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

Quality of Life and C-Reactive Protein in Patients with Schizophrenia: A Cross-Sectional Study

Objective

The connection between chronic inflammation and the quality of life (QOL) in individuals diagnosed with schizophrenia lacks clarity. This study aimed to achieve 2 primary objectives: (1) assess the QOL among outpatients with schizophrenia and (2) explore the potential correlation between reduced QOL and heightened levels of C-reactive protein (CRP) in patients with schizophrenia.

Methods

The research included 129 outpatients diagnosed with schizophrenia who were receiving care at the psychiatry department of the University Hospital Mohamed VI in Marrakech, Morocco. Disease severity was evaluated using the Positive and Negative Syndrome Scale (PANSS), while the QOL was measured using the Moroccan Arabic version of The Schizophrenia Quality of Life questionnaire. Patients were categorized into 2 groups based on their CRP levels: normal CRP (≤5.0 mg/L) and high CRP (>5.0 mg/L). A comparative analysis of sociodemographic, clinical, biological, and quality of life factors was conducted between the 2 groups (normal CRP and high CRP).

Results

The group with elevated CRP levels exhibited higher scores in various PANSS categories, including PANSS total score (P ≤ .01), PANSS positive score (P ≤ .01), PANSS negative score (P ≤ .01), and PANSS general score (P ≤ .01). After adjusting for sociodemographic and clinical variables, individuals with elevated CRP levels demonstrated lower QOL compared to those with normal CRP levels (OR = 0.57, 95% CI = 0.46-0.68). Significant associations were noted between male gender (OR = 0.047, 95% CI = 0.01-0.26), earlier onset of the condition (OR = 0.54, 95% CI = 0.33-0.82), current tobacco smoking (OR = 0.015, 95% CI = 0.00-0.08), and heightened CRP levels.

Conclusion

Our study suggests that higher CRP is associated with lower QOL levels in schizophrenia.

Alterations in inflammatory markers after a 12-week exercise program in individuals with schizophrenia-a randomized controlled trial

Background

In individuals with schizophrenia, inflammation is associated with depression, somatic comorbidity and reduced quality of life. Physical exercise is known to reduce inflammation in other populations, but we have only limited knowledge in the field of schizophrenia. We assessed inflammatory markers in plasma samples from individuals with schizophrenia participating in an exercise intervention randomized controlled trial. We hypothesized that (i) physical exercise would reduce levels of inflammatory markers and (ii) elevated inflammatory status at baseline would be associated with improvement in cardiorespiratory fitness (CRF) following intervention.

Method

Eighty-two individuals with schizophrenia were randomized to a 12-week intervention of either high-intensity interval training (HIIT, n = 43) or active video gaming (AVG, n = 39). Participants were assessed at baseline, post intervention and four months later. The associations between exercise and the inflammatory markers soluble urokinase plasminogen activator receptor, c-reactive protein, tumor necrosis factor (TNF), soluble TNF receptor 1 and interleukin 6 (IL-6) were estimated using linear mixed effect models for repeated measures. For estimating associations between baseline inflammation and change in CRF, we used linear regression models.

Results

Our main findings were (i) TNF and IL-6 increased during the intervention period for both groups. Other inflammatory markers did not change during the exercise intervention period; (ii) baseline inflammatory status did not influence change in CRF during intervention, except for a positive association between baseline IL-6 levels and improvements of CRF to post intervention for both groups.

Conclusion

In our study, HIIT and AVG for 12-weeks had no reducing effect on inflammatory markers. Patients with high baseline IL-6 levels had a positive change in CRF during intervention. In order to increase our knowledge regarding association between inflammatory markers and exercise in individuals with schizophrenia, larger studies with more frequent and longer exercise bout duration are warranted.

Suppressing leukocyte Kv1.3-channels by commonly used drugs: A novel therapeutic target for schizophrenia?

Recent studies revealed the involvement of "chronic inflammation" in the pathogenesis of schizophrenia. In schizophrenia and some neurodegenerative disorders that are caused by inflammation, T-lymphocytes and macrophages were hyperactivated or proliferated in the central nervous system, being accompanied by the overexpression of delayed rectifier K⁺-channels (Kv1.3) within the cells. In our previous basic studies, in addition to nonsteroidal anti-inflammatory drugs (NSAIDs) and statins, antibiotics (clarithromycin, chloroquine), anti-hypertensive drugs (nifedipine, benidipine, diltiazem, verapamil) and anti-allergic drugs (cetirizine, fexofenadine, azelastine, terfenadine) strongly suppressed the Kv1.3-channel activity and pro-inflammatory cytokine production from lymphocytes. Given such pharmacological properties of these commonly used drugs, they may be useful in the treatment of schizophrenia, in which the enhanced cellular immunity and the subsequent release of excessive cytokines are responsible for the pathogenesis.

