Prevalence of internalizing disorders, symptoms, and traits across age using advanced nonlinear models

Connecting the dots: Network structures of internalizing and functional symptoms in a population-based cohort

OBJECTIVE

Comorbidities between internalizing disorders (IDs) and functional disorders (FDs) are well-documented, indicating shared pathways. However, their symptom-level relationships have been largely unexplored. This exploratory study employs a network approach to investigate symptoms of major depressive disorder (MDD), generalized anxiety disorder (GAD), myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), fibromyalgia (FM), and irritable bowel syndrome (IBS) to identify bridge symptoms explaining comorbidity between the two domains.

METHODS

We used cross-sectional data on 72,919 adult subjects from the Lifelines Cohort Study, a Dutch general population sample. A total of 38 symptoms representing diagnostic criteria of IDs and FDs were assessed with validated questionnaires. Network models were estimated using eLasso, based on the Ising model, to identify bridge symptoms. The Network Comparison Test (NCT) was used to test whether there were differences in network structure and strength across sex and age.

RESULTS

Symptoms were moderately connected, with a network density of 52.7%. ID and FD symptoms clustered in their respective domains, but were connected through the bridge symptoms, fatigue, difficulty concentrating, trouble sleeping, and unrefreshing sleep. Fatigue and difficulty concentrating had the most connections, associated with 86.6% and 78.9% of the other symptoms, respectively. NCTs indicated no differences in network connectivity between females versus males or younger versus older adults (>50 years).

CONCLUSIONS

ID and FD symptoms are moderately interconnected. Bridge symptoms displaying strong connections to multiple disorders may play a central role in the mechanisms underpinning the comorbidity between IDs and FDs.

Comorbidity and sex differences in functional disorders and internalizing disorders

OBJECTIVE

In the current exploratory study we estimate comorbidity rates between FDs [fibromyalgia (FM), myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), and irritable bowel syndrome (IBS)]-and IDs-[major depressive disorder (MDD) and generalized anxiety disorder (GAD)] by using self-reported diagnostic criteria.

METHOD

We analyzed data from 107,849 participants (mean age = 49.3 (SD = 13.0), 58.6% women) of the Lifelines Cohort Study. Lifelines is a prospective population-based cohort study in the northeast of the Netherlands. Current IDs were assessed using the Mini-International Neuropsychiatric Interview. Current FM, ME/CFS, and IBS were assessed according to the 2010 American College of Rheumatology criteria, the 1994 Centers for Disease Control and Prevention criteria and the ROME IV criteria, respectively. We estimated tetrachoric correlations between diagnoses and tested for sex differences. Additionally, we estimated the ratio of observed-to-expected frequency for combinations of diagnoses.

RESULTS

FDs and IDs are highly comorbid (odds ratios: 3.2-12.6) with associations stronger among men. Participants with at least three disorders/diagnoses were more prevalent than expected by chance.

CONCLUSION

Studies that aim to explain sex differences and the comorbidity of specific combinations of IDs and FDs will be an important contribution to understanding the etiology of these conditions.

Evidence for strong genetic correlations among internalizing psychopathology and related self-reported measures using both genomic and twin/adoptive approaches

The internalizing construct captures shared variance underlying risk for mood and anxiety disorders. Internalizing factors based on diagnoses (or symptoms) of major depressive disorder (MDD) and generalized anxiety disorder (GAD) are well established. Studies have also integrated self-reported measures of associated traits (e.g., questionnaires assessing neuroticism, worry, and rumination) onto these factors, despite having not tested the assumption that these measures truly capture the same sets of risk factors. This study examined the overlap among both sets of measures using converging approaches. First, using genomic structural equation modeling, we constructed internalizing factors based on genome-wide association studies (GWASs) of internalizing diagnoses (e.g., MDD) and traits associated with internalizing (neuroticism, loneliness, and reverse-scored subjective well-being). Results indicated the two factors were highly (rg = .79) but not perfectly genetically correlated (rg < 1.0, p < .001). Second, we constructed similar latent factors in a combined twin/adoption sample of adults from the Colorado Adoption/Twin Study of Lifespan Behavioral Development and Cognitive Aging. Again, both factors demonstrated strong overlap at the level of genetic (rg = .76, 95% confidence interval [CI] [0.40, 0.97]) and nonshared environmental influences (re = .80, 95% CI [0.53, 1.0]). Shared environmental influences were estimated near zero for both factors. Our findings are consistent with current frameworks of psychopathology, though they suggest there are some unique genetic influences captured by internalizing diagnosis compared to trait measures, with potentially more nonadditive genetic influences on trait measures. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Serial Mediation Models of Future Anxiety and Italian Young Adults Psychological Distress: The Role of Intolerance of Uncertainty and Non-Pathological Worry

