Down under
Income inequality among American states and the incidence of major depression
Roman Pabayo, Ichiro Kawachi & Stephen Gilman
Journal of Epidemiology & Community Health, forthcoming
Background: Although cross-sectional and ecological studies have shown that higher area-level income inequality is related to increased risk for depression, few longitudinal studies have been conducted. This investigation examines the relationship between state-level income inequality and major depression among adults participating in a population-based, representative longitudinal study.
Methods: We used data from the National Epidemiologic Survey on Alcohol and Related Conditions (n=34 653). Respondents completed structured diagnostic interviews at baseline (2001–2002) and follow-up (2004–2005). Weighted multilevel modelling was used to determine if US state-level income inequality (measured by the Gini coefficient) was a significant predictor of depression at baseline and at follow-up, while controlling for individual-level and state-level covariates. We also repeated the longitudinal analyses, excluding those who had a history of depression or at baseline, in order to test whether income inequality was related to incident depression.
Results: State-level inequality was associated with increased incidence of depression among women but not men. In comparison to women residing in states belonging to the lowest quintile of income inequality, women were at increased risk for depression in the second (OR=1.18, 95% CI 0.86 to 1.62), third (OR=1.22, 95% CI 0.91 to 1.62), fourth (OR=1.37, 95% CI 1.03 to 1.82) and fifth (OR=1.50, 95% CI 1.14 to 1.96) quintiles at follow-up (p<0.05 for the linear trend).
Conclusions: Living in a state with higher income inequality increases the risk for the development of depression among women.
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Recession Depression: Mental Health Effects of the 2008 Stock Market Crash
Melissa McInerney, Jennifer Mellor & Lauren Hersch Nicholas
Journal of Health Economics, December 2013, Pages 1090–1104
Abstract:
Do sudden, large wealth losses affect mental health? We use exogenous variation in the interview dates of the 2008 Health and Retirement Study to assess the impact of large wealth losses on mental health among older U.S. adults. We compare cross-wave changes in wealth and mental health for respondents interviewed before and after the October 2008 stock market crash. We find that the crash reduced wealth and increased feelings of depression and use of antidepressant drugs, and that these effects were largest among respondents with high levels of stock holdings prior to the crash. These results suggest that sudden wealth losses cause immediate declines in subjective measures of mental health. However, we find no evidence that wealth losses lead to increases in clinically-validated measures of depressive symptoms or indicators of depression.
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Financial distress and use of mental health care: Evidence from antidepressant prescription claims
Haizhen Lin et al.
Economics Letters, forthcoming
Abstract:
Using nationwide county-level longitudinal data, we show that recent declines in housing prices are associated with an increased utilization of antidepressant prescriptions among the near elderly. Our results persist in difference-in-difference models using either all non-antidepressant drugs or statins as controls.
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The Effect of Depression on Labor Market Outcomes
Lizhong Peng, Chad Meyerhoefer & Samuel Zuvekas
NBER Working Paper, September 2013
Abstract:
We estimated the effect of depression on labor market outcomes using data from the 2004-2009 Medical Expenditure Panel Survey. After accounting for the endogeneity of depression through a correlated random effects panel data specification, we found that depression reduces the likelihood of employment. We did not, however, find evidence of a causal relationship between depression and hourly wages or weekly hours worked. Our estimates are substantially smaller than those from previous studies, and imply that depression reduces the probability of employment by 2.6 percentage points. In addition, we examined the effect of depression on work impairment and found that depression increases annual work loss days by about 1.4 days (33 percent), which implies that the annual aggregate productivity loses due to depression-induced absenteeism range from $700 million to 1.4 billion in 2009 USD.
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Katherine Keyes et al.
American Journal of Epidemiology, forthcoming
Abstract:
An estimated 80% of sexually active young women in the United States use hormonal contraceptives during their reproductive years. Associations between hormonal contraceptive use and mood disturbances remain understudied, despite the hypothesis that estrogen and progesterone play a role in mood problems. In this study, we used data from 6,654 sexually active nonpregnant women across 4 waves of the National Longitudinal Study of Adolescent Health (1994–2008), focusing on women aged 25–34 years. Women were asked about hormonal contraceptive use in the context of a current sexual partnership; thus, contraceptive users were compared with other sexually active women who were using either nonhormonal contraception or no contraception. Depressive symptoms were assessed with the Center for Epidemiologic Studies Depression Scale. At ages 25–34 years, hormonal contraceptive users had lower mean levels of concurrent depressive symptoms (β = −1.04, 95% confidence interval: −1.73, −0.35) and were less likely to report a past-year suicide attempt (odds ratio = 0.37, 95% confidence interval: 0.14, 0.95) than women using low-efficacy contraception or no contraception, in models adjusted for propensity scores for hormonal contraceptive use. Longitudinal analyses indicated that associations between hormonal contraception and depressive symptoms were stable. Hormonal contraception may reduce levels of depressive symptoms among young women. Systematic investigation of exogenous hormones as a potential preventive factor in psychiatric epidemiology is warranted.