A comprehensive model of predictors of quality of life in older adults with schizophrenia: results from the CSA study

BACKGROUND

Numerous factors are known to influence quality of life of adults with schizophrenia. However, little is known regarding the potential predictors of quality of life in the increasing population of older adults with schizophrenia. The main objective of the present study was to propose a comprehensive model of quality of life in this specific population.

METHODS

Data were derived from the Cohort of individuals with Schizophrenia Aged 55 years or more (CSA) study, a large (N = 353) multicenter sample of older adults with schizophrenia or schizoaffective disorder recruited from French community mental-health teams. We used structural equation modeling to simultaneously examine the effects of six broad groups of clinical factors previously identified as potential predictors of quality of life in this population, including (1) severity of general psychopathology, (2) severity of depression, (3) severity of cognitive impairment, (4) psychotropic medications, (5) general medical conditions and (6) sociodemographic characteristics.

RESULTS

General psychopathology symptoms, and in particular negative and depressive symptoms, cognitive impairment, reduced overall functioning and low education were significantly and independently associated with diminished quality of life (all p < 0.05). Greater number of medical conditions and greater number of antipsychotics were also independently and negatively associated with quality of life, although these associations did not reach statistical significance in sensitivity analyses, possibly due to limited statistical power.

CONCLUSION

Several domains are implicated in quality of life among older adults with schizophrenia. Interventions targeting these factors may help improve importantly quality of life of this vulnerable population.

Plasma 25-hydroxyvitamin D levels, quality of life, inflammation and depression in older adults: Are they related?

BACKGROUND AND OBJECTIVES

This study aimed to determine whether there is an association between inflammation and depression taking into account the effect of several confounders, but specially plasma 25-hydroxyvitamin D (25[OH]D) levels.

MATERIAL AND METHODS

A cross-sectional study was conducted on adults (n = 346) aged 60 years or older recruited from primary healthcare centres. Depression was assessed by the Geriatric Depression Scale (GDS), while plasma 25(OH)D and inflammatory cytokines were measured following routine biochemical laboratory protocols.

RESULTS

Subjects were divided into two subgroups according to their depression status, and matched in their baseline conditions using random forest-based propensity scores. Both groups were rather similar in regard to most variables, apart from quality of life (p < 0.001) and plasma levels of IL-6 (p = 0.03). The overall prevalence of vitamin D deficiency was 36.3% (95% Confidence Interval [95% CI], 30.2%-42.5%), without a significant difference between depression groups (p = 0.2). A significant association was observed between GDS score and plasma IL-6 levels only among those with SF-6D score between 0.26 and 0.50 (p = 0.001).

CONCLUSIONS

The association between inflammation and depression is more likely to be due to a moderation influence of quality of life rather than plasma 25(OH)D levels. However, further studies are needed to ascertain the effect of a poor quality of life leading to chronic inflammation and poor health upon longer periods of follow-up.

Psychiatric symptoms and quality of life in older adults with schizophrenia spectrum disorder: results from a multicenter study

The severity of psychopathology has a strong negative impact on quality of life (QoL) among older adults with schizophrenia spectrum disorder. However, because these subjects generally experience multiple psychiatric symptoms, it remains unclear whether decreased QoL in this population is due to specific symptoms (e.g., hallucinations), specific dimensions of psychopathology (e.g., negative symptoms), a general psychopathology dimension representing the shared effect across all psychiatric symptoms, or a combination of these explanations. Data were derived from the Cohort of individuals with Schizophrenia Aged 55 years or more (CSA) study, a large (N = 353) multicenter sample of older adults with schizophrenia spectrum disorder recruited from French public-sector psychiatric departments. We used structural equation modeling to examine the shared and specific effects of psychiatric symptoms on QoL, while adjusting for sociodemographic characteristics, general medical conditions, global cognitive functioning and psychotropic medications. Psychiatric symptoms and QoL were assessed face-to-face by psychiatrists using the Brief Psychiatric Rating Scale (BPRS) and the Quality of Life Scale (QLS). Among older adults with schizophrenia spectrum disorder, effects of psychiatric symptoms on QoL were exerted mostly through a general psychopathology dimension (β = - 0.43, p < 0.01). Negative symptom dimension had an additional negative effect on QoL beyond the effect of that factor (β = - 0.28, p < 0.01). Because psychiatric symptoms affect QoL mainly through two dimensions of psychopathology, i.e., a general psychopathology dimension and a negative symptom dimension, mechanisms underlying those dimensions should be considered as promising targets for therapeutic interventions to substantially improve quality of life of this vulnerable population.

