Paola Dazzan

King's College London | KCL · Department of Psychosis Studies

Background: Cannabis use has been linked to psychotic disorders but this association has been primarily observed in the Global North. This study investigates patterns of cannabis use and associations with psychoses in three Global South (regions within Latin America, Asia, Africa and Oceania) settings. Methods: Case-control study within the Inte...

Background and hypothesis: Treatment response to specific antipsychotic medications is difficult to predict on clinical grounds alone. The current study hypothesizes that the baseline complement pathway activity predicts the treatment response and investigates the relationship between baseline plasma biomarkers with treatment response to antipsych...

Background: Healthy, plant-based dietary patterns, particularly the Mediterranean diet (MD), have been associated with positive effect on mood symptoms and have been proposed to help prevent age-related cognitive decline. However,...

Background: Schizophrenia is a severe psychiatric disorder with periods of remission and relapse. As discontinuation of antipsychotic medication is the most important reason for relapse, long-term maintenance treatment is key. Whether intramuscular long-acting (depot) antipsychotics are more efficacious than oral medication in preventing medicatio...

Background: Although widely used, there is limited understanding on the suitability of different dietary assessment tools to estimate (poly)phenol intake. This study aims to compare the agreement between a food...

Introduction More than 1 in 10 people are thought to experience a mental health problem during adolescence, with most adult psychopathology beginning during this time. Experiences of stress or adversity during childhood are important risk factors for poorer mental health outcomes and are also associated with alterations in neurodevelopment. There i...

Frida Kahlo (1907-1954) was a Mexican artist who is remembered for her self-portraits, pain and passion, and bold, vibrant colours. This work aims to use her life story and her artistic production in a longitudinal study to examine with quantitative tools the effects of physical and emotional pain (rage) on artistic expression. Kahlo suffered from...

Normal and pathologic neurobiological processes influence brain morphology in coordinated ways that give rise to patterns of structural covariance (PSC) across brain regions and individuals during brain aging and brain diseases. The genetic underpinnings of these patterns remain largely unknown. We apply a stochastic multivariate factorization meth...

Background Postnatal depression (PND) affects 13% of new mothers, with numbers rising during the COVID-19 pandemic. Despite this prevalence, many women have difficulty with or hesitancy towards accessing pharmacological and/or psychological interventions. Group-based mother-baby activities, however, have a good uptake, with singing improving matern...

Maternal experiences of childhood adversity can increase the risk of emotional and behavioural problems in their children. This systematic review and meta-analysis provide the first narrative and quantitative synthesis of the mediators and moderators involved in the link between maternal childhood adversity and children's emotional and behavioural...

Autism spectrum disorder (ASD) is associated with high structural heterogeneity in magnetic resonance imaging (MRI). This work uncovers three neuroanatomical dimensions of ASD ( N =307) using machine learning methods and constructs their characteristic MRI signatures. The presence of these signatures, along with their clinical profiles and genetic...

Autism spectrum disorder (ASD) is associated with high structural heterogeneity in magnetic resonance imaging (MRI). This work uncovers three neuroanatomical dimensions of ASD ( N = 307) using machine learning methods and constructs their characteristic MRI signatures. The presence of these signatures, along with their clinical profiles and genetic...

Objective: The prevalence and significance of schizophrenia-related phenotypes at the population level is debated in the literature. Here, the authors assessed whether two recently reported neuroanatomical signatures of schizophrenia-signature 1, with widespread reduction of gray matter volume, and signature 2, with increased striatal volume-could...

Introduction Treatment-resistant schizophrenia (TRS) is associated with significant impairment of functioning and high treatment costs. Identification of patients at high risk of TRS at the time of their initial diagnosis may significantly improve clinical outcomes and minimise social and functional disability. We aim to develop a prognostic model...

Objective: Historically, assessment of the psychometric properties of the Positive and Negative Syndrome Scale (PANSS) has had several foci: 1) calculation of reliability indexes, 2) extraction of subdimensions from the scale, and 3) assessment of the validity of the total score. In this study, we aimed to examine the scalability and to assess the...

Studies that have used structural magnetic resonance imaging (MRI) suggest that individuals with psychoses have brain alterations, particularly in frontal and temporal cortices, and in the white matter tracts that connect them. Furthermore, these studies suggest that brain alterations may be particularly prominent, already at illness onset, in thos...

Importance: Previous in vitro and postmortem research suggests that inflammation may lead to structural brain changes via activation of microglia and/or astrocytic dysfunction in a range of neuropsychiatric disorders. Objective: To investigate the relationship between inflammation and changes in brain structures in vivo and to explore a transcri...

