One of the principal theories regarding the biological basis of Major Depressive Disorder (MDD) implicates a dysregulation of emotion processing circuitry. Gender differences in how emotions are processed and relative experience with emotion processing might help to explain some of the disparities in the prevalence of MDD between women and men. The current study sought to explore how gender and depression status relate to emotion processing.
This study employed a 2 (MDD status) × 2 (gender) factorial design to explore differences in classifications of posed facial emotional expressions (N = 151).
For errors, there was an interaction between gender and depression status. Women with MDD made more errors than did non-depressed women and men with MDD, particularly for fearful and sad stimuli (ps < .02), which they were likely to misinterpret as angry (ps < .04). There was also an interaction of diagnosis and gender for response cost for negative stimuli, with significantly greater interference from negative faces present in women with MDD compared with non-depressed women (p = .01). Men with MDD, conversely, performed similarly to control men (p = .61).
These results provide novel and intriguing evidence that depression in younger adults (< 35 years) differentially disrupts emotion processing in women as compared to men. This interaction could be driven by neurobiological and social learning mechanisms, or interactions between them, and may underlie differences in the prevalence of depression in women and men.
psychiatric disorders; affect perception; sex differences
Desensitization of serotonin 1A (HTR1A) and 1B (HTR1B) autoreceptors has been proposed to be involved in the delayed onset of response to SSRIs. Variations in gene expression in these genes may thus affect SSRI response. Here we test this hypothesis in two samples from the Sequenced Treatment Alternatives to Relieve Depression (STAR*D), and show evidence for involvement of several genetic variants alone and in interaction. Initially, three functional SNPs in the HTR1B gene and in the HTR1A gene were analyzed in 153 depressed patients treated with citalopram. QIDS-C scores were evaluated over time with respect to genetic variation. Subjects homozygous for the - 1019 G allele (rs6295) in HTR1A showed higher baseline QIDS scores (p = 0.033), and by 12 weeks had a significantly lower response rate (p = 0.005). HTR1B haplotypes were estimated according to previously reported in-vitro expression levels. Individuals who were homozygous for the high-expression haplotype showed significantly slower response to citalopram (p = 0.034).
We then analyzed more SNPs in the extended overall STAR*D sample. Although we could not directly test the same functional SNPs, we found that homozygotes for the G allele at rs1364043 in HTR1A (p = 0.045) and the C allele of rs6298 in HTR1B showed better response to citalopram over time (p = 0.022). Test for interaction between rs6298 in HTR1B and rs1364043 in HTR1A was significant (overall p = 0.032)
Our data suggest that an enhanced capacity of HTR1B or HTR1A transcriptional activity may impair desensitization of the autoreceptors during SSRI treatment.
SSRI; depression; haplotype; HTR1B; HTR1A; association
Examine the diurnal variation of salivary cortisol in adults with spinal cord injury (SCI) and the effect of stressors on cortisol and mood.
Ecological momentary assessment (EMA) to capture cortisol, stress and mood from 25 persons with SCI and 26 without SCI. Data were analyzed using linear mixed models.
There were no systematic differences between groups on missing data. Diurnal variation of cortisol of participants with SCI reflected an expected pattern. No significant group differences for cortisol diurnal pattern, stress or mood; when group interactions were significant, results indicated lower cortisol reactivity to stress in participants with SCI. Stress had a significant impact on positive, negative and agitated moods.
Stress in daily life and its association with cortisol and mood were largely similar between persons with and without SCI. A key methodological contribution is the demonstration of using EMA to collect biological and behavioral data in the field from participants with SCI. The use of EMA in rehabilitation psychology research has great potential to advance our understanding of the dynamics of daily life with disability.
spinal cord injuries; stress, psychological; hydrocortisone; ecological momentary assessment
Inhibitory control or regulatory difficulties have been explored in major depressive disorder (MDD) but typically in the context of affectively salient information. Inhibitory control is addressed specifically by using a task devoid of affectively-laden stimuli, to disentangle the effects of altered affect and altered inhibitory processes in MDD.
Twenty MDD and 22 control volunteer participants matched by age and gender completed a contextual inhibitory control task, the Parametric Go/No-go (PGNG) task during functional magnetic resonance imaging. The PGNG includes three levels of difficulty, a typical continuous performance task and two progressively more difficult versions including Go/No-go hit and rejection trials. After this test, 15 of 20 MDD patients completed a full 10-week treatment with s-citalopram.
