Recent developments in understanding the psychosocial aspects of depression

Abnormal asymmetry of N200 and P300 event-related potentials in subclinical depression

Sex differences for depression in prevalence and symptom profile may in part be due to differences between men and women in brain dysfunction associated with the disorder. Changes in event-related potential (ERP) measures similar to those seen in clinical populations are reported in subclinical or premorbid forms of depression. The current study investigates sex differences in ERPs associated with subclinical depression. One-hundred-and-forty healthy, right-handed adults (aged 20-60 years; screened to exclude clinical depression and psychosis) completed an auditory oddball task and the Depression Anxiety and Stress Scale (DASS). Seventy (n = 35 men) subclinically depressed (SD) (i.e. scoring >2 for depression on DASS) participants were matched for age and education with 70 (n = 35 men) participants showing no signs of depression (ND). Repeated measures multivariate analysis of variance was used to test for differences in N200 and P300 amplitude between SD and ND groups. ND, but not SD groups had asymmetry (R > L) of central N200 amplitude. Similar asymmetry was seen in ND, but not SD men at posterior sites. SD groups demonstrated left > right posterior P300 amplitude asymmetry due to P300 enhancement at left temporoparietal sites. Results support involvement of various cognitive mechanisms measured by P300 and N200 in subclinical depressive symptoms some of which may rely on sex.

A pilot study of adjunctive family psychoeducation in adolescent major depression: feasibility and treatment effect

OBJECTIVE

To obtain preliminary evidence of the feasibility and effectiveness of adjunctive family psychoeducation in adolescent major depressive disorder.

METHOD

Participants were from outpatient clinics in Hamilton and London, Ontario. Over 24 months, 41 adolescents ages 13 through 18 years meeting major depressive disorder criteria were recruited (31 in Hamilton, 10 in London). Participants were randomized to usual treatment or usual treatment plus family psychoeducation. Outcome measures were readministered at 2 weeks, mid-treatment, posttreatment, and 3-month follow-up. Intent-to-treat analyses used chi2 and t tests and growth curve analysis. Standardized effects based on growth curve estimates were calculated for continuous outcomes.

RESULTS

The London site was withdrawn because of poor participant retention. In Hamilton, no participant missed more than one assessment and there was good family psychoeducation adherence. Compared to controls, participants in the experimental group showed greater improvement in social functioning and adolescent-parent relationships (with medium standardized effect size > 0.5), and parents reported greater satisfaction with treatment.

CONCLUSIONS

There were positive treatment effects on family and social functioning processes postulated to mediate the clinical course of major depressive disorder. The study provides support for further evaluation of family psychoeducation in this clinical population.

Housing improvement and self-reported mental distress among council estate residents

This paper is concerned with how housing improvements instigated either publicly or privately influence the degree of psychological stress reported by council estate residents in South Manchester. Stress is measured on the GHQ12 scale containing standard symptomatic items. Potential sources of variation in this indicator are analysed within a geographical setting where repeated samples of residents were drawn from two adjacent suburban council housing estates before and after the implementation of a single regeneration budget (SRB) housing initiative in late 1999. The residents of one of these estates (Wythenshawe) were targeted by this funding while those in the other (Mersey Bank) were not. The latter, therefore, serve as a control for the effects of the enhanced incidence of housing improvement activity promoted by this SRB. Regression analyses revealed that stress was raised significantly among the SRB residents perhaps on account of the additional environmental nuisance they encountered. The experience of stress among all residents, however, was dominated by measures of personal psychosocial risk and it is argued that future regeneration initiatives should address the manifestation of these risks in the effort to achieve better mental health.

Human gender differences in an emotional visual oddball task: an event-related potentials study

Pictures from the Ekman and Friesen series were used in an event-related potentials study to define the timing of occurrence of gender differences in the processing of positive (happy) and negative (fear) facial expressions. Ten male and 10 female volunteers were confronted with a visual oddball design, in which they had to detect, as quickly as possible, deviant happy or fearful faces amongst a train of standard stimuli (neutral faces). Behavioral results suggest that men and women detected fearful faces more quickly than happy ones. The main result is that the N2b component, functionally considered as an attentional orienting mechanism, was delayed in men for happy stimuli as compared with fearful ones. Gender differences observed in the processing of emotional stimuli could then originate at the attentional level of the information processing system.

