Maria Melchior

Generalized anxiety disorder and depression : childhood risk factors in a birth cohort followed to age 32

BACKGROUND The close association between generalized anxiety disorder (GAD) and major depressive disorder (MDD) prompts questions about how to characterize them in future diagnostic systems. We tested whether risk factors for MDD and GAD are similar or different. METHOD The representative 1972-73 Dunedin birth cohort of 1037 males and females was followed to age 32 with 96% retention. Adult GAD and MDD were diagnosed at ages 18, 21, 26, and 32 years, and juvenile anxiety/depression were also taken into account. Thirteen prospective risk measures indexed domains of family history, adverse family environment, childhood behavior, and adolescent self-esteem and personality traits. RESULTS Co-morbid MDD+GAD was antedated by highly elevated risk factors broadly across all domains. MDD+GAD was further characterized by the earliest onset, most recurrence, and greatest use of mental health services and medication. Pure GAD had levels of risk factors similar to the elevated levels for co-morbid MDD+GAD; generally, pure MDD did not. Pure GAD had risks during childhood not shared by pure MDD, in domains of adverse family environment (low SES, somewhat more maltreatment) and childhood behavior (internalizing problems, conduct problems, somewhat more inhibited temperament). Pure MDD had risks not shared by pure GAD, in domains of family history (of depression) and personality (low positive emotionality). CONCLUSIONS Specific antecedent risk factors for pure adult MDD versus GAD may suggest partly different etiological pathways. That GAD and co-morbid MDD+GAD share many risk markers suggests that the presence of GAD may signal a pathway toward relatively more severe internalizing disorder.

Do psychosocial work factors and social relations exert independent effects on sickness absence? A six year prospective study of the GAZEL cohort

Study objectives: The objective of this prospective cohort study was to determine whether psychosocial work characteristics and social relations exert independent effects on the incidence of sickness absence in a population of middle aged French employees over six years of follow up. Design: This study included 9631 men and 3595 women participating in the French GAZEL cohort. Social relations (social networks, personal social support, and social relations satisfaction) were measured in 1994 by self report. Psychosocial work characteristics (decision latitude, psychological demands, and social support at work) were ascertained in 1995. Sickness absence data were collected independently. The authors studied the incidence of short (>7 days), intermediate (7–21 days), and long (>21 days) spells of absence from 1995 to 31 December 2001. Rate ratios associated with psychosocial exposures, adjusted on sociodemographic characteristics, and health behaviours, were calculated by means of log-linear Poisson regression. Setting: A cohort of 20000 employees of France’s national gas and electricity company (the GAZEL study). Main results: Among men and women, levels of decision latitude and personal social support below the median predicted 17% to 24% increases in absence rates. Low satisfaction with social relations and low social support at work lead to a 10% to 26% excess in sick leaves among men. No interactive effects were found between the variables under study. Conclusions: The quality of the work environment and of social relations affect sickness absence over an extended period of follow up. This study supports the hypothesis of independent, not interactive effects.

Self-rated health before and after retirement in France (GAZEL): a cohort study

BACKGROUND Governments need to increase the proportion of the population in work in most developed countries because of ageing populations. We investigated longitudinally how self-perceived health is affected by work and retirement in older workers. METHODS We examined trajectories of self-rated health in 14 714 employees (11 581 [79%] men) from the French national gas and electricity company, the GAZEL cohort, for up to 7 years before and 7 years after retirement, with yearly measurements from 1989 to 2007. We analysed data by use of repeated-measures logistic regression with generalised estimating equations. FINDINGS Overall, suboptimum health increased with age. However, between the year before retirement and the year after, the estimated prevalence of suboptimum health fell from 19.2% (95% CI 18.5-19.9) to 14.3% (13.7-14.9), corresponding to a gain in health of 8-10 years. We noted this retirement-related improvement in men (odds ratio 0.68, 95% CI 0.64-0.73) and women (0.74, 0.67-0.83), and across occupational grades (low 0.72, 0.63-0.82; high 0.70, 0.63-0.77), and it was maintained throughout the 7 years after retirement. A poor work environment and health complaints before retirement were associated with a steeper yearly increase in the prevalence of suboptimum health while still in work, and a greater retirement-related improvement; however, people with a combination of high occupational grade, low demands, and high satisfaction at work showed no such retirement-related improvement. INTERPRETATION These findings suggest that the burden of ill-health, in terms of perceived health problems, is substantially relieved by retirement for all groups of workers apart from those with ideal working conditions, and that working life for older workers needs to be redesigned to achieve higher labour-market participation. FUNDING Swedish Council for Working Life and Social Research, Academy of Finland, INSERM (France), BUPA Foundation (UK), European Science Foundation, and Economic and Social Research Council (UK).

