11 research outputs found
Existence of Marginal Pricing Equilibria in Economies with Externalities and Non Convexities.
We consider a general equilibrium model with a production sector. The consumption sets, the preferences of the consumers and the production possibilities are represented by set-valued mappings to take into account the possibility of external effects. There are no convexity assumptions on the correspondences of production. We impose to the firms to follow the marginal cost tarification which is defined with the Clarke's normal cone. We prove the existence of general equilibria under assumptions which allows us to combine works on economies with externalities and convex production sectors, and the ones on economies with marginal cost tarification and without externalities.COSTS ; CONSUMPTION ; EXTERNALITIES
Decreased telomere length in a subgroup of young individuals with bipolar disorders: replication in the FACE-BD cohort and association with the shelterin component POT1
International audienceBipolar disorder (BD) has been associated with premature cellular aging with shortened telomere length (TL) as compared to the general population. We recently identified a subgroup of young individuals with prematurely shortened TL. The aims of the present study were to replicate this observation in a larger sample and analyze the expression levels of genes associated with age or TL in a subsample of these individuals. TL was measured on peripheral blood DNA using quantitative polymerase chain reaction in a sample of 542 individuals with BD and clustering analyses were performed. Gene expression level of 29 genes, associated with aging or with telomere maintenance, was analyzed in RNA samples from a subsample of 129 individuals. Clustering analyses identified a group of young individuals (mean age 29.64 years), with shorter TL. None of the tested clinical variables were significantly associated with this subgroup. Gene expression level analyses showed significant downregulation of MYC, POT1, and CD27 in the prematurely aged young individuals compared to the young individuals with longer TL. After adjustment only POT1 remained significantly differentially expressed between the two groups of young individuals. This study confirms the existence of a subgroup of young individuals with BD with shortened TL. The observed decrease of POT1 expression level suggests a newly described cellular mechanism in individuals with BD, that may contribute to telomere shortening
Association between childhood maltreatment and the clinical course of bipolar disorders: a survival analysis of mood recurrences
International audienceObjectives: Childhood maltreatment, also referred as childhood trauma, increases the severity of Bipolar Disorders (BD). Childhood maltreatment has been associated with more frequent mood recurrences, however mostly in retrospective studies. Since scarce, further prospective studies are required to identify whether childhood maltreatment may be associated with the time to recurrence in BD.Methods: Individuals with BD (N=2008) were assessed clinically and for childhood maltreatment at baseline, and followed-up for two years. The cumulative probability of mood recurrence over time was estimated with the Turnbull's extension of the Kaplan-Meier analysis for interval-censored data, including childhood maltreatment as a whole, and then maltreatment subtypes as predictors. Analyses were adjusted for potential confounding factors.Results: The median duration of follow-up was 22.3 month (IQR:12.0-24.8). Univariable analyses showed associations between childhood maltreatment, in particular all types of abuses (emotional, physical and sexual) or emotional neglect, and a shorter time to recurrence (all p values <0.001). When including potential confounders into the multivariable models, the time to mood recurrence was associated with multiple/severe childhood maltreatment (i.e. total score above the 75th percentile) (HR=1.32 95%CI(1.11-1.57), p=0.002), and more specifically with moderate/severe physical abuse (HR=1.44 95%CI(1.21-1.73), p<0.0001). Living alone, lifetime anxiety disorders, lifetime number of mood episodes, baseline depressive and (hypo)manic symptoms and baseline use of atypical antipsychotics were also associated with the time to recurrence.Conclusions: In addition to typical predictors of mood recurrences, an exposure to multiple/severe forms of childhood maltreatment, and more specifically to moderate to severe physical abuse, may increase the risk for a mood recurrence in BD. This leads to the recommendations of more scrutiny and denser follow-up of the individuals having been exposed to such early life stressors
