Protective factors against depression during the transition from adolescence to adulthood: findings from a national Canadian cohort.

OBJECTIVE: This study sought to identify factors protective against the onset or recurrence of depression in early adulthood, and to describe their interactions with stressors during this transitional period. METHODS: 1137 members of Canada's National Population Health Survey were followed from ages 12 to 17 in 1994/95 and contacted every two years until 2008/09. Protective factors measured at age 16/17 included social support, physical activity, mastery, self-esteem, and education level. General linear mixed models were used to examine the relationship between the protective factors and five assessments of depression, including interactions between protective factors and four types of stress: stressful life events, and work, financial, and personal stress. RESULTS: High mastery in adolescence had a significant protective effect against depression in early adulthood. Participants with high social support in adolescence were significantly less likely to become depressed after experiencing work or financial stress, compared to those with low social support. Those who were physically active in adolescence were less likely to become depressed after experiencing work stress, and higher overall education level reduced depression risk following personal stress or major life events. CONCLUSION: Social support and physical activity may be ideal targets for school-based depression interventions during a potentially stressful transitional period.

You are how you recruit: a cohort and randomized controlled trial of recruitment strategies.

BACKGROUND: Recruitment is a challenge in developing population-representative pregnancy and birth cohorts. METHODS: We developed a collaborative recruitment infrastructure (CRI) to recruit pregnant women for 4 pregnancy cohorts using: faxes from obstetrical offices, in-clinic recruiters, university and funder-driven free-media events, paid-media, and attendance at relevant tradeshows. Recruitment rates and demographic differences were compared between recruitment methods. RESULTS: We received 5008 referrals over 40 months. Compared to fax, free-media referrals were 13 times more likely to be recruited (OR 13.0, 95% CI 4.2, 40.4: p < 0.001) and paid-media referrals were 4 times more likely to be recruited (OR 4.6, 95% CI 2.1, 10.3: p < 0.001). Among paid-media advertisements, free-to-read print (e.g. Metro) was the most effective (OR 3.3, 95% CI 2.3, 4.5: p < 0.05). Several demographic differences were identified between recruitment methods and against a reference population. Between recruitment methods, media recruits had a similar proportion families with incomes ≥ $40,000 (paid-media: 94.4%; free-media: 93.3%) compared to fax recruits (95.7%), while in-clinic recruits were less likely to have family incomes ≥ $40,000 (88.8%, p < 0.05). Maternal recruits from fax and in-clinic were more likely to attend university (Fax: 92.6%, in-clinic 89.8%) versus the reference population (52.0%; p < 0.05 for both) and both were less likely to smoke (Fax: 6.8%, in-clinic 4.2%) versus reference (18.6%; p < 0.05 for both). However, while fax referrals were more likely to be Caucasian (85.9% versus reference 77.5%; p < 0.05), in-clinic referrals were not significantly different (78.2%; P > 0.05). CONCLUSION: Recruitment methods result in different recruitment rates and participant demographics. A variety of methods are required to recruit a generalizable sample.

Stress and development of depression and heavy drinking in adulthood: moderating effects of childhood trauma.

PURPOSE: Studies suggest that childhood trauma is linked to both depression and heavy drinking in adulthood, and may create a lifelong vulnerability to stress. Few studies have explored the effects of stress sensitization on the development of depression or heavy drinking among those who have experienced traumatic childhood events. This study aimed to determine the effect of childhood trauma on the odds of experiencing depression or heavy drinking in the face of an adult life stressor, using a large population-based Canadian cohort. METHODS: A total of 3,930 participants were included from the National Population Health Survey. The associations among childhood trauma, recent stress and depression/heavy drinking from 1994/1995 to 2008/2009 were explored using logistic regression, as were interactions between childhood trauma and recent stress. A generalized linear mixed model was used to determine the effects of childhood trauma and stressful events on depression/heavy drinking. Analyses were stratified by sex. RESULTS: Childhood trauma significantly increased the odds of becoming depressed (following 1 event: OR = 1.66; 95%CI 1.01, 2.71; 2+ events, OR = 3.89; 95%CI 2.44, 6.22) and drinking heavily (2+ events: OR = 1.79; 95%CI 1.03, 3.13). Recent stressful events were associated with depression, but not heavy drinking. While most interaction terms were not significant, in 2004/2005 the association between recent stress and depression was stronger in those who reported childhood trauma compared to those with no childhood trauma. CONCLUSIONS: Childhood trauma increases risk for both depression and heavy drinking. Trauma may moderate the effect of stress on depression; the relationship among trauma, stress and heavy drinking is less clear.

Predictors of long-term prognosis of depression.