Social relations and self-reported health: a prospective analysis of the French Gazel cohort.

Social networks and social support are strongly associated with health, yet the pathways between social relations and health are not well understood. In one of the very few studies on this issue conducted in France, we used data from the French GAZEL cohort of employees of the national gas and electricity company, to (1) explore the relationship between the structure and function of the social environment upon self-reported health and (2) test the hypothesis that social relations directly affect health. In a prospective analysis over a 12-month follow-up period, we found that a lack of social support and dissatisfaction with social relations are predictive of poor health status, while weak social networks are not. Thus, functional aspects of social relations are better predictors of poor health than the structure of social interactions. Low social support was an independent risk factor for poor health in men and women: for men the effect was strongest among individuals who held a high occupational status, for women among those in high and low occupational groups. This study suggests that in France social relations exert an independent effect on health, modified by gender and socio-economic factors. Our results indicate that both clinicians in their practice and researchers may do well to focus increased attention on the health impact of social support.

Early Risk Factors for Hyperactivity-Impulsivity and Inattention Trajectories From Age 17 Months to 8 Years

CONTEXT Attention-deficit/hyperactivity disorder is an etiologically heterogeneous neurodevelopmental condition with long-term negative outcomes. However, the early developmental course of hyperactivity-impulsivity and inattention symptoms and their association with previous environmental risk factors are still poorly understood OBJECTIVES To describe the developmental trajectories of hyperactivity-impulsivity and inattention symptoms and to identify their prenatal, perinatal, and postnatal risk factors. DESIGN Birth cohort from the general population. SETTING Quebec Longitudinal Study of Child Development. PARTICIPANTS The sample consisted of 2057 individuals, followed up from age 5 months to 8 years. MAIN OUTCOME MEASURES Prenatal, perinatal, and postnatal risk factors assessed at age 5 months were considered predictors of group membership in high hyperactivity-impulsivity and inattention trajectories from age 17 months to 8 years. RESULTS The frequency of hyperactivity-impulsivity symptoms tended to slightly decrease with age, whereas the frequency of inattention symptoms substantially increased up to age 6 years. However, trajectories of hyperactivity-impulsivity and inattention symptoms were significantly associated with each other. Risk factors for high trajectories of both types of symptoms were premature birth (adjusted odds ratio [aOR], 1.93; 95% CI, 1.07-3.50), low birth weight (2.11; 1.12-3.98), prenatal tobacco exposure (1.41; 1.03-1.93), nonintact family (1.85; 1.26-2.70), young maternal age at birth of the target child (1.78; 1.17-2.69), paternal history of antisocial behavior (1.78; 1.28-2.47), and maternal depression (1.35; 1.18-1.54). CONCLUSIONS A large range of early risk factors, including prenatal, perinatal social, and parental psychopathology variables, act independently to heighten the likelihood of having persistently high levels of hyperactivity-impulsivity and inattention symptoms from infancy to middle childhood. Early interventions should be experimented with to provide effective tools for attention-deficit/hyperactivity disorder prevention.

