Do schizophrenia patients age early?

Subjective Overview of Accelerated Aging in Schizophrenia

Schizophrenia, like many other human diseases, particularly neuropsychiatric diseases, shows evidence of accelerated brain aging. The molecular nature of the process of aging is unknown but several potential indicators have been used in research. The concept of accelerated aging in schizophrenia took hold in 2008 and its timing, pace, determinants and deterrents have been increasingly examined since. The present overview of the field is brief and selective, based on diverse studies, expert opinions and successive reviews. Current thinking is that the timing of age acceleration in schizophrenia can occur at different time periods of the lifespan in different individuals, and that antipsychotics may be preventive. The majority opinion is that the cognitive decline and premature death often seen in schizophrenia are, in principle, preventable.

Telomere Length as a Marker of Suicidal Risk in Schizophrenia

BACKGROUND

Schizophrenia and suicidal behavior are associated with shortening in the length of telomeres. The aim of the study was to compare the content (pg/mcg) of telomeric repeat in DNA isolated from peripheral blood cells in three groups of subjects: patients with schizophrenia and a history of suicide attempts, patients with schizophrenia without suicidal tendencies, and healthy control volunteers.

METHODS

Relapses according to gender and age were examined in 47 patients with schizophrenia with suicidal behavior, 47 patients without self-destructive conditions, and 47 volunteers with healthy control and maintenance for the content of telomeric and the number of copies of mitochondrial DNA (mtDNA) in peripheral blood leukocytes.

RESULTS

Analysis of determining the content of telomeric repeat (TR) in the DNA of massive weight gain in the series: patients with schizophrenia and suicidal attempts - patients with schizophrenia without suicidal observations - healthy controls (225±28.4 (227 [190; 250]) vs. 243±21 (245 [228; 260]) vs. 255±17.9 (255 [242; 266]), p <0.005. The same trend is observed for the number of mtDNA copies (257±101.5 (250 [194; 297])) vs. 262.3±59.3 (254 [217; 312]) vs. 272±79.9 (274 [213; 304]); p=0.012), but no significant differences were recorded.

CONCLUSIONS

For the first time, the phenomenon of telomere shortening was discovered in schizophrenics with suicidal risk. The length of the telomere corresponds to the parameter of a biological marker - an objectively measured indicator of normal or pathological processes, but gaining an idea of its reliability is still necessary for verification with an assessment of its sensitivity, specificity, and positive and negative predictive value. The telomere may be considered a putative predictive indicator of suicidal risk.

Frailty among inpatients with Schizophrenia: Status, influencing factors, and their correlation with quality of life

OBJECTIVE

This study aimed to understand frailty and its influencing factors in inpatients with Schizophrenia in Chengdu and to explore correlations between frailty and quality of life.

METHODS

From May to July 2022, inpatients with Schizophrenia were surveyed using a general information questionnaire, frailty phenotype (FP) scoring, the Self-Rating Depression Scale (SDS), the Mini-Mental State Examination (MMSE), and the SZ Quality of Life Scale (SQLS). Multivariate logistic regression was conducted to assess factors influencing frailty and multivariate linear regression was conducted to assess the factors influencing quality of life.

RESULTS

A total of 556 hospitalized patients with Schizophrenia were included and divided into three groups according to the degree of frailty, of which 153 cases (27.5%) were without frailty, 348 cases (62.6%) were in early frailty, and 55 cases (9.9%) were in frailty. Univariate analysis of age, history of falls during hospitalization, polypharmacy, compulsory treatment during hospitalization, self-reported health status, activity level, cognitive impairment, depressive symptoms, "psychology and society," "motivation and energy" and "symptoms and side-effects" showed statistically significant differences between the groups. Multinomial logistic regression showed that age, BMI, self-reported health, activity, cognitive impairment, motivation and energy, and symptoms and side-effects were influencing factors for frailty in hospitalized patients with Schizophrenia. Correlation analysis shows that frailty score positively correlated with SQLS score.