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Suicidal and Online: How Do Online Behaviors Inform Us of This High-Risk Population?
Keith Harris, John McLean & Jeanie Sheffield
Death Studies, forthcoming
Abstract:
To assist suicide prevention we need a better understanding of how suicidal individuals act in their environment, and the online world offers an ideal opportunity to examine daily behaviors. This anonymous survey (N = 1,016) provides first-of-its-kind empirical evidence demonstrating suicide-risk people (n = 290) are unique in their online behaviors. Suicidal users reported more time online, greater likelihood of developing online personal relationships, and greater use of online forums. In addition, suicide-risk women reported more time browsing/surfing and social networking. We conclude that suicide prevention efforts should respond to suicide-risk users’ greater demands for online interpersonal communications.
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Ethnicity Moderates the Association Between 5-HTTLPR and National Suicide Rates
Anne Schild et al.
Archives of Suicide Research, forthcoming
Abstract:
The association between ethnicity, national suicide rates, and the functional serotonin transporter gene polymorphism (5-HTTLPR), under consideration of the role of economic indicators, national alcohol intake, and national happiness scores was analyzed with an ecologic analysis. Data on allelic frequencies of the short (s) allele from 38 countries from over 100,000 healthy screened or general population individuals were analyzed with multiple regression models. Allele frequency varied widely both within and across ethnicities and an ethnicity-based interaction between national suicide rates and 5-HTTLPR allele frequency was revealed with the s allele acting as protective factor in Caucasian and as a risk factor in non-Caucasian populations. This interaction effect underlines the importance of ethnicity as a moderating factor in the genetics of suicide.
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Briana Mezuk, John Myers & Kenneth Kendler
American Journal of Public Health, October 2013, Pages S145-S151
Objectives: We tested 3 hypotheses — social causation, social drift, and common cause — regarding the origin of socioeconomic disparities in major depression and determined whether the relationship between socioeconomic status (SES) and major depression varied by genetic liability for major depression.
Methods: Data were from a sample of female twins in the baseline Virginia Adult Twin Study of Psychiatric and Substance Use Disorders interviewed between 1987 and 1989 (n = 2153). We used logistic regression and structural equation twin models to evaluate these 3 hypotheses.
Results: Consistent with the social causation hypothesis, education (odds ratio [OR] = 0.78; 95% confidence interval [CI] = 0.66, 0.93; P < .01) and income (OR = 0.93; 95% CI = 0.89, 0.98; P < .01) were significantly related to past-year major depression. Upward social mobility was associated with lower risk of depression. There was no evidence that childhood SES was related to development of major depression (OR = 0.98; 95% CI = 0.89, 1.09; P > .1). Consistent with a common genetic cause, there was a negative correlation between the genetic components of major depression and education (r2 = –0.22). Co-twin control analyses indicated a protective effect of education and income on major depression even after accounting for genetic liability.
Conclusions: This study utilized a genetically informed design to address how social position relates to major depression. Results generally supported the social causation model.
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Association between subjective and cortisol stress response depends on the menstrual cycle phase
Annie Duchesne & Jens Pruessner
Psychoneuroendocrinology, forthcoming
Abstract:
The relation between the physiologic and subjective stress responses is inconsistently reported across studies. Menstrual cycle phases variations have been found to influence the psychophysiological stress response; however little is known about possible cycle phase differences in the relationship between physiological and subjective stress responses. This study examined the effect of menstrual cycle phase in the association between subjective stress and physiological response. Forty-five women in either the follicular (n = 21) or the luteal phase of the menstrual cycle were exposed to a psychosocial stress task. Salivary cortisol, cardiovascular, and subjective stress were assessed throughout the experiment. Results revealed a significant group difference in the association between peak levels of cortisol and post task subjective stress. In women in the follicular phase a negative association was observed (r2 = .199 p= 0.04), while this relation was positive in the group of women in the luteal phase (r2= .227 p = 0.02). These findings suggest a possible role of sex hormones in modulating the cortisol stress response function in emotion regulation.
