Autistic and Schizotypal Traits and Global Functioning in Bipolar Disorder

Background and Aims To determine the expression of autistic and positive schizotypal traits in a large sample of adults with bipolar disorder (BD), and the effect of co-occurring autistic and positive schizotypal traits on global functioning in BD. Methods Autistic and positive schizotypal traits were assessed in 797 individuals with BD recruited by the Bipolar Disorder Research Network (BDRN), using the Autism-Spectrum Quotient and Kings Schizotypy Questionnaire (KSQ), respectively. Differences in global functioning (rated using the Global Assessment Scale) during lifetime worst depressive and manic episodes (GASD and GASM respectively) were calculated in groups with high/low autistic and positive schizotypal traits. Regression analyses assessed the interactive effect of autistic and positive schizotypal traits on global functioning. Results 47.2% (CI = 43.7–50.7%) showed clinically significant levels of autistic traits. Mean of sample on the KSQ-Positive scale was 11.98 (95% CI: 11.33–12.62). In the worst episode of mania, the high autistic, high positive schizotypal group had better global functioning than the low autistic, low positive schizotypal group (mean difference = 3.72, p = 0.004). High levels of co-occurring traits were associated with better global functioning in both mood states in individuals with a history of psychosis (GASM: p < 0.001; GASD: p = 0.055). Conclusions Expression of autistic and schizotypal traits in adults with BD is prevalent, and may be important to predict course of illness, prognosis, and in devising individualised therapies. Future work should focus on replicating these findings in independent samples, and on the biological and/or psychosocial mechanisms underlying better global functioning in those who have high levels of both autistic and positive schizotypal traits.

Mania Triggered by Sleep Loss: Implications for Postpartum Psychosis

Background and Aims To examine whether a history of mood episodes triggered by sleep loss is associated with (1) postpartum psychosis (PP) and (2) more broadly-defined postpartum mood episodes that included postnatal depression (PND), in women with bipolar disorder (BD). Methods Participants were 622 parous women with a diagnosis of bipolar-I disorder recruited in the UK to the Bipolar Disorder Research Network. Diagnosis and perinatal episodes were assessed via interview and case note data. Women were also asked during the interview whether episodes of mania and/or depression were triggered by sleep loss. We compared the rates of PP and PND within women who did and did not endorse sleep loss as a trigger of mood episodes. Results Women who reported that their episodes of mania were usually triggered by sleep loss were twice as likely to have experienced an episode of PP (OR = 2.00, 95% CI = 1.20–3.36) than women who did not report this. This effect remained significant when controlling for clinical and demographic factors. We found no significant associations between depression triggered by sleep loss and PP. Analyses in which we defined postpartum episodes at a broader level to include both PP and PND were not significant. Conclusions In pregnant women with BD, a history of mania following sleep loss could be a potential marker of vulnerability to severe postpartum episodes. Further study in prospective samples is required in order to confirm these findings, which may have important implications for understanding the aetiology of PP and of mood disorders more generally.

Polygenic Interactions with Environmental Adversity in the Aetiology of Major Depressive Disorder

Major depressive disorder (MDD) is a common and disabling condition with well-established heritability and environmental risk factors. Gene–environment interaction studies in MDD have typically investigated candidate genes, though the disorder is known to be highly polygenic. This study aims to test for interaction between polygenic risk and stressful life events (SLEs) or childhood trauma (CT) in the aetiology of MDD. The RADIANT UK sample consists of 1605 MDD cases and 1064 controls with SLE data, and a subset of 240 cases and 272 controls with CT data. Polygenic risk scores (PRS) were constructed using results from a mega-analysis on MDD by the Psychiatric Genomics Consortium. PRS and environmental factors were tested for association with case/control status and for interaction between them. PRS significantly predicted depression, explaining 1.1% of variance in phenotype (p = 1.9 × 10−6). SLEs and CT were also associated with MDD status (p = 2.19 × 10−4 and p = 5.12 × 10−20, respectively). No interactions were found between PRS and SLEs. Significant PRSxCT interactions were found (p = 0.002), but showed an inverse association with MDD status, as cases who experienced more severe CT tended to have a lower PRS than other cases or controls. This relationship between PRS and CT was not observed in independent replication samples. CT is a strong risk factor for MDD but may have greater effect in individuals with lower genetic liability for the disorder. Including environmental risk along with genetics is important in studying the aetiology of MDD and PRS provide a useful approach to investigating gene–environment interactions in complex traits.

Validation of Electronic Health Record Phenotyping of Bipolar Disorder Cases and Controls

Objective: The study was designed to validate use of elec-tronic health records (EHRs) for diagnosing bipolar disorder and classifying control subjects. Method: EHR data were obtained from a health care system of more than 4.6 million patients spanning more than 20 years. Experienced clinicians reviewed charts to identify text features and coded data consistent or inconsistent with a diagnosis of bipolar disorder. Natural language processing was used to train a diagnostic algorithm with 95% specificity for classifying bipolar disorder. Filtered coded data were used to derive three additional classification rules for case subjects and one for control subjects. The positive predictive value (PPV) of EHR-based bipolar disorder and subphenotype di- agnoses was calculated against diagnoses from direct semi- structured interviews of 190 patients by trained clinicians blind to EHR diagnosis. Results: The PPV of bipolar disorder defined by natural language processing was 0.85. Coded classification based on strict filtering achieved a value of 0.79, but classifications based on less stringent criteria performed less well. No EHR- classified control subject received a diagnosis of bipolar dis- order on the basis of direct interview (PPV=1.0). For most subphenotypes, values exceeded 0.80. The EHR-based clas- sifications were used to accrue 4,500 bipolar disorder cases and 5,000 controls for genetic analyses. Conclusions: Semiautomated mining of EHRs can be used to ascertain bipolar disorder patients and control subjects with high specificity and predictive value compared with diagnostic interviews. EHRs provide a powerful resource for high-throughput phenotyping for genetic and clinical research.