Effect of retirement on major chronic conditions and fatigue: French GAZEL occupational cohort study

Objectives To determine, using longitudinal analyses, if retirement is followed by a change in the risk of incident chronic diseases, depressive symptoms, and fatigue. Design Prospective study with repeat measures from 7 years before to 7 years after retirement. Setting Large French occupational cohort (the GAZEL study), 1989-2007. Participants 11 246 men and 2858 women. Main outcome measures Respiratory disease, diabetes, coronary heart disease and stroke, mental fatigue, and physical fatigue, measured annually by self report over the 15 year observation period; depressive symptoms measured at four time points. Results The average number of repeat measurements per participant was 12.1. Repeated measures logistic regression with generalised estimating equations showed that the cumulative prevalence of self reported respiratory disease, diabetes, and coronary heart disease and stroke increased with age, with no break in the trend around retirement. In contrast, retirement was associated with a substantial decrease in the prevalence of both mental fatigue (odds ratio for fatigue one year after versus one year before retirement 0.19, 95% confidence interval 0.18 to 0.21) and physical fatigue (0.27, 0.26 to 0.30). A major decrease was also observed in depressive symptoms (0.60, 0.53 to 0.67). The decrease in fatigue around retirement was more pronounced among people with a chronic disease before retirement. Conclusions Longitudinal modelling of repeat data showed that retirement did not change the risk of major chronic diseases but was associated with a substantial reduction in mental and physical fatigue and depressive symptoms, particularly among people with chronic diseases.

Tobacco, alcohol, cannabis and other illegal drug use among young adults: The socioeconomic context

BACKGROUND Low socioeconomic position predicts risk of substance abuse, yet few studies tested the role of preexisting familial and individual characteristics. METHODS Data come from the TEMPO (Trajectoires Epidémiologiques en Population) study (community sample in France, 1991-2009, n=1103, 22-35 years in 2009) set up among offspring of participants of an epidemiological study (GAZEL). Past 12-month substance use was assessed in 2009 by self-completed mail survey: regular tobacco smoking, alcohol abuse (AUDIT), cannabis use, problematic cannabis use (CAST), other illegal drug use. Socioeconomic position was defined by educational attainment, occupational grade, employment stability and unemployment. Covariates included demographics (age, sex, relationship status, parenthood), family background (parental income, parental tobacco smoking, parental alcohol use), and juvenile characteristics (psychological problems, academic difficulties) measured longitudinally. RESULTS 35.8% of study participants were regular smokers, 14.3% abused alcohol, 22.6% used cannabis (6.3% had problematic cannabis use) and 4.1% used other illegal drugs. Except for alcohol abuse, substance use rates were systematically higher in individuals with low, rather than intermediate/high, socioeconomic position (age and sex-adjusted ORs from 1.75 for cannabis use to 2.11 for tobacco smoking and 2.44 for problematic cannabis use). In multivariate analyses these socioeconomic disparities were decreased, but remained statistically significant (except for illegal drugs other than cannabis). CONCLUSIONS Tobacco smoking, alcohol, cannabis and polysubstance use are common behaviors among young adults, particularly those experiencing socioeconomic disadvantage. Interventions aiming to decrease substance abuse and reduce socioeconomic inequalities in this area should be implemented early in life.

Association between dietary patterns and depressive symptoms over time: a 10-year follow-up study of the GAZEL cohort.

