A comparison of recent trends in infant mortality among twins and singletons

Overall infant mortality rates have steadily declined in recent years. The goal of this study was to examine whether recent declines in infant mortality were similar for twins and singletons, and to assess the impact of differing birthweight distributions on these relationships. Linked birth and infant death records for 1985-86 and 1995-96 were used to calculate infant mortality rates for twins and singletons for the two time periods. Bootstrap simulations were used to estimate rates of decrease between the two time periods and to determine whether these rates differed between twins and singletons. Between 1985-86 and 1995-96, infant mortality among twins declined significantly faster than among singletons (36% vs. 29%, P < 0.05). This difference was true for both black and white infants (black: 28% for twins vs. 22% for singletons; white: 38% for twins vs. 31% for singletons). Within birthweight categories, infant mortality declined more rapidly among twins than among singletons, although differences were not always significant. Factors and circumstances that contributed to the infant mortality decline in the United States have benefited twins to a greater extent than singletons.     

State trends in infant mortality, 1968-83.

This paper presents an analysis of state trends in infant mortality rates (IMRs) for 1968-83. In order to take into account the large random error component associated with state IMRs, weighted least squares estimates are used to fit log-linear models to these trends. Using simulated data, these estimates are shown to be nearly unbiased and to provide valid significance tests. However, the power to detect changes in trend is rather limited, especially in small states. Using these methods, separate analyses of White IMRs in 49 states and non-White IMRs in 30 states were completed. Nine states are identified which had infant mortality trends less favorable than the national experience and 1981-83 rates more than 5 per cent above the national average.     

Preventing and postponing death: trends in Tennessee infant mortality.

Infants born in Tennessee between 1984 and 1988 experienced reduced mortality compared with those born in the 5 years previous. For all birthweight singleton infants, the reduction from 10.2 to 8.4 deaths per 1000 live births represents an 18% decline in mortality. The most impressive gain made was for very low birthweight (less than 1500 g) infants in the neonatal period, where mortality was reduced 24%. However, for these infants there was nearly a sixfold increase in the postneonatal mortality associated with prematurity-related causes.     

Analysis of recent trends in cardiovascular mortality in Switzerland

Summary During the last decade (1970–1980), the cardiovascular mortality rate, based on the mention of a cardiovascular disease as the primary cause of death, has decreased in all age groups in Switzerland. This decrease is greater in the female population. However, the mortality rate of ischemic heart diseases continues to increase in the 60 plus age group. If all deaths where a cardiovascular disease is reported, as either the primary or immediate cause, are considered, the decrease is less marked. The reason seems to be an increase in the number of deaths due to cancer, where a cardiopathy is reported as the immediate cause.

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Eine Trendanalyse der kardiovaskulären Mortalität in der Schweiz

Zusammenfassung Die kardiovaskuläre Mortalität, analysiert anhand der gemeldeten primären Todesursachen, ging im letzten Jahrzehnt in allen Altersklassen zurück. Dieser Rückgang war bei den Frauen ausgeprägter. Hingegen stieg die Sterblichkeit an ischämischen Herzkrankheiten bei den über Sechzigjährigen weiter an. Berücksichtigt man für die Analyse alle Todesfälle, bei denen als primäre oder als unmittelbare Todesursache eine kardiovaskuläre Krankheit gemeldet wurde, so ist der Rückgang weit weniger deutlich. Dieser Unterschied kann durch den zunehmenden Anteil der Krebstodesfälle mit einer kardiovaskulären unmittelbaren Todesursache erklärt werden.

     

Background on recent trends in mortality in the Netherlands

In the Netherlands, a considerable reduction in the annual number of deaths occurred in 2004. This reduction was largely caused by a decrease in the number of deaths from cardiovascular disease. - The risk of dying from cardiovascular disease has decreased in an almost linear manner during the past few decades. This reduction, which was well above average in the case of ischaemic heart disease, was registered for both sexes and across all age groups. The risk reduction in men aged 30-59 years was particularly large. - The contribution of neoplasms to total mortality continues to increase. However, the risk of dying from certain forms of cancer (lung for men, colon for women, stomach, gall-bladder, breast, prostate, uterus and ovaries) has been decreasing since the 1990s. - The risk of dying from breast cancer has decreased since the end of the 1990s. If present trends continue, Dutch women will be more likely to die from lung cancer than breast cancer from 2007 onwards. - The remarkably low mortality in 2004 may be attributed to the equable climatic conditions and the absence of an influenza epidemic. The drop in mortality was short-lived: in the first quarter of 2005, influenza caused a very strong increase in mortality among those aged over 80 years. - Even a further substantial reduction in mortality risks will not be able to prevent the predicted increase in the annual number of deaths in the Netherlands. This increase is estimated to end by the middle of this century.     

