Mej Wadsworth

Central and total obesity in middle aged men and women in relation to lifetime socioeconomic status: evidence from a national birth cohort

Study objective: To investigate the influence of social class in childhood, young adulthood and middle age, and intergenerational mobility, on adult central and total obesity. Design: Prospective, population based, birth cohort study. Participants and Setting: 1472 men and 1563 women born in 1946 in England, Scotland, and Wales. Outcome measures: Waist-hip ratio, waist-height ratio, waist circumference, and body mass index at age 53 years. Main results: Father’s social class at participant’s age 4 years was inversely associated with adult central and total obesity at age 53 years in men and women. For example, the mean difference of waist-hip ratio (95% confidence intervals) between father’s professional social class I and unskilled manual social class V was 2.6% (0.7 to 4.6) for men and 2.5% (0.5 to 4.4) for women. The effect of father’s social class remained after adjustment for participant’s own social class in young adulthood and middle age. Both adult social classes were inversely related to obesity among women, but not men, after adjustment for childhood circumstances. Upwardly mobile men and women were less obese than participants remaining in their father’s social class and their levels of obesity tended to be between the class they left and the class they joined. Conclusions: The effect of social class on adult obesity differed according to the stage in the life course at which social class was measured, and gender. Childhood circumstances had enduring influences on adult obesity, although our results on intergenerational mobility indicate potential reversibility of early life disadvantage.

Social and regional differences in food and alcohol consumption and their measurement in a national birth cohort.

The problem of collecting detailed dietary information on a large population scattered throughout England, Wales and Scotland was resolved by use of a 7 day dietary diary, introduced at home interviews. Information on food types and quantities was coded to provide data on a wide range of nutrients. Reported levels of iron and fibre intake were found to be particularly low in relation to current recommended daily intakes, which were more often achieved by men than by women. Best dietary habits were associated with good educational attainment, whatever the social class of origin, but in women this was in some circumstances associated also with relatively high intakes of alcohol, protein and fats. Worst dietary habits were associated with low social class of family of origin and low educational attainment. Mean intakes of some nutrients varied significantly by region, in most cases independently of class and education. The implications of these findings are discussed.

Long term effects of early adversity on cognitive function

Aims: To investigate long term effects of early adverse circumstances on cognitive function. Methods: Associations between early material home circumstances, parental divorce, maternal management and understanding, and cognitive function in childhood, adolescence, and adulthood were analysed using multiple linear regression, controlling for sex, parental SES, and birth order in 1339 males and females from the MRC National Survey of Health and Development. Results: Early adverse circumstances were strongly associated with lower cognitive ability in childhood and adolescence, and were detectable on measures of verbal ability, memory, and speed and concentration in midlife. However, these long term effects were mostly explained by the effects of adversity on childhood or adolescent cognitive ability or by differences in educational attainment and adult social class. An exception was the effect of poor material home conditions on visual search speed at 53 years, which was maintained after controlling for adolescent ability, as well as further control for educational attainment, adult social class, physical growth, cigarette smoking, and affective state. There was no evidence of more rapid decline in memory and psychomotor function across middle age in those exposed to early adversity. Conclusions: The effect of early adversity on cognitive function tracks across the life course at least as far as middle age, although there was little evidence from this study of effect amplification over this interval. Nevertheless, in view of the persistence of child poverty in the industrialised world, these findings give cause for concern.

CHRONIC PHYSICAL ILLNESS IN CHILDHOOD: PSYCHOLOGICAL AND SOCIAL EFFECTS IN ADOLESCENCE AND ADULT LIFE

A national birth cohort followed for 36 years was used to compare the life chances of individuals with chronic physical illness in childhood with those of controls. The majority of those who had been chronically physically ill in childhood were found to differ very little in social and psychological circumstances by 36 years of age, but earlier in adult life there had been signs of difficulties. However, there was a disturbing tendency for those from lower social‐group families to be in significantly worse social and psychological circumstances, and by 36 years they showed signs of relatively poor life chances and of basic social support, including the death of both parents.

The effects of divorce and separation on mental health in a national UK birth cohort.

BACKGROUND Many studies have reported a negative impact of divorce and separation on health although it is still unclear to what extent this is due to early vulnerability, the material and social consequences of divorce or to its direct emotional effects. METHOD Measures of anxiety and depression and potential alcohol abuse at age 43 were compared in 2085 participants from the MRC National Survey of Health and Development who were either married and never divorced or separated, or who had divorced or separated at least once. Analyses were adjusted for sociodemographic features, early vulnerability factors and current stressors. RESULTS Divorce and separation were associated with increased anxiety and depression, and increased risk of alcohol abuse. This was the case after adjusting for educational attainment, age at first marriage, parental divorce, childhood aggression and neuroticism, and current financial hardship, lack of a confidante and frequency of social contact with friends or family. The association between divorce and risk of alcohol abuse became non-significant when the latter variable was controlled for. Associations between divorce and psychopathology were observed even though half of those separated or divorced were re-married or reunited with their spouses at the time of the analysis. There was, furthermore, no association between these mental health measures and time since first separation or divorce.