Left-right asymmetry is an important organizing feature of the healthy brain that may be altered in schizophrenia, but most studies have used relatively small samples and heterogeneous approaches, resulting in equivocal findings. We carried out the largest case-control study of structural brain asymmetries in schizophrenia, using MRI data from 5,08...

Background Negative symptoms are one of the most incapacitating features of Schizophrenia but their pathophysiology remains unclear. They have been linked to alterations in grey matter in several brain regions, but findings have been inconsistent. This may reflect the investigation of relatively small patient samples, and the confounding effects of...

Women with a schizophrenia-spectrum disorder (SSD) have a better clinical profile than do men at the start of their illness but progress to the same state within the first few years of living with SSD. There are benefits to be gained across different areas in the care currently offered to women with psychosis. An important point for improvement is...

Background Evidence suggests that cognitive subtypes exist in schizophrenia that may reflect different neurobiological trajectories. We aimed to identify whether IQ-derived cognitive subtypes are present in early-phase schizophrenia-spectrum disorder and examine their relationship with brain structure and markers of neuroinflammation. Method 161 p...

Introduction Treatment Resistant Schizophrenia (TRS) is associated with significant impairment of functioning and high treatment costs. Identification of patients at high risk of TRS at their initial diagnosis may significantly improve clinical outcomes and minimize social and functional disability. We aim to develop a prognostic model for predicti...

Introduction: Research on the benefits of 'arts' interventions to improve individuals' physical, social and psychological well-being is growing, but evidence on implementation and scale-up into health and social care systems is lacking. This protocol reports the SHAPER-Implement programme (Scale-up of Health-Arts Programmes Effectiveness-Implement...

Few studies have comprehensively examined the profile of cognitive functioning in first episode psychosis patients throughout the lifespan, and from first episode to chronic stage. We assessed functioning in general and specific cognitive functions, comparing both schizophrenia (N = 64) and bipolar I (N = 19) patients to controls (N = 103). Partici...

The prevalence and significance of schizophrenia-related phenotypes at the population-level are debated in the literature. Here we assess whether two recently reported neuroanatomical signatures of schizophrenia, signature 1 with widespread reduction of gray matter volume and signature 2 with increased striatal volume, could be replicated in an ind...

The Enhancing NeuroImaging Genetics through Meta-Analysis copy number variant (ENIGMA-CNV) and 22q11.2 Deletion Syndrome Working Groups (22q-ENIGMA WGs) were created to gain insight into the involvement of genetic factors in human brain development and related cognitive, psychiatric and behavioral manifestations. To that end, the ENIGMA-CNV WG has...

Postpartum psychosis is the most severe psychiatric disorder associated with childbirth, and the risk is particularly high for women with a history of bipolar disorder or schizoaffective disorder or those who have suffered a previous episode of postpartum psychosis. However, it remains unclear why some women at risk become unwell after giving birth...

Postpartum psychosis is the most severe perinatal mental health problem and a psychiatric and obstetric emergency. It can result in considerable distress, and may have long-term consequences for women’s well-being, as well as that of their baby and their family, together with implications for wider society. Clinical characteristics of the illness i...

Introduction: Postnatal depression (PND) affects approximately 13% of new mothers. Community-based activities are sought after by many mothers, especially mothers that prefer not to access pharmacological or psychological interventions. Singing has shown positive effects in maternal mood and mother-child bonding. The Scaling-Up Health-Arts Program...

There are significant differences between men and women in the efficacy and tolerability of antipsychotic drugs. Here, we provide a comprehensive overview of what is currently known about the pharmacokinetics and pharmacodynamics of antipsychotics in women with schizophrenia spectrum disorders (SSDs) and translate these insights into considerations...

Disease heterogeneity is a significant obstacle to understanding pathological processes and delivering precision diagnostics and treatment. Clustering methods have gained popularity for stratifying patients into subpopulations (i.e., subtypes) of brain diseases using imaging data. However, unsupervised clustering approaches are often confounded by...

Inflammatory processes in the Central Nervous System (CNS) have been proposed to mediate the association between peripheral inflammation and the development of psychiatric disorders, but we currently lack sensitive measures of CNS inflammation for human studies in vivo. Here we used quantitative MRI (qMRI) to explore the in vivo central response to...

