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Regular physical activity for adults is associated with optimal appetite regulation, though little work has been performed in adolescents. To address this gap in the literature, we conducted a study examining appetite across a range of physical activity and adiposity levels in adolescent males. Healthy males (N=46, 14-18 years old) were recruited across four body weight and activity categories: normal weight/high active (n=11), normal weight/low active (n=13), overweight, obese/high active (n=14), overweight, obese/low active (n=8). Participants from each group completed a six-hour appetite assessment session on Day 0, followed immediately by a 14-day free-living physical activity and dietary assessment period on Days 1-14, and a fitness test session occurring between Days 15-18. Subjective and objective assessment of appetite, resting energy expenditure, body composition using dual energy absorptiometry‘, and thermic effect of feeding was conducted on Day 0. Physiological variables in the normal weight low active group that were different than their peers included lower fat-free mass, cardiorespiratory fitness, glucose/fullness response to a standardized meal, thermic effect of feeding in response to a standardized meal, lower self-rated fullness and satiety, and higher self-rated hunger to a standardized meal. Conversely, the overweight, obese high active group displayed better subjective appetite responses, but higher insulin responses to a standardized meal. Taken together, these results suggest that physical inactivity during adolescence has a negative impact on metabolic health and appetite control which may contribute to future weight gain.
Although current prescribing guidelines suggest continuation of psychotropic drugs in pregnant women, population-based evidence supporting their safety is limited.
Aims
This study aims to clarify the plausible causal links between maternal psychotropic drug exposures and obstetric complications.
Method
This cohort study investigated all births by Hong Kong residents ≥18 years of age in public hospitals between 2004 and 2022. Birth episodes were classified according to whether they were unexposed to psychotropic drugs, exposed but discontinued before conception or exposed during pregnancy. Firth’s penalised logistic regression was employed in all analysis, and negative control analysis was conducted to assess causality. False discovery rate correction and sensitivity analyses were performed.
Results
Among 587 419 births, 7182 episodes involved psychotropic prescriptions (antipsychotics, antidepressants, anticonvulsants, benzodiazepines) during pregnancy. In broad drug class analysis, all significant associations observed in the exposed group were also observed in negative control analysis (psychotropics discontinued before conception), suggesting that elevated risks could be attributed to unmeasured confounders. Nevertheless, in subclass analyses, certain psychotropic drugs showed increased risks of obstetric complications, i.e. significant associations between atypical antipsychotics and genito-urinary infection (odds ratio 2.70, 95% CI 1.46–4.83), and between valproate and low birth weight (odds ratio 1.68, 95% CI 1.16–2.37). These associations became non-significant in negative control analysis, and the high E-values (atypical antipsychotics and genito-urinary infection, 4.84; valproate and low birth weight, 2.75) suggested that the results were unlikely to have been driven by unmeasured confounders. Maternal diagnoses of schizophrenia and depression were independently associated with increased risk of obstetric complications, after controlling for the effects of psychotropics.
Conclusions
The population-based data and meticulous analyses did not support any clear causal link between broad-class psychotropic exposure during pregnancy and increased risk of obstetric/neonatal complications. However, some psychotropic subclasses may increase obstetric/neonatal complications. The limited number of episodes involving discontinuation of some psychotropic subclasses may have resulted in false negative findings in the negative control analysis.
Genetic research on nicotine dependence has utilized multiple assessments that are in weak agreement.
Methods
We conducted a genome-wide association study (GWAS) of nicotine dependence defined using the Diagnostic and Statistical Manual of Mental Disorders (DSM-NicDep) in 61,861 individuals (47,884 of European ancestry [EUR], 10,231 of African ancestry, and 3,746 of East Asian ancestry) and compared the results to other nicotine-related phenotypes.
Results
We replicated the well-known association at the CHRNA5 locus (lead single-nucleotide polymorphism [SNP]: rs147144681, p = 1.27E−11 in EUR; lead SNP = rs2036527, p = 6.49e−13 in cross-ancestry analysis). DSM-NicDep showed strong positive genetic correlations with cannabis use disorder, opioid use disorder, problematic alcohol use, lung cancer, material deprivation, and several psychiatric disorders, and negative correlations with respiratory function and educational attainment. A polygenic score of DSM-NicDep predicted DSM-5 tobacco use disorder criterion count and all 11 individual diagnostic criteria in the independent National Epidemiologic Survey on Alcohol and Related Conditions-III sample. In genomic structural equation models, DSM-NicDep loaded more strongly on a previously identified factor of general addiction liability than a “problematic tobacco use” factor (a combination of cigarettes per day and nicotine dependence defined by the Fagerström Test for Nicotine Dependence). Finally, DSM-NicDep showed a strong genetic correlation with a GWAS of tobacco use disorder as defined in electronic health records (EHRs).