Comparative analysis of anticholinergic burden scales to explain iatrogenic cognitive impairment and self-reported side effects in the euthymic phase of bipolar disorders: Results from the FACE-BD cohort
Bipolar disorders (BD) are characterized by cognitive impairment during the euthymic phase, to which treatments can contribute. The anticholinergic properties of medications, i.e., the ability of a treatment to inhibit cholinergic receptors, are associated with cognitive impairment in elderly patients and people with schizophrenia but this association has not been well characterized in individuals with remitted BD. Moreover, the validity of only one anticholinergic burden scale designed to assess the anticholinergic load of medications has been tested in BD. In a literature review, we identified 31 existing scales. We first measured the associations between 27 out of the 31 scales and objective cognitive impairment in bivariable regressions. We then adjusted the bivariable models with covariates: the scales significantly associated with cognitive impairment in bivariable and multiple logistic regressions were defined as having good concurrent validity to assess cognitive impairment. In a sample of 2,031 individuals with euthymic BD evaluated with a neuropsychological battery, two scales had good concurrent validity to assess cognitive impairment, whereas chlorpromazine equivalents, lorazepam equivalents, the number of antipsychotics, or the number of treatments had not. Finally, similar analyses with subjective anticholinergic side-effects as outcome variables reported 14 scales with good concurrent validity to assess self-reported peripheral anticholinergic side-effects and 13 to assess self-reported central anticholinergic side-effects. Thus, we identified valid scales to monitor the anticholinergic burden in BD, which may be useful in estimating iatrogenic cognitive impairment in studies investigating cognition in BD
Handedness in bipolar disorders is associated with specific neurodevelopmental features: results of the BD-FACE cohort
International audienceObjectives: High rates of non-right-handedness (NRH) and mixed-handedness exist in neurodevelopmental disorders. Dysfunctional neurodevelopmental pathways may be implicated in the underlying pathophysiology of bipolar disorders (BD), at least in some subgroups. Yet little is known about correlates of NRH and mixed-handedness in BD. The objectives of this national study are to determine (i) the prevalence of NRH and mixed-handedness in a well-stabilized sample of BD individuals; (ii) if NRH/mixed-handedness in BD is associated with a different clinical, biological and neurocognitive profile.Methods: We included 2174 stabilized individuals. Participants were tested with a comprehensive battery of neuropsychological tests. Handedness was assessed using a single oral question. Learning and/or language disorders and obstetrical complications were recorded using childhood records. Common environmental, clinical and biological parameters were assessed.Results: The prevalence of NRH and mixed-handedness were, respectively, 11.6 and 2.4%. Learning/language disorders were found in 9.7% out of the total sample and were associated with atypical handedness (only dyslexia for mixed-handedness (p < 0.01), and dyslexia and dysphasia for NRH (p = 0.01 and p = 0.04, respectively). In multivariate analyses, NRH was associated with a younger age of BD onset (aOR 0.98 (95% CI 0.96-0.99) and lifetime substance use disorder (aOR 1.40 (95% CI 1.03-1.82) but not with any of the cognitive subtasks. Mixed-handedness was associated in univariate analyses with lifetime substance use disorder, lifetime cannabis use disorder (all p < 0.01) and less mood stabilizer prescription (p = 0.028). No association was found between NRH or mixed-handedness and the following parameters: trauma history, obstetrical complications, prior psychotic symptoms, bipolar subtype, attention deficit/hyperactivity disorder, peripheral inflammation or body mass index.Conclusions: Handedness may be associated with specific features in BD, possibly reflecting a specific subgroup with a neurodevelopmental load
Diet quality and associations with lactate and metabolic syndrome in bipolar disorder