Seasonality Shows Evidence for Polygenic Architecture and Genetic Correlation With Schizophrenia and Bipolar Disorder

OBJECTIVE: To test common genetic variants for association with seasonality (seasonal changes in mood and behavior) and to investigate whether there are shared genetic risk factors between psychiatric disorders and seasonality. METHOD: Genome-wide association studies (GWASs) were conducted in Australian (between 1988 and 1990 and between 2010 and 2013) and Amish (between May 2010 and December 2011) samples in whom the Seasonal Pattern Assessment Questionnaire (SPAQ) had been administered, and the results were meta-analyzed in a total sample of 4,156 individuals. Genetic risk scores based on results from prior large GWAS studies of bipolar disorder, major depressive disorder (MDD), and schizophrenia were calculated to test for overlap in risk between psychiatric disorders and seasonality. RESULTS: The most significant association was with rs11825064 (P = 1.7 × 10⁻⁶, β = 0.64, standard error = 0.13), an intergenic single nucleotide polymorphism (SNP) found on chromosome 11. The evidence for overlap in risk factors was strongest for schizophrenia and seasonality, with the schizophrenia genetic profile scores explaining 3% of the variance in log-transformed global seasonality scores. Bipolar disorder genetic profile scores were also associated with seasonality, although at much weaker levels (minimum P value = 3.4 × 10⁻³), and no evidence for overlap in risk was detected between MDD and seasonality. CONCLUSIONS: Common SNPs of large effect most likely do not exist for seasonality in the populations examined. As expected, there were overlapping genetic risk factors for bipolar disorder (but not MDD) with seasonality. Unexpectedly, the risk for schizophrenia and seasonality had the largest overlap, an unprecedented finding that requires replication in other populations and has potential clinical implications considering overlapping cognitive deficits in seasonal affective disorders and schizophrenia.

Improving the Psychometric Utility of the Hypomania Checklist (HCL-32): a Rasch Analysis Approach

Background The HCL-32 is a widely-used screening questionnaire for hypomania. We aimed to use a Rasch analysis approach to (i) evaluate the measurement properties, principally unidimensionality, of the HCL-32, and (ii) generate a score table to allow researchers to convert raw HCL-32 scores into an interval-level measurement which will be more appropriate for statistical analyses. Methods Subjects were part of the Bipolar Disorder Research Network (BDRN) study with DSM-IV bipolar disorder (n=389). Multidimensionality was assessed using the Rasch fit statistics and principle components analysis of the residuals (PCA). Item invariance (differential item functioning, DIF) was tested for gender, bipolar diagnosis and current mental state. Item estimates and reliabilities were calculated. Results Three items (29, 30, 32) had unacceptable fit to the Rasch unidimensional model. Item 14 displayed significant DIF for gender and items 8 and 17 for current mental state. Item estimates confirmed that not all items measure hypomania equally. Limitations This sample was recruited as part of a large ongoing genetic epidemiology study of bipolar disorder and may not be fully representative of the broader clinical population of individuals with bipolar disorder. Conclusion The HCL-32 is unidimensional in practice, but measurements may be further strengthened by the removal of four items. Re-scored linear measurements may be more appropriate for clinical research.

Identifying health inequalities in individuals with major mental illness (MMI) using routine data