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Tegan Cruwys et al.
Social Science & Medicine, forthcoming
Abstract:
A growing body of research suggests that a lack of social connectedness is strongly related to current depression and increases vulnerability to future depression. However, few studies speak to the potential benefits of fostering social connectedness among persons already depressed or to the protective properties of this for future depression trajectories. We suggest that this may be in part because connectedness tends to be understood in terms of (difficult to establish) ties to specific individuals rather than ties to social groups. The current study addresses these issues by using population data to demonstrate that the number of groups that a person belongs to is a strong predictor of subsequent depression (such that fewer groups predicts more depression), and that the unfolding benefits of social group memberships are stronger among individuals who are depressed than among those who are non-depressed. These analyses control for initial group memberships, initial depression, age, gender, socioeconomic status, subjective health status, relationship status and ethnicity, and were examined both proximally (across 2 years, N=5055) and distally (across 4 years, N=4087). Depressed respondents with no group memberships who joined one group reduced their risk of depression relapse by 24%; if they joined three groups their risk of relapse reduced by 63%. Together this evidence suggests that membership of social groups is both protective against developing depression and curative of existing depression. The implications of these results for public health and primary health interventions are discussed.
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Prevalence of mental health disorders among low-income African American adolescents
Gayle Byck et al.
Social Psychiatry and Psychiatric Epidemiology, October 2013, Pages 1555-1567
Purpose: Data on the prevalence of mental health disorders for low-income, urban African American adolescents are scarce. This study presents data about the burden of mental disorders for this understudied population.
Methods: Mental disorders were assessed using the Diagnostic Interview Schedule for Children (C-DISC), Youth Self-Report (YSR), and Child Behavior Checklist (CBCL) among a sample of adolescents and their caregivers from very impoverished neighborhoods in a Southern city.
Results: Based on the C-DISC, 3.8, 5.1 and 7.7 % of adolescents met diagnostic criteria for major depression, post-traumatic stress disorder, and conduct disorder, respectively. There were significant differences among some of the mental health disorders based on adolescent and caregiver characteristics such as sex, school status, caregiver work status, and income level. We found a low prevalence of alcohol, marijuana, and substance abuse and dependence disorders.
Conclusions: Information about the prevalence of mental health disorders in specific communities and populations can assist in addressing unmet needs, planning for services and treatment, and reducing health disparities.
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Exploring The Intergenerational Persistence Of Mental Health: Evidence From Three Generations
David Johnston, Stefanie Schurer & Michael Shields
Journal of Health Economics, December 2013, Pages 1077–1089
Abstract:
This paper uses data from the 1970 British Cohort Study to quantify the intergenerational persistence of mental health, and the long-run economic costs associated with poor parental mental health. We find a strong and significant intergenerational correlation that is robust to different covariate sets, sample restrictions, model specifications and potential endogeneity. Importantly, the intergenerational persistence is economically relevant, with maternal mental health associated with lasting effects on the child's educational attainment, future household income and the probability of having criminal convictions. These results do not disappear after controlling for children's own childhood and adulthood mental health.
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Sex Differences in the Persistence of the Amygdala Response to Negative Material
Joseph Andreano, Bradford Dickerson & Lisa Feldman Barrett
Social Cognitive and Affective Neuroscience, forthcoming
Abstract:
Previous studies have indicated that men and women have different amygdala responses to novel (vs familiar) and valenced (positive vs negative) material. It is not known, however, whether these affective sex differences are related. In this study, we tested whether women have more persistent amygdala responses to familiar, negative material than men do. During fMRI, male and female participants viewed evocative images that varied in novelty and valence. Women and men showed equivalent responses to novel negative material, but women showed a sustained amygdala response to familiar negative material relative to men, indicating that women's amygdala responses were more persistent over multiple repetitions of negative material. Individuals with more persistent amygdala responses also reported greater levels of negative affect. These findings have implications for sex differences in the incidence of affective disorders.
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Impact of civil war on emotion recognition: The denial of sadness in Sierra Leone
Maria Allessandra Umiltà et al.