Conclusions
Our results suggest that combining the wide availability of diagnostic EHR data with nuanced criterion-level analyses of DSM tobacco use disorder may produce new insights into the genetics of this disorder.
Childhood trauma is a well-established risk factor for psychosis, paranoia, and substance use, with cannabis being a modifiable environmental factor that exacerbates these vulnerabilities. This study examines the interplay between childhood trauma, cannabis use, and paranoia using standard tetrahydrocannabinol (THC) units as a comprehensive measure of cannabis exposure.
Methods
Data were derived from the Cannabis&Me study, an observational, cross-sectional, online survey of 4,736 participants. Childhood trauma was assessed using a modified Childhood Trauma Screen Questionnaire, while paranoia was measured via the Green Paranoid Thoughts Scale. Cannabis use was quantified using weekly standard THC units. Structural equation modeling (SEM) was employed to evaluate direct and indirect pathways between trauma, cannabis use, and paranoia.
Results
Childhood trauma was strongly associated with paranoia, particularly emotional, and physical abuse (β = 16.10, q < 0.001; β = 16.40, q < 0.001). Cannabis use significantly predicted paranoia (β = 0.009, q < 0.001). Interactions emerged between standard THC units and both emotional abuse (β = 0.011, q < 0.001) and household discord (β = 0.011, q < 0.001). SEM revealed a small but significant indirect effect of trauma on paranoia via cannabis use (β = 0.004, p = 0.017).
Conclusions
These findings highlight childhood trauma as a primary driver of paranoia, with cannabis use amplifying its effects. While trauma had a strong direct impact, cannabis played a significant mediating role. Integrating standard THC units into psychiatric research and clinical assessments may enhance risk detection and refine intervention strategies, particularly for childhood trauma-exposed individuals.
Around 1000 years ago, Madagascar experienced the collapse of populations of large vertebrates that ultimately resulted in many species going extinct. The factors that led to this collapse appear to have differed regionally, but in some ways, key processes were similar across the island. This review evaluates four hypotheses that have been proposed to explain the loss of large vertebrates on Madagascar: Overkill, aridification, synergy, and subsistence shift. We explore regional differences in the paths to extinction and the significance of a prolonged extinction window across the island. The data suggest that people who arrived early and depended on hunting, fishing, and foraging had little effect on Madagascar’s large endemic vertebrates. Megafaunal decline was triggered initially by aridification in the driest bioclimatic zone, and by the arrival of farmers and herders in the wetter bioclimatic zones. Ultimately, it was the expansion of agropastoralism across both wet and dry regions that drove large endemic vertebrates to extinction everywhere.
It remains unclear which individuals with subthreshold depression benefit most from psychological intervention, and what long-term effects this has on symptom deterioration, response and remission.
Aims
To synthesise psychological intervention benefits in adults with subthreshold depression up to 2 years, and explore participant-level effect-modifiers.
Method
Randomised trials comparing psychological intervention with inactive control were identified via systematic search. Authors were contacted to obtain individual participant data (IPD), analysed using Bayesian one-stage meta-analysis. Treatment–covariate interactions were added to examine moderators. Hierarchical-additive models were used to explore treatment benefits conditional on baseline Patient Health Questionnaire 9 (PHQ-9) values.
Results
IPD of 10 671 individuals (50 studies) could be included. We found significant effects on depressive symptom severity up to 12 months (standardised mean-difference [s.m.d.] = −0.48 to −0.27). Effects could not be ascertained up to 24 months (s.m.d. = −0.18). Similar findings emerged for 50% symptom reduction (relative risk = 1.27–2.79), reliable improvement (relative risk = 1.38–3.17), deterioration (relative risk = 0.67–0.54) and close-to-symptom-free status (relative risk = 1.41–2.80). Among participant-level moderators, only initial depression and anxiety severity were highly credible (P > 0.99). Predicted treatment benefits decreased with lower symptom severity but remained minimally important even for very mild symptoms (s.m.d. = −0.33 for PHQ-9 = 5).
Conclusions
Psychological intervention reduces the symptom burden in individuals with subthreshold depression up to 1 year, and protects against symptom deterioration. Benefits up to 2 years are less certain. We find strong support for intervention in subthreshold depression, particularly with PHQ-9 scores ≥ 10. For very mild symptoms, scalable treatments could be an attractive option.
Recent changes in US government priorities have serious negative implications for science that will compromise the integrity of mental health research, which focuses on vulnerable populations. Therefore, as editors of mental science journals and custodians of the academic record, we confirm with conviction our collective commitment to communicating the truth.