CONCLUSION

We found that frailty was prevalent and that frailty was positively correlated with SQLS scores in inpatients with Schizophrenia. To effectively manage the frailty of hospitalized patients with Schizophrenia, medical staff should pay attention to its influencing factors and quality of life.

Brain Versus Blood: A Systematic Review on the Concordance Between Peripheral and Central Kynurenine Pathway Measures in Psychiatric Disorders

Objective

Disturbances in the kynurenine pathway have been implicated in the pathophysiology of psychotic and mood disorders, as well as several other psychiatric illnesses. It remains uncertain however to what extent metabolite levels detectable in plasma or serum reflect brain kynurenine metabolism and other disease-specific pathophysiological changes. The primary objective of this systematic review was to investigate the concordance between peripheral and central (CSF or brain tissue) kynurenine metabolites. As secondary aims we describe their correlation with illness course, treatment response, and neuroanatomical abnormalities in psychiatric diseases.

Methods

We performed a systematic literature search until February 2021 in PubMed. We included 27 original research articles describing a correlation between peripheral and central kynurenine metabolite measures in preclinical studies and human samples from patients suffering from neuropsychiatric disorders and other conditions. We also included 32 articles reporting associations between peripheral KP markers and symptom severity, CNS pathology or treatment response in schizophrenia, bipolar disorder or major depressive disorder.

Results

For kynurenine and 3-hydroxykynurenine, moderate to strong concordance was found between peripheral and central concentrations not only in psychiatric disorders, but also in other (patho)physiological conditions. Despite discordant findings for other metabolites (mainly tryptophan and kynurenic acid), blood metabolite levels were associated with clinical symptoms and treatment response in psychiatric patients, as well as with observed neuroanatomical abnormalities and glial activity.

Conclusion

Only kynurenine and 3-hydroxykynurenine demonstrated a consistent and reliable concordance between peripheral and central measures. Evidence from psychiatric studies on kynurenine pathway concordance is scarce, and more research is needed to determine the validity of peripheral kynurenine metabolite assessment as proxy markers for CNS processes. Peripheral kynurenine and 3-hydroxykynurenine may nonetheless represent valuable predictive and prognostic biomarker candidates for psychiatric disorders.

Challenges in Prescribing Clozapine in the Era of COVID-19: A Review Focused on Immunological Implications

The global COVID-19 pandemic has disrupted every aspect of the healthcare system. Apart from the issues surrounding COVID-19 itself, care for existing patients has met many challenges. One such challenge is caring for patients who are on clozapine treatment and have been confirmed positive for COVID-19. Schizophrenia has been considered to have a deep connection with the immune system, and clozapine can induce further changes in this system. COVID-19 can ravage the compromised immune system and aggravate tissue damage. The intricate relations between schizophrenia, clozapine, and COVID-19 make it difficult to predict the clinical course of COVID-19 in clozapine-treated patients. However, the rigid prohibition on using clozapine if COVID-19 is confirmed may harm patients. Patients who have to use clozapine are often refractory cases with no alternatives. Therefore, the decision to maintain or stop clozapine must be made after a comprehensive review of the patient’s unique situation. To do this, theoretical and practical issues surrounding the use of clozapine in COVID-19 should be reviewed and discussed. In this review, we gather useful information surrounding this issue and present an overview. Focusing on the immune system, various theoretical possibilities that could arise from schizophrenia, clozapine, and COVID-19 were carefully examined, and practical checklists for the care of these patients were explored. It is hoped that this review will convince many clinicians to pay attention to this momentous issue and facilitate more active sharing of clinical experiences.