Cytokine Alterations in Schizophrenia: An Updated Review

Schizophrenia, a multisystem disorder with an unknown etiology, is associated with several immune dysfunctions, including abnormal levels of circulating cytokines. In this review, we investigated the changes of cytokines in schizophrenic patients, their connection with behavioral symptoms severity and their potential clinical implications. We also assessed the possible causative role of abnormal cytokine levels in schizophrenia pathogenesis. Based on meta-analyses, we categorized cytokines according to their changes in schizophrenic patients into four groups: (1) increased cytokines, including interleukin (IL)-6, tumor necrosis factor (TNF)-α, IL-1β, IL-12, and transforming growth factor (TGF)-β, (2) non-altered cytokines, including IL-2, IL-4, and IL-17, (3) increased or non-altered cytokines, including IL-8 and interferon (IFN)-γ, and (4) IL-10 with increased, decreased, and non-altered levels. Notably, alterations in cytokines may be variable in four different categories of SP, including first-episode and drug-naïve, first-episode and non-drug-naïve, stable chronic, and chronic in acute relapse. Furthermore, disease duration, symptoms severity, incidence of aggression, and cognitive abilities are correlated with levels of certain cytokines. Clinical implications of investigating the levels of cytokine in schizophrenic patients include early diagnosis, novel therapeutic targets development, patient stratification for choosing the best therapeutic protocol, and predicting the prognosis and treatment response. The levels of IL-6, IL-8, IFN-γ, IL-2 are related to the treatment response. The available evidence shows a potential causative role for cytokines in schizophrenia development. There is a substantial need for studies investigating the levels of cytokines before disease development and delineating the therapeutic implications of the disrupted cytokine levels in schizophrenia.

Relationships of blood proinflammatory markers with psychological resilience and quality of life in civilian women with posttraumatic stress disorder

Individuals with posttraumatic stress disorder (PTSD) show low resilience and impaired quality of life (QOL). Accumulating evidence shows that PTSD is associated with increased inflammation. Studies suggest that inflammation can be a key mechanism underlying low resilience/QOL, but this relationship has been understudied in individuals with PTSD. Here, we investigated the association of blood proinflammatory markers with self-reported resilience and QOL in civilian women with PTSD. Fifty-six women with PTSD and 73 healthy control women participated in this study. Resilience was assessed using the Connor-Davidson Resilience Scale. QOL was assessed using the World Health Organization Quality of Life-BREF. Blood samples were collected for the measurement of three proinflammatory markers including interleukin-6 (IL-6), high-sensitivity tumor necrosis factor-α, and high-sensitivity C-reactive protein (hsCRP). Compared to controls, patients showed significantly higher IL-6 levels and lower resilience and QOL. In patients, IL-6 levels were significantly negatively correlated with resilience, and hsCRP levels were significantly negatively correlated with psychological QOL. These results show that increased levels of proinflammatory markers including IL-6 and hsCRP are associated with lower psychological resilience and QOL in PTSD patients. Our findings suggest that interventions and treatments targeting inflammation may aid in the recovery from PTSD and lead to better prognosis.

Sex Difference in the Association between High-sensitivity C-reactive Protein and Depression: The 2016 Korea National Health and Nutrition Examination Survey

Elevated levels of circulating high-sensitivity C-reactive protein (hs-CRP) have been observed in depression, with the body mass index (BMI) being a major mediator of this association. However, the sex difference in the association between hs-CRP and depression remains unclear. This study aimed to investigate the sex difference in the association between hs-CRP and depression. Data from the 2016 Korea National Health and Nutritional Examination Survey were used for our study. High hs-CRP was defined as >3.0 mg/L, while depression was determined using a cut-off score of 10 in the Patient Health Questionnaire-9. The study population comprised 5,483 Korean adults. Men with high hs-CRP levels showed statistically higher prevalence of depression than those with low hs-CRP levels (8.90% vs. 3.65%, P < 0.0001). The high hs-CRP group was 1.86 times more likely to have depression after adjusting for BMI and other covariates in men (adjusted odds ratio: 1.86; 95% confidence interval: 1.07–3.25; P = 0.029). Meanwhile, no statistically significant association between hs-CRP and depression was found among women. Depression was considerably associated with hs-CRP only in men, indicating a biological difference between men and women that can independently modify the relationship between hs-CRP and depression.