Previous research has already examined the relationship between Future Anxiety, a construct recently introduced in Italy, and mental health in young adults, although possible mediating variables in this relationship have so far never been investigated. The present study attempts to fill this gap by exploring the incidence of Future Anxiety on psychological distress (i.e., Stress, Anxiety and Depression) in a group of 302 young Italian adults (18-30 years; M = 21.9; SD = 2.6; 49.0% males; 51.0% females), presenting and evaluating the simultaneous mediating effect of Intolerance of Uncertainty and Non-Pathological Worry. Findings highlighted how Future Anxiety had a positive and significant direct effect on Stress and Depression, but not on Anxiety. In the three serial mediation models proposed, Intolerance of Uncertainty and Non-Pathological Worry mediated the relationship between Future Anxiety and mental health outcomes. The results also confirmed the hypothesized serial mediation effect by highlighting how young adults with greater Future Anxiety experienced more Intolerance of Uncertainty, which positively affected Non-Pathological Worry levels and, in turn, exacerbated psychological distress. Finally, results indicated that female participants experienced more Stress, Anxiety, and Depression in relation to Future Anxiety compared to males. Starting from the review of main references on this subject, the results discussed provide new insights for understanding youth psychological distress. Finally, practical implications for the design of supportive interventions for this study's target group are proposed.

Validity and diagnostic overlap of functional somatic syndrome diagnoses

OBJECTIVE

We present the first study that investigates the validity and the diagnostic overlap of the three main functional somatic syndrome (FSS) diagnoses, i.e. chronic fatigue syndrome (CFS), fibromyalgia (FM), and irritable bowel syndrome (IBS), irrespective of help-seeking behaviour or diagnostic habits, and irrespective of differences in diagnostic thresholds for chronicity or symptom interference.

METHODS

This cross-sectional analysis was performed in 89,781 participants of the general-population cohort Lifelines. Diagnostic criteria for CFS (Centers for Disease Control and Prevention), FM (American College of Rheumatology) and IBS (Rome IV) were assessed by questionnaire. Additional items were added to enable studying the effects of differences in thresholds for minimum symptom chronicity (varying from three for FM to six months for CFS and IBS), and symptom interference (required for CFS but not for FM and IBS).

RESULTS

The diagnostic criteria were met by 3.1% for CFS, 6.6% for FM, and 5.5% for IBS participants. The number of participants that met criteria for all three diagnoses was 45 times higher than what would have been expected based on chance. After alignment of the chronicity and symptom interference criteria to circumvent differences in diagnostic thresholds, the overlap between diagnoses increased to 152 times. Furthermore, there was a similar pattern of symptom occurrence, particularly for those fulfilling diagnostic criteria for CFS and FM.

CONCLUSION

The diagnostic overlap of different FSS was much higher than would be expected by chance, and substantially increased when FSS were more chronic and serious in nature.

A Comparison between Farm-Related Stress, Mental Health, and Social Support between Men and Women Farmers

Agricultural producers have worse mental health than the general population; however, recent research has not considered differences in stressors and mental health conditions by gender. A survey was mailed to a random sample of farmers in Illinois to screen for symptoms of anxiety and depression and identify sources of stress and social support. Men experienced more stress related to environmental and economic conditions than women, while women tended to have slightly higher levels of geographic isolation stress than men. Overall, there were no significant differences by gender in the proportion meeting the criteria for depression or anxiety; however, the results are higher than what is observed in the general population. Among those farmers who experience higher levels of stress about geographic isolation, the odds for women farmers to experience depressive symptoms are four times more than men farmers (OR 4.46 (0.91, 21.8); p = 0.06). Additional research should examine the relationship between social support and mental health. Interventions to reduce stress by gender should be considered.

Meta-analysis of epigenetic aging in schizophrenia reveals multifaceted relationships with age, sex, illness duration, and polygenic risk

BACKGROUND

The study of biological age acceleration may help identify at-risk individuals and reduce the rising global burden of age-related diseases. Using DNA methylation (DNAm) clocks, we investigated biological aging in schizophrenia (SCZ), a mental illness that is associated with an increased prevalence of age-related disabilities and morbidities. In a whole blood DNAm sample of 1090 SCZ cases and 1206 controls across four European cohorts, we performed a meta-analysis of differential aging using three DNAm clocks (i.e., Hannum, Horvath, and Levine). To dissect how DNAm aging contributes to SCZ, we integrated information on duration of illness and SCZ polygenic risk, as well as stratified our analyses by chronological age and biological sex.