There was a significant interaction among response time (control subjects better), hits (control subjects better), and rejections (patients better). The MDD participants had greater activation compared with the control group in frontal and anterior temporal areas during correct rejections (inhibition). Activation during successful inhibitory events in bilateral inferior frontal and left amygdala, insula, and nucleus accumbens and during unsuccessful inhibition (commission errors) in rostral anterior cingulate predicted post-treatment improvement in depression symptoms.
The imaging findings suggest that in MDD subjects, greater neural activation in frontal, limbic, and temporal regions during correct rejection of lures is necessary to achieve behavioral performance equivalent to control subjects. Greater activation in similar regions was further predictive of better treatment response in MDD.
Depression; executive functioning; fMRI; imaging; inhibitory control; mood disorders; SSRIs; treatment response
This paper draws together contributions to a scientific table discussion on obesity at the European Science Open Forum 2008 which took place in Barcelona, Spain. Socioeconomic dimensions of global obesity, including those factors promoting it, those surrounding the social perceptions of obesity and those related to integral public health solutions, are discussed. It argues that although scientific accounts of obesity point to large-scale changes in dietary and physical environments, media representations of obesity, which context public policy, pre-eminently follow individualistic models of explanation. While the debate at the forum brought together a diversity of views, all the contributors agreed that this was a global issue requiring an equally global response. Furthermore, an integrated ecological model of obesity proposes that to be effective, policy will need to address not only human health but also planetary health, and that therefore, public health and environmental policies coincide.
Controversy exists as to whether women with depression respond better to selective serotonin reuptake inhibitors (SSRIs) than men. The purpose of this report was to determine whether men and women differ in their responses to treatment with the SSRI citalopram using a large sample of real world patients from primary and psychiatric specialty care settings.
As part of the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study, 2876 participants were treated with citalopram for up to 12-14 weeks. Baseline demographic and clinical characteristics and outcomes were gathered and compared between men and women.
At baseline, women were younger, had more severe depressive symptoms and were more likely to have: early onset; previous suicide attempt(s); a family history of depression, alcohol abuse or drug abuse; atypical symptom features; and one or more of several concurrent psychiatric disorders. Despite greater baseline severity and more Axis I comorbidities, women were more likely to reach remission and response with citalopram than men.
Women have a better response to the SSRI citalopram than men, which may be due to sex-specific biological differences particularly in serotonergic systems.
antidepressants; gender differences; estradiol; women's health; depression
Epidemiological studies consistently show that circulating sex hormone binding globulin (SHBG) levels are lower in type 2 diabetes patients than non-diabetic individuals, but the causal nature of this association is controversial. Genetic studies can help dissect causal directions of epidemiological associations because genotypes are much less likely to be confounded, biased or influenced by disease processes. Using this Mendelian randomization principle, we selected a common single nucleotide polymorphism (SNP) near the SHBG gene, rs1799941, that is strongly associated with SHBG levels. We used data from this SNP, or closely correlated SNPs, in 27 657 type 2 diabetes patients and 58 481 controls from 15 studies. We then used data from additional studies to estimate the difference in SHBG levels between type 2 diabetes patients and controls. The SHBG SNP rs1799941 was associated with type 2 diabetes [odds ratio (OR) 0.94, 95% CI: 0.91, 0.97; P = 2 × 10−5], with the SHBG raising allele associated with reduced risk of type 2 diabetes. This effect was very similar to that expected (OR 0.92, 95% CI: 0.88, 0.96), given the SHBG-SNP versus SHBG levels association (SHBG levels are 0.2 standard deviations higher per copy of the A allele) and the SHBG levels versus type 2 diabetes association (SHBG levels are 0.23 standard deviations lower in type 2 diabetic patients compared to controls). Results were very similar in men and women. There was no evidence that this variant is associated with diabetes-related intermediate traits, including several measures of insulin secretion and resistance. Our results, together with those from another recent genetic study, strengthen evidence that SHBG and sex hormones are involved in the aetiology of type 2 diabetes.
The hypothalamic-pituitary adrenal (HPA) axis may mediate negative health effects of stress. It is sensitive to cognitive/emotional factors like novelty, perceived control and coping. Psychological intervention that reduces novelty, and enhances cognitive coping and sense of control can reduce cortisol responses to pentagastrin, a pharmacological HPA activator. This study attempted to identify the core factors that modulate HPA axis activity in this model.