Frontiers in Psychology, September 2013
Abstract:
Studies of children with atypical emotional experience demonstrate that childhood exposure to high levels of hostility and threat biases emotion perception. This study investigates emotion processing, in former child soldiers and non-combatant civilians. All participants have experienced prolonged violence exposure during childhood. The study, carried out in Sierra Leone, aimed to examine the effects of exposure to and forced participation in acts of extreme violence on the emotion processing of young adults war survivors. A total of 76 young, male adults (38 former child soldier survivors and 38 civilian survivors) were tested in order to assess participants' ability to identify four different facial emotion expressions from photographs and movies. Both groups were able to recognize facial expressions of emotion. However, despite their general ability to correctly identify facial emotions, participants showed a significant response bias in their recognition of sadness. Both former soldiers and civilians made more errors in identifying expressions of sadness than in the other three emotions and when mislabeling sadness participants most often described it as anger. Conversely, when making erroneous identifications of other emotions, participants were most likely to label the expressed emotion as sadness. In addition, while for three of the four emotions participants were better able to make a correct identification the greater the intensity of the expression, this pattern was not observed for sadness. During movies presentation the recognition of sadness was significantly worse for soldiers. While both former child soldiers and civilians were found to be able to identify facial emotions, a significant response bias in their attribution of negative emotions was observed. Such bias was particularly pronounced in former child soldiers. These findings point to a pervasive long-lasting effect of childhood exposure to violence on emotion processing in later life.
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Perceived control: A general psychological vulnerability factor for hoarding
Amanda Raines et al.
Personality and Individual Differences, January 2014, Pages 175–179
Abstract:
Perceived control, the degree to which the environment is believed to be within an individual’s control, has been identified as a key vulnerability factor among numerous anxiety conditions. Specifically, it has been suggested that a sense of uncontrollability over potentially threatening events and emotions leads to increased fear and avoidance behaviors. Patterns of behavioral avoidance are central to theoretical models and observations of hoarding. However, no studies to date have examined the associations between perceived control and hoarding. The primary aim of the current study was to examine relationships between perceived control and hoarding behaviors. Participants consisted of undergraduate students (N = 180). As predicted, perceived control was significantly associated with increased hoarding severity even after controlling for overall negative affect. In addition, perceived control was significantly associated with several more specific hoarding behaviors including acquiring and difficulty discarding. When examining specific perceived control subfactors, only the threat control subfactor was associated with increased hoarding severity. The current study supports previous research suggesting that diminished perceived control over aversive events is central to the development and maintenance of numerous anxiety-related conditions. Moreover, the current study adds to a growing body of literature identifying potential risk factors for hoarding.
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Sustained Striatal Activity Predicts Eudaimonic Well-Being and Cortisol Output
Aaron Heller et al.
Psychological Science, forthcoming
Abstract:
Eudaimonic well-being — a sense of purpose, meaning, and engagement with life — is protective against psychopathology and predicts physical health, including lower levels of the stress hormone cortisol. Although it has been suggested that the ability to engage the neural circuitry of reward may promote well-being and mediate the relationship between well-being and health, this hypothesis has remained untested. To test this hypothesis, we had participants view positive, neutral, and negative images while fMRI data were collected. Individuals with sustained activity in the striatum and dorsolateral prefrontal cortex to positive stimuli over the course of the scan session reported greater well-being and had lower cortisol output. This suggests that sustained engagement of reward circuitry in response to positive events underlies well-being and adaptive regulation of the hypothalamic-pituitary-adrenal axis.
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Eva Loth et al.
Biological Psychiatry, forthcoming
Background: Common variants in the oxytocin receptor gene (OXTR) have been shown to influence social and affective behavior and to moderate the effect of adverse experiences on risk for social-affective problems. However, the intermediate neurobiological mechanisms are not fully understood. Although human functional neuroimaging studies have reported that oxytocin effects on social behavior and emotional states are mediated by amygdala function, animal models indicate that oxytocin receptors in the ventral striatum (VS) modulate sensitivity to social reinforcers. This study aimed to comprehensively investigate OXTR-dependent brain mechanisms associated with social-affective problems.
Methods: In a sample of 1445 adolescents we tested the effect of 23-tagging single nucleotide polymorphisms across the OXTR region and stressful life events (SLEs) on functional magnetic resonance imaging blood oxygen level–dependent activity in the VS and amygdala to animated angry faces. Single nucleotide polymorphisms for which gene-wide significant effects on brain function were found were then carried forward to examine associations with social-affective problems.
Results: A gene-wide significant effect of rs237915 showed that adolescents with minor CC-genotype had significantly lower VS activity than CT/TT-carriers. Significant or nominally significant gene × environment effects on emotional problems (in girls) and peer problems (in boys) revealed a strong increase in clinical symptoms as a function of SLEs in CT/TT-carriers but not CC-homozygotes. However, in low-SLE environments, CC-homozygotes had more emotional problems (girls) and peer problems (boys). Moreover, among CC-homozygotes, reduced VS activity was related to more peer problems.