Inflammation and quality of life in later life: findings from the health, well-being and aging study (SABE)

BACKGROUND

Few studies have specifically investigated the inverse relationship between reduced quality of life in different domains and elevated C-reactive protein (CRP) serum levels in older adults. Therefore, this study investigates the cross-sectional association between quality of life and inflammation in older Brazilian adults.

METHODS

Data were collected from 1255 participants from the third wave (2010) of the Brazilian Health, Well-being and Aging study (SABE), a community-based cohort study of aging. Inflammation was assessed using CRP serum levels and quality of life (QoL) was measured using the 12-item Short-Form Health Survey (SF-12) questionnaire. The covariates included age, sex, education level, financial sufficiency, number of non-communicable diseases, self-reported doctor diagnosed diseases, Activity of Daily Living (ADL) difficulties, Body Mass Index (BMI), and waist circumference.

RESULTS

The fully adjusted models showed that older adults with low scores in the physical domain of the SF12 (OR 1.34, 95%CI 1.02;1.77) and high BMI values (> 30) (OR 2.05, 95%CI 1.50;2.81) were more likely to present high CRP serum levels.

CONCLUSION

Our findings suggest a significant association of lower scores in the physical domain of quality of life and the presence of obesity with high CRP serum levels.

C-reactive protein is associated with severity of thought and language dysfunction in patients with schizophrenia

BACKGROUND

Numerous studies have demonstrated an association between C-reactive protein (CRP) levels and schizophrenia. However, the findings on psychotic severity and cognition remain inconsistent. The relationship between CRP and formal thought disorder in subdomains remains unclear.

METHODS

We enrolled stable patients (defined as those who had no treatment changes during the 4-week period before evaluation) with a diagnosis of schizophrenia or schizoaffective disorder, according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. We used the 30-item Thought and Language Disorder (TALD) scale to evaluate thought and language dysfunction over four subscales. We assessed psychotic symptoms using the Positive and Negative Syndrome Scale (PANSS). We collected fasting venous blood and measured plasma CRP levels.

RESULTS

We enrolled 60 patients with schizophrenia. All patients received TALD and PANSS evaluation, and 33 of them had their CRP levels checked. The multivariate regression analysis indicated that CRP levels were significantly associated with the total score on the TALD (t=2.757, P=0.010) and the TALD Objective Positive subscale (t=2.749, P=0.011), after sex, age, duration of illness (in years), and use of atypical antipsychotics were adjusted for. Additionally, CRP was significantly associated with the PANSS positive subscale (t=2.102, P=0.045). A significantly positive correlation was observed between the total scores on the TALD scale and PANSS (ρ =0.751, P<0.001).

CONCLUSION

Our results suggest that abnormal CRP levels are significantly associated with formal thought and language dysfunction in the Objective Positive subdomain and positive psychotic symptoms.

Exploring the associations between systemic inflammation, obesity and healthy days: a health related quality of life (HRQOL) analysis of NHANES 2005-2008

Background

Obesity is positively associated with low-level chronic inflammation, and negatively associated with several indices of health-related quality of life (HRQOL). It is however not clear if obesity-associated inflammation is partly responsible for the observed negative associations between obesity and HRQOL, and also whether systemic inflammation independently affects HRQOL. We conducted an exploratory analysis to investigate the relationships between obesity, systemic inflammation and indices of HRQOL, using NHANES survey data.

Methods

Data for the variables of interest were available for 6325 adults (aged 20–75 years, BMI > 18.5 kg/m²). Demographic, body mass index (BMI), C-reactive protein (CRP), inflammatory disease status, medication use, smoking, and HRQOL data were obtained from NHANES (2005–2008) and analyzed using sampling-weighted generalized linear models. Data was subjected to multiple imputation in order to mitigate information loss from survey non-response. Both main effects and interaction effects were analyzed to evaluate possible mediation or moderation effects. Model robustness was ascertained via sensitivity analysis. Averaged results from the imputed datasets were reported in as odds ratios (OR) and confidence intervals (CI).