Varying instructions were administered prior to drug exposure in a two-visit (placebo first) pentagastrin infusion paradigm. Healthy subjects (n=40) were randomly assigned to 1 of 4 instruction groups: (1) Standard instruction (SI); (2) Full cognitive intervention (CI); (3) The CI control component alone; or (4) The CI novelty reduction/coping components alone. Blood samples were obtained via intravenous catheter before and after pentagastrin.
Subjects receiving an intervention had smaller cortisol responses than subjects receiving standard instructions. “Coping” alone had as strong an impact as the more complex intervention that combined “coping” and “control.” “Control alone” also reduced cortisol but its HPA impact appeared less robust.
Brief psychological manipulation can significantly reduce HPA activation in challenge paradigms. Cognitive preparation that focused on side effects, reduced potential surprise and enhanced cognitive coping modulated HPA axis activity as effectively as a previously tested intervention that combined coping and control manipulations. A sense of control alone also reduced cortisol release. The results support development of “control” or “coping” techniques to combat negative health effects of stress that are mediated by HPA axis activation.
stress; cortisol; pentagastrin; control; coping; anxiety
While epidemiologic research consistently reports greater prevalence of major depressive disorder in women, small sample sizes in many studies do not allow for full elaboration of illness characteristics. This paper examines gender differences in terms of illness attributes in a cohort of 2541 outpatients from across the United States who enrolled in the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study.
Confirmatory analyses were performed in 2541 outpatients comparing men and women with regard to socio-demographic features, comorbid Axis I and Axis III conditions, and illness characteristics. Results were compared to those of our previous report on the initial population of the first 1500 individuals enrolled in STAR*D.
In both samples, nearly two-thirds of the sample (62.5%) were women. Women had greater symptom severity, but men had more episodes of major depression, despite no difference in the length of illness. No differences in age of onset emerged. As in the first cohort, women showed greater rates of an anxiety disorder, bulimia and somatoform disorder, as well as more past suicide attempts, while men showed more alcohol and substance abuse. Women reported more appetite, weight, hypersomnia, interpersonal sensitivity, gastrointestinal and pain complaints, and less suicidal ideation. Irritability was equally common in men and women.
This large analysis confirmed most of the clinical features and co-morbidities found to be more prevalent in the first cohort of women. Additionally, this analysis corroborated previous research suggesting higher rates of atypical and anxious depression in women, but refuted the notion of an “irritable depression” found in men. The report confirmed the 1.7:1 ratio for depression seen across genders in the National Comorbidity Survey.
Women; Depression; Prevalence; Gender
The epidemiology of obesity suggests that, for the majority of individuals, the disorder arises from an interaction between genetic predisposition and lifestyle behaviors such as dietary intake and physical activity. Unravelling the molecular basis of such interactions is complex but is becoming a realistic proposition as evidence emerges from whole genome association studies of genetic variants that are definitively associated with obesity. A range of possible study designs is available for investigating gene–lifestyle interaction, and the strengths and weaknesses of each approach are discussed in this article. Given the likely small main effect of common genetic variants and the difficulties in demonstrating associations of lifestyle factors with future risk of obesity, we would favor an analytical approach based on the clear specification of prior probabilities to reduce the likelihood of false discovery. Mixed approaches combining data from large-scale observational studies with smaller intervention trials may be ideal. In designing new studies to investigate these issues, a key choice is how precisely to quantify the important, but difficult to measure lifestyle behaviors. It is clear from power calculations that an approach based on enhancing precision of measurement of diet and physical activity is critical.
The high heritability of obesity coupled with the rapid increase in prevalence suggests that a combination of genetic and behavioral factors is critical to the etiology of obesity (1). It is easy to propose such a model for the development of obesity, but it is altogether much harder to identify the molecular mechanisms that underlie such a model. In this article, we review overall strategies and possible epidemiological study designs for investigating how genetic and behavioral risk factors combine to lead to excess weight gain.
The excess mortality associated with depressive disorders has been most often attributed to risks for suicide but diverse findings indicate that depressive disorders also increase risks for cardiovascular (CV) mortality. Among the possible mediators is the HPA-axis hyperactivity that characterizes many cases of relatively severe depressive disorder and severity is characteristic of psychotic depressive disorder.
The following describes a 17-year mortality follow-up of 54 patients with Research Diagnostic Criteria (RDC) psychotic major depression or schizoaffective, mainly affective, depression. All had baseline assessments that included a 1mg dexamethasone suppression test with post-dexamethasone samples at 8 a.m., 4 p.m. and 11 p.m.