Reproductive mortality in the United States: recent trends and methodologic considerations.

Between 1975 and 1982, the annual number of deaths attributable to pregnancy and childbirth, induced abortion, and contraception in the United States declined from 1,083 to 751. The mortality rates for each of these components decreased by 35,89, and 35 per cent, respectively, and the overall reproductive mortality rate dropped by 35 per cent. The death rate due to pregnancy and childbirth is 25 times greater than that due to induced abortion and eight times more than that to contraceptive-associated mortality. In 1982 nearly 30 million women used contraceptives, while slightly fewer than four million women were pregnant to term. The decrease in contraceptive-associated mortality between 1975 and 1982 probably reflects a combination of safer contraceptives, fewer women using contraceptive methods that may not be safest for them, and an increasing number of sterilizations, which remove women from the group at highest risk of contraceptive-related mortality. Maternal mortality appears to be slowing its rate of decline, while induced abortion mortality has been very low since the legalization of abortion.     

Cohort-specific trends in stroke mortality in seven European countries were related to infant mortality rates

OBJECTIVES: To assess, in a population-based study, whether secular trends in cardiovascular disease mortality in seven European countries were correlated with past trends in infant mortality rate (IMR) in these countries. STUDY DESIGN AND SETTING: Data on ischemic heart disease (IHD) and stroke mortality in 1950-1999 in the Netherlands, England & Wales, France, and four Nordic countries were analyzed. We used Poisson regression to describe trends in mortality according to birth cohort, for the cohorts born between 1860 and 1939. Pearson correlation coefficients were calculated to determine associations between IMR and IHD, or stroke mortality. RESULTS: IHD mortality increased for successive cohorts up to 1900, and then started to decline. Stroke mortality levels were virtually stable among birth cohorts up to 1880, but declined rapidly among later cohorts. A strong positive association was found between cohort-specific IMR levels and stroke mortality rates. There were no strong cohort-wise associations between IMR and IHD mortality. CONCLUSION: These results support other studies in suggesting that living conditions in early childhood may influence population levels of stroke mortality. Future studies should determine the contribution of specific early life factors to the mortality decline in IHD and especially stroke.     

Socioeconomic correlates and trends of infant mortality rate in Goa and Kerala

Infant mortality trends are projected for Goa and Kerala states in India for the year 2000. The impact of the net domestic product, the population per doctor, and literacy on infant mortality are assessed. Data are obtained from the Indian Yearbooks for 1990-91. The Gompertz curve was used to project the infant mortality rate per 1000 live births to the year 2000. Infant mortality in the year 2000 was estimated to be 17.02 in Goa and 20.22 in Kerala. A highly significant correlation was found between the infant mortality rate and literacy and the net domestic product in Goa. In Kerala only literacy was statistically significantly related to infant mortality. The population per doctor was found to be significantly positively related to the infant mortality rate in both Goa and Kerala. 82.96% of infant mortality in Goa was explained by the three factors. 79.33% of infant mortality in Kerala was explained by these same factors. The view is taken that program effort should be directed to improving literacy, economic conditions, and medical doctor coverage as a means of reducing infant mortality.     