BACKGROUND: Many people with depression experience repeated episodes. Previous research into the predictors of chronic depression has focused primarily on the clinical features of the disease; however, little is known about the broader spectrum of sociodemographic and health factors inherent in its development. Our aim was to identify factors associated with a long-term negative prognosis of depression. METHODS: We included 585 people aged 16 years and older who participated in the 2000/01 cycle of the National Population Health Survey and who reported experiencing a major depressive episode in 2000/01. The primary outcome was the course of depression until 2006/07. We grouped individuals into trajectories of depression using growth trajectory models. We included demographic, mental and physical health factors as predictors in the multivariable regression model to compare people with different trajectories. RESULTS: Participants fell into two main depression trajectories: those whose depression resolved and did not recur (44.7%) and those who experienced repeated episodes (55.3%). In the multivariable model, daily smoking (OR 2.68, 95% CI 1.54-4.67), low mastery (i.e., feeling that life circumstances are beyond one's control) (OR 1.10, 95% CI 1.03-1.18) and history of depression (OR 3.5, 95% CI 1.95-6.27) were significant predictors (p < 0.05) of repeated episodes of depression. INTERPRETATION: People with major depression who were current smokers or had low levels of mastery were at an increased risk of repeated episodes of depression. Future studies are needed to confirm the predictive value of these variables and to evaluate their accuracy for diagnosis and as a guide to treatment.

The Effects of Music-Contingent Gait Training on Cognition and Mood in Parkinson Disease: A Feasibility Study.

Background. In Parkinson disease (PD), gait impairments often coexist with nonmotor symptoms such as anxiety and depression. Biofeedback training may improve gait function in PD, but its effect on nonmotor symptoms remains unclear. This study explored the cognitive and global effects of Ambulosono, a cognitive gait training method utilizing step size to contingently control the real-time play of motivational music. Objective. This study examined the feasibility of music-contingent gait training and its effects on neuropsychological test performance and mood in persons with PD. Methods. A total of 30 participants with mild to moderate PD were semirandomized via sequential alternating assignment into an experimental training group or control music group. The training group received 12 weeks of music-contingent training, whereby music play was dependent on the user achieving a set stride length, adjusted online based on individual performance. The control group received hybrid training beginning with 6 weeks of noncontingent music walking, whereby music played continuously regardless of step size, followed by 6 weeks of music-contingent training. Global cognition, memory, executive function, attention, and working memory assessments were completed by blinded assessors at baseline, 6 weeks, and 12 weeks. Motor function, mood, and anxiety were assessed. Results. Average training adherence was 97%, with no falls occurring during training sessions. Improvements on cognitive measures were not clinically significant; however, significant decreases in depression and anxiety were observed in both groups over time (P < .05). Conclusions. Music-contingent gait training is feasible and safe in individuals with PD. Further investigation into potential therapeutic applications of this technology is recommended.

Postpartum depression, a direct and mediating risk factor for preschool wheeze in girls.

BACKGROUND: Postpartum depression affects over 1 in 10 child-bearing women. A growing body of evidence links maternal distress during the key developmental stages of infants with poor health outcomes, including wheeze and asthma. OBJECTIVE: We sought to investigate whether postpartum depression had an independent association with the development of wheeze in preschool-aged children. A second a priori objective was to ascertain whether postpartum depression functioned as a mediating factor for associations between wheeze, and prenatal distress and nutrition. METHODS: Data from the Community Perinatal Care Trial on maternal postpartum depression (Edinburgh Postnatal Depression Scale), the dependent variable, wheeze at age 3, and possible confounding factors were obtained for 791 women and their children in Calgary, Canada. Adjusted gender-specific logistic regression analyses were performed to test the association between postpartum depression and child wheeze, which was independent of maternal distress and vitamin use during pregnancy, pre/postnatal smoking, preterm birth, exclusive breastfeeding duration, daycare attendance, and maternal education. The potential mediating effects of postpartum depression were investigated in a path analysis. RESULTS: Wheeze at age 3 was almost 5 times more likely in girls of mothers who experienced postpartum depression. Results from a path analysis suggested that postpartum depression has a direct effect on wheeze (beta-coefficient=0.135, P < 0.05), and also mediates the effects of prenatal distress and vitamin use on wheeze in preschool girls. In boys, only prenatal smoking was a statistically significant predictor of wheeze, mainly through the effects of postnatal smoking. CONCLUSIONS & CLINICAL RELEVANCE: Postpartum depression may be a risk factor for preschool wheeze among girls in a low risk population, directly and indirectly through prenatal distress and vitamin use. Interventions which target postpartum depression and promote a healthy pregnancy may also reduce the risk of wheeze in children.

Exposure to Beta-(1,3)-D-glucan in house dust at age 7-10 is associated with airway hyperresponsiveness and atopic asthma by age 11-14.