Partial remission after major depressive disorder (MDD) is common and a robust predictor of relapse. However, it remains unclear to which extent preventive psychological interventions reduce depressive symptomatology and relapse risk after partial remission. We aimed to identify variables predicting relapse and to determine whether, and for whom, psychological interventions are effective in preventing relapse, reducing (residual) depressive symptoms, and increasing quality of life among individuals in partial remission. This preregistered (CRD42023463468) systematic review and individual participant data meta-analysis (IPD-MA) pooled data from 16 randomized controlled trials (n = 705 partial remitters) comparing psychological interventions to control conditions, using 1- and 2-stage IPD-MA. Among partial remitters, baseline clinician-rated depressive symptoms (p = .005) and prior episodes (p = .012) predicted relapse. Psychological interventions were associated with reduced relapse risk over 12 months (hazard ratio [HR] = 0.60, 95% confidence interval [CI] 0.43–0.84), and significantly lowered posttreatment depressive symptoms (Hedges’ g = 0.29, 95% CI 0.04–0.54), with sustained effects at 60 weeks (Hedges’ g = 0.33, 95% CI 0.06–0.59), compared to nonpsychological interventions. However, interventions did not significantly improve quality of life at 60 weeks (Hedges’ g = 0.26, 95% CI -0.06 to 0.58). No moderators of relapse prevention efficacy were found. Men, older individuals, and those with higher baseline symptom severity experienced greater reductions in symptomatology at 60 weeks. Psychological interventions for individuals with partially remitted depression reduce relapse risk and residual symptomatology, with efficacy generalizing across patient characteristics and treatment types. This suggests that psychological interventions are a recommended treatment option for this patient population.
Murayama and Jach rightfully aim to conceptualize motivation as an emergent property of a dynamic system of interacting elements. However, they do not embrace the ontological and paradigmatic constraints of the dynamic systems approach. They therefore miss the very process of emergence and how it can be formally modeled and tested by specific types of computer simulation.
To summarize insights generated during the preceding four conventions of the European Access Academy (EAA) regarding the interface of patient organizations and medical societies with the evolving European Union (EU) health technology assessment (HTA) process.
Methods
In 2022 and 2023 four EAA conventions were held on the EU HTA regulation, focusing on: (i) its relevance for beating cancer; (ii) stakeholder involvement; (iii) recommended preparatory steps to ensure its successful implementation; and (iv) the role of hematology and oncology as a pacemaker for the EU HTA process. Here we summarize insights generated at the four EAA conventions about the integration of patient and clinician insights in the evolving EU HTA process, including joint scientific consultations (JSC) and joint clinical assessments (JCA).
Results
Throughout the conventions it became clear that the interface of patient associations and clinical societies with the EU HTA process is key for successful implementation of the regulation. All involved stakeholders rely on the principles of evidence-based medicine (EBM), including best internal and external evidence, patient values and expectations, and clinical experience. It was agreed that patient and clinician perspectives on the assessments are needed to balance the technical analysis of best external evidence. While patient input is rather well defined, when and how input from clinical societies is best incorporated during the process remains unclear.
Conclusions
As stipulated by the EBM triad, systematic involvement of patients and clinicians throughout both JSC and JCA is key to ensuring best outcomes for patients and society as a whole, in line with the objectives of the EU HTA regulation.
The association between cannabis and psychosis is established, but the role of underlying genetics is unclear. We used data from the EU-GEI case-control study and UK Biobank to examine the independent and combined effect of heavy cannabis use and schizophrenia polygenic risk score (PRS) on risk for psychosis.
Methods
Genome-wide association study summary statistics from the Psychiatric Genomics Consortium and the Genomic Psychiatry Cohort were used to calculate schizophrenia and cannabis use disorder (CUD) PRS for 1098 participants from the EU-GEI study and 143600 from the UK Biobank. Both datasets had information on cannabis use.
Results
In both samples, schizophrenia PRS and cannabis use independently increased risk of psychosis. Schizophrenia PRS was not associated with patterns of cannabis use in the EU-GEI cases or controls or UK Biobank cases. It was associated with lifetime and daily cannabis use among UK Biobank participants without psychosis, but the effect was substantially reduced when CUD PRS was included in the model. In the EU-GEI sample, regular users of high-potency cannabis had the highest odds of being a case independently of schizophrenia PRS (OR daily use high-potency cannabis adjusted for PRS = 5.09, 95% CI 3.08–8.43, p = 3.21 × 10−10). We found no evidence of interaction between schizophrenia PRS and patterns of cannabis use.