Results

Obesity was positively associated with poor physical healthy days (OR: 1.59, 95% CI: 1.15–2.21) in unadjusted models. ‘Elevated’ and ‘clinically raised’ levels of the inflammation marker CRP were also positively associated with poor physical healthy days (OR = 1.61, 95% CI: 1.23–2.12, and OR = 2.45, 95% CI: 1.84–3.26, respectively); additionally, ‘clinically raised’ CRP was positively associated with mental unhealthy days (OR = 1.66, 95% CI: 1.26–2.19). The association between obesity and physical HRQOL was rendered non-significant in models including CRP. Association between ‘elevated’ and ‘clinically raised’ CRP and physical unhealthy days remained significant even after adjustment for obesity or inflammation-modulating covariates (OR = 1.36, 95% CI: 1.02–1.82, and OR = 1.75, 95% CI: 1.21–2.54, respectively).

Conclusions

Systemic inflammation appears to mediate the association between obesity and physical unhealthy days. Clinically raised inflammation is an independent determinant of physical and mental unhealthy days. Importantly, elevated (but sub-clinical) inflammation is also negatively associated with physical healthy days, and may warrant more attention from a population health perspective than currently appreciated.

Electronic supplementary material

The online version of this article (10.1186/s40608-018-0196-2) contains supplementary material, which is available to authorized users.

Health-related quality of life in adolescents and the retinal microvascular structure

We aimed to investigate whether health-related quality of life (HRQoL) is associated with retinal vascular caliber, an indicator of subclinical cardiovascular disease risk. 1600 students aged between 11–19 years (821 girls and 779 boys) were examined during 2009–2011. Retinal vessel caliber was measured from digital retinal images. HRQoL was assessed by the Pediatric Quality of Life Inventory (PedsQL). In the overall cohort, each 1-unit increase in PedsQL total score and the psychosocial summary score was associated with ~0.05 μm narrowing in retinal arteriolar caliber (multivariable-adjusted p-value = 0.01). Participants in the lowest versus highest tertile of PedsQL total score, psychosocial summary, social and school item scores had significantly wider retinal arteriolar caliber: 161.7 μm versus 160.2 μm (p = 0.02); 161.6 μm versus 160.0 μm (p = 0.02); 161.6 μm versus 159.9 μm (p = 0.002); and 161.6 μm versus 159.9 μm (p = 0.01), respectively. Significant interactions (p < 0.05) were observed between gender and PedsQL total score with retinal arteriolar calibre. In boys, inverse associations were observed between PedsQL total score (p = 0.01), psychosocial summary (p = 0.01), and social scores (p = 0.01) and retinal arteriolar caliber. No significant associations were observed between PedsQL scores and retinal vessel caliber in girls. Diminished HRQoL in adolescents was independently associated with structural retinal microvascular changes.

C-Reactive Protein as a Peripheral Biomarker in Schizophrenia. An Updated Systematic Review

Objectives: The objective of this systematic review was to synthetize the published data on the relationships between elevated blood C-reactive protein (CRP) levels and schizophrenia (SZ) onset risk, illness characteristics and treatments, cognition and physical health. Method: The systematic bibliographic searches have been carried out according to the Cochrane methodology. Medline, web of science, Google Scholar with each database being searched from inception to November 2017. Results: 53 studies were included in the present review. While meta-analyses including case-control studies suggest a clear association between CRP and SZ, one other study has suggested that CRP-associated genes were associated with a lower risk of SZ onset. Increased CRP has been significantly associated with positive symptoms in acute phase psychosis, while studies including community-dwelling stabilized subjects did not find such an association. Abnormal CRP has been associated with a wide range of cognitive impairment in SZ stabilized individuals. Body Mass index has been extensively associated with increased CRP in SZ subjects; and increased CRP has been identified as a risk factor for metabolic syndrome and cardiovascular risk in SZ subjects. Increased CRP has also been associated with high nicotine dependence in SZ smokers and one study has suggested that increased CRP was associated with sedentary behavior. Conclusion: In the light of the above-mentioned studies, increased hs-CRP may be reasonably suggested as a marker for SZ onset risk, as well as a risk factor for increased positive symptoms, cognitive impairment, hypovitaminosis D, microbiota disturbances, cardiovascular and metabolic syndrome risk in SZ subjects, and increased nicotine dependence in SZ smokers. In case of increased CRP levels, anti-inflammatory strategies (add-on anti-inflammatory drugs including aspirin and omega 3 fatty acids, vitamin D supplementation, physical activity, probiotics) should be also further evaluated. Limits: Most of the studies were cross-sectional and cohort studies are needed to determine the temporal relationship between increased CRP and the psychiatric outcomes.