Abstract and Summary of Thesis: Background: Individuals with Major Mental Illness (such as schizophrenia and bipolar disorder) experience increased rates of physical health comorbidity compared to the general population. They also experience inequalities in access to certain aspects of healthcare. This ultimately leads to premature mortality. Studies detailing patterns of physical health comorbidity are limited by their definitions of comorbidity, single disease approach to comorbidity and by the study of heterogeneous groups. To date the investigation of possible sources of healthcare inequalities experienced by individuals with Major Mental Illness (MMI) is relatively limited. Moreover studies detailing the extent of premature mortality experienced by individuals with MMI vary both in terms of the measure of premature mortality reported and age of the cohort investigated, limiting their generalisability to the wider population. Therefore local and national data can be used to describe patterns of physical health comorbidity, investigate possible reasons for health inequalities and describe mortality rates. These findings will extend existing work in this area. Aims and Objectives: To review the relevant literature regarding: patterns of physical health comorbidity, evidence for inequalities in physical healthcare and evidence for premature mortality for individuals with MMI. To examine the rates of physical health comorbidity in a large primary care database and to assess for evidence for inequalities in access to healthcare using both routine primary care prescribing data and incentivised national Quality and Outcome Framework (QOF) data. Finally to examine the rates of premature mortality in a local context with a particular focus on cause of death across the lifespan and effect of International Classification of Disease Version 10 (ICD 10) diagnosis and socioeconomic status on rates and cause of death. Methods: A narrative review of the literature surrounding patterns of physical health comorbidity, the evidence for inequalities in physical healthcare and premature mortality in MMI was undertaken. Rates of physical health comorbidity and multimorbidity in schizophrenia and bipolar disorder were examined using a large primary care dataset (Scottish Programme for Improving Clinical Effectiveness in Primary Care (SPICE)). Possible inequalities in access to healthcare were investigated by comparing patterns of prescribing in individuals with MMI and comorbid physical health conditions with prescribing rates in individuals with physical health conditions without MMI using SPICE data. Potential inequalities in access to health promotion advice (in the form of smoking cessation) and prescribing of Nicotine Replacement Therapy (NRT) were also investigated using SPICE data. Possible inequalities in access to incentivised primary healthcare were investigated using National Quality and Outcome Framework (QOF) data. Finally a pre-existing case register (Glasgow Psychosis Clinical Information System (PsyCIS)) was linked to Scottish Mortality data (available from the Scottish Government Website) to investigate rates and primary cause of death in individuals with MMI. Rate and primary cause of death were compared to the local population and impact of age, socioeconomic status and ICD 10 diagnosis (schizophrenia vs. bipolar disorder) were investigated. Results: Analysis of the SPICE data found that sixteen out of the thirty two common physical comorbidities assessed, occurred significantly more frequently in individuals with schizophrenia. In individuals with bipolar disorder fourteen occurred more frequently. The most prevalent chronic physical health conditions in individuals with schizophrenia and bipolar disorder were: viral hepatitis (Odds Ratios (OR) 3.99 95% Confidence Interval (CI) 2.82-5.64 and OR 5.90 95% CI 3.16-11.03 respectively), constipation (OR 3.24 95% CI 3.01-3.49 and OR 2.84 95% CI 2.47-3.26 respectively) and Parkinson’s disease (OR 3.07 95% CI 2.43-3.89 and OR 2.52 95% CI 1.60-3.97 respectively). Both groups had significantly increased rates of multimorbidity compared to controls: in the schizophrenia group OR for two comorbidities was 1.37 95% CI 1.29-1.45 and in the bipolar disorder group OR was 1.34 95% CI 1.20-1.49. In the studies investigating inequalities in access to healthcare there was evidence of: under-recording of cardiovascular-related conditions for example in individuals with schizophrenia: OR for Atrial Fibrillation (AF) was 0.62 95% CI 0.52 - 0.73, for hypertension 0.71 95% CI 0.67 - 0.76, for Coronary Heart Disease (CHD) 0.76 95% CI 0.69 - 0.83 and for peripheral vascular disease (PVD) 0.83 95% CI 0.72 - 0.97. Similarly in individuals with bipolar disorder OR for AF was 0.56 95% CI 0.41-0.78, for hypertension 0.69 95% CI 0.62 - 0.77 and for CHD 0.77 95% CI 0.66 - 0.91. There was also evidence of less intensive prescribing for individuals with schizophrenia and bipolar disorder who had comorbid hypertension and CHD compared to individuals with hypertension and CHD who did not have schizophrenia or bipolar disorder. Rate of prescribing of statins for individuals with schizophrenia and CHD occurred significantly less frequently than in individuals with CHD without MMI (OR 0.67 95% CI 0.56-0.80). Rates of prescribing of 2 or more anti-hypertensives were lower in individuals with CHD and schizophrenia and CHD and bipolar disorder compared to individuals with CHD without MMI (OR 0.66 95% CI 0.56-0.78 and OR 0.55 95% CI 0.46-0.67, respectively). Smoking was more common in individuals with MMI compared to individuals without MMI (OR 2.53 95% CI 2.44-2.63) and was particularly increased in men (OR 2.83 95% CI 2.68-2.98). Rates of ex-smoking and non-smoking were lower in individuals with MMI (OR 0.79 95% CI 0.75-0.83 and OR 0.50 95% CI 0.48-0.52 respectively). However recorded rates of smoking cessation advice in smokers with MMI were significantly