.9 %) patients were males, and the mean age was 73.9 years (SD = 5.6); 163 (49.8 %) patients were diagnosed with affective disorders and 89 (27.2 %) with schizophrenia/schizotypal/delusional disorders. Overall, 249 (76.1 %) had one or more PIP medications, mainly anxiolytics (69.9 %) and hypnotics (17.2 %). In a multivariate analysis, PIP prescription at discharge has been associated with patient lowered personal care functioning, independently of age, gender, and psychiatric or somatic diagnoses (OR = 0.88 (0.79-0.97, p = 0.01).

CONCLUSION

In the current increasingly fragmented health care systems, special attention must be given to PIP prescription in older population suffering from psychiatric disorders. Using the Beers criteria, the present study demonstrates the high prevalence of PIP prescription, which concerns a large panel of drugs but mostly anxiolytics and hypnotics independently of psychiatric or somatic diagnoses and sociodemographic characteristics. Our study has demonstrated for the first time an association between PIP prescription and lowered patient functioning. Further longitudinal studies should confirm a potential causal relation.

Glutathione S-transferase K1 genotype and overweight status in schizophrenia patients: A pilot study

Elevated oxidative stress in mitochondria and mitochondrial dysfunction are associated with weight gain in schizophrenia (SCZ) patients. Glutathione S-transferase kappa 1 (GSTK1) protects cells against exogenous and endogenous oxidative stress in the mitochondria. This exploratory study investigated the possible effects of a common GSTK1 polymorphism (rs1917760, G-1308T) on the risk for overweight status among 329 SCZ patients and 305 age- and gender-matched controls and on the GSTK1 mRNA level in peripheral blood mononuclear cells among 14 SCZ patients. The GSTK1 T/T genotype was associated with having a higher BMI value among SCZ male patients, whereas this genotype tended to be associated with a lower BMI value among female patients. Conversely, these associations were not observed among the controls. The GSTK1 T/T genotype was associated with decreased GSTK1 mRNA level among SCZ patients. The GSTK1 T/T genotype may be a novel risk factor for the prediction of overweight status in SCZ male patients, although the results of this pilot study should be verified by a larger study.

Metabolic syndrome in schizophrenia patients associated with poor premorbid school performance in early adolescence

OBJECTIVE

More than 40% of patients with schizophrenia have an additional diagnosis of the metabolic syndrome (MS), possibly related to poor cognition. This study investigated premorbid and current cognitive functioning in schizophrenia and co-occurrence of MS.

METHOD

A total of 104 participants with schizophrenia with MS and 142 without MS were included. Neuropsychological assessment was carried out using the Wechsler Adult Intelligence Scale-III, Word Learning Task, and Continuous Performance Test-HQ. Premorbid functioning was assessed retrospectively with the Premorbid Adjustment Scale. anovas were used to examine differences between participants with and without MS.

RESULTS

Subjects with and without MS did not differ concerning current, lifetime and amount substance use, duration/severity of illness, parental socioeconomic status (SES), and type/amount of antipsychotic medication. We found that poor school performance between the ages 12 and 16 is associated with MS in schizophrenia. Educational level and current cognitive functioning in participants with MS deviate as compared to those without MS.

CONCLUSION

Subjects with MS had impaired premorbid cognition in adolescence and lower educational achievement, irrespective of parental SES. This suggests poor premorbid cognitive functioning is a risk factor for metabolic complications later in life. Future studies are needed to examine whether cognitive interventions have beneficial effects on general health in schizophrenia.

Functional brain substrate of quality of life in patients with schizophrenia: A brain SPECT multidimensional analysis

The aim of this study was to investigate the functional brain substrate of quality of life (QoL) in patients with schizophrenia. Participants comprised 130 right-handed patients with schizophrenia who underwent whole-brain single photon emission computed tomography (SPECT) with (99m)Tc-labeled ethylcysteinate dimer ((99m)Tc-ECD) for exploring correlations of regional cerebral blood flow (rCBF) with the eight dimensions score of the Schizophrenia Quality of Life questionnaire (S-QoL 18). A significant positive correlation was found between the global index of the S-QoL 18 and rCBF in the right superior temporal sulcus and between psychological well-being dimension and rCBF in Brodmann area (BA)6, BA8, BA9, and BA10 and between self-esteem dimension and rCBF in striatum and between family relationship dimension and rCBF in BA1, BA2, BA3, BA4, BA8, BA22, BA40, BA42 and BA44 and between relationship with friends dimension and rCBF in BA44 and between physical well-being dimension and rCBF in parahippocampal gyrus, and finally between autonomy dimension and rCBF in cuneus and precuneus. A significant negative correlation was found between resilience dimension and rCBF in precuneus and between sentimental life dimension and rCBF in BA10. Our findings provide neural correlates of QoL. Brain regions involved in cognitions, emotional information processing and social cognition underlie the different QoL dimensions.