Protein-C Reactive as Biomarker Predictor of Schizophrenia Phases of Illness? A Systematic Review

BACKGROUND

Schizophrenia is a complex illness in which genetic, environmental, and epigenetic components have been implicated. However, recently, psychiatric disorders appear to be related to a chronic inflammatory state, at the level of specific cerebral areas which have been found as well impaired and responsible for schizophrenia symptomatology. Hence, a role of inflammatory mediators and cytokines has been as well defined. Accordingly, the role of an acute inflammatory phase protein, the C-reactive protein (CRP) has been recently investigated.

OBJECTIVE

The objective of the present study is to evaluate how PCR may represent a biomarker in schizophrenia, i.e. correlated with illness phases and/or clinical manifestation and/or psychopathological severity.

METHODS

A systematic review was here carried out by searching the following keywords ((C-reactive protein AND ((schizophrenia) OR (psychotic disorder))) for the topics 'PCR' and 'Schizophrenia', by using MESH terms.

RESULTS

An immune dysfunction and inflammation have been described amongst schizophrenic patients. Findings reported elevated CRP levels in schizophrenia, mainly correlated with the severity of illness and during the recrudescent phase. CRP levels are higher when catatonic features, negative symptomatology and aggressiveness are associated. CRP levels appeared not to be related to suicidal behaviour and ideation.

CONCLUSION

CRP and its blood levels have been reported higher amongst schizophrenic patients, by suggesting a role of inflammation in the pathogenesis of schizophrenia. Further studies are needed to better understand if CRP may be considered a biomarker in schizophrenia.

Estrogens and the cognitive symptoms of schizophrenia: Possible neuroprotective mechanisms

Schizophrenia is a complex neuropsychiatric illness with marked sex differences. Women have later onset and lesser symptoms, which has led to the hypothesis that estrogens are protective in schizophrenia. Cognitive dysfunction is a hallmark of the disease and the symptom most correlated with functional outcome. Here we describe a number of mechanisms by which estrogens may be therapeutic in schizophrenia, with a focus on cognitive symptoms. We review the relationship between estrogens and brain derived neurotrophic factor, neuroinflammation, NMDA receptors, GABA receptors, and luteinizing hormone. Exploring these pathways may enable novel treatments for schizophrenia and a greater understanding of this devastating disease.

Nicotine dependence is associated with depression and childhood trauma in smokers with schizophrenia: results from the FACE-SZ dataset

In a perspective of personalized care for smoking cessation, a better clinical characterization of smokers with schizophrenia (SZ) is needed. The objective of this study was to determine the clinical characteristics of SZ smokers with severe nicotine (NIC) dependence. 240 stabilized community-dwelling SZ smokers (mean age = 31.9 years, 80.4% male gender) were consecutively included in the network of the FondaMental Expert Centers for Schizophrenia and assessed with validated scales. Severe NIC dependence was defined by a Fagerstrom questionnaire score ≥ 7. Depression was defined by a Calgary score ≥ 6. Childhood trauma was self-reported by the Childhood Trauma Questionnaire score (CTQ). Ongoing psychotropic treatment was recorded. Severe NIC dependence was identified in 83 subjects (34.6%), depression in 60 (26.3%). 44 (22.3%) subjects were treated by antidepressants. In a multivariate model, severe NIC dependence remained associated with depression (OR = 3.2, p = 0.006), male gender (OR = 4.5, p = 0.009) and more slightly with childhood trauma (OR = 1.03, p = 0.044), independently of socio-demographic characteristics, psychotic symptoms severity, psychotropic treatments and alcohol disorder. NIC dependence was independently and strongly associated with, respectively, depression and male gender in schizophrenia, and only slightly with history of childhood trauma. Based on these results, the care of both nicotine dependence and depression should be evaluated for an effective smoking cessation intervention in schizophrenia.