lower than the recorded rates of smoking cessation advice in smokers with diabetes (88.7% vs. 98.0%, p<0.001), smokers with CHD (88.9% vs. 98.7%, p<0.001) and smokers with hypertension (88.3% vs. 98.5%, p<0.001) without MMI. The odds ratio of NRT prescription was also significantly lower in smokers with MMI without diabetes compared to smokers with diabetes without MMI (OR 0.75 95% CI 0.69-0.81). Similar findings were found for smokers with MMI without CHD compared to smokers with CHD without MMI (OR 0.34 95% CI 0.31-0.38) and smokers with MMI without hypertension compared to smokers with hypertension without MMI (OR 0.71 95% CI 0.66-0.76). At a national level, payment and population achievement rates for the recording of body mass index (BMI) in MMI was significantly lower than the payment and population achievement rates for BMI recording in diabetes throughout the whole of the UK combined: payment rate 92.7% (Inter Quartile Range (IQR) 89.3-95.8 vs. 95.5% IQR 93.3-97.2, p<0.001 and population achievement rate 84.0% IQR 76.3-90.0 vs. 92.5% IQR 89.7-94.9, p<0.001 and for each country individually: for example in Scotland payment rate was 94.0% IQR 91.4-97.2 vs. 96.3% IQR 94.3-97.8, p<0.001. Exception rate was significantly higher for the recording of BMI in MMI than the exception rate for BMI recording in diabetes for the UK combined: 7.4% IQR 3.3-15.9 vs. 2.3% IQR 0.9-4.7, p<0.001 and for each country individually. For example in Scotland exception rate in MMI was 11.8% IQR 5.4-19.3 compared to 3.5% IQR 1.9-6.1 in diabetes. Similar findings were found for Blood Pressure (BP) recording: across the whole of the UK payment and population achievement rates for BP recording in MMI were also significantly reduced compared to payment and population achievement rates for the recording of BP in chronic kidney disease (CKD): payment rate: 94.1% IQR 90.9-97.1 vs.97.8% IQR 96.3-98.9 and p<0.001 and population achievement rate 87.0% IQR 81.3-91.7 vs. 97.1% IQR 95.5-98.4, p<0.001. Exception rates again were significantly higher for the recording of BP in MMI compared to CKD (6.4% IQR 3.0-13.1 vs. 0.3% IQR 0.0-1.0, p<0.001). There was also evidence of differences in rates of recording of BMI and BP in MMI across the UK. BMI and BP recording in MMI were significantly lower in Scotland compared to England (BMI:-1.5% 99% CI -2.7 to -0.3%, p<0.001 and BP: -1.8% 99% CI -2.7 to -0.9%, p<0.001). While rates of BMI and BP recording in diabetes and CKD were similar in Scotland compared to England (BMI: -0.5 99% CI -1.0 to 0.05, p=0.004 and BP: 0.02 99% CI -0.2 to 0.3, p=0.797). Data from the PsyCIS cohort showed an increase in Standardised Mortality Ratios (SMR) across the lifespan for individuals with MMI compared to the local Glasgow and wider Scottish populations (Glasgow SMR 1.8 95% CI 1.6-2.0 and Scotland SMR 2.7 95% CI 2.4-3.1). Increasing socioeconomic deprivation was associated with an increased overall rate of death in MMI (350.3 deaths/10,000 population/5 years in the least deprived quintile compared to 794.6 deaths/10,000 population/5 years in the most deprived quintile). No significant difference in rate of death for individuals with schizophrenia compared with bipolar disorder was reported (6.3% vs. 4.9%, p=0.086), but primary cause of death varied: with higher rates of suicide in individuals with bipolar disorder (22.4% vs. 11.7%, p=0.04). Discussion: Local and national datasets can be used for epidemiological study to inform local practice and complement existing national and international studies. While the strengths of this thesis include the large data sets used and therefore their likely representativeness to the wider population, some limitations largely associated with using secondary data sources are acknowledged. While this thesis has confirmed evidence of increased physical health comorbidity and multimorbidity in individuals with MMI, it is likely that these findings represent a significant under reporting and likely under recognition of physical health comorbidity in this population. This is likely due to a combination of patient, health professional and healthcare system factors and requires further investigation. Moreover, evidence of inequality in access to healthcare in terms of: physical health promotion (namely smoking cessation advice), recording of physical health indices (BMI and BP), prescribing of medications for the treatment of physical illness and prescribing of NRT has been found at a national level. While significant premature mortality in individuals with MMI within a Scottish setting has been confirmed, more work is required to further detail and investigate the impact of socioeconomic deprivation on cause and rate of death in this population. It is clear that further education and training is required for all healthcare staff to improve the recognition, diagnosis and treatment of physical health problems in this population with the aim of addressing the significant premature mortality that is seen. Conclusions: Future work lies in the challenge of designing strategies to reduce health inequalities and narrow the gap in premature mortality reported in individuals with MMI. Models of care that allow a much more integrated approach to diagnosing, monitoring and treating both the physical and mental health of individuals with MMI, particularly in areas of social and economic deprivation may be helpful. Strategies to engage this “hard to reach” population also need to be developed. While greater integration of psychiatric services with primary care and with specialist medical services is clearly vital the evidence on how best to achieve this is limited. While the National Health Service (NHS) is currently undergoing major reform, attention needs to be paid to designing better ways to improve the current disconnect between primary and secondary care. This should then help to improve physical, psychological and social outcomes for individuals with MMI.