The protective role of trait anxiety: a longitudinal cohort study

BACKGROUND Most research has indicated that neuroticism (or trait anxiety) is associated with only negative outcomes. Such a common, heritable and variable trait is expected to have beneficial as well as detrimental effects. We tested the hypothesis that trait anxiety in childhood reduces the risk of dying from accidental causes in early adult life. METHOD A longitudinal, population-based, birth cohort study of 4,070 men and women born in the UK in 1946. Trait anxiety as judged by teachers when the participants were 13 and 15 years old, and the neuroticism scale of a Maudsley Personality Inventory (MPI) when the participants were 16 years old. Outcomes were deaths, deaths from accidents, non-fatal accidents, and non-fatal accidents requiring medical intervention. RESULTS Adolescents with low trait anxiety had higher rates of accident mortality to age 25 [low anxiety at 13, hazard ratio (HR) 5.9, low anxiety at 15, HR 1.8]. Low trait anxiety in adolescence was associated with decreased non-accidental mortality after age 25 (low anxiety at 13, HR 0; low anxiety at 15, HR 0.7; low neuroticism at 16, HR 0.7). CONCLUSIONS High trait anxiety measured in adolescence is associated with reduced accidents and accidental death in early adulthood but higher rates of non-accidental mortality in later life.

The relationship between prior psychiatric disorder and chronic fatigue: evidence from a national birth cohort study

BACKGROUND Increased rates of psychiatric disorder have previously been reported in those diagnosed with chronic fatigue syndrome (CFS) or myalgic encephalomyelitis (ME), although the direction of causation in this relationship has not been established. We aimed to test the hypothesis that individuals with self-reported CFS/ME have increased levels of psychiatric disorder prior to the onset of their fatigue symptoms. METHOD A total of 5,362 participants were prospectively followed with various measures of personality, psychiatric disorder and fatigue levels collected over the first 43 years of their life. CFS/ME was identified through self-report during a semi-structured interview at age 53 years. RESULTS Thirty-four (1.1%) of the 3,035 subjects assessed at age 53 years reported a diagnosis of CFS/ME. CFS/ME was more common among females, but there was no association between CFS/ME and either social class, social mobility or educational level. Those with psychiatric illness between the ages of 15 and 36 years were more likely to report CFS/ME later in life with an odds ratio (OR, adjusted for sex) of 2.65 [95% confidence interval (CI) 1.26-5.57, p=0.01]. Increased levels of psychiatric illness, in particular depression and anxiety, were present prior to the occurrence of fatigue symptoms. There was a dose-response relationship between the severity of psychiatric symptoms and the likelihood of later CFS/ME. Personality factors were not associated with a self-reported diagnosis of CFS/ME. CONCLUSIONS This temporal, dose-response relationship suggests that psychiatric disorders, or shared risk factors for psychiatric disorders, are likely to have an aetiological role in some cases of CFS/ME.

Cardiovascular risk at age 53 years in relation to the menopause transition and use of hormone replacement therapy: a prospective British birth cohort study.

Objectives  To investigate cardiovascular risk factors and changes in risk factor levels in relation to menopausal stage, hysterectomy status and hormone replacement therapy use in a cohort of women aged 53 years with prospective data on smoking, lifetime socio‐economic circumstances, and blood pressure and obesity at age 43 years.

Early growth and type 2 diabetes: evidence from the 1946 British birth cohort

Aims/hypothesisWe assessed whether low birthweight or early adiposity rebound was more strongly associated with type 2 diabetes, and whether any effect of low birthweight or early adiposity rebound was explained by adult BMI, adult height, social class of subject or of his/her father, or maternal or paternal diabetes.MethodsCox’s proportional hazard models were used on data from the National Birth Cohort Study (the MRC National Survey of Health and Development), which was begun in 1946 and had self-reported physician-diagnosed diabetes with age at onset ranging from 31 to 53 years (n=78 cases, and n=47 cases in the multivariate analysis) as the outcome.ResultsA U-shaped association between birthweight and type 2 diabetes rates was close to statistical significance (quadratic term p value=0.08). Younger age at adiposity rebound was associated with increased rates of type 2 diabetes (test for trend p=0.002), the association being robust to adjustment for each of sex, birthweight, weight at 2 years, father’s social class, parental diabetes, and own social class. The effect of early adiposity rebound was very slightly reduced by adjustment for sex and adult height (p=0.003), but considerably reduced after adjustment for sex and adult BMI (test for trend p=0.1), and further reduced (p=0.4) after additional adjustment for birthweight, weight at 2 years, adult height, social class of subject and of his/her father, and parental diabetes.Conclusions/interpretationEarly adiposity rebound was associated with an increased rate of type 2 diabetes independently of birthweight, but its effect was mostly through high adult BMI. Parental diabetes and possibly low weight at 2 years were also risks.

Infant nutrition and cognitive development in the first offspring of a national UK birth cohort

Several studies show a modest beneficial effect of breastfeeding on cognitive development after controlling for sociodemographic confounders. It is still unclear, however, to what extent this is due to the nutritional advantage of breast milk or to environmental influences associated with breastfeeding. We compared verbal ability scores at age 8 years in 511 first‐born offspring of the National Survey of Health and Development who were ever or never breastfed, adjusting for paternal occupation, maternal education, maternal cognitive performance, attendance at nursery school, and maternal age at birth of the participant. A positive association between breastfeeding and cognitive performance was found but this was no longer the case after adjusting for either paternal occupation, maternal education, or maternal cognitive performance in turn. In contrast, an association between breastfeeding and cognitive function was not found for mothers of these offspring. Breastfeeding was increasingly associated with a non‐manual social class across the generations although it remains unclear how this might mediate the effect of breastfeeding on cognitive performance.