Accelerated aging in the brain, epigenetic aging in blood, and polygenic risk for schizophrenia

Schizophrenia patients show signs of accelerated aging in cognitive and physiological domains. Both schizophrenia and accelerated aging, as measured by MRI brain images and epigenetic clocks, are correlated with increased mortality. However, the association between these aging measures have not yet been studied in schizophrenia patients. In schizophrenia patients and healthy subjects, accelerated aging was assessed in brain tissue using a longitudinal MRI (N = 715 scans; mean scan interval 3.4 year) and in blood using two epigenetic age clocks (N = 172). Differences ('gaps') between estimated ages and chronological ages were calculated, as well as the acceleration rate of brain aging. The correlations between these aging measures as well as with polygenic risk scores for schizophrenia (PRS; N = 394) were investigated. Brain aging and epigenetic aging were not significantly correlated. Polygenic risk for schizophrenia was significantly correlated with brain age gap, brain age acceleration rate, and negatively correlated with DNAmAge gap, but not with PhenoAge gap. However, after controlling for disease status and multiple comparisons correction, these effects were no longer significant. Our results imply that the (accelerated) aging observed in the brain and blood reflect distinct biological processes. Our findings will require replication in a larger cohort.

Leukocyte mitochondrial DNA copy number in schizophrenia

OBJECTIVE

Schizophrenia is a complex neuropsychiatric disorder with significant genetic predisposition. In a subset of schizophrenia patients, mitochondrial dysfunction could be explained by the genomic defects like mitochondrial DNA Copy Number Variations, which are considered as a sensitive index of cellular oxidative stress. Given the high energy demands for neuronal functions, altered Mitochondrial DNA copy number (mtDNAcn) and consequent impaired mitochondrial physiology would significantly influence schizophrenia pathogenesis. In this context, we have made an attempt to study mitochondrial dysfunction in schizophrenia by assessing mtDNAcn in antipsychotic-naïve/free schizophrenia patients.

METHOD

mtDNAcn was measured in 90 antipsychotic-naïve / free schizophrenia (SCZ) patients and 147 Healthy Controls (HC). The relative mtDNAcn was determined by quantitative real-time polymerase chain reaction (qPCR) using TaqMan® multiplex assay method.

RESULT

A statistically significant difference between groups [t = 5.22, P < 0.001] was observed, with significantly lower mtDNAcn in SCZ compared to HC. The group differences persisted even after controlling for age and sex [F (4, 232) = 22.68, P < 0.001, η2 = 0.09].

CONCLUSION

Lower mtDNAcn in SCZ compared to HC suggests that mtDNAcn may hold potential to serve as an important proxy marker of mitochondrial function in antipsychotic-naïve/free SCZ patients.

Enhanced Molecular Appreciation of Psychiatric Disorders Through High-Dimensionality Data Acquisition and Analytics

The initial diagnosis, molecular investigation, treatment, and posttreatment care of major psychiatric disorders (schizophrenia and bipolar depression) are all still significantly hindered by the current inability to define these disorders in an explicit molecular signaling manner. High-dimensionality data analytics, using large datastreams from transcriptomic, proteomic, or metabolomic investigations, will likely advance both the appreciation of the molecular nature of major psychiatric disorders and simultaneously enhance our ability to more efficiently diagnose and treat these debilitating conditions. High-dimensionality data analysis in psychiatric research has been heterogeneous in aims and methods and limited by insufficient sample sizes, poorly defined case definitions, methodological inhomogeneity, and confounding results. All of these issues combine to constrain the conclusions that can be extracted from them. Here, we discuss possibilities for overcoming methodological challenges through the implementation of transcriptomic, proteomic, or metabolomics signatures in psychiatric diagnosis and offer an outlook for future investigations. To fulfill the promise of intelligent high-dimensionality data-based differential diagnosis in mental disease diagnosis and treatment, future research will need large, well-defined cohorts in combination with state-of-the-art technologies.