Post-Traumatic Stress Disorder (PTSD) and Its relationship with perinatal bereavement: definitions, reactions, adjustments, and grief.

A small percentage of women present with diagnosed PTSD post childbirth; however, though this an area of increasing research and clinical interest generally, little is known about PTSD in relation to perinatal bereavement. Health professionals must however be aware of the mechanisms and models of loss following perinatal bereavement in order to identify potential mental health phenomena which may be implicated in the development of PTSD symptomology. Understanding the predictive factors which may give early warning signs is an important component of the clinical evidence base. This chapter discusses mechanisms, models, and risk factors in relation to perinatal bereavement and the development of PTSD.

The pathophysiology of CADASIL: studies in a Scottish cohort

Since identification that mutations in NOTCH3 are responsible for cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASIL) in the early 1990s, there has been extensive characterisation of the clinical and radiological features of the disease. However therapeutic interventions remain elusive, partly due to a limited understanding of the vascular pathophysiology and how it leads to the development of strokes, cognitive decline and disability. The apparent rarity and heterogenous natural history of CADASIL potentially make conducting any longitudinal or therapeutic trials difficult. The role of disease biomarkers is therefore of some interest. This thesis focuses on vascular function in CADASIL and how it may relate to clinical and radiological markers of disease. Establishing the prevalence of CADASIL in the West of Scotland was important to assess the impact of the disease, and how feasible a trial would be. A mutation prevalence of 10.7 per 100,000 was demonstrated, suggesting significant under diagnosis of the disease across much of Scotland. Cerebral hypoperfusion is thought to be important in CADASIL, and it has been shown that vascular abnormalities precede the development of brain pathology in mouse models. Investigation of vascular function in patients, both in the brain and systemically, requires less invasive measures. Arterial spin labelling magnetic resonance imaging (MRI) and transcranial Doppler ultrasound (TCD) can both be used to obtain non-invasive and quantifiable indices of vascular function. Monitoring patients with MRI whilst they receive different concentrations of inspired oxygen and carbon dioxide can provide information on brain function, and I reviewed the practicalities of this technique in order to guide the design of the studies in this thesis. 22 CADASIL patients were recruited to a longitudinal study. Testing included peripheral vascular assessment, assessment of disability, neurological dysfunction, mood and cognition. A CO2 reactivity challenge during both TCD and arterial spin labelling MRI, and detailed MRI sequences were obtained. I was able to demonstrate that vasoreactivity was associated with the number of lacunes and brain atrophy, as were carotid intima-media thickness, vessel stiffness, and age. Patients with greater disability, higher depressive symptoms and poorer processing speed showed a tendency to worse cerebral vasoreactivity but numbers were small. This observation suggests vasoreactivity may have potential as a therapeutic target, or a biomarker. I then wished to establish if arterial spin labelling MRI was useful for assessing change in cerebral blood flow in CADASIL patients. Cortical grey matter showed the highest blood flow, mean (SD), 55 (10) ml/100g/min and blood flow was significantly lower within hyperintensities (19 (4) ml/100g/min; p <0.001). Over one year, blood flow in both grey matter (mean -7 (10) %; p = 0.028) and deep white matter (-8 (13) %; p = 0.036) declined significantly. Cerebrovascular reactivity did not change over one year. I then investigated whether baseline vascular markers were able to predict change in radiological or neuropsychological measures of disease. Changes in brain volume, lacunes, microbleeds and normalised subcortical hyperintensity volume (increase of 0.8%) were shown over one year. Baseline vascular parameters were not able to predict these changes, or those in neuropsychological testing. NOTCH3 is found throughout the body and a systemic vasculopathy has been seen particularly affecting resistance vessels. Gluteal biopsies were obtained from 20 CADASIL patients, and ex vivo myography investigated the response to vasoactive agents. Evidence of impairment in both vasodilation and vasoconstriction was shown. The addition of antioxidants improved endothelium-dependent relaxation, indicating a role for oxidative stress in CADASIL pathology. Myography measures were not related to in vivo measures in the sub-group of patients who had taken part in both studies. The small vessels affected in CADASIL are unable to be imaged by conventional MR imaging so I aimed to establish which vessels might be responsible for lacunes with use of a microangiographic template overlaid onto brain images registered to a standard brain template. This showed most lacunes are small and associated with tertiary arterioles. On the basis of this thesis, it is concluded that vascular dysfunction plays an important role in the pathophysiology of CADASIL, and further assessment of vascular measures in longitudinal studies is needed. Arterial spin labelling MRI should be used as it is a reliable, non-invasive modality that can measure change over one year. Furthermore conventional cardiovascular risk factor prevention should be undertaken in CADASIL patients to delay the deleterious effects of the disease.

Exploring the potential role of allostatic load biomarkers in risk assessment of patients presenting with depressive symptoms