A structural equation modelling approach to explore the determinants of quality of life in schizophrenia

OBJECTIVE

This study aimed to analyse the relationships among psychotic symptoms, depression, neurocognition and functioning as determinants of quality of life (QoL) in patients with schizophrenia.

METHODS

In this cross-sectional study, we evaluated QoL with the Schizophrenia Quality of Life 18-item scale (S-QoL 18), neurocognition with multiple tests exploring memory, attention and executive functions, the severity of psychotic symptoms with the Positive and Negative Syndrome Scale (PANSS), depression with the Calgary Depression Scale for Schizophrenia (CDSS) and functioning using the Functional Remission Of General Schizophrenia (FROGS) scale. We used Structural Equation Modelling (SEM) to describe the relationships among the severity of psychotic symptoms, depression, neurocognition, functioning and QoL.

RESULTS

Two hundred and seventy-one outpatients with schizophrenia participated in our study. SEM showed good fit with χ(2)/df=1.97, root mean square error of approximation=0.06, comparative fit index=0.93 and standardized root mean square residuals=0.05. This model revealed that depression was the most important feature associated with QoL, mainly for the self-esteem, autonomy and resilience dimensions (direct path coefficient=-0.46). The direct path between functioning and QoL was also significant (path coefficient=0.26). The severity of psychotic symptoms and neurocognitive impairment were weakly and indirectly associated with QoL via functioning (path coefficients=-0.18 and 0.04, respectively).

CONCLUSIONS

This study contributes to a better understanding of the determinants of QoL in schizophrenia. Our findings should be considered in developing effective strategies for improving QoL among this population.

Association of metabolic syndrome with sensory gating deficits in patients with chronic schizophrenia

Metabolic syndrome is more prevalent in schizophrenia than in the general population and is associated with an increased rate of morbidity. It has been associated with cognitive impairments in schizophrenia, which are a core deficit in patients with chronic schizophrenia. Sensory gating deficit is also a core deficit in schizophrenia. The principal objective of this study was to investigate the relationship between sensory gating deficit and metabolic syndrome in patients with schizophrenia, after adjusting for key confounding factors. We hypothesized that patients with metabolic syndrome exhibit a higher rate of sensory gating deficit compared to those without metabolic syndrome. This study investigated sensory gating with the auditory event-related potential method by measuring P50 amplitude changes in a double click conditioning-testing procedure in 51 patients with schizophrenia. Patients with metabolic syndrome (n = 14) had a higher rate of sensory gating deficit (P50 suppression <50%) (p < 0.001) compared to those without metabolic syndrome (n = 37). This result remained significant (B = 2.94, Wald = 8.32, p = 0.004) after taking into account 5 potential confounding factors (age, gender, duration of disorder, Fagerström test, presence of clozapine or olanzapine). In patients without metabolic syndrome, sensory gating deficit was linked to a poorer attentional performance (rho = -0.371, p = 0.05). In patients with metabolic syndrome, sensory gating deficit was linked to poorer memory performance (rho = -0.635, p = 0.02). These findings suggest that metabolic syndrome may be linked to sensory gating deficit in patients with schizophrenia and that the relationship between neurocognitive function and sensory gating deficit could be affected by the metabolic status of the patients. Further studies are needed to address the causal relationship between sensory gating deficit related to schizophrenia, cognitive impairments and metabolic syndrome.

Quality of life is associated with chronic inflammation in schizophrenia: a cross-sectional study

Inflammation may play a crucial role in the pathogenesis of schizophrenia. However, the association between chronic inflammation and health outcomes in schizophrenia remains unclear, particularly for patient-reported outcomes. The aim of this study was to investigate the relationship between quality of life (QoL) and chronic inflammation assessed using C -Reactive Protein (CRP) in patients with schizophrenia. Two hundred and fifty six patients with schizophrenia were enrolled in this study. After adjusting for key socio-demographic and clinical confounding factors, patients with high levels of CRP (>3.0 mg/l) had a lower QoL than patients with normal CRP levels (OR = 0.97, 95% CI = 0.94–0.99). An investigation of the dimensions of QoL revealed that psychological well-being, physical well-being and sentimental life were the most salient features of QoL associated with CRP. Significant associations were found between lower educational level (OR = 4.15, 95% CI = 1.55–11.07), higher body mass index (OR = 1.16, 95% CI = 1.06–1.28), higher Fagerström score (OR = 1.22, 95% CI = 1.01–1.47) and high levels of CRP. After replications with longitudinal approaches, the association between QoL and chronic inflammation may offer interesting interventional prospects to act both on inflammation and QoL in patients with schizophrenia.