Variations in number of births and perinatal mortality by day of week in England and Wales.

Analysis of the births that occurred in England and Wales during 1970-6 showed that they followed a seven-day cycle, being concentrated from Tuesdays to Fridays and least numerous on Sundays. This pattern became increasingly pronounced during the period examined. Relatively few births occurred on bank holidays, especially Christmas Day and Boxing Day. In general perinatal mortality was higher among babies born at weekends than among those born on weekdays. It is likely that the pattern seen in the numbers of births is associated to a large extent with elective intervention. It is not possible to draw any conclusions about the pattern seen in perinatal mortality as so far the analysis has been confined to crude rates.     

Contribution of preterm delivery to perinatal mortality.

A detailed retrospective analysis was made of the records of 486 preterm infants, who accounted for 5-1% of all births during 1973 and 1974. Whereas preterm delivery did not contribute to perinatal mortality in terms of stillbirth, it outweighed all other causes in terms of early neonatal deaths. Preterm birth was responsible for 85% of the early neonatal deaths not due to lethal congenital deformities. Early neonatal mortality rates were closely linked both to gestational age and birth weight and to the reason for preterm birth. Early neonatal mortality was high (97 per 1000) when preterm labour was spontaneous, whether or not associated with material or fetal disease or with multiple pregnancy, but low (27 per 1000) when preterm delivery was elective. Preventing spontaneous preterm labour would considerably reduce neonatal mortality in our community.     

Intended place of delivery and perinatal outcome.

Data from the "1958 Perinatal Mortality Survey" have been analysed to assess differences in stillbirth and neonatal death rates according to the arrangements made for delivery. Only women aged 20-34 delivering at term, with no pregnancy abnormalities, were selected from three groups of women (normotensive primiparae, hypertensive primiparae, and normotensive women of parity 1, 2, or 3). Despite the fact that within each group the women booked for NHS consultant units were heavily weighted with adverse factors, the death rate of their infants was no more than 70% of that found among the women booked for either domiciliary, general practitioner unit, or private consultant delivery. Care and delivery in a NHS consultant unit carries least risk of death for the infant.     

Home visiting by general practitioners in England and Wales.

OBJECTIVE--To use data from the fourth national survey of morbidity in general practice to investigate the association between home visiting rates and patients'' characteristics. DESIGN--Survey of diagnostic data on all home visits by general practitioners. SETTING--60 general practices in England and Wales. SUBJECTS--502 493 patients visited at home between September 1991 and August 1992. MAIN OUTCOME MEASURES--Home visiting rates per 1000 patient years and home visiting ratios standardised for age and sex. RESULTS--10.1% (139 801/1 378 510) of contacts with general practitioners took place in patients'' homes. The average annual home visiting rate was 299/1000 patient years. Rates showed a J shaped relation with age and were lowest in people aged 16-24 years (103/1000) and highest in people aged > or = 85 years (3009/1000). 1.3% of patients were visited five or more times and received 39% of visits. Age and sex standardised home visiting ratios increased from 69 (95% confidence interval 68 to 70) in social class I to 129 (128 to 130) in social class V. The commonest diagnostic group was diseases of the respiratory system. In older age groups, diseases of the circulatory system was also a common diagnostic group. Standardised home visiting ratios for the 60 practices in the study varied nearly eightfold, from 28 to 218 (interquartile range 67 to 126). CONCLUSIONS--Home visits remain an important component of general practitioners'' workload. As well as the strong associations between home visiting rates and patient characteristics, there were also large differences between practices in home visiting rates. A small number of patients received a disproportionately high number of home visits. Further investigation of patients with high home visiting rates may help to explain the large differences in workload between general practices and help in allocation of resources to practices.     

Deprivation: explaining differences in mortality between Scotland and England and Wales.

To detect reasons for the difference in mortality between Scotland and England and Wales a measure of deprivation was studied, comprising overcrowding, unemployment of men, low social class, and not having a car. Data for Scotland for 1980-2 showed this measure to be strongly associated with mortality, with gradients being particularly steep in young adults. Deprivation was much severe in Scotland than in England and Wales. These findings suggest that much excess mortality may be ascribed to more adverse conditions. Standardising the mortality ratios to take account of the relative affluence and deprivation of the two populations led to the differentials observed being radically adjusted, while standardising for social class had little effect. Deprivation measures based on areas overcome many of the limitations associated with social class analysis and also show much greater discrimination between populations. Measures of deprivation apparently provide a powerful basis for explanation of health differences. Such measures should therefore form part of the 1991 census output to facilitate their use on a consistent basis.     

Parental age, parity and sex ratio in births in England and Wales, 1968-77

Variations in sex ratio with maternal age, paternal age, parity, and time are examined in data on all legitimate births in England and Wales, 1968-1977. Significant linear declines in sex ratio with both increasing parity and increasing paternal age, and a curvilinear relationship with maternal age are found. Results show that 1) before 1955 it seems likely that the sex ratio declined with an increase in maternal age, 2) between 1955 and 1968 there was an unexplained decline in the sex ratio of births to women aged 20-24 and an increase in that of births to women aged 30-34, and 3) there was no significant secular trend in sex ratio during the period 1968-1977. Using data provided by the Registrar General of England and Wales, a weighted multiple regression analysis is applied. Some possible explanations for the changes in sex ratios of births during the years studied are: 1) racial heterogeneity, 2) artificial insemination, 3) the pill, and 4) ovulation induction. Overall, some artifact or combination of artifacts has transformed the regression of sex ratio on maternal age from a monotonic decline to a cubic, or this hypothesis stands in need of modification.     

Patterns of mortality among migrants to England and Wales from the Indian subcontinent.