Background: Depression is a major health problem worldwide and the majority of patients presenting with depressive symptoms are managed in primary care. Current approaches for assessing depressive symptoms in primary care are not accurate in predicting future clinical outcomes, which may potentially lead to over or under treatment. The Allostatic Load (AL) theory suggests that by measuring multi-system biomarker levels as a proxy of measuring multi-system physiological dysregulation, it is possible to identify individuals at risk of having adverse health outcomes at a prodromal stage. Allostatic Index (AI) score, calculated by applying statistical formulations to different multi-system biomarkers, have been associated with depressive symptoms. Aims and Objectives: To test the hypothesis, that a combination of allostatic load (AL) biomarkers will form a predictive algorithm in defining clinically meaningful outcomes in a population of patients presenting with depressive symptoms. The key objectives were: 1. To explore the relationship between various allostatic load biomarkers and prevalence of depressive symptoms in patients, especially in patients diagnosed with three common cardiometabolic diseases (Coronary Heart Disease (CHD), Diabetes and Stroke). 2 To explore whether allostatic load biomarkers predict clinical outcomes in patients with depressive symptoms, especially in patients with three common cardiometabolic diseases (CHD, Diabetes and Stroke). 3 To develop a predictive tool to identify individuals with depressive symptoms at highest risk of adverse clinical outcomes. Methods: Datasets used: ‘DepChron’ was a dataset of 35,537 patients with existing cardiometabolic disease collected as a part of routine clinical practice. ‘Psobid’ was a research data source containing health related information from 666 participants recruited from the general population. The clinical outcomes for 3 both datasets were studied using electronic data linkage to hospital and mortality health records, undertaken by Information Services Division, Scotland. Cross-sectional associations between allostatic load biomarkers calculated at baseline, with clinical severity of depression assessed by a symptom score, were assessed using logistic and linear regression models in both datasets. Cox’s proportional hazards survival analysis models were used to assess the relationship of allostatic load biomarkers at baseline and the risk of adverse physical health outcomes at follow-up, in patients with depressive symptoms. The possibility of interaction between depressive symptoms and allostatic load biomarkers in risk prediction of adverse clinical outcomes was studied using the analysis of variance (ANOVA) test. Finally, the value of constructing a risk scoring scale using patient demographics and allostatic load biomarkers for predicting adverse outcomes in depressed patients was investigated using clinical risk prediction modelling and Area Under Curve (AUC) statistics. Key Results: Literature Review Findings. The literature review showed that twelve blood based peripheral biomarkers were statistically significant in predicting six different clinical outcomes in participants with depressive symptoms. Outcomes related to both mental health (depressive symptoms) and physical health were statistically associated with pre-treatment levels of peripheral biomarkers; however only two studies investigated outcomes related to physical health. Cross-sectional Analysis Findings: In DepChron, dysregulation of individual allostatic biomarkers (mainly cardiometabolic) were found to have a non-linear association with increased probability of co-morbid depressive symptoms (as assessed by Hospital Anxiety and Depression Score HADS-D≥8). A composite AI score constructed using five biomarkers did not lead to any improvement in the observed strength of the association. In Psobid, BMI was found to have a significant cross-sectional association with the probability of depressive symptoms (assessed by General Health Questionnaire GHQ-28≥5). BMI, triglycerides, highly sensitive C - reactive 4 protein (CRP) and High Density Lipoprotein-HDL cholesterol were found to have a significant cross-sectional relationship with the continuous measure of GHQ-28. A composite AI score constructed using 12 biomarkers did not show a significant association with depressive symptoms among Psobid participants. Longitudinal Analysis Findings: In DepChron, three clinical outcomes were studied over four years: all-cause death, all-cause hospital admissions and composite major adverse cardiovascular outcome-MACE (cardiovascular death or admission due to MI/stroke/HF). Presence of depressive symptoms and composite AI score calculated using mainly peripheral cardiometabolic biomarkers was found to have a significant association with all three clinical outcomes over the following four years in DepChron patients. There was no evidence of an interaction between AI score and presence of depressive symptoms in risk prediction of any of the three clinical outcomes. There was a statistically significant interaction noted between SBP and depressive symptoms in risk prediction of major adverse cardiovascular outcome, and also between HbA1c and depressive symptoms in risk prediction of all-cause mortality for patients with diabetes. In Psobid, depressive symptoms (assessed by GHQ-28≥5) did not have a statistically significant association with any of the four outcomes under study at seven years: all cause death, all cause hospital admission, MACE and incidence of new cancer. A composite AI score at baseline had a significant association with the risk of MACE at seven years, after adjusting for confounders. A continuous measure of IL-6 observed at baseline had a significant association with the risk of three clinical outcomes- all-cause mortality, all-cause hospital admissions and major adverse cardiovascular event. Raised total cholesterol at baseline was associated with lower risk of all-cause death at seven years while raised waist hip ratio- WHR at baseline was associated with higher risk of MACE at seven years among Psobid participants. There was no significant interaction between depressive symptoms and peripheral biomarkers (individual or combined) in risk prediction of any of the four clinical outcomes under consideration. Risk Scoring System Development: In the DepChron cohort, a scoring system was constructed based on eight baseline demographic and clinical variables to predict the risk of MACE over four years. The AUC value for the risk scoring system was modest at 56.7% (95% CI 55.6 to 57.5%). In Psobid, it was not possible to perform this analysis due to the low event rate observed for the clinical outcomes. Conclusion: Individual peripheral biomarkers were found to have a cross-sectional association with depressive symptoms both in patients with cardiometabolic disease and middle-aged participants recruited from the general population. AI score calculated with different statistical formulations was of no greater benefit in predicting concurrent depressive symptoms or clinical outcomes at follow-up, over and above its individual constituent biomarkers, in either patient cohort. SBP had a significant interaction with depressive symptoms in predicting cardiovascular events in patients with cardiometabolic disease; HbA1c had a significant interaction with depressive symptoms in predicting all-cause mortality in patients with diabetes. Peripheral biomarkers may have a role in predicting clinical outcomes in patients with depressive symptoms, especially for those with existing cardiometabolic disease, and this merits further investigation.