Regression analyses showed that both greater age and higher maximum post-dexamethasone cortisol concentrations predicted deaths due to cardiovascular (CV) causes (t = 4.01, p < .001 and t = 3.03, p = .004, respectively); the 11 p.m. cortisol concentration predicted death due to suicide (t = 2.05, p = 0.048). The 4 who died from CV disease had a mean (SD) post-dexamethasone cortisol concentration of 18.0 (6.0) μg/dl while the mean (SD) value for the remaining 50 patients was 7.6 (6.6) μg/dl (t = 3.03, df = 53, p = 0.004). Regression analyses showed the 11 p.m. post-dexamethasone value to be predictive of suicide (t = 2.05, p = 0.048).
Conclusions should be tentative because an earlier follow-up of a more heterogeneous, but larger, sample did not find a relationship between DST results and CV mortality, and because only 4 CV deaths occurred in the present study. HPA-axis hyperactivity is probably only one of a number of factors that link depressive disorder to CV mortality.
Previous studies have suggested that a variant in the melanocortin-4 receptor (MC4R) gene is important in protecting against common obesity. Larger studies are needed, however, to confirm this relation.
We assessed the association between the V103I polymorphism in the MC4R gene and obesity in three UK population based cohort studies, totalling 8,304 individuals. We also did a meta-analysis of relevant studies, involving 10,975 cases and 18,588 controls, to place our findings in context.
In an analysis of all studies, individuals carrying the isoleucine allele had an 18% (95% CI 4-30%, p=0·015) lower risk of obesity compared with noncarriers. There was no heterogeneity among studies and no apparent publication bias.
This study confirms that the V103I polymorphism protects against human obesity at a population level. As such it provides proof of principle that specific gene variants may, at least in part, explain susceptibility and resistance to common forms of human obesity. A better understanding of the mechanisms underlying this association will help determine whether changes in MC4R activity have therapeutic potential.
The RacGAP molecule α2-chimaerin is implicated in neuronal signaling pathways required for precise guidance of developing corticospinal axons. We now demonstrate that a variant of Duane’s retraction syndrome, a congenital eye movement disorder in which affected individuals show aberrant development of axon projections to the extraocular muscles, can result from gain-of-function heterozygous missense mutations in CHN1 that increase α2-chimaerin RacGAP activity in vitro. A subset of mutations enhances α2-chimaerin membrane translocation and/or α2-chimaerin’s previously unrecognized ability to form a complex with itself. In ovo expression of mutant CHN1 alters the development of ocular motor axons. These data demonstrate that human CHN1 mutations can hyperactivate α2-chimaerin and result in aberrant cranial motor neuron development.
Hormone-based contraceptives affect mood in healthy women or in women with Premenstrual Dysphoric Disorder. No study has yet examined their association with mood in women with major depressive disorder (MDD). The purpose of this study was to determine whether estrogen-progestin combination or progestin-only contraceptives are associated with depression severity, function and quality of life, or general medical or psychiatric comorbidity in women with MDD.
This analysis focused on a large population of female outpatients less than 40 years of age with non-psychotic MDD who were treated in 18 primary and 23 psychiatric care settings across the United States, using data from the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study. Baseline demographic and clinical information was gathered and compared between three groups based on hormonal use: combination (estrogen-progestin)(N=232), progestin-only (N=58), and no hormone treatment (N=948).
Caucasians were significantly more likely to use combined hormone contraception. Women on progestin-only had significantly more general medical comorbidities; greater hypersomnia, weight gain and gastrointestinal symptoms; and worse physical functioning than women in either of the other groups. Those on combined hormone contraception were significantly less depressed than those with no hormone treatment by the 16-item Quick Inventory of Depressive Symptomatology - Self-Rated. The combined hormone group also demonstrated better physical functioning and less obsessive-compulsive disorder comorbidity than either of the other groups.
Synthetic estrogen and progestins may influence depressive and physical symptoms in depressed women.
