The association of early IQ and education with mortality: 65 year longitudinal study in Malmö, Sweden.

OBJECTIVES: To establish whether differences in early IQ explain why people with longer education live longer, or whether differences in father's or own educational attainment explain why people with higher early IQ live longer. DESIGN: Population based longitudinal study. Mortality risks were estimated with Cox proportional hazards regressions. SETTING: Malmö, Sweden. PARTICIPANTS: 1530 children who took IQ tests at age 10 and were followed up until age 75. RESULTS: Own educational attainment was negatively associated with all cause mortality in both sexes, even when early IQ and father's education were adjusted for (hazard ratio (HR) for each additional year in school 0.91 (95% CI 0.85 to 0.97) for men and HR 0.88 (95 % CI 0.78 to 0.98) for women). Higher early IQ was linked with a reduced mortality risk in men, even when own educational attainment and father's education were adjusted for (HR for one standard deviation increase in IQ 0.85 (95 % CI 0.75 to 0.96)). In contrast, there was no crude effect of early IQ for women, and women with above average IQ had an increased mortality risk when own educational attainment was adjusted for, but only after the age of 60 (HR 1.60 (95 % CI 1.06 to 2.42)). Adding measures of social career over and above educational attainment to the model (for example, occupational status at age 36 and number of children) only marginally affected the hazard ratio for women with above average IQ (<5%). CONCLUSIONS: Mortality differences by own educational attainment were not explained by early IQ. Childhood IQ was independently linked, albeit differently, to male adult mortality and to female adult mortality even when father's education and own educational attainment was adjusted for, thus social background and own social career seem unlikely to be responsible for mortality differences by childhood IQ. The clear difference in the effect of IQ between men and women suggests that the link between IQ and mortality involves the social and physical environment rather than simply being a marker of a healthy body to begin with. Cognitive skills should, therefore, be addressed in our efforts to create childhood environments that promote health.

Golf: a game of life and death--reduced mortality in Swedish golf players.

The specific health benefits achieved from different forms and patterns of leisure-time physical activity are not established. We analyzed the mortality in a cohort of Swedish golf players. We used the Swedish Golf Federation's membership registry and the nationwide Mortality Registry. We calculated standardized mortality ratios (SMR) with stratification for age, sex, and socioeconomic status. The cohort included 300 818 golfers, and the total number of deaths was 1053. The overall SMR was 0.60 [95% confidence intervals (CIs): 0.57-0.64]. The mortality reduction was observed in men and women, in all age groups, and in all socioeconomic categories. Golfers with the lowest handicap (the most skilled players) had the lowest mortality; SMR=0.53 (95% CI: 0.41-0.67) compared with 0.68 (95% CI: 0.61-0.75) for those with the highest handicap. While we cannot conclude with certainty that all the 40% decreased mortality rates are explained by the physical activity associated with playing golf, we conclude that most likely this is part of the explanation. To put the observed mortality reduction in context, it may be noted that a 40% reduction of mortality rates corresponds to an increase in life expectancy of about 5 years.

Cost containment, solidarity and cautious experimentation: Swedish dilemmas.

This paper uses secondary data analysis and a literature review to explore a "Swedish Dilemma": Can Sweden continue to provide a high level of comprehensive health services for all regardless of ability to pay--a policy emphasizing "solidarity"--or must it decide to impose increasing constraints on health services spending and service delivery--a policy emphasizing "cost containment?" It examines recent policies and longer term trends including: changes in health personnel and facilities; integration of health and social services for older persons; introduction of competition among providers; cost sharing for patients; dismantling of dental insurance; decentralization of government responsibility; priority settings for treatment; and encouragement of the private sector. It is apparent that the Swedes have had considerable success in attaining cost containment--not primarily through "market mechanisms" but through government budget controls and service reduction. Further, it appears that equal access to care, or solidarity, may be adversely affected by some of the system changes.

Social determinants of birthweight, ponderal index and gestational age in Sweden in the 1920s and the 1980s.

This study compared the effect of social class and marital status on birth outcomes in Sweden, using (i) data on all births at the Akademiska Hospital in Uppsala from 1920 to 1924 with socioeconomic information from records at birth; and (ii) a linkage of the Medical Births Registry for all births in Sweden in November/December 1985 to the 1985 Census. Preterm births (<37 weeks) have become less common during the 20th century. Between 1920-24 and 1985, mean and median birthweight increased, as did mean ponderal index, indicating a shift to the right of the birthweight and ponderal index distributions. In 1920-24, birthweight and ponderal index were associated with the social class of the household and with the marital status of the mother. Babies of single mothers were lighter and thinner, and had a much greater probability of being born preterm. In contrast, in 1985, maternal marital status (and cohabitation status) had a weaker effect on birthweight and ponderal index. The importance of household social class for ponderal index and preterm birth changed similarly, but its importance for birthweight remained. The mediating mechanism may have changed. Mothers from farming households now gave birth to the heaviest babies (nearly 200 g heavier than those of unskilled workers). Adjustment for a number of factors, including smoking, had a limited effect on these social class differences. In conclusion, biological processes during the foetal period are systematically linked to the social circumstances of the mother, but in a different way in the 1920s and in 1985.