Feasibility of resting-state microstates neurofeedback

Despite major progress, currently available treatment options for patients suffering from schizophrenia remain suboptimal. Antipsychotic medication is one such option, and is helpful in acute phases of the disease. However, antipsychotics cause significant side-effects that often require additional medication, and can even trigger the discontinuation of treatment. Taken together, along with the fact that 20-30% of patients are medication-resistant, it is clear that new medical care options should be developed for patients with schizophrenia. Besides medication, an emerging option to treat psychiatric symptoms is through the use of neurofeedback. This technique has proven efficacy for other disorders and, more importantly, has also proven to be feasible in patients with schizophrenia. One of the major advantages of this approach is that it allows for the influence of brain states that otherwise would be inaccessible; i.e. the physiological markers underlying psychotic symptoms. EEG resting-state microstates are a very interesting electrophysiological marker of schizophrenia symptoms. Precisely, a specific class of resting-state microstates, namely microstate class D, has consistently been found to show a temporal shortening in patients with schizophrenia compared to controls, and this shortening is correlated with the presence positive psychotic symptoms. Under the scope of biological psychiatry, appropriate treatment of psychotic symptoms can be expected to modify the underlying physiological markers accompanying behavioral manifestations of a disease. We reason that if abnormal temporal parameters of resting-state microstates seem to be related to positive symptoms in schizophrenia, regulating this EEG feature might be helpful as a treatment for patients. The goal of this thesis was to prove the feasibility of microstate class D contribution self-regulation via neurofeedback. Given that no other study has attempted to regulate microstates via neurofeedback, we first tested its feasibility in a population of healthy subjects. In the first paper we describe the methodological characteristics of the neurofeedback protocol and its implementation. Neurofeedback performance was assessed by means of linear mixed effects modeling, which provided a complete profile of the neurofeedback’s training response within and between-subjects. The protocol included 20 training sessions, and each session contained three conditions: baseline (resting-state) and two active conditions: training (auditory feedback upon self-regulation performance) and transfer (self-regulation with no feedback). With linear modeling we obtained performance indices for each of them as follows: baseline carryover (baseline increments time-dependent) and learning and aptitude for each of the active conditions. Learning refers to the increase/decrease of the microstate class D contribution, time-dependent during each active condition, and aptitude refers to the constant difference of the microstate class D contribution between each active condition and baseline independent of time. The indices provided are discussed in terms of tailoring neurofeedback treatment to individual profiles so that it can be applied in future studies or clinical practice. In our sample of participants, neurofeedback proved feasible, as all participants at least showed positive results in one of the aforementioned learning indices. Furthermore, between-subjects we observed that the contribution of microstate class D across-sessions increased by 0.42% during baseline, 1.93% during training trials, and 1.83% during transfer. This range is expected to be effective in treating psychotic symptoms in patients. In the second paper presented in this thesis, we explored the possible predictors of neurofeedback success among psychological variables measured with questionnaires. An interesting finding was the negative correlation between “motivational incongruence” and some of the neurofeedback performance indices. Even though this finding requires replication, we discuss it in terms of the interfering effects of incompatible psychological processes with neurofeedback training requirements. In the third paper, we present a meta-analysis on all available studies that have related resting-state microstate abnormalities and schizophrenia. We obtained medium effect sizes for two microstate classes, namely C and D. Combining the meta-analysis results with the fact that microstate class D abnormalities are correlated with the presence of positive symptoms in patients with schizophrenia, these results add further support for the training of this precise microstate. Overall, the results obtained in this study encourage the implementation of this protocol in a population of patients with schizophrenia. However, future studies will have to show whether patients will be able to successfully self-regulate the contribution of microstate class D and, if so, whether this regulation will have an impact on symptomatology.

Perfil conductual de las drogas de diseño MBDB, MDEA y PMA en modelos animales de agresión y ansiedad

MBDB, MDEA y PMA son tres drogas de diseño, estructuralmente similares al MDMA (“éxtasis”), que se han identificado en la composición de pastillas distribuidas como “éxtasis” en entornos recreativos durante los últimos treinta años. Estas feniletilaminas sintéticas presentan un perfil psicotrópico de tipo entactógeno (con capacidad para facilitar la proximidad, el contacto y la comunicación empática), similar al del MDMA en el modelo de discriminación de drogas. El MDMA ha sido objeto de un creciente interés científico y es, hasta la fecha, la única sustancia con un perfil entactógeno de la que se han investigado sus efectos conductuales en modelos animales de agresión y ansiedad, si bien sus resultados no siempre coinciden. Aunque existen algunas evidencias de que el MDMA puede tener efectos ansiolíticos en animales de laboratorio (Lin, Burden, Christie, & Johnston, 1999; Morley & McGregor, 2000; Ho, Pawlak, Guo, & Schwarting, 2004), en otros estudios se han observado alteraciones conductuales y correlatos neuroquímicos que sugieren un efecto ansiogénico (Bhattacharya, Bhattacharya & Ghosal, 1998; Gurtman, Morley, Li, Hunt, & McGregor, 2002; Maldonado & Navarro, 2000;; Navarro & Maldonado, 2002). Asimismo, en otros trabajos se ha señalado que el MDMA induce efectos antiagresivos (reducción de las conductas de amenaza y ataque), que se acompañan de un marcado aumento de las conductas de evitación/huida y defensa/sumisión, así como de una reducción de las conductas de investigación social, sugiriendo también la existencia de un perfil ansiogénico en los encuentros agonísticos entre ratones machos (Maldonado & Navarro, 2001; Navarro & Maldonado, 1999). En contraste, hasta la fecha la información experimental de las drogas MBDB, MDEA y PMA se limita a la evaluación de sus efectos conductuales sobre la conducta motora, así como algunos estudios sobre su metabolismo y posible mecanismo de acción. El objetivo general de este trabajo de investigación ha sido estudiar el perfil conductual de MBDB, MDEA y PMA en modelos animales de agresión y ansiedad. Para ello, se han examinado los efectos del MBDB (2, 4 y 8 mg/kg), MDEA (5, 10 y 20 mg/kg) y PMA (2, 4, 8 y 12 mg/kg) utilizando el modelo de agresión inducida por aislamiento y el modelo de ansiedad del laberinto elevado en cruz en ratones machos. Los resultados indican que estas sustancias en general comparten un perfil antiagresivo inespecífico. Esta falta de especificidad se debe en unos casos al aumento de las conductas de inmovilidad (4-12 mg/kg PMA), pero también a la presencia de propiedades ansiogénicas durante la interacción social, en especial con dosis elevadas, mientras que solo las dosis más bajas parecen aumentar la proximidad social, en especial la dosis menor de MBDB. Además, estas drogas parecen alterar el patrón conductual agonístico ofensivo (MBDB y MDEA) y defensivo (MBDB, MDEA y PMA), produciendo cambios diádicos que resultan coherentes con un aumento del nivel de conflicto y de ansiedad. En consonancia, los resultados del modelo del laberinto elevado en cruz indican que el MBDB produce un aumento de la ansiedad de menor intensidad que el producido por el MDMA. Sin embargo, MDEA y PMA parecen generar un estado de hipoexploración, y solo en dosis determinadas (20 mg/kg de MDEA y 4 mg/kg de PMA) muestran alteraciones discretas que sugieren un efecto ansiogénico débil, un perfil que en conjunto podría sugerir cierta similitud con alteraciones conductuales propias de los compuestos alucinógenos. Debido a la diferencia del perfil conductual del MDEA y PMA hallados en ambos modelos, sería necesario evaluar la ansiedad y su posible relación con la dosis y/o con la presencia de un oponente en la prueba en otros modelos experimentales. Lin, H. Q., Burden, P. M., Christie, M. J., & Johnston, G. A. R. (1999). The anxiogenic-like and anxiolytic-like effects of MDMA on mice in the elevated plus-maze: A comparison with amphetamine. Pharmacology, Biochemistry and Behavior, 62(3), 403-408. Morley, K. C., & McGregor, I. S. (2000). (±)-3,4-methylenedioxymethamphetamine (MDMA, 'ecstasy') increases social interaction in rats. European Journal of Pharmacology, 408(1), 41-49. Bhattacharya, S. K., Bhattacharya, A., & Ghosal, S. (1998). Anxiogenic activity of methylenedioxymethamphetamine (Ecstasy): An experimental study. Biogenic Amines, 14(3), 217-237. Gurtman, C. G., Morley, K. C., Li, K. M., Hunt, G. E., & McGregor, I. S. (2002). Increased anxiety in rats after 3,4-methylenedioxymethamphetamine: Association with serotonin depletion. European Journal of Pharmacology, 446(1-3), 89-96. Ho, Y., Pawlak, C. R., Guo, L., & Schwarting, R. K. W. (2004). Acute and long-term consequences of single MDMA administration in relation to individual anxiety levels in the rat. Behavioural Brain Research, 149(2), 135-144. Maldonado, E., & Navarro, J. F. (2000). Effects of 3,4-methylenedioxy-methamphetamine (MDMA) on anxiety in mice tested in the light/dark box. Progress in Neuro-Psychopharmacology and Biological Psychiatry, 24(3), 463-472. Maldonado, E., & Navarro, J. F. (2001b). MDMA ('ecstasy') exhibits an anxiogenic-like activity in social encounters between male mice. Pharmacological Research, 44(1), 27-31. Navarro, J. F., & Maldonado, E. (1999). Behavioral profile of 3,4-methylenedioxy-methamphetamine (MDMA) in agonistic encounters between male mice. Progress in Neuro-Psychopharmacology and Biological Psychiatry, 23(2), 327-334. Navarro, J. F., & Maldonado, E. (2002). Acute and subchronic effects of MDMA ("ecstasy") on anxiety in male mice tested in the elevated plus-maze. Progress in Neuro-Psychopharmacology and Biological Psychiatry, 26(6), 1151-1154.

