Claudia Thomas

Objectives: To examine the relationships between exposure to workplace factors (night work, extended working hours, psychosocial work stress) and cortisol secretion, and to test whether workplace factors interact, resulting in combined effects. Methods: Multiple linear and logistic regression was used to test relationships between workplace factors and cortisol secretion in the 1958 British birth cohort at 45 years. Salivary cortisol was measured twice on the same day to capture the post-waking decline, facilitating the analysis of different cortisol patterns: (1) time 1 (T1, 45 minutes post-waking); (2) time 2 (T2, 3 h after T1); (3) average 3 h exposure from T1 to T2 cortisol; and (4) T1 to T2 change. To identify altered diurnal cortisol patterns we calculated: (1) flat T1–T2 change in cortisol; (2) top 5% T1; (3) bottom 5% T1; and (4) T1 hypo-secretion or hyper-secretion. Models were adjusted for socioeconomic position at birth and in adulthood, qualifications, marital status, dependent children, and smoking status. Results: 25% of men and 8% of women were exposed to >1 workplace factor (night work, extended work hours, job strain). Night work was associated with a 4.28% (95% CI 1.21 to 7.45) increase in average 3 h cortisol secretion independently of job strain or work hours. Night workers not exposed to job strain had elevated T1 cortisol (5.81%, 95% CI 1.61 to 10.19), although for T2 cortisol it was night workers exposed to low job control who had elevated levels (11.72%, 95% CI 4.40 to 19.55). Men (but not women) working >48 h/week had lower average 3 h cortisol secretion (4.55%, 95% CI −8.43 to −0.50). There were no main effects for psychosocial work stress. All associations for T2 and average 3 h cortisol secretion weakened slightly after adjustment for confounding factors, but associations for T1 cortisol were unaffected by adjustment. Conclusions: Our study suggests that night work in particular is associated with elevated cortisol secretion and that cortisol dysregulation may exist in subgroups with specific combinations of stressors.

OBJECTIVE. Child abuse has been associated with poorer physical health in adulthood, but less is known about childhood adversity more broadly, including neglect and family problems, or the pathways from adversity to adult disease. We have examined how different stressful emotional or neglectful childhood adversities are related to adiposity and glucose control in midadulthood, taking into account childhood factors, and whether the relationships are mediated by adult health behaviors and socioeconomic position.METHODS. This was a prospective longitudinal study of 9310 members of the 1958 British birth cohort who participated in a biomedical interview at 45 years of age. Primary outcomes consisted of continuous measures of BMI, waist circumference, and glycosylated hemoglobin at 45 years and categorical indicators: total obesity (BMI ≥ 30), central obesity (waist circumference: ≥102 cm for men and ≥88 cm for women), and glycosylated hemoglobin level of ≥6.RESULTS. The risk of obesity increased by 20% to 50% for several adversities (physical abuse, verbal abuse, witnessed abuse, humiliation, neglect, strict upbringing, physical punishment, conflict or tension, low parental aspirations or interest in education, hardly takes outings with parents, and father hardly reads to child). Adversities with the strongest associations with adiposity (eg, physical abuse) tended to be associated with glycosylated hemoglobin levels of ≥6, but in most cases associations were explained by adjustment for adulthood mediators such as adiposity. Effects of other adversities reflecting less severe emotional neglect and family environment were largely explained by childhood socioeconomic factors.CONCLUSIONS. Some childhood adversities increase the risk of obesity in adulthood and thereby increase the risk for type 2 diabetes. Research is needed to understand the interrelatedness of adversities, the social context of their occurrence, and trajectories from adversity to adult disease.

OBJECTIVE—Birth weight has been associated with the risk of type 2 diabetes in several studies. We investigated whether prenatal influences on birth weight (gestational age, parity, preeclampsia, prepregnancy BMI, smoking during pregnancy, and socioeconomic position [SEP]) were associated with glucose metabolism in midlife and the role of birth weight for gestational age (BGA) and adult adiposity in mediating these associations.