Depression and obesity

The prevalence of depression (10%) and overweight (65%) indicates that there is a probability that they will co-occur, but are they functionally related? This report used the moderator/mediator distinction to approach this question. Moderators, such as severity of depression, severity of obesity, gender, socioeconomic status (SES), gene-by-environment interactions and childhood experiences, specify for whom and under what conditions effects of agents occur. Mediators, such as eating and physical activity, teasing, disordered eating and stress, identify why and how they exert these effects. Major depression among adolescents predicted a greater body mass index (BMI = kg/m(2)) in adult life than for persons who had not been depressed. Among women, obesity is related to major depression, and this relationship increases among those of high SES, while among men, there is an inverse relationship between depression and obesity, and there is no relationship with SES. A genetic susceptibility to both depression and obesity may be expressed by environmental influences. Adverse childhood experiences promote the development of both depression and obesity, and, presumably, their co-occurrence. As most knowledge about the relationship between these two factors results from research devoted to other topics, a systematic exploration of this relationship would help to elucidate causal mechanisms and opportunities for prevention and treatment.

Depression and cardiovascular disease: mechanisms of interaction

This article explores the relationship between depression and cardiovascular disease from a mechanistic standpoint. Depression and cardiovascular disease are two of the most prevalent health problems in the United States and are the two leading causes of disability both in the United States and worldwide. Although depression is a known risk factor for the development of cardiovascular disease, as well as an independent predictor of poor prognosis following a cardiac event, the mechanistic relationship between the two remains unclear. Depression is associated with changes in an individual's health status that may influence the development and course of cardiovascular disease, including noncompliance with medical recommendations, as well as the presence of cardiovascular risk factors such as smoking and hypertension. In addition, depression is associated with physiologic changes, including nervous system activation, cardiac rhythm disturbances, systemic and localized inflammation, and hypercoagulability, that negatively influence the cardiovascular system. Further, stress may be an underlying trigger that leads to the development of both depression and cardiovascular disease. This article reviews seven potential mechanisms for the relationship between depression and cardiovascular disease and presents the available evidence surrounding each mechanism. Finally, future directions for research are discussed.

Additive effects of cognitive function and depressive symptoms on mortality in elderly community-living adults

BACKGROUND

Poor cognitive function and depressive symptoms are common in the elderly, frequently coexist, and are interrelated. Both risk factors are independently associated with mortality. Few studies have comprehensively described how the combination of poor cognitive function and depressive symptoms affect the risk for mortality. Our aim was to examine whether the combination of varying levels of cognitive function and depressive symptoms affect the risk of mortality in community-living elderly adults.

METHODS

We studied 6301 elderly adults (mean age, 77 years; 62% women; 81% white) enrolled in the Asset and Health Dynamics Among the Oldest Old (AHEAD) study, a prospective study of community-living participants conducted from 1993 to 1995. Cognitive function and depressive symptoms were measured using two validated measures developed for the AHEAD study. On each measure, participants were divided into tertiles representing the best, middle, and worst scores, and then placed into one of nine mutually exclusive groups ranging from best functioning on both measures to worst functioning on both measures. Mortality rates were assessed in each of the nine groups. Cox proportional hazards models were used to control for potentially confounding characteristics such as demographics, education, income, smoking, alcohol consumption, comorbidity, and baseline functional impairment.

RESULTS

During 2 years of follow-up, 9% (548) of the participants died. Together, cognitive function and depressive symptoms differentiated between elderly adults at markedly different risk for mortality, ranging from 3% in those with the best function on both measures to 16% in those with the worst function on both measures (p <.001). Furthermore, for each level of cognitive function, more depressive symptoms were associated with higher mortality rates, and for each level of depressive symptoms, worse cognitive function was associated with higher mortality rates. In participants with the best cognitive function, mortality rates were 3%, 5%, and 9% in participants with low, middle, and high depressive symptoms, respectively (p <.001 for trend). The corresponding rates were 6%, 7%, and 12% in participants with the middle level of cognitive function (p <.001 for trend), and 10%, 13%, and 16% in participants with the worst level of cognitive function (p <.001 for trend). After adjustment for confounders, participants with the worst function on both measures remained at considerably higher risk for death than participants with the best function on both measures (adjusted hazard ratio, 3.1; 95% confidence interval, 2.0-4.7).

CONCLUSIONS

Cognitive function and depressive symptoms can be used together to stratify elderly adults into groups that have significantly different rates of death. These two risk factors are associated with an increased risk in mortality in a progressive, additive manner.