Occupational class and ischemic heart disease mortality in the United States and 11 European countries.

OBJECTIVES: Twelve countries were compared with respect to occupational class differences in ischemic heart disease mortality in order to identify factors that are associated with smaller or larger mortality differences. METHODS: Data on mortality by occupational class among men aged 30 to 64 years were obtained from national longitudinal or cross-sectional studies for the 1980s. A common occupational class scheme was applied to most countries. Potential effects of the main data problems were evaluated quantitatively. RESULTS: A north-south contrast existed within Europe. In England and Wales, Ireland, and Nordic countries, manual classes had higher mortality rates than nonmanual classes. In France, Switzerland, and Mediterranean countries, manual classes had mortality rates as low as, or lower than, those among nonmanual classes. Compared with Northern Europe, mortality differences in the United States were smaller (among men aged 30-44 years) or about as large (among men aged 45-64 years). CONCLUSIONS: The results underline the highly variable nature of socioeconomic inequalities in ischemic heart disease mortality. These inequalities appear to be highly sensitive to social gradients in behavioral risk factors. These risk factor gradients are determined by cultural as well as socioeconomic developments.

Trends in abortion 1990-1995.

Trends in legal abortion performed to women resident in England and Wales, between the years 1990 and 1995 are reviewed. This article updates an earlier review of abortion trends from the introduction of the 1967 Abortion Act to the end of 1989 which appeared in Population Trends issue no. 64(1). The main findings of this present article indicate that the number of legal abortions performed in England and Wales have gone down since 1990. Outside factors such as patterns in fertility, the provision and uptake of family planning services, and sexual attitudes and behaviour are likely to influence present and future trends. This article is part of an ongoing review of abortion trends which will be continued in future years.

PIP: This report covers trends in the incidence of and justification for legal abortion in England and Wales for the period 1990-95. The review is preceded by a description of the 1990 amendment of the 1967 Abortion Act reducing the time limit for legal abortion from 28 to 24 weeks gestation for two of the statutory grounds permitting abortion. The remaining five statutory grounds exist without time limits. The terms of the Act were also expanded to cover selective abortion in the case of a multiple pregnancy. The review opens with an overview of abortion trends for 1968-95 that indicates that the number of abortions performed for residents and nonresidents has dropped each year from 1991. Trends for 1990-95 among residents of England and Wales are discussed in terms of gestation period, statutory grounds, gestation period and statutory grounds, and statutory grounds and age of woman (for 1995). The review also categorizes legal terminations by procedure and notes that medical abortions have been available since 1991. After presenting data on abortions performed at more than 24 weeks gestation and selective terminations, the review considers legal terminations to nonresidents, overall conception patterns for 1969-94, age-specific conception patterns for 1990-94, and unplanned pregnancies and contraception patterns. Survey results on sexual attitudes and behavior and attitudes towards abortion are summarized, and it is concluded that a continuing trend towards earlier abortions exists and that trends will likely be affected by fertility patterns, access to family planning services and education, contraceptive practices, and sexual attitudes and behavior.

Occupation and ischemic heart disease in the European Community: a comparative study of occupations at potential high risk.

Four longitudinal studies of mortality and morbidity by occupation based on individual record linkage of information and two cross-sectional studies of mortality were compared in order to identify occupations at high risk of ischemic heart disease. In more than one country an increased risk of ischemic heart disease was found in drivers of buses, taxies, and lorries, in bakers, in naval officers and fishermen, in hotel and restaurant workers, in senior police, customs, and other uniformed men, in barbers and hairdressers, in warehouse and wholesale staff, as well as in laboratory assistants and in radio and telegraph operators. Occupations found at high risk in Denmark were also found at high risk in Great Britain and Italy. These occupations may be at genuine high risk. None of these groups work day-work only and several of the groups have psychologically demanding work but unsatisfactory decision authority. Identification of occupations at high risk may help to develop focused preventive strategies.

Differences in mortality by housing tenure and by car access from the OPCS Longitudinal Study.

Housing tenure and household access to a car are useful indicators of socio-economic status. They are simple to collect and process in censuses and surveys, and are effective discriminators of mortality. They can be used for all members of the population including children, women and the retired. These are groups where socio-economic differences in mortality based on occupation can be difficult to interpret. Using Longitudinal Study data, this article presents an analysis of differences in male and female mortality in England and Wales in the 1980s according to household tenure and car access. The findings are compared with those observed in the 1970s. Mortality levels are lower in the 1980s for all groups. The analyses suggest that differences across tenure and car access groups have increased in relative and absolute terms, particularly for those under 65.

Social patterning of medical mortality in youth and early adulthood.