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.

Reduced fetal growth rate and increased risk of death from ischaemic heart disease: cohort study of 15 000 Swedish men and women born 1915-29.

OBJECTIVE: To establish whether fetal growth rate (as distinct from size at birth) is associated with mortality from ischaemic heart disease. DESIGN: Cohort study based on uniquely detailed obstetric records with 97% follow up over the entire life course and linkage to census data in adult life. SUBJECTS: All 14 611 babies delivered at the Uppsala Academic Hospital, Sweden, during 1915-29 followed up to end of 1995. MAIN OUTCOME MEASURES: Mortality from ischaemic heart disease and other causes. RESULTS: Cardiovascular disease showed an inverse association with birth weight for both men and women, although this was significant only for men. In men a 1000 g increase in birth weight was associated with a proportional reduction in the rate of ischaemic heart disease of 0.77 (95% confidence interval 0.67 to 0.90). Adjustment for socioeconomic circumstances at birth and in adult life led to slight attenuation of this effect. Relative to the lowest fourth of birth weight for gestational age, mortality from ischaemic heart disease in men in the second, third, and fourth fourths was 0.81 (0.66 to 0.98), 0.63 (0.50 to 0.78), and 0.67 (0.54 to 0.82), respectively. The inclusion of birth weight per se and birth weight for gestational age in the same model strengthened the association with birth weight for gestational age but removed the association with birth weight. CONCLUSION: This study provides by far the most persuasive evidence of a real association between size at birth and mortality from ischaemic heart disease in men, which cannot be explained by methodological artefact or socioeconomic confounding. It strongly suggests that it is variation in fetal growth rate rather than size at birth that is aetiologically important.

Social variation in size at birth and preterm delivery in the Czech Republic and Sweden, 1989-91.

All livebirths resulting from singleton pregnancies reported to the Czech (n = 380,633) and Swedish (n = 351,775) birth registries in 1989-91 were studied with respect to social variation in birthweight, ponderal index (weight/length at birth3) and preterm delivery. The mean birthweight was significantly lower in the Czech population (3310 g vs. 3522 g, P < 0.001). The mean difference in birthweight between children of mothers with primary and university education was 197 g [95% CI 190, 205] in the Czech and 136 g [95% CI 128, 144] in the Swedish population, adjusted for maternal age, parity and sex of the infant. Mean birthweight was significantly higher in mothers who were married or lived with partners in both countries; the difference was 167 g [95% CI 161, 173] in the Czech Republic (CR) and 86 g [95% CI 78, 94] in Sweden, adjusted for age, parity and sex. The extent of social variation in ponderal index and frequency of preterm birth was also greater in the CR. Between 1989 and 1991, mean birthweight in the CR fell from 3323 g to 3292 g (P < 0.001) and the social differences increased, largely as a result of more rapid worsening in the lower socio-economic groups. There did not appear to be such a decline in birthweight in Sweden. We suggest that the fall in mean birthweight and the increasing social variation in birth outcome in the CR is related to decline and divergence in living standards in 1989-91.

Socio-economic inequalities in mortality. Methodological problems illustrated with three examples from Europe.

BACKGROUND: Studies from most European countries have been able to demonstrate that lower socioeconomic groups have higher risks of disease, disability and premature death. Uncertain is, however, whether these studies have also been able to estimate the precise magnitude of these inequalities, their patterns and their trends over time. The purpose of this paper is to illustrate the extent to which results of descriptive studies can be biased due to problems with the data that are commonly available to European countries. METHODS: Three illustrations are presented from a project on socio-economic inequalities in premature morbidity and mortality in Europe. These illustrations concern three problems often encountered in data on social class differences in mortality among middle aged men: the numerator/denominator bias in cross-sectional studies (illustrated for France), the exclusion of economically inactive men (illustrated for 4 countries), and the use of approximate social class schemes (illustrated for Sweden). RESULTS: In each illustration, inequalities in mortality among middle aged men could be demonstrated, but data problems appeared to bias estimates of the precise magnitude of inequalities in mortality, their patterns by social class and cause of death, and their trends over time. The bias was substantial in most cases. Usually, it was difficult to predict in which ways and to what extent inequality estimates would have been biased. CONCLUSIONS: When the aim of a study is to determine the precise magnitude, patterns or time trends of health inequalities, the results should be evaluated carefully against a number of potential data problems. Investments are needed, e.g. in data sources and in the measurement of socio-economic status, to secure that future studies can describe socio-economic inequalities in health in Europe in more detail and with more reliability.