Fertility and infant mortality trends in Nicaragua 1964-1993. The role of women''s education

OBJECTIVES: To assess trends in fertility and infant mortality rates (IMR) in León, Nicaragua, and to examine the effect of women's education on these trends during 1964-1993, a period of rapid social change. DESIGN: Cross sectional survey, based on random cluster sampling. A retrospective questionnaire on reproductive events was used. SETTING: The municipality of León, which is the second largest city in Nicaragua, with a total population of 195,000 inhabitants. SUBJECTS: 10,867 women aged 15-49 years, corresponding to 176,281 person years of reproductive life. Their children contributed 22,899 person years under 12 months of age to the IMR analysis. MAIN OUTCOME MEASURES: Fertility rate (number of pregnancies per 1000 person years) for specific age groups and calendar periods, total fertility rate, and IMR. RESULTS: Fertility rates and IMR declined in parallel, especially during the 1980s. However, education specific fertility rates did not decline, but the proportion of educated young women increased from 20% to 46%. This had also an impact on the overall IMR decline, although IMR reduction mainly took place among infants of women without formal education, decreasing from 118 to 69 per 1000 during the observation period. CONCLUSIONS: In this demographic transition over three decades, fertility and IMR declined simultaneously. The decreasing trend in fertility was mainly explained by an increase in women's education, while the IMR decline seemed to be the result of health interventions, specially targeted to poorer groups of women and their infants. Thus, social differences in fertility rates remained unchanged, while equity in chances of child survival increased.     

Regional disparities in infant mortality in Canada: a reversal of egalitarian trends

Background  

Although national health insurance plans and social programs introduced in the 1960s led to reductions in regional disparities in infant mortality in Canada, it is unclear if such patterns prevailed in the 1990s when the health care and related systems were under fiscal duress. This study examined regional patterns of change in infant mortality in Canada in recent decades.     

Basic trends of infant mortality in the Volga Region in the 1990s

Results of the study on the structure and trends of mortality rates in infants of the first year of life in the Volga region showed great differences among the areas comprising the region. Various trends for infant mortality were found to be decreased. Analyzing the structure of mortality also indicated considerable regional differences: the Astrakhan region was leading in some infectious and parasitogenic diseases; respiratory diseases prevailed in the Astrakhan and Saratov Regions,; the Penza, Ulyanovsk and Volgograd regions were registered to have the largest number of disorders occurring in perinatality; the Volgograd and Ulyanovsk Regions showed the largest number of congenital disorders (malformations), deformities and chromosomal disorders. Maternity and child protection requires a further and more active participation of the state.     

The recent decrease in CHD mortality.

Between 1968 and 1973 coronary heart disease (CHD) mortality in the United States decreased for 4 out of 5 consecutive years. This is in marked contrast with the increasing trend prior to 1960 and the flat trend in the 1960's. All race, sex and adult age groups experienced a decrease between 1968 and 1972, the overall age-adjusted rate decreasing 7.3% during this period. Decreases of similar magnitudes also occurred for all causes of death combined and for every major cause except cancer, violence, and cirrhosis of the liver.Although the recent decrease in the mortality rate for CHD has been small, the decrease appears to be real. Most of the decrease, however, appears to be due to epidemic fluctuations in the incidence of the respiratory diseases. It is concluded that fluctuations in CHD mortality since the early 1960's are largely minor perturbations arising from extraneous sources rather than from changes in the incidence or prognosis of this disease.     

Priority trends in the realization of complex programs aimed at decreasing infant mortality in the regions of high mortality rate

Approaches to reducing infant mortality in southern regions of USSR are outlined. Middle Asia and Kazakhstan comprise 16.7% of the USSR population; the birth rate in this region is 34-39/1000, and the birth interval is 2 years (often, 1 year). Infant mortality rate is 25/1000 births; more than 46% of children die during the 1st year of life. In the structure of infant mortality, infections and respiratory diseases are dominant. The peak of infant morality occurs during the summer (July-September). Special surveys indicated an unsatisfactory state of health of pregnant women associated with nutritional deficiency, observance of certain religious customs, and occupational exposure to agricultural chemicals. The adopted program for the regions with high infant mortality consists of the following priority measures: family planning and birth control; improvement of the health of women of child-bearing age; nutrition of pregnant women; breast feeding for mothers with young children; strict adherence to the labor laws for working women; improvement of the social and legislative assistance to a family; improvement of the system of outpatient care facilities for large families; development of a system of emergency care; carrying out social, hygienic and medical measures of control of intestinal and other hospital infections; drastic changes in the methods and style of educational campaign; campaign against harmful customs; development of the system of medical genetic care and prenatal diagnosis; improvement of the training of medical personnel.