Causes of deaths in immigrants to England and Wales from the Indian subcontinent were assessed by ethnic subgroup. Observed and expected deaths for 1975-7 were aggregated to calculate proportional mortality ratios. Observed mortality due to infective and parasitic diseases, endocrine diseases (notably diabetes), diseases of the circulatory system (notably ischaemic heart disease and cerebrovascular disease, in males), and diseases of the digestive system (notably cirrhosis of the liver) exceeded expected mortality. Fewer than expected deaths were due to malignant neoplasms (notably lung cancer and chronic bronchitis); proportional mortality ratios for cancer were lower for Hindu groups than for Moslems and were lowest for Punjabis. Mortality due to ischaemic heart disease, high in all groups, was highest in Moslems. Significantly more Punjabi males died from cerebrovascular disease and cirrhosis of the liver. Diabetes was commonest among Gujaratis. The variation seen in the patterns of mortality in the different ethnic groups indicates the need for further epidemiological and health service research centred on these communities.     

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.     

Patterns of mortality in second generation Irish living in England and Wales: longitudinal study.

OBJECTIVE--To examine the mortality of second generation Irish living in England and Wales. DESIGN--Longitudinal study of 1% of the population of England and Wales (longitudinal study by the Office of Population Censuses and Surveys (now the Office for National Statistics)) followed up from 1971 to 1989. SUBJECTS--3075 men and 3233 women aged 15 and over in 1971. MAIN OUTCOME MEASURES--Age and sex specific standardised mortality ratios for all causes, cancers, coronary heart disease, cerebrovascular diseases, respiratory diseases, and injuries and poisonings. Deaths were also analysed by socioeconomic indicators. RESULTS--786 deaths were traced to men and 762 to women. At working ages (men, aged 15-64; women, 15-59) the mortality of men (standardised mortality ratio 126) and women (129) was significantly higher than that of all men and all women. At ages 15-44, relative disadvantages were even greater both for men (145) and for women (164). Mortality was raised for most major causes of death. Significant excess mortality from cancers was seen for men of working age (132) and for women aged 60 and over (122). At working ages mortality of the second generation Irish in every social class and in the categories of car access and housing tenure was higher than that of all men and all women in the corresponding categories. Adjusting for these socioeconomic indicators did not explain the excess mortality. CONCLUSION--Mortality of second generation Irish men and women was higher than that of all men and all women and for most major causes of death. While socioeconomic factors remain important, cultural and lifestyle factors are likely to contribute to this adverse mortality.     

Sudden infant death syndrome and postneonatal mortality in immigrants in England and Wales.

To examine ethnic differences in postneonatal mortality and the incidence of sudden infant death in England and Wales during 1982-5 records were analysed, the mother''s country of birth being used to determine ethnic group. Postneonatal mortality was highest in infants of mothers born in Pakistan (6.4/1000 live births) followed by infants of mothers born in the Caribbean (4.5) and the United Kingdom and Republic of Ireland (4.1). Crude rates were lower in infants of mothers born in India (3.9/1000), east and west Africa (3.0), and Bangladesh (2.8) than in infants of mothers born in the United Kingdom despite less favourable birth weights. Mortality ratios standardised separately for maternal age, parity, and social class were significantly higher in infants of mothers born in Pakistan and lower in those of mothers born in Bangladesh. The ratio for infants of Caribbean mothers was significantly higher when adjusted for maternal age. Ratios for infants of Indian and east African mothers did not show significant differences after standardisation. An important finding was a low incidence of sudden infant death in infants of Asian origin. This was paralleled by lower mortality from respiratory causes. During 1975-85 postneonatal mortality in all immigrant groups except Pakistanis fell to a similar or lower rate than that in the United Kingdom group; Pakistanis showed a persistent excess. During 1984-5 several immigrant groups (from the Republic of Ireland, India, west Africa, and the Caribbean) recorded an increase in postneonatal mortality. Surveillance of postneonatal mortality among ethnic communities should be continued, and research is needed to identify the causes underlying the differences.     

"I'm all right,John": voting patterns and mortality in England and Wales, 1981-92.

OBJECTIVE: To investigate the association between voting patterns, deprivation, and mortality across England and Wales. DESIGN: Ecological study. SETTING: All the electoral constituencies of England and Wales. MAIN OUTCOME MEASURES: Combined and sex specific standardised mortality ratios. RESULTS: For the years surrounding the three elections of 1983, 1987, and 1992 overall standardised mortality ratios showed substantial negative correlations of -0.74 to -0.76 with Conservative voting and substantial positive correlations of 0.73 to 0.77 with Labour voting (all P < 0.0001). Correlations were higher for male than female mortality. Conservative voting was strongly negatively correlated (r = -0.84) with the Townsend deprivation score, while Labour voting was positively correlated (r = 0.74) with this. Labour and Conservative voting explained more of the variance in mortality than did the Townsend score. In multiple regression analyses for the 1992 election Labour voting (P < 0.0001), Conservative voting (P < 0.0001), the Townsend score (P = 0.016), and abstentions (P = 0.032) were all associated with mortality. Labour and conservative voting explained 61% of the variance in mortality between constituencies; when Townsend score and abstentions were added this increased to 63%. CONCLUSIONS: Conservative and Labour voting are at least as strongly associated with mortality as is a standard deprivation index. Voting patterns may add information above that provided by indicators of material deprivation. People living in better circumstances and who have better health, who are least likely to require unemployment benefit and free school meals or to rely on a state pension in old age, and who are most able to opt out of state subsidised provision of transport, education, and the NHS, vote for the party that is most likely to dismantle the welfare state.