Telomere length and its association with hippocampal gray matter volume in antipsychotic-naïve/free schizophrenia patients

Accelerated ageing processes are postulated to underlie schizophrenia pathogenesis. This postulate is supported by observations of reduced telomere length in schizophrenia patients. Hippocampus, one of the most important brain regions implicated in schizophrenia, is shown to atrophy at a faster rate in aging. In this study, telomere length (TL) was measured in 30 antipsychotic-naive/free schizophrenia patients and 60 healthy controls using quantitative PCR assay. Hippocampus volume was measured using voxel-based morphometry. Schizophrenia was associated with differential TL between sexes [Status × Sex; F(1,85) = 5.9, p = 0.017, η² = 0.065]. Male schizophrenia patients had significantly lower relative TL than female patients [F(1,85) = 7.38, p = 0.008], while such sex difference was not observed in healthy controls [F(1,85) = 0.16, p = 0.69]. Schizophrenia patients showed a significant sex-by-telomere interaction with both right & left hippocampus, with male patients showing positive association of telomere length with volume, while female patients showed negative association. Telomere shortening and the positive association of telomere length with hippocampus volume was observed only in male patients with schizophrenia. Since correlational observations in this cross-sectional study does not necessarily support definitive causal relationship, further longitudinal studies examining hippocampus volume and telomere in schizophrenia patients are needed.

Systemic Biomarkers of Accelerated Aging in Schizophrenia: A Critical Review and Future Directions

BACKGROUND

Schizophrenia is associated with increased physical morbidity and early mortality, suggesting that the aging process may be accelerated in schizophrenia. However, the biological underpinnings of these alterations in aging in schizophrenia are unclear.

METHOD

We conducted a detailed search of peer-reviewed empirical studies to evaluate evidence for accelerated biological aging in schizophrenia based on systemic, age-related biomarkers. We included studies that investigated differences between persons with schizophrenia and healthy comparison subjects in levels of biomarkers known to be associated with aging and examined the relationship of these biomarkers to age in the 2 groups.

RESULTS

Forty-two articles that met our selection criteria were reviewed. Nearly 75% reported abnormal biomarker levels among individuals with schizophrenia, including indices of inflammation, cytotoxicity, oxidative stress, metabolic health, gene expression, and receptor/synaptic function, with medium to large effect sizes reported in many studies. Twenty-nine percent of the studies observed differential age-related decline in schizophrenia. Markers of receptor/synaptic function and gene expression were most frequently differentially related to age in schizophrenia. Schizophrenia patients with greater disease severity and longer illness duration exhibited higher levels of inflammatory and oxidative stress biomarkers and shorter telomere length.

CONCLUSIONS

Most studies show biomarker abnormalities in schizophrenia, and there is some suggestion for accelerated aging. Although definitive interpretation is limited by cross-sectional design of the published reports, findings in the area of gene expression and synaptic function are promising and pave the way for future longitudinal studies needed to fully test this hypothesis.

Vitamin D deficiency: infertility and neurodevelopmental diseases (attention deficit hyperactivity disorder, autism, and schizophrenia)

The process of development depends on a number of signaling systems that regulates the progressive sequence of developmental events. Infertility and neurodevelopmental diseases, such as attention deficit hyperactivity disorder, autism spectrum disorders, and schizophrenia, are caused by specific alterations in these signaling processes. Calcium signaling plays a prominent role throughout development beginning at fertilization and continuing through early development, implantation, and organ differentiation such as heart and brain development. Vitamin D plays a major role in regulating these signaling processes that control development. There is an increase in infertility and an onset of neurodevelopmental diseases when vitamin D is deficient. The way in which vitamin D deficiency acts to alter development is a major feature of this review. One of the primary functions of vitamin D is to maintain the phenotypic stability of both the Ca²⁺ and redox signaling pathways that play such a key role throughout development.

Leukocyte telomere length: Effects of schizophrenia, age, and gender

BACKGROUND

Schizophrenia is linked with early medical comorbidity and mortality. These observations indicate possible "accelerated biological aging" in schizophrenia, although prior findings are mixed, and few such studies have examined the role of gender. One putative marker of biological aging is leukocyte telomere length (LTL), which typically shortens with age.