Estradiol; Progesterone; Major Depression; Mood symptoms; Oral contraceptives; Norplant
Numerous studies suggest that increased central drive to the hypothalamic-pituitary adrenal axis occurs in patients with major depression. To determine if increased central drive occurs throughout the 24H, we evaluated ACTH secretion under metyrapone blockade of cortisol production. We collected blood every 10 minutes for measurement of ACTH and data were analyzed for ACTH pulsatility using the pulse detection algorithm deconvolution. We studied 28 patients with major depression and 28 age and sex matched control subjects, of which 9 pairs were men and 19 pairs were women. We found a significant group by sex interaction with number of ACTH pulses (p=.04); depressed men showed more ACTH pulses over 24H than matched control men (p=0.02). There was also a significant sex difference in AUC pulses with men showing a smaller AUC ACTH than women. Previous analyses of these data with RM-ANOVA showed a smaller ACTH response in depressed men compared to control men. These data suggest that pulsatility and mean ACTH levels are examining different aspects of HPA axis function, and that the types of HPA axis dysregulation in depression may differ between men and women.
depression; ACTH; Hormone pulsatility; stress; HPA axis; cortisol
The association between socioeconomic position in middle age and risk of subsequent, short-term weight gain is unknown. We therefore assessed this association in a prospective population based cohort study in Norfolk, UK.
We analysed data on 14,619 middle-aged men and women (aged between 40–75 at baseline) with repeated objective measures of weight and height at baseline (1993–1997) and follow up (1998–2000).
During follow up 5,064 people gained more than 2.5 kg. Compared with the highest social class, individuals in the lowest social class had around a 30% greater risk of gaining more than 2.5 kg (OR 1.29; 95% CI 1.11–1.51; p for trend = 0.002). This association remained statistically significant following adjustment for sex, age, baseline BMI, smoking, and follow up time (OR 1.25; CI 1.07–1.46; p for trend <0.001). We also found no material difference between unadjusted models and those including all confounders and potential mediators.
Individuals of low socioeconomic position are at greatest risk of gaining weight during middle age, which is not explained by classical correlates of socioeconomic position and risk factors for obesity.
Congenital fibrosis of the extraocular muscles types 1 and 3 (CFEOM1/CFEOM3) are autosomal dominant strabismus disorders that appear to result from maldevelopment of ocular nuclei and nerves. We previously reported that most individuals with CFEOM1 and rare individuals with CFEOM3 harbor heterozygous mutations in KIF21A. KIF21A encodes a kinesin motor involved in anterograde axonal transport, and the familial and de novo mutations reported to date predictably alter one of only a few KIF21A amino acids – three within the third coiled-coil region of the stalk and one in the distal motor domain, suggesting they result in altered KIF21A function. To further define the spectrum of KIF21A mutations in CFEOM we have now identified all CFEOM probands newly enrolled in our study and determined if they harbor mutations in KIF21A.
Sixteen CFEOM1 and 29 CFEOM3 probands were studied. Three previously unreported de novo KIF21A mutations were identified in three CFEOM1 probands, all located in the same coiled-coil region of the stalk that contains all but one of the previously reported mutations. Eight additional CFEOM1 probands harbored three of the mutations previously reported in KIF21A; seven had one of the two most common mutations, while one harbored the mutation in the distal motor domain. No mutation was detected in 5 CFEOM1 or any CFEOM3 probands.
Analysis of sixteen CFEOM1 probands revealed three novel KIF21A mutations and confirmed three reported mutations, bringing the total number of reported KIF21A mutations in CFEOM1 to 11 mutations among 70 mutation positive probands. All three new mutations alter amino acids in heptad repeats within the third coiled-coil region of the KIF21A stalk, further highlighting the importance of alterations in this domain in the etiology of CFEOM1.
The study of individuals at opposite ends of the HIV clinical spectrum can provide invaluable insights into HIV biology. Heterogeneity in criteria used to define these individuals can introduce inconsistencies in results from research and make it difficult to identify biological mechanisms underlying these phenotypes. In this systematic review, we formally quantified the heterogeneity in definitions used for terms referring to extreme phenotypes in the literature, and identified common definitions and components used to describe these phenotypes. We assessed 714 definitions of HIV extreme phenotypes in 501 eligible studies published between 1 January 2000 and 15 March 2012, and identified substantial variation among these. This heterogeneity in definitions may represent important differences in biological endophenotypes and clinical progression profiles of individuals selected by these, suggesting the need for harmonized definitions. In this context, we were able to identify common components in existing definitions that may provide a framework for developing consensus definitions for these phenotypes in HIV infection.
definitions; elite controllers; extreme-trait designs; HIV; HIV controllers; long-term nonprogressors; phenotypes; slow progressors; systematic review; viremic controllers