Background Data on the association between dietary patterns and depression are scarce. The objective of this study was to examine the longitudinal association between dietary patterns and depressive symptoms assessed repeatedly over 10 years in the French occupational GAZEL cohort. Methods A total of 9,272 men and 3,132 women, aged 45–60 years in 1998, completed a 35-item Food Frequency Questionnaire (FFQ) at baseline. Dietary patterns were derived by Principal Component Analysis. Depressive symptoms were assessed by the Center for Epidemiologic Studies Depression scale (CES-D) in 1999, 2002, 2005 and 2008. The main outcome measure was the repeated measures of CES-D. Longitudinal analyses were performed with logistic regression based on generalized estimating equations. Principal Findings The highest quartile of low-fat, western, high snack and high fat-sweet diets in men and low-fat and high snack diets in women were associated with higher likelihood of depressive symptoms at the start of the follow-up compared to the lowest quartile (OR between 1.16 and 1.50). Conversely, the highest quartile of traditional diet (characterized by fish and fruit consumption) was associated with a lower likelihood of depressive symptoms in women compared to the lowest quartile, with OR = 0.63 [95%CI, 0.50 to 0.80], as the healthy pattern (characterized by vegetables consumption) with OR = 0.72 [95%CI, 0.63 to 0.83] and OR = 0.75 [95%CI, 0.61 to 0.93] in men and women, respectively. However, there was probably a reverse causality effect for the healthy pattern. Conclusion This longitudinal study shows that several dietary patterns are associated with depressive symptoms and these associations track over time.

Childhood and adolescent hyperactivity-inattention symptoms and academic achievement 8 years later: the GAZEL Youth study.

BACKGROUND Children with attention deficit/hyperactivity disorder (ADHD) are at risk of negative academic outcomes. However, relatively few studies in this area have been based on long-term longitudinal designs and community-based settings. This study examined the link between childhood hyperactivity-inattention symptoms (HI-s) and subsequent academic achievement in a community setting, controlling for other behavioural symptoms, socio-economic status (SES) and environmental factors at baseline. METHOD The sample consisted of 1264 subjects (aged 12 to 26 years at follow-up) recruited from the longitudinal GAZEL Youth study. Psychopathology, environmental variables and academic outcomes were measured through self-reports. Multivariate modelling was performed to evaluate the effects of childhood HI-s and other risk factors on academic achievement 8 years later. RESULTS HI-s independently predicted grade retention [adjusted odds ratio (OR) 3.58, 95% confidence interval (CI) 2.38-5.39], failure to graduate from secondary school (adjusted OR 2.41, 95% CI 1.43-4.05), obtaining a lower-level diploma (adjusted OR 3.00, 95% CI 1.84-4.89), and lower academic performance. These results remained significant even after accounting for school difficulties at baseline. Negative academic outcomes were also significantly associated with childhood symptoms of conduct disorder (CD), even after accounting for adjustment variables. CONCLUSIONS This longitudinal survey replicates, in a general population-based setting, the finding of a link between HI-s and negative academic outcomes.

Diagnosis-specific sickness absence and all-cause mortality in the GAZEL study

Background: This study aims to examine diagnosis-specific sickness absence as a risk marker for all-cause mortality. Methods: Prospective occupational cohort (the GAZEL study). Medically certified sickness absence spells >7 days for 15 diagnostic categories, 1990–1992, were examined in relation to all-cause mortality, January 1993–February 2007. The reference group for each diagnostic category was participants with no spell >7 days for that diagnosis. The participants were French public utility workers (5271 women and 13 964 men) aged 37–51 years in 1990, forming the GAZEL study. Over the follow-up period, there were 144 deaths in women and 758 in men. Results: 7875 employees (41.0%) had at least one spell of sickness absence >7 days over the 3-year period. The commonest diagnoses were mental disorders, musculoskeletal diseases, respiratory diseases and external causes in both sexes; genitourinary diseases in women, and digestive and circulatory diseases in men. Of these common diagnoses, mental disorders in women, hazard ratio (95% confidence intervals) 1.24 (1.1 to 1.4), and mental disorders 1.35 (1.3 to 1.5), digestive diseases 1.29 (1.1 to 1.6) and circulatory diseases 1.35 (1.2 to 1.6) in men were associated with mortality after adjustment for age, employment grade and sickness absence in all other diagnostic categories. Conclusions: Employees with medically certified absence spells of 1 week or more over a 3-year period had a 60% excess risk of early death. In women and men this excess risk was associated with some of the commonest diagnoses of sickness absence, in particular mental disorders. Sickness absence for mental disorders may be a useful early indicator of groups at increased risk of fatal disease.