Chronic low-grade peripheral inflammation is associated with severe nicotine dependence in schizophrenia: results from the national multicentric FACE-SZ cohort

Chronic peripheral inflammation (CPI) has been associated with cognitive impairment in schizophrenia (SZ). However, its sources remain unclear, more specifically it is not known whether tobacco smoking is a source of inflammation or not in SZ subjects. Moreover, nicotine (NIC), the major psychoactive compound of tobacco, shows strong anti-inflammatory properties in vitro, as well as inducing a severe biological dependence when administered repeatedly. The objective of the present study was to determine if CPI was associated with tobacco smoking and/or NIC dependence in schizophrenia. Three hundred and forty five stabilized community-dwelling SZ subjects aged 16 years or older (mean age = 32 years, 73% male) were consecutively included in the network of the FondaMental Expert Centers for Schizophrenia and assessed with validated scales. CPI was defined by a highly sensitive C-reactive protein (hsCRP) ≥3 mg/L. Current tobacco status was self-declared. Severe NIC dependence was defined by a Fagerstrom Test for Nicotine Dependence score ≥7. Overall, 159 (46.1%) were non-smokers, 117 (33.9%) and 69 (20%) were current tobacco smokers with, respectively, low and severe nicotine dependence. In a multivariate model, CPI remained associated with severe NIC dependence (29 vs 15%, OR = 2.8, p = 0.003) and body mass index (OR = 1.1, p < 0.0001), independently of socio-demographic characteristics and antidepressant intake. No association of CPI with low to moderate tobacco smoking dependence, number of daily smoked cigarettes, cannabis use, alcohol use or illness characteristics was found (all p > 0.05). CPI was associated with severe NIC dependence but not with tobacco smoking with low to moderate NIC dependence in SZ, independently of socio-demographic variables, body mass index, alcohol consumption and antidepressant intake. This result highlights the potential CPI consequences of the high prevalence of heavy tobacco smoking in SZ, indicating the importance of new therapeutic strategies for tobacco cessation in SZ.

C-reactive protein as an available biomarker determining mental component of health-related quality of life among individuals with spinal cord injury

OBJECTIVES

C-reactive protein (CRP) has been shown to correlate with health-related quality of life (HRQL) in some chronic medical conditions. However, these associations have not yet described in spinal cord injury (SCI). In this study, we tried to identify biomarkers associated with HRQL in SCI.

DESIGN

Cross-sectional.

SETTING

Tertiary rehabilitation center.

PARTICIPANTS

Referred patients to Brain and Spinal Cord Injury Research Center between November 2010 and April 2013.

OUTCOME MEASURE

Blood samples were taken to measure circulatory CRP, leptin, adiponectin, ferritin, parathyroid hormone, calcitonin, thyroid hormones, fasting plasma glucose and lipid profile. All the analyses were performed with adjustment for injury-related confounders (level of injury, injury completeness and time since injury) and demographic characteristics. HRQL was measured with Short Form health survey (SF-36).

RESULTS

The initial inverse association between CRP and total score of SF-36 (P: 0.006, r = -0.28) was lost after adjustment for confounders. However, the negative correlation between CRP and Mental Component Summary (MCS) remained significant (P: 0.0005, r = -0.38). Leptin level was inversely correlated with Physical Component Summary (PCS) (P: 0.02, r = -0.30).

CONCLUSION

Although CRP and leptin levels were not related with total scores of SF-36 questionnaire, CRP can be more useful in determining mental component of HRQL whereas leptin can be a determinant of physical component. The combined consideration of these two biomarkers may help to predict HRQL in individuals with SCI.

Associations between sleep quality and inflammatory markers in patients with schizophrenia

Sleep disorder is a risk factor for several systemic inflammation-related diseases and there are extensive data showing that schizophrenia is associated with chronic low-grade systemic inflammation. This study investigated the associations between sleep quality and inflammatory markers in patients with schizophrenia, which has not been examined before. Sleep quality (total sleep time, sleep efficiency, sleep onset latency, total activity counts, wake after sleep onset, number of awakening, and average length of awakening) was measured using actigraphy in 199 schizophrenia inpatients. The state of inflammation was measured using blood concentration of white blood cells (WBC) and neutrophils, together with neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio (PLR). The results showed that total sleep time was negatively associated with NLR and PLR, and sleep efficiency was negatively associated with neutrophil counts and NLR. Sleep onset latency, total activity counts, wake after sleep onset, and number of awakening were positively associated with WBC and neutrophil counts. The average length of awakening was positively associated with NLR and PLR. This is the first report to suggest that improving sleep quality may modulate the state of inflammation in patients with schizophrenia.

Self-reference in psychosis and depression: a language marker of illness

BACKGROUND

Language use is of increasing interest in the study of mental illness. Analytical approaches range from phenomenological and qualitative to formal computational quantitative methods. Practically, the approach may have utility in predicting clinical outcomes. We harnessed a real-world sample (blog entries) from groups with psychosis, strong beliefs, odd beliefs, illness, mental illness and/or social isolation to validate and extend laboratory findings about lexical differences between psychosis and control subjects.