METHODS

We assessed LTL in phenotypically well characterized 134 individuals with schizophrenia (60 women and 74 men) and 123 healthy comparison subjects (HCs) (66 women and 57 men), aged 26 to 65 years.

RESULTS

Overall, LTL was inversely associated with age (t(249) = -6.2, p < 0.001), and a gender effect on the rate of LTL decrease with age was found (t(249) = 2.20, p = 0.029), with men declining more rapidly than women. No significant overall effect of diagnosis on the rate of decline was detected. However, at the average sample age (48 years), there was a significant gender effect in both schizophrenia and HC groups (t(249) = 2.48, p = 0.014), with women having longer LTL than men, and a significant gender X diagnosis effect (t(249) = 2.43, p = 0.016) - at the average sample age, women with schizophrenia had shorter LTL than HC women.

DISCUSSION

Gender, not the diagnosis of schizophrenia, was the major factor involved with LTL shortening across the age range studied. We discuss the constraints of a cross-sectional design and other methodological issues, and indicate future directions. Understanding the impact of schizophrenia on biological aging will require separate evaluations in men and women.

Human dermal fibroblasts in psychiatry research

In order to decipher the disease etiology, progression and treatment of multifactorial human brain diseases we utilize a host of different experimental models. Recently, patient-derived human dermal fibroblast (HDF) cultures have re-emerged as promising in vitro functional system for examining various cellular, molecular, metabolic and (patho)physiological states and traits of psychiatric disorders. HDF studies serve as a powerful complement to postmortem and animal studies, and often appear to be informative about the altered homeostasis in neural tissue. Studies of HDFs from patients with schizophrenia (SZ), depression, bipolar disorder (BD), autism, attention deficit and hyperactivity disorder and other psychiatric disorders have significantly advanced our understanding of these devastating diseases. These reports unequivocally prove that signal transduction, redox homeostasis, circadian rhythms and gene*environment (G*E) interactions are all amenable for assessment by the HDF model. Furthermore, the reported findings suggest that this underutilized patient biomaterial, combined with modern molecular biology techniques, may have both diagnostic and prognostic value, including prediction of response to therapeutic agents.

Can cognitive behaviour therapy beneficially influence arousal mechanisms in psychosis?

Cognitive behavioural therapy for psychosis (CBTp) is an approved adjunct therapy for patients with psychotic disorders; however, we do not fully understand the neurobiological effects that this therapy may exert. Arousal, as measured by electroencephalography (EEG), provides a useful electrophysiological marker for assessing psychotic disorders. EEG studies may therefore serve as a useful measure for assessing the underlying effects of CBTp in psychotic disorders.

Psychiatric disorders and leukocyte telomere length: Underlying mechanisms linking mental illness with cellular aging

Many psychiatric illnesses are associated with early mortality and with an increased risk of developing physical diseases that are more typically seen in the elderly. Moreover, certain psychiatric illnesses may be associated with accelerated cellular aging, evidenced by shortened leukocyte telomere length (LTL), which could underlie this association. Shortened LTL reflects a cell's mitotic history and cumulative exposure to inflammation and oxidation as well as the availability of telomerase, a telomere-lengthening enzyme. Critically short telomeres can cause cells to undergo senescence, apoptosis or genomic instability, and shorter LTL correlates with poorer health and predicts mortality. Emerging data suggest that LTL may be reduced in certain psychiatric illnesses, perhaps in proportion to exposure to the psychiatric illnesses, although conflicting data exist. Telomerase has been less well characterized in psychiatric illnesses, but a role in depression and in antidepressant and neurotrophic effects has been suggested by preclinical and clinical studies. In this article, studies on LTL and telomerase activity in psychiatric illnesses are critically reviewed, potential mediators are discussed, and future directions are suggested. A deeper understanding of cellular aging in psychiatric illnesses could lead to re-conceptualizing them as systemic illnesses with manifestations inside and outside the brain and could identify new treatment targets.