Conclusions: These findings suggest that a common OXTR-variant affects brain responsiveness to negative social cues and that in “risk-carriers” reduced sensitivity is simultaneously associated with more social-affective problems in “favorable environments” and greater resilience against stressful experiences.
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Inflammatory dietary pattern and risk of depression among women
Michel Lucas et al.
Brain, Behavior, and Immunity, forthcoming
Backround: Inflammation is considered as a mechanism leading to depression, but the association between inflammatory dietary pattern and depression risk is unknown.
Methods: Using reduced-rank regression, we identified a dietary pattern that was related to plasma levels of inflammatory markers (C-reactive protein, interleukin-6, tumor necrosis factor receptor 2), and we conducted a prospective analysis of the relationship of this pattern and depression risk among participants in the Nurses’ Health Study. A total of 43,685 women (aged 50−77) without depression at baseline (1996) were included and followed up until 2008. Diet information was obtained from food frequency questionnaires completed between 1984 through 2002 and computed as cumulative average of dietary intakes with a 2-year latency applied. We used a strict definition of depression that required both self-reported physician-diagnosed depression and use of antidepressants, and a broader definition that included women who reported either clinical diagnosis or antidepressant use.
Results: During the 12-year follow-up, we documented 2,594 incident cases of depression using the stricter definition and 6,446 using the broader definition. After adjustment for body mass index and other potential confounders, relative risks comparing extreme quintiles of the inflammatory dietary pattern were 1.41 (95% confidence interval [CI], 1.22, 1.63; P-trend <.001) for the strict definition and 1.29 (95% CI, 1.18, 1.41; P-trend <.001) for the broader definition of depression.
Conclusions: The inflammatory dietary pattern is associated with a higher depression risk. This finding suggests that chronic inflammation may underlie the association between diet and depression.
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Cortisol and PTSD Symptoms Among Male and Female High-Exposure 9/11 Survivors
Sharon Dekel et al.
Journal of Traumatic Stress, forthcoming
Abstract:
Only a few studies have examined cortisol response to trauma-related stressors in relation to posttraumatic stress disorder (PTSD). We followed a sample of high-exposure survivors of the attacks on September 11, 2001 (9/11; 32 men and 29 women) and examined their cortisol response after recalling the escape from the attack, 7 and 18 months post-9/11. PTSD symptoms and saliva cortisol levels were assessed before and after trauma recollection. Hierarchical regression analyses revealed that PTSD symptoms and male sex predicted increased cortisol response following recollections. For men, elevated cortisol was associated with greater severity of reexperiencing symptoms (p < .001) and lower severity of avoidance symptoms (p < .001). For women, recall-induced cortisol was minimal and unrelated to PTSD symptoms (p = .164 and p = .331, respectively). These findings suggest that augmented cortisol response to trauma-related stressors may be evident in men reporting symptoms of PTSD. Thus, as cortisol abnormalities related to PTSD symptoms appear sex-specific, future research on mechanisms of sex differences in response to trauma is warranted.
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Karen Pang & Theodore Beauchaine
Developmental Psychobiology, November 2013, Pages 698–706
Abstract:
Conduct disorder (CD) and depression co-occur at far greater levels than chance, despite largely separate diagnostic criteria. One potential shared mechanism of this comorbidity is emotion dysregulation, which characterizes both internalizing and externalizing disorders. Previous research demonstrates that respiratory sinus arrhythmia (RSA) — a peripheral biomarker of emotion regulation — is attenuated among children with CD, and among children with depression. However, few studies have examined biomarkers of emotion regulation as a function of heterotypic comorbidity. We evaluated longitudinal patterns of RSA and RSA reactivity to emotion evocation across three annual assessments among 207 children diagnosed at ages 8–12 years with CD (n = 30), depression (n = 28), comorbid CD and depression (n = 80), or no psychiatric condition (n = 69). Using continuous symptom counts as predictors, Depression × CD interactions were observed for both Time 1 resting RSA and Time 1 RSA reactivity. CD, depression, and their interaction were all associated with low resting RSA at Time 1. In addition, concurrently elevated CD and depression scores predicted the greatest RSA reactivity to emotion evocation. Psychopathology scores were unrelated to developmental changes in RSA and RSA reactivity over time.