No abstract

Exposure to tobacco during pregnancy is an important risk factor for infant health. Recently the prevalence of smoking during pregnancy has declined in our area. The objective of this study was to analyse the association between several social variables and the fetal exposure to smoking, as well as the association between maternal smoking and some adverse gestational outcomes. Data collection was cross-sectional. The study population were women in the city of Barcelona (Catalonia, Spain) delivering a child without birth defects. The sample corresponded to the controls of the Birth Defects Registry of Barcelona, 2% of all pregnancy deliveries in the city from 1994 to 2003 (n = 2297). Information sources were hospital records and a personal interview of mothers. The analysis measured first the association between independent variables (instruction level, social class, occupation, nationality, planned pregnancy, parity, hospital funding and smoking status of the mother's partner) with two dependent variables: smoking at the initiation of pregnancy and quitting during pregnancy. Second, the persistence of smoking over pregnancy and all independent variables were studied with three variables indicating adverse outcomes of pregnancy: low gestation, low birthweight and intrauterine growth restriction (IUGR). Finally, the joint association between the persistence of smoking over pregnancy and social class taken as independent variables was determined with the three variables indicating adverse outcomes of pregnancy. Logistic regression models were fitted, adjusting for maternal age. Results are presented as odds ratios with their 95% confidence intervals. The prevalence of smoking at the onset of gestation was 41%, and 40% of these women quit during pregnancy, so that 25% delivered as active smokers. Fewer women with higher educational levels and from families with non-manual jobs smoked, as did immigrants, those planning pregnancy and women whose partner did not smoke. Smoking immigrants quit more frequently than nationals, as did those planning pregnancy, primiparae, and women whose partner did not smoke. Low gestation, low birthweight and IUGR were more frequent among smokers and women with a manual occupation, but manual occupation lost its significance when adjusting for smoking. The association between smoking and adverse results was higher for IUGR. In conclusion, the prevalence of smoking and quitting during pregnancy varied according to social factors. The influence of social factors on the outcome of pregnancy was mediated strongly by smoking in a country that provides access to health care free of cost. A priority in reducing inequalities in health is to help women from manual work backgrounds quit smoking.

ABSTRACT. The study of socio-economic inequalities from a cross-national perspective has been hampered by the lack of adequate common indices of socioeconomic status that can be used in a self-report survey instrument. This paper examines the construction and the properties of global social indexes in general, and of the Family Affluence Scale (henceforth FAS) in particular. The paper proposes a new strategy for making comparisons of the global index with stratified data, building a revised FAS based on Adapted Canonical Variate Analysis (henceforth ACVA). This alternative strategy for constructing a global index is available in standard software, and the new proposal for stratified data only requires a simple program, which is justified, explained and provided in the text. Data come from the 1998 Health Behaviour in School-Aged Children (HBSC), a WHO Cross-National Study using cluster sampling of schoolchildren from five countries: Denmark, Latvia, Portugal, Scotland and the USA. The results reveal that in every country we would have had a completely different evaluation of the three indicators of Family Affluence if we had used either linear or non linear approaches to compute the global indexes. Moreover, Family Affluence comparisons among countries shows that the relative contribution of the three indicators to the overall FAS, changes from country to country. We conclude that separate indicators of Family Affluence are not equally relevant in each country and, as a consequence, do not contribute equally to the global index. For cross-cultural studies, the strategy for constructing an index should be country specific. The methodological developments presented in the paper open up opportunities to study socio-economic patterning of health among young people in the developed world, since self completed surveys can now employ a common measure of family material wealth. The findings show that the RFAS (Revised FAS) is a useful index of socio-economic status for use in national and cross-national surveys of adolescent health and health behaviour. The new strategy for weighting observed indicators in the index gives it enhanced power to detect inequalities.

We analysed the prevalence of cigarette smoking among subsequent birth cohorts of Spanish males and females. Data were drawn from the Spanish NHIS conducted in 1993 ( = 26 400), 1995 ( = 8300) and 1997 ( = 8300). From the original computer files, the three surveys were pooled to obtain a single sample. A total of 33 223 subjects (16 036 men and 17 187 women) born between 1900 and 1979, >/= 16 years old, were directly interviewed and with complete information on the history of smoking included for analysis. Based on each respondent's sex and calendar year of birth, the person was classified into a particular sex-birth cohort in the decades from 1900-09 to 1970-79. For each year from date of birth to date of survey, respondents were further classified as either cigarette smoker or nonsmoker. The prevalence of cigarette smoking among successive cohorts of Spanish men and women was estimated, with correction for excess mortality of smokers. In men, the peak in smoking was reached in the 1950-59 birth cohort (prevalence rate of 68% at ages 20-29), after increases during the previous calendar years. Smoking among women was rare until 1960. Female smoking prevalence rates increased progressively among subsequent cohorts until 1980. The age distribution of smoking prevalence in women in 1990 mimics that observed in men 40 years earlier. A substantial delay in the spread of the tobacco epidemic among men is apparent. In women, the delay in the initiation of the smoking epidemic ended with a quick diffusion of the habit.

The NHS in Catalonia, Spain, has reduced inequalities in the use of health services. Social inequalities remain in the use of those health services provided only partially by the NHS.