Physical Exercise Alleviates Health Defects, Symptoms, and Biomarkers in Schizophrenia Spectrum Disorder

Schizophrenia spectrum disorders are characterized by symptom profiles consisting of positive and negative symptoms, cognitive impairment, and a plethora of genetic, epigenetic, and phenotypic biomarkers. Assorted animal models of these disorders and clinical neurodevelopmental indicators have implicated neurodegeneration as an element in the underlying pathophysiology. Physical exercise or activity regimes--whether aerobic, resistance, or endurance--ameliorate regional brain and functional deficits not only in affected individuals but also in animal models of the disorder. Cognitive deficits, often linked to regional deficits, were alleviated by exercise, as were quality-of-life, independent of disorder staging and risk level. Apoptotic processes intricate to the etiopathogenesis of schizophrenia were likewise attenuated by physical exercise. There is also evidence of manifest benefits endowed by physical exercise in preserving telomere length and integrity. Not least, exercise improves overall health and quality-of-life. The notion of scaffolding as the outcome of physical exercise implies the "buttressing" of regional network circuits, neurocognitive domains, anti-inflammatory defenses, maintenance of telomeric integrity, and neuro-reparative and regenerative processes.

Leukocyte telomere length in patients with schizophrenia: A meta-analysis

Schizophrenia has been suggested as a syndrome of accelerated aging. Telomere length (TL) decrease is considered one biological marker associated with age and can be accelerated by pathological characteristics present in schizophrenia. Several studies evaluated TL in schizophrenia, but the results are still controversial. The aim of this study was to conduct a meta-analysis of the existing results of TL in leukocytes of individuals with schizophrenia compared to healthy controls. A search was performed in PubMed, using the keywords 'telomere schizophrenia' and 'telomere psychosis'. We included data from original articles that measured TL in leukocytes of human patients with schizophrenia and healthy control subjects. 45 articles were found, but only 7 met our criteria. Telomere length of controls was not statistically different from that of patients with schizophrenia (p=0.07). Crossvalidation with the leave-one-out method resulted in a significant model (p=0.03) in which TL of individuals with schizophrenia is smaller than control (SMD=0.38; 95% CI=[0.05, 0.72]). We also propose a biological pathway through which schizophrenia could promote telomere erosion and how antipsychotics might compensate this loss. There are few studies made on this subject with diverse methodology and heterogeneous sample. Some articles did not consider other possible influences on TL. Overall our results suggest that TL is decreased in schizophrenia. Although this is consistent with the idea of accelerated aging, schizophrenia is a complex disease and there are several factors that influence TL that should be controlled in future studies.

Genetics of aging, health, and survival: dynamic regulation of human longevity related traits

Background: The roles of genetic factors in human longevity would be better understood if one can use more efficient methods in genetic analyses and investigate pleiotropic effects of genetic variants on aging and health related traits.

Data and methods: We used EMMAX software with modified correction for population stratification to perform genome wide association studies (GWAS) of female lifespan from the original FHS cohort. The male data from the original FHS cohort and male and female data combined from the offspring FHS cohort were used to confirm findings. We evaluated pleiotropic effects of selected genetic variants as well as gene-smoking interactions on health and aging related traits. Then we reviewed current knowledge on functional properties of genes related to detected variants.

Results: The eight SNPs with genome-wide significant variants were negatively associated with lifespan in both males and females. After additional QC, two of these variants were selected for further analyses of their associations with major diseases (cancer and CHD) and physiological aging changes. Gene-smoking interactions contributed to these effects. Genes closest to detected variants appear to be involved in similar biological processes and health disorders, as those found in other studies of aging and longevity e.g., in cancer and neurodegeneration.

Conclusions: The impact of genes on longevity may involve trade-off-like effects on different health traits. Genes that influence lifespan represent various molecular functions but may be involved in similar biological processes and health disorders, which could contribute to genetic heterogeneity of longevity and the lack of replication in genetic association studies.