RESULTS

We found that blood-based DNAm aging is significantly altered in SCZ independent from duration of the illness since onset. We observed sex-specific and nonlinear age effects that differed between clocks and point to possible distinct age windows of altered aging in SCZ. Most notably, intrinsic cellular age (Horvath clock) is decelerated in SCZ cases in young adulthood, while phenotypic age (Levine clock) is accelerated in later adulthood compared to controls. Accelerated phenotypic aging was most pronounced in women with SCZ carrying a high polygenic burden with an age acceleration of + 3.82 years (CI 2.02-5.61, P = 1.1E-03). Phenotypic aging and SCZ polygenic risk contributed additively to the illness and together explained up to 14.38% of the variance in disease status.

CONCLUSIONS

Our study contributes to the growing body of evidence of altered DNAm aging in SCZ and points to intrinsic age deceleration in younger adulthood and phenotypic age acceleration in later adulthood in SCZ. Since increased phenotypic age is associated with increased risk of all-cause mortality, our findings indicate that specific and identifiable patient groups are at increased mortality risk as measured by the Levine clock. Our study did not find that DNAm aging could be explained by the duration of illness of patients, but we did observe age- and sex-specific effects that warrant further investigation. Finally, our results show that combining genetic and epigenetic predictors can improve predictions of disease outcomes and may help with disease management in schizophrenia.

How Is the Fear of War Impacting Italian Young Adults' Mental Health? The Mediating Role of Future Anxiety and Intolerance of Uncertainty

The Russian-Ukrainian conflict is affecting mental health even in communities that are not directly involved in the war; added to this is the escalating conflict in the Middle East and its dangerous spread, which brings the war back to the center of the contemporary social and economic horizon. The present study aims to explore the psychological impact of war in a sample of 310 Italian young adults (18-30 years; M = 22.0; SD = 2.6) while exploring the relationship between Fear of War and psychological distress and evaluating the mediating effects of Future Anxiety and Intolerance of Uncertainty in this relation. Findings highlighted how Fear of War positively and significantly affects Stress, Anxiety, and Depression, and, at the same time, how it fuels both Future Anxiety and Intolerance of Uncertainty. These constructs, in addition to positively affecting the mental health outcomes considered, mediate the relationship between Fear of War and youth psychological distress with a significant indirect effect observed in all three mediation models performed. Finally, significantly higher levels of psychological distress, Fear of War, and Future Anxiety are reported in women than in men. The findings are discussed with reference to the recent literature on the psychological impact of war and on contemporary youth psychological distress, indicating the importance of educational policies and targeted interventions aimed at supporting this target in coping with multiple contemporary collective stressors.

Genomics Research of Lifetime Depression in the Netherlands: The BIObanks Netherlands Internet Collaboration (BIONIC) Project

In this cohort profile article we describe the lifetime major depressive disorder (MDD) database that has been established as part of the BIObanks Netherlands Internet Collaboration (BIONIC). Across the Netherlands we collected data on Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) lifetime MDD diagnosis in 132,850 Dutch individuals. Currently, N = 66,684 of these also have genomewide single nucleotide polymorphism (SNP) data. We initiated this project because the complex genetic basis of MDD requires large population-wide studies with uniform in-depth phenotyping. For standardized phenotyping we developed the LIDAS (LIfetime Depression Assessment Survey), which then was used to measure MDD in 11 Dutch cohorts. Data from these cohorts were combined with diagnostic interview depression data from 5 clinical cohorts to create a dataset of N = 29,650 lifetime MDD cases (22%) meeting DSM-5 criteria and 94,300 screened controls. In addition, genomewide genotype data from the cohorts were assembled into a genomewide association study (GWAS) dataset of N = 66,684 Dutch individuals (25.3% cases). Phenotype data include DSM-5-based MDD diagnoses, sociodemographic variables, information on lifestyle and BMI, characteristics of depressive symptoms and episodes, and psychiatric diagnosis and treatment history. We describe the establishment and harmonization of the BIONIC phenotype and GWAS datasets and provide an overview of the available information and sample characteristics. Our next step is the GWAS of lifetime MDD in the Netherlands, with future plans including fine-grained genetic analyses of depression characteristics, international collaborations and multi-omics studies.