International audienceBackground: Nutrition is largely affected in bipolar disorder (BD), however, there is a lack of understanding on the relationship between dietary categories, BD, and the prevalence of metabolic syndrome. The objective of this study is to examine dietary trends in BD and it is hypothesized that diets with increased consumption of seafood and high-fiber carbohydrates will be correlated to improved patient outcomes, and a lower frequency of metabolic syndrome.Methods: This retrospective cohort study includes two French cohorts. The primary cohort, FACE-BD, includes 268 stable BD patients. The second cohort, I-GIVE, includes healthy controls, both stable and acute BD and schizophrenia patients. Four dietary categories were assessed: meat, seafood, low-fiber and high-fiber carbohydrates. Dietary data from two food frequency questionnaires were normalized using min-max scaling and assessed using various statistical analyses.Results: In our primary cohort, the increased high-fiber carbohydrate consumption was correlated to lower prevalence of metabolic syndrome and improved mood. Low-fiber carbohydrate consumption is associated with higher BMI, while higher seafood consumption was correlated to improved mood and delayed age of onset. Results were not replicated in our secondary cohort.Limitations: Our populations were small and two different dietary questionnaires were used; thus, results were used to examine similarities in trends.Conclusions: Overall, various dietary trends were associated with metabolic syndrome, BMI, lactate, mood and age of onset. Improving our understanding of nutrition in BD can provide mechanistic insight, clinically relevant nutritional guidelines for precision medicine and ultimately improve the quality of lives for those with BD
Mitochondrial Biomarkers and Metabolic Syndrome in Bipolar Disorder
International audienceThe object of this study is test whether mitochondrial blood-based biomarkers are associated with markers of metabolic syndrome in bipolar disorder, hypothesizing higher lactate but unchanged cell-free circulating mitochondrial DNA levels in bipolar disorder patients with metabolic syndrome. In a cohort study, primary testing from the FondaMental Advanced Centers of Expertise for bipolar disorder (FACE-BD) was conducted, including 837 stable bipolar disorder patients. The I-GIVE validation cohort consists of 237 participants: stable and acute bipolar patients, non-psychiatric controls, and acute schizophrenia patients. Multivariable regression analyses show significant lactate association with triglycerides, fasting glucose and systolic and diastolic blood pressure. Significantly higher levels of lactate were associated with presence of metabolic syndrome after adjusting for potential confounding factors. Mitochondrial-targeted metabolomics identified distinct metabolite profiles in patients with lactate presence and metabolic syndrome, differing from those without lactate changes but with metabolic syndrome. Circulating cell-free mitochondrial DNA was not associated with metabolic syndrome. This thorough analysis mitochondrial biomarkers indicate the associations with lactate and metabolic syndrome, while showing the mitochondrial metabolites can further stratify metabolic profiles in patients with BD. This study is relevant to improve the identification and stratification of bipolar patients with metabolic syndrome and provide potential personalized-therapeutic opportunities
Clinical predictors of recurrences in bipolar disorders type 1 and 2: A FACE-BD longitudinal study
Objective: To examine which characteristics predict the time to a first mood recurrence at three years in Bipolar Disorder type I (BD-I) and type II (BD-II). Methods: Individuals with BD were followed up to 3 years. Turbull's extension of the Kaplan-Meier analysis for interval-censored data was used to estimate the cumulative probability of recurrence over time. Separate models were performed according to BD subtype to determine which baseline factors were predictive of recurrences and were adjusted for age, gender and educational level. Results: We included 630 individuals with BD-I and 505 with BD-II. The first recurrence of any polarity occurred earlier in BD-II (p = 0.03). The first depressive recurrence occurred earlier in BD-II (p < 0.0001), whereas the first (hypo)manic recurrence occurred earlier in BD-I (p = 0.0003). In BD-I, the clinical variables that were associated to the time to a first mood recurrence were depressive symptoms, lifetime rapid cycling, global activation and the number of psychotropic medications at baseline. In BD-II, the time to a first recurrence was associated with a younger age at onset of BD and a higher number of lifetime mood episodes. The Areas Under the Curve for both models were moderate. Conclusion: Predictors of recurrences showed few specificities to BD-I or BD-II. The ability to predict recurrences in BD based on socio-demographic and clinical variables remained too moderate for a transfer in daily practice. This study highlights the need for further studies that would include other types of predictors, such as molecular, cognitive or neuro-imaging ones, to achieve an accurate level of prediction of recurrences in BD.Sorbonne Universités à Paris pour l'Enseignement et la RechercheFondaMental-Cohorte