Depresión en pacientes con epilepsia: Revisión sistemática de la literatura

Esta revisión sistemática de la literatura tuvo como objetivo investigar sobre la depresión en personas con epilepsia en la última década (2005-2015), enfocándose en identificar en el paciente con epilepsia: características sociodemográficas, prevalencia de la depresión, tipos de intervención para el manejo de la depresión, factores asociados con la aparición y el mantenimiento de la depresión y por último, identificar las tendencias en investigación en el estudio de la depresión en pacientes con epilepsia. Se revisaron 103 artículos publicados entre 2005 y 2015 en bases de datos especializadas. Los resultados revelaron que la prevalencia de depresión en pacientes con epilepsia es diversa y oscila en un rango amplio entre 3 y 70 %, por otro lado, que las principales características sociodemográficas asociadas a la depresión está el ser mujer, tener un estado civil soltero y tener una edad comprendida entre los 25 y los 45 años. A esto se añade, que los tratamientos conformados por terapia psicológica y fármacos, son la mejor opción para garantizar la eficacia en los resultados del manejo de la depresión en los pacientes con epilepsia. Con respecto a los factores asociados a la aparición de la depresión en pacientes con epilepsia, se identificaron causas tanto neurobiológicas como psicosociales, asimismo los factores principales asociados al mantenimiento fueron una percepción de baja calidad de vida y una baja auto-eficacia. Y finalmente los tipos de investigación más comunes son de tipo aplicado, de carácter descriptivo, transversales y de medición cuantitativa.

Relación entre atrofia cortical difusa y desempeño cognitivo : estudio en población mayor de 60 años en un hospital universitario en la ciudad de Bogotá

El presente trabajo tuvo como objetivo evaluar la existencia de la relación entre la atrofia cortical difusa objetivada por neuroimagenes cerebrales y desempeños cognitivos determinados mediante la aplicación de pruebas neuropsicológicas que evalúan memoria de trabajo, razonamiento simbólico verbal y memoria anterógrada declarativa. Participaron 114 sujetos reclutados en el Hospital Universitario Mayor Méderi de la ciudad de Bogotá mediante muestreo de conveniencia. Los resultados arrojaron diferencias significativas entre los dos grupos (pacientes con diagnóstico de atrofia cortical difusa y pacientes con neuroimagenes interpretadas como dentro de los límites normales) en todas las pruebas neuropsicológicas aplicadas. Respecto a las variables demográficas se pudo observar que el grado de escolaridad contribuye como factor neuroprotector de un posible deterioro cognitivo. Tales hallazgos son importantes para determinar protocoles tempranos de detección de posible instalación de enfermedades neurodegenerativas primarias.