Mental health across two years of the COVID-19 pandemic: a 5-wave longitudinal study in Germany

The COVID-19 pandemic has been negatively associated with mental health. However, little is known about the temporal dynamics of mental health in the longer term of the pandemic. We aimed to investigate symptom levels and changes of depression, anxiety, posttraumatic stress, and loneliness spanning two years of the pandemic; and to examine associated risk factors. This five-wave, longitudinal online study from May 2020 to April 2022 included 636 adults (Mage = 39.5 years, SD = 16.11; 84.1% female) from the German general population who completed the international COVID-19 Mental Health Survey. Symptoms of anxiety (Generalized Anxiety Disorder-7; GAD-7), depression (Patient Health Questionnaire-9; PHQ-9), posttraumatic stress (PTSD Checklist for DSM-5; PCL-5), and loneliness ("Do you feel lonely?") were assessed using mixed-effects models. Associations with anxiety and depressive symptoms were examined with having children, student status, financial worries, contamination fear, and loneliness. PHQ-9, GAD-7, PCL-5, and loneliness scores overall decreased throughout the two-year period of the pandemic but exhibited an increase during two national lockdowns. Controlled for significant associations with female gender and younger age, increased PHQ-9 and GAD-7 scores were associated with contamination fear, financial worries, and loneliness. No associations were found with having children and student status. Symptoms of depression, anxiety, posttraumatic stress, and loneliness decreased over time but varied along with the dynamics of the pandemic. Longitudinal monitoring of mental health in vulnerable subgroups is required, especially those of younger age, females, and the financially insecure.

Pharmacological approaches to the management of panic disorder in older patients: a systematic review

INTRODUCTION

Recommendations for treating panic disorder (PD) in older patients are scarce. The authors have systematically reviewed whether several recommended medications are superior to others and their optimal doses in this age group.

METHODS

A database search of studies involving patients with PD with/without agoraphobia aged ≥ 60 years was carried out using PubMed, PsycINFO, Embase, and Clinical Trials.gov, from their inception dates to 1 March 2023. Only four (published from 2002 to 2010) of the 1292 records screened were included. A risk of bias assessment was provided. This systematic review was performed using The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA).

RESULTS

Two studies were randomized clinical trials, whereas two were open-label, including paroxetine, citalopram, escitalopram, and sertraline; three studies reported short-term evaluations, whereas one study included a 26-week follow-up. Medications provided benefits, with good tolerability. Preliminary results suggested greater benefits of paroxetine in reducing panic attacks vs. cognitive - behavioral therapy, and an earlier decrease in PAs with escitalopram vs. citalopram. Risk of bias was considerable.

CONCLUSIONS

The pharmacological management of PD in older patients has received no attention. Findings are scant, dated, and affected by methodological flaws; thus, they do not provide significant advances.

Longitudinal analyses of depression, anxiety, and suicidal ideation highlight greater prevalence in the northern Dutch population during the COVID-19 lockdowns

BACKGROUND

The pandemic of the coronavirus disease 2019 (COVID-19) has led to an increased burden on mental health.

AIMS

To investigate the development of major depressive disorder (MDD), generalized anxiety disorder (GAD), and suicidal ideation in the Netherlands during the first fifteen months of the pandemic and three nation-wide lockdowns.

METHOD

Participants of the Lifelines Cohort Study -a Dutch population-based sample-reported current symptoms of MDD and GAD, including suicidal ideation, according to DSM-IV criteria. Between March 2020 and June 2021, 36,106 participants (aged 18-96) filled out a total of 629,811 questionnaires across 23 time points. Trajectories over time were estimated using generalized additive models and analyzed in relation to age, sex, and lifetime history of MDD/GAD.

RESULTS

We found non-linear trajectories for MDD and GAD with a higher number of symptoms and prevalence rates during periods of lockdown. The point prevalence of MDD and GAD peaked during the third hard lockdown at 2.88 % (95 % CI: 2.71 %-3.06 %) and 2.92 % (95 % CI: 2.76 %-3.08 %), respectively, in March 2021. Women, younger adults, and participants with a history of MDD/GAD reported significantly more symptoms. For suicidal ideation, we found a significant linear increase over time in younger participants. For example, 20-year-old participants reported 4.14× more suicidal ideation at the end of June 2021 compared to the start of the pandemic (4.64 % (CI: 3.09 %-6.96 %) versus 1.12 % (CI: 0.76 %-1.66 %)).