It has been suggested that socio-economic gradients in health reduce or disappear during youth, to be re-created during early adulthood through a process of health-related social mobility. The present analysis tests this hypothesis in relation to 'medical mortality', using a data set which is free of numerator-denominator bias. The sample consists of the appropriate age groups in the OPCS Longitudinal Study; 62,647 males and 59,644 females aged 0-14 at the 1971 census. 'Medical mortality' during 1971-1985, calculated as standardised mortality ratios, is analysed by parental social class, housing tenure and car access in 1971. 'Medical mortality' during 1981-1985 is analysed by own social class in 1981. The results suggest that 'medical mortality' is inversely related to social advantage at ages of death 0-9 years, that this gradient flattens or disappears at ages 10-14 and that it re-emerges at ages 15-29. Within the present analysis this apparent re-emergence could not have been due to health-related social mobility. It is concluded that the apparent absence of socio-economic gradients in 'medical mortality' during youth may be an artefact of the high levels of health enjoyed by this age group and its consequent low levels of non-accidental death.

Intergenerational studies of human birthweight from the 1958 birth cohort. II. Do parents who were twins have babies as heavy as those born to singletons?

OBJECTIVE: To ascertain whether maternal twinning influences the previously described association between the birthweight of singleton mothers and their infants. DESIGN AND SUBJECTS: The association between the birthweight of singleton parents and their offspring and that between twin parents and their offspring was compared using data from the 23-year-old sample of the 1958 British national birth cohort. The numbers available for full comparison were 1027 female and 611 male singleton cohort members, and 26 female and 17 male twin cohort members and their first singleton livebirths. RESULTS: Of the mothers who had been twins, half had been of low birthweight, and overall their mean weight was 700 g less than that of their singleton counterparts. Nevertheless, the mean birthweight of babies of twin mothers was 133 g, and of twin fathers 94 g, greater than of babies of corresponding singletons. For female, but not male, parents this difference persisted after adjustment for confounding variables. CONCLUSIONS: We suggest two possible reasons for the difference between the weight of babies of twin and singleton mothers. Firstly, the growth of twins becomes retarded late in pregnancy, possibly after a period critical in determining long-term reproductive effects. Secondly, the twin survivors were of higher birthweight than the original twin cohort, whilst the singleton survivors were more representative of all singleton births, thus introducing a possible bias.

The contrasting effects of parental birthweight and gestational age on the birthweight of offspring.

Investigations on intergenerational effects on birthweight have been carried out using the data of the 1958 British National Birthday Trust Fund cohort and its follow-up to 23 years, the National Child Development Study (NCDS-4), which included information on all births to cohort members by that age. This report is directed particularly at ascertaining the independent effect of parental gestational age on babies' birthweight. The two main findings are a direct association between parental and offspring birthweight (significant for both mothers and fathers after allowing for confounding factors), but an inverse association with parental gestational age (significant only for the mothers). It is postulated that at least part of this effect is mediated through the association between maternal fetal growth rate and their babies' birthweight; the faster the rate the shorter the gestational age for a given birthweight. It was not possible to ascertain what part genetic factors played in this relationship. Larger and more informative intergenerational studies are needed to further knowledge on this question.

Intergenerational studies of human birthweight from the 1958 birth cohort. 1. Evidence for a multigenerational effect.

OBJECTIVE: To investigate possible multigenerational influences on birthweight. DESIGN: Data from the longitudinal study of one week's births in 1958 up to the age of 23 years, the British National Child Development Study, were utilized. These provide socio-biological information on the parents of the cohort, on the cohort members from birth onwards, and on the pregnancies and the birthweight of any babies born to the cohort members. MAIN OUTCOME MEASURE: The main outcome was the birthweight of babies born to the cohort members, for whom complete intergenerational data were available for 1638 firstborn. Multiple regression modelling was used to investigate any associations between their birthweight and characteristics of their parents and grandparents. RESULTS: Significant positive associations were found between babies' birthweight and parental birthweight but not gestational age. For the babies born to female cohort members additional findings included associations between their birthweight and the height of the maternal grandmother and the social class of the maternal grandfather, even after adjustment for such strong predictors of birthweight as maternal weight, smoking habit in pregnancy and baby's sex and birth order. CONCLUSION: These results thus offer support for a multigenerational influence on birthweight passed through the maternal line.

Early influences on the secular change in adult height between the parents and children of the 1958 birth cohort.

The present account is of data available from the 1958 British national birth cohort and its follow-up to the age of 23 years. It shows an increase in adult height between the cohort members and their parents, amounting to an average 1.2 +/- 0.11 (SEM) cm between the daughters and their mothers and 3.0 +/- 0.12 cm between the sons and their fathers. Factors in early life which contributed jointly to a significant increase in adult height included, as well as sex and parental height, birthweight and maternal pre-pregnant weight, while increasing gestational age had a negative effect. Overall these factors accounted for 71% of the variance of the cohort members' height. Measuring the intergenerational difference between individual pairs of sons and father and daughters and mothers allows to some extent for social and genetic influences. This showed that the size of the difference was increased by increasing intrauterine growth rate, and falling paternal social class. These findings demonstrate again the lifelong influence on offspring of circumstances pertaining at their birth and explain why it may take more than one generation to overcome the effects of childhood disadvantage.