Conclusions
Regular use of high-potency cannabis remains a strong predictor of psychotic disorder independently of schizophrenia PRS, which does not seem to be associated with heavy cannabis use. These are important findings at a time of increasing use and potency of cannabis worldwide.
This chapter provides a brief overview of the stochastic frontier analysis (SFA) in the context of analyzing healthcare, with a focus on hospitals, where it has received widespread attention. The authors consider many of the popular extensions and generalizations of the classic SFA model in both cross-sectional and panel data. They also briefly discuss semiparametric and nonparametric generalizations, spatial frontiers, Bayesian SFA, and the endogeneity in SFA. They illustrate some of these methods for real data on public hospitals in Queensland, Australia, as well as provide practical guidance and references for their computational implementations via R.
Positive, negative and disorganised psychotic symptom dimensions are associated with clinical and developmental variables, but differing definitions complicate interpretation. Additionally, some variables have had little investigation.
Aims
To investigate associations of psychotic symptom dimensions with clinical and developmental variables, and familial aggregation of symptom dimensions, in multiple samples employing the same definitions.
Method
We investigated associations between lifetime symptom dimensions and clinical and developmental variables in two twin and two general psychosis samples. Dimension symptom scores and most other variables were from the Operational Criteria Checklist. We used logistic regression in generalised linear mixed models for combined sample analysis (n = 875 probands). We also investigated correlations of dimensions within monozygotic (MZ) twin pairs concordant for psychosis (n = 96 pairs).
Results
Higher symptom scores on all three dimensions were associated with poor premorbid social adjustment, never marrying/cohabiting and earlier age at onset, and with a chronic course, most strongly for the negative dimension. The positive dimension was also associated with Black and minority ethnicity and lifetime cannabis use; the negative dimension with male gender; and the disorganised dimension with gradual onset, lower premorbid IQ and substantial within twin-pair correlation. In secondary analysis, disorganised symptoms in MZ twin probands were associated with lower premorbid IQ in their co-twins.
Conclusions
These results confirm associations that dimensions share in common and strengthen the evidence for distinct associations of co-occurring positive symptoms with ethnic minority status, negative symptoms with male gender and disorganised symptoms with substantial familial influences, which may overlap with influences on premorbid IQ.
This article uses a prosopographical methodology and new dataset of 1,558 CEOs from Britain’s largest public companies between 1900 and 2009 to analyze how the role, social background, and career pathways of corporate leaders changed. We have four main findings. First, the designation of CEO only prevailed in the 1990s. Second, the proportion of socially elite CEOs was highest before 1940, but they were not dominant. Third, most CEOs did not have a degree before the 1980s, or professional qualification until the 1990s. Fourth, liberal market reforms in the 1980s were associated with an increase in the likelihood of CEO dismissal by a factor of three.
OBJECTIVES/GOALS: Social isolation/loneliness is a public health crisis and one that is unlikely to be solved through pharmacology. Nonpharmacological approaches, such as dance, are needed. The objective of this study is to investigate the physiological correlates of dance-induced improvements in social connection. METHODS/STUDY POPULATION: Participants were randomly assigned to participate for 4 weeks (2 times per week, 90-minute sessions) in either 1) improvisational dance training (experimental group; n=7); or a 2) dance movie watching experience (control group; n=7). Before and after the intervention, using mobile brain-body imaging techniques, participants and their instructor had their brain (via electroencephalography) and body physiology (via photoplethysmography) recorded during a series of verbal and nonverbal interactive experiences. Participants were also video recorded via 4 surrounding cameras for later motion capture analysis. Neuropsychological assessments were also conducted before and after the intervention. RESULTS/ANTICIPATED RESULTS: We found that dance significantly increased social skills including empathy, interpersonal skills, emotional regulation, mindfulness, and attention. Additionally, we found that dance significantly increased interbrain synchrony during nonverbal experiences including theta (4-8 Hz), beta (12-35 Hz), and gamma (35-45 Hz) frequencies in the occipital lobe. Increases in interbrain synchrony were also positively correlated with increases in empathy. Additionally, intercardiac synchrony between the participant and instructor showed a significant correlation at post-intervention only. Future investigations will focus on the relationship between interbrain, intercardiac, and movement synchrony. DISCUSSION/SIGNIFICANCE: Our findings support the idea that dance increases interpersonal synchrony at the level of the brain, heart, and behavior. Understanding the neural and somatic mechanisms of social behaviors will help promote understanding and development of interventions for the critical problem of social isolation and loneliness.
This chapter gives a quick tour of classic material in univariate analytic combinatorics, including rational and meromorphic generating functions, Darboux’s method, the transfer theorems of singularity analysis, and saddle point methods for essential singularities.