Aims  Information on the population at risk of developing Type 2 diabetes in the UK is scarce. We used data from the 1958 British birth cohort to estimate geographical and socio‐economic variations in HbA_1c in mid life.Methods  Participants (n = 7799) born in England, Scotland and Wales and currently living in the UK. Individuals were classified according to the presence of Type 2 diabetes and by thresholds of HbA_1c. HbA_1c≥ 5.5 was used as an indicator for possible subclinical alterations in glucose metabolism.Results  The majority of the population had HbA_1c < 5.5% (79.3%); 16.7% had HbA_1c 5.5–5.9%, 2.0% 6.0–6.9% and 0.6% had HbA_1c≥ 7.0%. Individuals from manual socio‐economic groups and those living in the East of England and Scotland had a higher prevalence of HbA_1c at or above the upper normal range (5.5%).Conclusions  Estimates from this nationwide sample suggest that a proportion of Britons are likely to have subclinical alterations in glucose metabolism by their mid 40s, and this proportion is greater in some socio‐economic groups and geographical regions than in others.

Objective: To explore the extent to which the mental health effects of transitions into unemployment, or other forms of non-employment, and vice versa, are mediated by financial changes. Methods: Longitudinal analysis of the British Household Panel Survey from 1991 to 2000. There were 89 264 person-years of observation from 14 686 individuals aged ⩾16 years. Main outcome measure was psychological distress measured by the 12-item General Health Questionnaire. Results: Transitions to unemployment were associated with increased risk of psychological distress for men (adjusted odds ratio (OR) 3.15 (95% confidence interval (CI) 2.50 to 3.98)) and for women (OR 2.60 (95% CI 1.97 to 3.43)). Women who left work to look after the family were also more likely to experience psychological distress (OR 1.72 (95% CI 1.45 to 2.05)). A reduced risk of psychological distress was seen for transitions from unemployment to paid employment for men (OR 0.52 (95% CI 0.41 to 0.68)) and for women (OR 0.68 (95% CI 0.69 to 1.40)). Financial difficulty partially mediated these relationships: men who became unemployed and were worse off financially were more likely to experience psychological distress (OR 4.19 (95% CI 3.20 to 5.50)) than men who were not (OR 1.48 (95% CI 0.95 to 2.33)). Conversely, the beneficial health effect for people who left unemployment and became employed was confined to those who were better off financially (OR 0.34 (0.25 to 0.48) for men). Conclusions: Changes in employment status have both direct and indirect effects, through changes in financial circumstances, on subsequent psychological distress. The results support the view that the direction of causation runs from employment transitions to financial difficulties and psychological distress.

Type 2 diabetes mellitus is increasingly common and is predicted to continue to increase nationally and internationally.¹ Average life expectancy is reduced by as much as 10 years in people with type 2 diabetes, and there is a considerable health burden related to microvascular and macrovascular complications.² Approximately 15% to 20% of individuals with newly diagnosed diabetes present with retinopathy, and 5% to 10% have proteinuria.³ Disease onset can occur as early as 12 years before diabetes is diagnosed, because hyperglycemia develops gradually, with symptoms appearing later, and thus approximately half of all cases are undiagnosed.⁴ Although it is argued that there is no justification for general population screening,⁵ early detection of individuals at risk of diabetes could be beneficial because early intervention has the potential to prevent the development of diabetes and its complications.

Study objective: To describe the impact of changes between employment and various forms of non-employment, and vice versa, on the psychological wellbeing of men and of women. Design: Separate multivariate models for men and for women were constructed to study the association between employment transitions and episodes of psychological distress (general health questionnaire). Participants: 13 359 employment transitions from 5092 people aged 16–74 years in the British household panel survey from 1991 to 1998. Main results: Transitions from paid employment to either unemployment or long term sick leave were associated with increased psychological distress for both men and women. Starting maternity leave or staying home to look after the family were also associated with psychological distress for women. Transitions from these roles to formal employment resulted in an improvement in mental health. There was some evidence that the effects were felt most strongly within six months of the transition. Conclusions: This paper provides further evidence that movements between paid employment and various forms of non-employment, in addition to unemployment, have an impact on mental health. The emphasis on transitions between a full range of employment states for both men and women from a large population based longitudinal study and a comparison of the relative magnitude of effects are unique features of this analysis. Interventions are suggested to minimise the psychological distress associated with transitions.