LIMITATIONS

Our findings should be interpreted in relation to the societal context of the Netherlands and the public health response of the Dutch government during the pandemic, which may be different in other regions in the world.

CONCLUSIONS

Our study showed greater prevalence of MDD and GAD during COVID-19 lockdowns and a continuing increase in suicidal thoughts among young adults suggesting that the pandemic and government enacted restrictions impacted mental health in the population. Our findings provide actionable insights on mental health in the population during the pandemic, which can guide policy makers and clinical care during future lockdowns and epi/pandemics.

The structure of the symptoms of major depression: Factor analysis of a lifetime worst episode of depressive symptoms in a large general population sample

BACKGROUND

A range of depressive symptoms may occur during an episode of major depression (MD). Do these symptoms describe a single disorder liability or different symptom dimensions? This study investigates the structure and clinical relevance of an expanded set of depressive symptoms in a large general population sample.

METHODS

We studied 43,431 subjects from the Dutch Lifelines Cohort Study who participated in an online survey assessing the 9 symptom criteria of MD (DSM-IV-TR) and additional depressive symptoms during their worst lifetime episode of depressive symptoms lasting two weeks or more. Exploratory factor analyses were performed on expanded sets of 9, 14, and 24 depressive symptoms. The clinical relevance of the identified symptom dimensions was analyzed in confirmatory factor analyses including ten external validators.

RESULTS

A single dimension adequately accounted for the covariation among the 9 DSM-criteria, but multiple dimensions were needed to describe the 14 and 24 depressive symptoms. Five dimensions described the structure underlying the 24 depressive symptoms. Three cognitive affective symptom dimensions were mainly associated with risk factors for MD. Two somatic dimensions -appetite/weight problems and sleep problems-were mainly associated with BMI and age, respectively.

LIMITATIONS

Respondents of our online survey tended to be more often female, older, and more highly educated than non-respondents.

CONCLUSIONS

Different symptom dimensions described the structure of depressive symptoms during a lifetime worst episode in a general population sample. These symptom dimensions resembled those reported in a large clinical sample of Han-Chinese women with recurrent MD, suggesting robustness of the syndrome of MD.

Passive exposure to e-cigarette emissions is associated with worsened mental health

BACKGROUND

Cigarette smoking, secondhand cigarette smoke (SHS) exposure, and e-cigarette use ("vaping") are each associated with increased rates of depressive symptoms and other internalizing mental health disorders. The prevalence of vaping has increased greatly, yet the mental health correlates of secondhand exposure to e-cigarette emissions are as yet to be investigated. This study examined the potential adverse mental health outcomes associated with different tobacco exposures (direct and passive), with a particular focus on the mental health correlates of secondhand exposure to e-cigarette emissions.

METHODS

The Population Assessment of Tobacco and Health Study data collected from a sample of 16,173 Wave 4 adults were used to test the hypothesis that secondhand e-cigarette emissions exposure is associated with increased odds of internalizing mental health disorders. Individuals were categorized as exclusive cigarette smokers, exclusive e-cigarette users, cigarette and e-cigarette dual users, exclusive noncombustible tobacco users, secondhand smoke exposed non-users, secondhand e-cigarette emissions exposed non-users, and non-users with no current SHS/secondhand e-cigarette aerosol exposure. Adjusted weighted logistic regression analysis was used to investigate the association between exposure type and internalizing problems as assessed by scores on the Global Appraisal of Individual Needs-Short Screener (GAIN-SS), a widely used instrument for assessing mental health problems.

RESULTS

Cigarette smokers (AOR = 2.53, 95% CI: 2.19-2.92), e-cigarette users (AOR = 3.14, 2.41-4.09), dual users (AOR = 3.37, 2.85-4.00), noncombustible tobacco users (AOR = 1.48, 1.01-2.17), SHS exposed non-users (AOR = 1.63, 1.37-1.94), and secondhand e-cigarette emissions exposed non-users (AOR = 1.43, 1.03-1.99) were each associated with increased odds of moderate to severe internalizing mental health problems as compared to unexposed non-users. Odds of internalizing problems among SHS and secondhand e-cigarette emissions exposed non-users did not differ (p = 0.46).

CONCLUSIONS

This is the first study, to our knowledge, to identify an association between recent secondhand exposure to e-cigarette emissions and mental health problems, and the risk is comparable to that of SHS. Corroboration of this relationship needs further research to explicate directionality and mechanisms underlying this association.