Background A history of childhood adversity is associated with psychotic disorder, with an increase in risk according to the number of exposures. However, it is not known why only some exposed individuals go on to develop psychosis. One possibility is pre-existing polygenic vulnerability. Here, we investigated, in the largest sample of first-episod...

Background We aimed to examine neonatal behaviour and cortisol reactivity in neonates born to women at risk of postpartum psychosis (AR) who had a psychiatric relapse within 4 weeks post-delivery (AR-unwell), compared with neonates of women at risk who stayed well (AR-well) and those born to healthy women (HC). Methods We assessed neonatal behavio...

Background Mental health disorders affect 1 in 10 people globally, of whom approximately 300 million are affected by depression. At least half of the people affected by depression remain untreated. Although cognitive behavioral therapy (CBT) is an effective treatment, access to mental health specialists, habitually challenging, has worsened because...

Machine learning classifications of first-episode psychosis (FEP) using neuroimaging have predominantly analyzed brain volumes. Some studies examined cortical thickness, but most of them have used parcellation approaches with data from single sites, which limits claims of generalizability. To address these limitations, we conducted a large-scale, m...

Background: Postpartum psychosis (PP) is the most severe psychiatric disorder associated with childbirth. However, there is little research on maternal bonding towards the infant and parenting stress in this clinical population. Methods: We investigated maternal bonding during pregnancy and post-partum in 75 women: 46 at risk of PP (AR), because of...

Background: Overgeneralised self-blaming emotions, such as self-disgust, are core symptoms of major depressive disorder (MDD) and prompt specific actions (i.e. "action tendencies"), which are more functionally relevant than the emotions themselves. We have recently shown, using a novel cognitive task, that when feeling self-blaming emotions, malad...

Background Patients with a First-Episode of Psychosis (FEP) exhibit low-grade inflammation as demonstrated by elevated levels of C reactive protein (CRP) and pro-inflammatory cytokines. Aims The primary goal of this study was to investigate the association between pro-inflammatory biomarkers and clinical outcomes in unmedicated FEP patients. Meth...

Postpartum psychosis (PP) is a severe mental disorder that affects women in the first few weeks after delivery. To date there are no biomarkers that distinguish which women at risk (AR) develop a significant psychiatric relapse postpartum. While altered brain connectivity may contribute to the risk for psychoses unrelated to the puerperium, this re...

Background: No study investigated the association between stress exposure in different stages of life and metabolic dysfunction. Aim: We explore the association between stress exposure and several biomarkers related to glucose metabolism (insulin, c-peptide, GIP, GLP-1, glucagon) in a group of 72 healthy individuals. Method: We used the Childhood E...

Background Little is known about the effects of depression before birth on the quality of the mother–infant interaction. Aims To understand whether depression, either in pregnancy or in lifetime before pregnancy, disrupts postnatal mother–infant interactions. Method We recruited 131 pregnant women (51 healthy, 52 with major depressive disorder (M...

Treatment resistance (TR) in patients with first-episode psychosis (FEP) is a major cause of disability and functional impairment, yet mechanisms underlying this severe disorder are poorly understood. As one view is that TR has neurodevelopmental roots, we investigated whether its emergence relates to disruptions in synchronized cortical mat-uratio...

Background Postpartum psychosis is the most severe psychiatric disorder associated with childbirth, and the risk is particularly high for women with a history of bipolar disorder, schizoaffective disorder or those who have suffered a previous episode of postpartum psychosis. Whilst there is a lot of evidence linking stress to psychosis unrelated to...

Background Sex hormones and the immune system may play a key role in sex differences in affective disorders. The understanding of their interplay may lead to the detection of new sex-specific tailored therapeutic approaches. The aim of this systematic review is to summarise the evidence supporting a possible association between sex hormones and inf...

Persistent negative symptoms are associated with worse outcome in both first-episode and chronic subjects with schizophrenia. The identification of these symptoms in recent-onset subjects is still controversial as retrospective data are often unavailable. The prospective assessment of persistence of negative symptoms might represent a valid alterna...

Low-frequency 1q21.1 distal deletion and duplication copy number variant (CNV) carriers are predisposed to multiple neurodevelopmental disorders, including schizophrenia, autism and intellectual disability. Human carriers display a high prevalence of micro- and macrocephaly in deletion and duplication carriers, respectively. The underlying brain st...

The Enhancing NeuroImaging Genetics through Meta‐Analysis copy number variant (ENIGMA‐CNV) and 22q11.2 Deletion Syndrome Working Groups (22q‐ENIGMA WGs) were created to gain insight into the involvement of genetic factors in human brain development and related cognitive, psychiatric and behavioral manifestations. To that end, the ENIGMA‐CNV WG has...