METHOD

We describe the results of two experiments using Linguistic Inquiry and Word Count software to assess word category frequencies. In experiment 1, we compared word use in psychosis and control subjects in the laboratory (23 per group), and related results to subject symptoms. In experiment 2, we examined lexical patterns in blog entries written by people with psychosis and eight comparison groups. In addition to between-group comparisons, we used factor analysis followed by clustering to discern the contributions of strong belief, odd belief and illness identity to lexical patterns.

RESULTS

Consistent with others' work, we found that first-person pronouns, biological process words and negative emotion words were more frequent in psychosis language. We tested lexical differences between bloggers with psychosis and multiple relevant comparison groups. Clustering analysis revealed that word use frequencies did not group individuals with strong or odd beliefs, but instead grouped individuals with any illness (mental or physical).

CONCLUSIONS

Pairing of laboratory and real-world samples reveals that lexical markers previously identified as specific language changes in depression and psychosis are probably markers of illness in general.

Chronic Peripheral Inflammation is Associated With Cognitive Impairment in Schizophrenia: Results From the Multicentric FACE-SZ Dataset

OBJECTIVES

Inflammation, measured by abnormal blood C-reactive protein (CRP) level, has been described in schizophrenia (SZ), being inconsistently related to impaired cognitive functions. The aim of the present study is to investigate cognitive impairment associated with abnormal CRP levels in a large multi-centric sample of community-dwelling SZ patients, using a comprehensive neuropsychological battery.

METHOD

Three hundred sixty-nine community-dwelling stable SZ subjects (76.2% men, mean age 32.7 y) were included and tested with a comprehensive battery of neuropsychological tests. Abnormal CRP level was defined as >3mg/L.

RESULTS

Multiple factor analysis revealed that abnormal CRP levels, found in 104 patients (28.2%), were associated with impaired General Intellectual Ability and Abstract Reasoning (aOR = 0.56, 95% CI 0.35-0.90, P = .014), independently of age, sex, education level, psychotic symptomatology, treatments, and addiction comorbidities. Abnormal CRP levels were also associated with the decline of all components of working memory (respectively effect size [ES] = 0.25, P = .033; ES = 0.27, P = .04; ES = 0.33, P = .006; and ES = 0.38, P = .004) and a wide range of other impaired cognitive functions, including memory (ES = 0.26, P = .026), learning abilities (ES = 0.28, P = .035), semantic memory (ES = 0.26, P = .026), mental flexibility (ES = 0.26, P = .044), visual attention (ES = 0.23, P = .004) and speed of processing (ES = 0.23, P = .043).

CONCLUSION

Our results suggest that abnormal CRP level is associated with cognitive impairment in SZ. Evaluating the effectiveness of neuroprotective anti-inflammatory strategies is needed in order to prevent cognitive impairment in SZ.

Higher Plasma S100B Concentrations in Schizophrenia Patients, and Dependently Associated with Inflammatory Markers

Glial damage and immune dysfunction are involved in pathogenesis of schizophrenia. However, interaction between glial damage and immune dysfunction in schizophrenia is undefined. This study aims to compare plasma S100 calcium binding protein (S100B) levels between schizophrenia patients and healthy participants, and to determine if immune markers are independently related with concentration of S100B in schizophrenia patients. Forty-one schizophrenia patients and thirty-three healthy volunteers were enrolled. Enzyme-linked immunosorbent assay (ELISA) was used to assess the concentrations of plasma S100B and inflammatory markers. We found that concentrations of S100B were elevated in schizophrenia patients than healthy participants (p < 0.05), and were negatively related with the severity of symptoms (p = 0.046). Receiver operating characteristic (ROC) curve analysis showed that different S100B levels between schizophrenia and healthy participants can be used as a clinical diagnostic factor (predictive value: 0.666, p = 0.015). Multiple linear regression analysis found that length of illness (Beta = −0.161), plasma levels of inflammatory regulation factors (including TGF-β1, logIL-23 and logIL-10) (Beta = 0.119, 0.475, 0.514) were independently associated with concentrations of S100B (Adjusted R² = 0.897, p < 0.001). Therefore, our results suggest the possible function of S100B in pathogenesis of schizophrenia, and implicate the important role of autoimmune response and balance to glial dysfunction in patients with schizophrenia.