BACKGROUND: Mould exposure has been linked to childhood asthma and bronchial hyper-responsiveness. Few studies have assessed beta-(1,3)-d-glucan (beta-glucan), a significant fungal cell wall constituent, in relation to asthma in adolescence. OBJECTIVE: To determine whether house dust-derived beta-glucan exposure at age 7-10 is associated with the development and persistence of atopic and non-atopic asthma, and bronchial hyper-responsiveness (BHR) by age 11-14. METHODS: Dust samples were collected from the 1995 Study of Asthma, Genes, and Environment (SAGE) birth cohort. This cohort was derived from Manitoba provincial healthcare administrative records of children high and low risk for asthma. Samples were collected from the homes of 422 children at age 7-10 and analyzed using beta-glucan and endotoxin-specific Limulus Amoebocyte Lysate assays. Asthma, atopy, and BHR status of each child were also assessed at ages 7-10 and 11-14. RESULTS: At age 7-10, beta-glucan dust levels in the home were associated with persistent atopic asthma at age 11-14 (OR 1.79 for each unit increase in levels, 95% CI 1.14-2.81), independent of endotoxin exposure, and Alternaria or Cladosporium sensitization. The likelihood of BHR almost doubled with unit increases in dust beta-glucan in asthmatic children. In children without asthma, exposure to high beta-glucan levels at age 7-10 also elevated risk for BHR in adolescence (OR 1.74, 95% CI 1.05-2.89). New-onset atopic asthma was twice more likely following high beta-glucan exposure in children without asthma but the association did not reach statistical significance. No associations were evident with concurrent asthma phenotype at age 7-10 or non-atopic asthma at age 11-14. CONCLUSION: These findings implicate home beta-glucan exposure at school-age as a risk factor for persistent atopic asthma and new-onset BHR. The higher prevalence of BHR in urban adolescents may be propagated by this home exposure.

The contribution of stress to the comorbidity of migraine and major depression: results from a prospective cohort study.

OBJECTIVES: To assess how much the association between migraine and depression may be explained by various measures of stress. DESIGN: National Population Health Survey is a prospective cohort study representative of the Canadian population. Eight years of follow-up time were used in the present analyses. SETTING: Canadian adult population ages 18-64. PARTICIPANTS: 9288 participants. OUTCOME: Incident migraine and major depression. RESULTS: Adjusting for sex and age, depression was predictive of incident migraine (HR: 1.62; 95% CI 1.03 to 2.53) and migraine was predictive of incident depression (HR: 1.55; 95% CI 1.15 to 2.08). However, adjusting for each assessed stressor (childhood trauma, recent marital problems, recent unemployment, recent household financial problems, work stress, chronic stress and change in social support) decreased this association, with chronic stress being a particularly strong predictor of outcomes. When adjusting for all stressors simultaneously, both associations were largely attenuated (depression-migraine HR: 1.30; 95% CI 0.80 to 2.10; migraine-depression HR: 1.19; 95% CI 0.86 to 1.66). CONCLUSIONS: Much of the apparent association between migraine and depression may be explained by stress.

Social, demographic, and health outcomes in the 10 years following adolescent depression.

PURPOSE: Little attention has been paid to the sociodemographic profiles of depressed youth during the vulnerable transition from adolescence to early adulthood. This study aimed to determine and describe the social, demographic, and health outcomes of adolescent depression during a 10-year period of transition into early adulthood, using a population-based cohort of Canadian teenagers. METHODS: Depression status on 1,027 adolescents aged 16-17 years was ascertained from the National Population Health Survey. Social and health outcomes (i.e., employment status, marital status, personal income, education, social support, self-perceived stress, heavy drinking, smoking, migraine headaches, adult depression, antidepressant use, self-rated health, and physical activity) were measured every 2 years until the ages of 26-27 years. Logistic regression was combined with a generalized linear mixed-model approach to determine the odds of health and social outcomes in depressed versus nondepressed adolescents. RESULTS: Proximal effects of adolescent depression were observed (at ages 18-19) on all outcomes with the exception of physical activity. Significant effects that persisted after 10 years included depression recurrence, higher severity of symptoms, migraine headaches, poor self-rated health, and low levels of social support. Adolescent depression did not appear to significantly affect employment status, personal income, marital status, or educational attainment. CONCLUSIONS: The transition from adolescence to adulthood is a particularly vulnerable period due to educational, employment, and social changes that may be occurring. The results of this study indicate that the onset of depression during adolescence may be indicative of problems of adaptation that persist at least a decade into early adulthood.

The association between antidepressant use and depression eight years later: a national cohort study.

Investigations of the effects of antidepressant treatment for individuals with major depression have focused on short-term outcomes in individuals that meet very specific criteria; however, there is limited knowledge about long-term outcomes associated with antidepressant use in general population samples. This study aimed to investigate the long-term outcomes associated with antidepressant use by focusing on 486 depressed adults in a prospective observational Canadian cohort in 1998/99. We used logistic regression to investigate the association between antidepressant use and depression status 8 years later. Non-random allocation to treatment was accounted for by a propensity-for-treatment model which included thirteen predictors of antidepressant use, including: severity of depressive symptoms, previous episodes of depression (from 1994 to 1997), physical health condition, social support and socio-demographic characteristics. 29% of individuals with major depression reported antidepressant use. After adjusting for propensity for treatment in 1998/99, and antidepressant use from 2000 to 2007, depressed individuals who reported antidepressant use in 1998/99 were less likely to be depressed in 2006/07 compared to those who did not report antidepressant use (OR = 0.36, 95% CI: 0.15-0.88). Amongst individuals with symptoms of major depression, those reporting use of anti-depressants at baseline exhibited improved long-term outcomes in comparison to those who did not report treatment.