Can confounding by sociodemographic and behavioural factors explain the association between size at birth and blood pressure at age 50 in Sweden?

STUDY OBJECTIVE: To evaluate whether socioeconomic confounding explains the relationship between size at birth and blood pressure at age 50. DESIGN: Cross sectional study with retrospectively collected data on size at birth. SETTING: Uppsala, Sweden. PARTICIPANTS: 1333 men born in 1920-24, and a subset of 615 men for analyses including early social circumstances. MAIN OUTCOME MEASURES: Blood pressure measured after 10 minutes rest in supine position. Crude and adjusted effect measures were compared. MAIN RESULTS: Controlling for sociodemographic characteristics at age 50, such as socioeconomic position, highest education achieved and marital status did not reduce the strength of the association between birth weight and systolic blood pressure at 50 years. In the total population, the slope of the body mass index adjusted relationship changed from -3.4 mmHg/kg to -3.5 mmHg/kg on additional adjustment for sociodemographic characteristics at age 50 (both p values < 0.01). Controlling for behavioural characteristics at age 50, such as smoking and recent alcohol drinking, did not affect the relationship between birth weight and blood pressure at 50. In the 615 men for whom information on sociodemographic circumstances in early life was available, adjustment for factors such as social class of the family, mother's marital status or area of residence, led to a slight reduction of the effect of birth weight on systolic blood pressure at age 50. The slope of the body mass index adjusted relationship changed from -2.8 mmHg/kg to -2.6 mmHg/kg after additional adjustment for early life circumstances in the sample as a whole (p values 0.09 and 0.12). Simultaneous adjustment for sociodemographic characteristics at birth together with sociodemographic and behavioural characteristics at age 50 led to only a slight reduction of the effect of birth weight on systolic blood pressure at 50 years. CONCLUSION: The strong inverse associations between birth weight and blood pressure among 50 year old Swedish men are highly unlikely to be explained by confounding with socioeconomic circumstances at birth or in adult life.

Failure to realise growth potential in utero and adult obesity in relation to blood pressure in 50 year old Swedish men.

OBJECTIVES: To clarify the type of fetal growth impairment associated with increased blood pressure in adult life, and to establish whether this association is influenced by obesity and is mediated through impairment of insulin action. DESIGN: Cross sectional survey with retrospective ascertainment of size at birth from obstetric archives. SUBJECTS: 1333 men resident in Uppsala, Sweden, who took part in a 1970 study of coronary risk factors at age 50 and for whom birth weight was traced. MAIN OUTCOME MEASURES: Systolic and diastolic blood pressure at age 50. RESULTS: In the full study population for a 1000g increase in birth weight there was a small change in systolic blood pressure of -2.2mmHg (95% confidence interval -4.2 to - 0.3mmHg) and in diastolic blood pressure of -1.0mmHg (-2.2 to 0.1mmHg). Much stronger effects were observed among men who were born at term and were in the top third of body mass index at age 50, for whom a 1000g increase in birth weight was associated with a change of -9.1mmHg (-16.4 to-1.9mmHg) systolic and -4.2mmHg (-8.3 to -0.1mmHg) diastolic blood pressure. Men who were light at birth (<3250g) but were above median adult height had particularly high blood pressure. Adjustment for insulin concentrations reduced the associations of birth weight with systolic and diastolic blood pressure. CONCLUSIONS: A failure to realise growth potential in utero (as indicated by being light at birth but tall as an adult) is associated with raised adult blood pressure. Impaired fetal growth may lead to substantial increases in adult blood pressure among only those who become obese. Metabolic disturbances, possibly related to insulin resistance, may provide a pathway through which fetal growth affects blood pressure.

Equity and efficiency in health reform. A European view.