Promising research investigating the association between inflammatory biomarkers and response to antipsychotic and/or adjunctive therapy, observed by improvement in psychiatric assessment, is emerging. Increased inflammation has been suggested to contribute to higher severity of symptoms/treatment resistance through the effects that this has on bra...

Recent findings implicate the complement C4 gene in gray matter loss in schizophrenia. In a large cohort of patients with first episode psychosis (FEP) we aimed to i) characterize the frequency of C4 gene copy number variations (CNVs) and HERV-K Ins/Del events as compared to that in healthy controls (HC), ii) evaluate whether C4 gene structural var...

Background The clinical course of psychotic disorders is highly variable. Typically, researchers have captured different course types using broad pre-defined categories. However, whether these adequately capture symptom trajectories of psychotic disorders has not been fully assessed. Using data from AESOP-10, we sought to identify classes of indivi...

Low-frequency 1q21.1 distal deletion and duplication copy number variant (CNV) carriers are predisposed to multiple neurodevelopmental disorders including schizophrenia, autism and intellectual disability. Human carriers display a high prevalence of micro- and macrocephaly in deletion and duplication carriers, respectively. The underlying brain str...

Background- Overgeneralised self-blaming emotions, such as self-disgust, are core symptoms of major depressive disorder (MDD) and prompt specific actions (i.e. "action tendencies"), which are more functionally relevant than the emotions themselves. We have recently shown, using a novel cognitive task, that when feeling self-blaming emotions, malada...

The Enhancing Neuroimaging Genetics through Meta-Analysis copy number variant (ENIGMA-CNV) and 22q11.2 Deletion Syndrome Working Groups (22q-ENIGMA WGs) were created to gain insight into the involvement of genetic factors in human brain development and related cognitive, psychiatric and behavioral manifestations. To that end, the ENIGMA-CNV WG has...

The Scaling-up Health-Arts Programme: Implementation and Effectiveness Research (SHAPER) project is the world's largest hybrid study on the impact of the arts on mental health embedded into a national healthcare system. This programme, funded by the Wellcome Trust, aims to study the impact and the scalability of the arts as an intervention for ment...

Evidence suggests there are two treatment-resistant schizophrenia subtypes (i.e. early treatment resistant (E-TR) and late-treatment resistant (L-TR)). We aimed to develop prediction models for estimating individual risk for these outcomes by employing advanced statistical shrinkage methods. 239 first-episode schizophrenia (FES) patients were follo...

Background Immune dysfunction has been implicated in negative symptoms of schizophrenia and also in depression. These disorders are frequently co-morbid, with some symptoms such as anhedonia and apathy common to both. The anti-inflammatory agent minocycline may be ineffective in schizophrenia, but more positive effects have been seen in depression....

Background When psychosis develops in NMDAR antibody encephalitis it usually has an acute or subacute onset, and antipsychotic treatment may be ineffective and associated with adverse effects. Serum NMDAR antibodies have been reported in a minority of patients with first episode psychosis (FEP), but their role in psychosis onset and response to ant...

To clarify the involvement of the cerebellum in impaired sensory integration in patients with schizophrenia, 52 first-episode patients with schizophrenia and 52 age- and sex-matched healthy controls underwent a verified sensory integration imaging task to examine the whole-brain dysfunction underlying impaired sensory integration. The familiality o...

Individuals with psychoses have brain alterations, particularly in frontal and temporal cortices, that may be particularly prominent, already at illness onset, in those more likely to have poorer symptom remission following treatment with the first antipsychotic. The identification of strong neuroanatomical markers of symptom remission could thus f...

The ability to identify biomarkers of psychosis risk is essential in defining effective preventive measures to potentially circumvent the transition to psychosis. Using samples of people at clinical high risk for psychosis (CHR) and Healthy controls (HC) who were administered a task fMRI paradigm, we used a framework for labelling time windows of f...

Background: Individuals diagnosed with schizophrenia are often assigned other psychiatric diagnoses during their lives. The significance of changing diagnosis has not been widely studied. Aims: Our aim was to examine the association between diagnostic change and later outcome. Methods: Individuals' diagnostic history, clinical and social outco...

Background A growing body of research suggests that childhood adversities are associated with later psychosis, broadly defined. However, there remain several gaps and unanswered questions. Most studies are of low-level psychotic experiences and findings cannot necessarily be extrapolated to psychotic disorders. Further, few studies have examined th...