Health care reform in both eastern and western Europe is on the agenda, and in both parts of Europe the importance of equity targets has been questioned. In the East, the previously strongly held equity goals were largely a facade, covering all sorts of privilege systems, something which has brought equity as a concept into disrepute. However, present developments mean that it is quite likely to be back on the agenda again soon. In the West, equity has been seen as inevitably linked to non-market systems of health care. In moving towards market solutions equity has come to be seen as conflicting with efficiency goals. This contra-positioning of equity and efficiency does not stand up to critical examination. It is based on confusing strategic goals with the implementation of those goals. Equity could be seen as a strategic goal in its own right. We may ask what are the most efficient ways of financing, managing and delivering medical services to achieve that goal. Clearly this has not been the question on the agenda. Cost containment has been imperative, and the consequences for general health, equity in health or the health and care for those suffering most, has been relegated to second place. The reduction of inequalities in health can be seen as an overall strategy for the improvement of a population's health, and as helpful in the maintaining and improvement of its human capital.(ABSTRACT TRUNCATED AT 250 WORDS)

Ischaemic heart disease and low birth weight: a test of the fetal-origins hypothesis from the Swedish Twin Registry.

Twins constitute a population with lower than average birth weight for reasons that are not a consequence of social disadvantage. The hypothesis that ischaemic heart disease (IHD) is linked to low birth weight was tested by analysing whether or not 8174 female and 6612 male Swedish twins had a higher mortality compared to the general Swedish population. The association between adult body height and IHD mortality was also analysed in a nested case-control study among monozygotic and dizygotic twins. Ischaemic heart disease mortality was not higher among twins (women: relative risk [RR] 0.99; 95% confidence limits [CL] 0.89-1.10; men: RR 0.85; CL 0.79-0.92). However, the shorter twin in a twin pair was more likely to die of heart disease than the taller (odds ratio [OR] 1.15, CL 1.03-1.25). We suggest that postnatal influences may well be as important as prenatal influences in producing any effect on ischaemic heart disease mortality and that the type of growth retardation in utero experienced by twins may not constitute a risk for ischaemic heart disease in adulthood.

[Not only the orienteers. A study of mortality from myocarditis among the younger Swedish population]. / Inte bara orienterare. En studie av dödligheten i myokardit hos den yngre svenska befolkningen.

All cases of death in the 11-45-year-old age group, occurring during the period 1981-1986, where myocarditis was given as the underlying or contributory cause, were analysed. Estimated per 100,000 person years, mortality was 0.5 for men and 0.2 for women. There was a tendency toward geographic clustering and, independently, a clustering in time. Some variation according to socio-economic class was also present. We conclude that the current focus of Swedish research on myocarditis among orienteers is too narrow, as more than 90 percent of cases occur outside this group.

Today or in the past? The origins of ischaemic heart disease.

Recent studies have suggested that regional differences in death rates from ischaemic heart disease (IHD) may result from exposure to poverty in foetal and early infant life. The suggestion is that such influences 'permanently set structures and metabolic processes, so-called programming'. On this theory, current falls in IHD death rates reflect much earlier reductions in poverty. If the theory were correct, the fall in rates would begin with younger age groups and be reinforced only at the pace at which each new birth cohort reached adult life. There is no evidence of such a cohort effect. Rates fell simultaneously over a very brief period in each country and region examined. The results are more compatible with theories involving contemporary lifestyle changes.

Social class differences in infant mortality in Sweden: comparison with England and Wales.

OBJECTIVES: To investigate social class differences in infant mortality in Sweden in the mid-1980s and to compare their magnitude with that of those found in England and Wales. DESIGN: Analysis of risk of infant death by social class in aggregated routine data for the mid-1980s, which included the linkage of Swedish births to the 1985 census. SETTING: Sweden and England and Wales. SUBJECTS: All live births in Sweden (1985-6) and England and Wales (1983-5) and corresponding infant deaths were analysed. The Swedish data were coded to the British registrar general's social class schema. MAIN OUTCOME MEASURES: Risk of death in the neonatal and postneonatal period. RESULTS: Taking the non-manual classes as the reference group, in the neonatal period in Sweden the manual social classes had a relative risk for mortality of 1.20 (95% confidence interval 1.02 to 1.43) and those not classified into a social class a relative risk of 1.08 (0.88 to 1.33). In the postneonatal period the equivalent relative risks were 1.38 (1.08 to 1.77) for manual classes and 2.14 (1.65 to 2.79) for the residual; these are similar to those for England and Wales (1.43 (1.36 to 1.51) for manual classes, 2.62 (2.45 to 2.81) for the residual). CONCLUSIONS: The existence of an equitable health care system and a strong social welfare policy in Sweden has not eliminated inequalities in post-neonatal mortality. Furthermore, the very low risk of infant death in the Swedish non-manual group (4.8/1000 live births) represents a target towards which public health interventions should aim. If this rate prevailed in England and Wales, 63% of postneonatal deaths would be avoided.