[Precocious neonatal mortality in premature newborns with low weight at birth and death]. / Mortalidad neonatal precoz en recien nacidos prematuros de bajo peso al nacer y de termino.

PIP: A retrospective study was conducted of all live births occurring in 1992 at a Dominican Institute of Social Security hospital in Santo Domingo to analyze the association between prematurity, low birth weight, and early neonatal mortality. Stillbirths, infants weighing less than 1000 g or born before 28 weeks of gestation, and those with lethal malformations were excluded. 5142 newborns met the inclusion criteria. 1701 deliveries (33%) were cesarean. 550 of the newborns (10.7%) were low birth weight, and 338 (6.6%) were premature. The early neonatal mortality rate was 17/1000. Low birth weight infants accounted for 66.2% of early neonatal mortality. 10.7% of low birth weight infants died within the first week of life, and their relative risk of early neonatal death was 16.42. 64% of all infants dying in their first week of life were also premature. The specific mortality rate for premature infants was 168.6/1000 live births. The relative risk was 25.32 for premature infants. Low birth weight infants born at term had an early neonatal mortality rate of 24.6/1000 live births, compared to 5.5/1000 for term births of adequate weight.^ieng

Neonatal size and infant mortality at high altitude in the western Himalaya.

A prospective study was undertaken in Ladakh, India, a high-altitude region of the Himalaya, to investigate the effects of small average birth size on neonatal mortality. While such studies exist from high-altitude regions of the New World and shed light on the adaptive status of high-altitude-dwelling populations there, this is the first to examine this relationship in the Himalaya. In a sample of 168 newborns, birthweight and other anthropometric measurements were reduced relative to Andean and Tibetan newborns. Logistic regression and hazard analysis showed that neonatal biological characteristics such as weight, fatness, and circumferences were important predictors of survival probabilities of infants, especially in the neonatal period. Low Rohrer's Ponderal Index (PI) was particularly strongly related to poor survival outcome. Males and females showed no significant differences in mortality risk. Data derived from reproductive histories revealed that neonatal mortality accounted for 70-80% of total infant mortality in Ladakh. Compared to other high-altitude studies, small newborn size in Ladakh was associated with much higher mortality risks; mortality risk rose dramatically with birthweights below the mean (2,764 grams), which characterized 50% of all newborns. It is argued that newborns in Ladakh are subject to strong directional selective forces that favor higher birthweights that incur lower risks of neonatal mortality, while Andean infants are subject to relatively mild selection pressure at both ends of the birthweight distribution. Given the overall small size at birth of Ladakhi newborns and the poor survival outcomes of newborns below the mean, it is suggested that this population is less well adapted in a biological sense to the stresses inherent in this high-altitude environment than are Andean populations, perhaps due to the relatively recent colonization of the area and the substantial genetic admixture that has occurred in the past.

[Probability of dying in the first year of life in an urban area of southern Brazil]. / Probabilidade de morrer no primeiro ano de vida em área urbana da região sul, Brasil.

A birth-cohort of 4,876 children born alive in hospital were selected and followed through up to the age of one year with a view to estimating the risk of dying in the first year of life. All of them were born in 1989, in one of the seven hospitals of an urban area of Southern Brazil and the only requirement for belonging to the cohort was that of residence on the area. The selected variables were: sex, birthweight, age at moment of death, underlying cause of death, and maternal age. The estimated probability of dying in the first year was of 19.9 per 1,000 (77.3% of the deaths occurred during the neonatal period). Perinatal causes and congenital malformations contributed to 80% of the deaths, and infectious diseases were the underlying cause of death in only 1.1% of the losses. The risk of dying in the first year of life due to afections arising during the perinatal period was higher among vaginally delivered babies (20.3 per 1,000) than it was for those born by cesarean section (9 per 1,000). A higher probability of death was present among infants born to adolescent mothers, and those with low birthweight (less than 2,500g). The results brought out the need for improving the quality of prenatal and infant care. They also suggested the hypothesis of a possible association between higher infant mortality and lower socio-economic level.

PIP: A birth cohort of 4876 children born alive in 7 hospitals in an urban area of southern Brazil was selected and followed through up to the age of one year, with a view to estimating the risk of dying in the first year of life. Information on death was collected from death certificates. A total of 103 deaths were located in Maringa, of which 97 occurred in 1989. All of them were born in 1989, and the only requirement for belonging to the cohort was that of residence in the area. The selected variables were: sex, birth weight (low, adequate, and normal), age at moment of death (neonatal, late neonatal, and post neonatal) underlying cause of death (according to the International Classification of Diseases--9th Revision), and maternal age. The estimated probability of dying in the first year was of 19.9 per 1000 (77.3% of the deaths occurred during the neonatal period) in contrast with the official rate of 22.6/1000. The probability of dying in late infancy was 4.5/1000 compared to 15.4 in neonatal age. Perinatal causes and congenital malformations contributed to 80% of the deaths, and infectious diseases were the underlying cause of death in only 1.1% of the losses. 63.8% of infant deaths were caused by ailments acquired in the perinatal period, yielding a probability of death of 12.3/1000. The risk of a female infant dying was 1.4 higher than that of a male. The risk of dying in the fist year of life owing to ailments arising during the perinatal period was higher among vaginally delivered babies (20.3 per 1000) than it was for those born by caesarian section (9 per 1000). A higher probability of death was present among infants born to adolescent mothers, and those with low birth weight (less than 2500 g). The results signify the need to improve the quality of prenatal and infant care, and suggest the possible association between high infant mortality and lower socioeconomic level.

Determinants of the evolution of the health situation of the population.

The objective of the present project is to evaluate the relative importance of different governmental social programmes for health development during the 1970's. National statistics available for the whole period and disaggregated to district level were analyzed with particular regard to three indicators of infant health status when the infant mortality rate was used, increased access to secondary care and improved socio-economic status were related to improvement in infant health status. When the percentage of neonatal deaths or the percentage of deceased live births per woman was used, neither the socio-economic improvement nor the assess to secondary did explain the improvement. Moreover, the primary health programme did not seem to be of importance in explaining the changes in the three indicators of infant health status. A second phase of the project, currently ongoing, is aimed at the evaluation of other factors such as the degree of efficiency of some of the health programmes. This study is based on directly collected information, quantitative as well as qualitative. Structured interviews have been used together with anthropological information from in-depth interviews with individuals and groups. The preliminary results of this second phase indicate that the contradictions observed in the first phase might be due to shortcomings in the national registers. In one of the study areas the coverage of PHC developed earlier than indicated by the official information. In other areas it was found that different obstacles as access problems, lack of health centers, socio-economical problems and lack of cultural knowledge reduced the effectiveness and impact of the primary health programmes.

PIP: Costa rica has achieved considerable success in social development and attention to the marginalized poor. The aim of this study is to assess the impact of health and nutrition from social interventions of the 1970s and to provide an explanation. Archival data on vital statistics from 1970 to 1984 and coverage of the Rural Health and Community Health Programs were used. In general, data were analyzed on the district level and in zones where population was sparse. Dependent variables were infant mortality under 1 year/live births, neonatal deaths 1-11 months/infant mortality, and mortality of live births/live births of women 20-24 years. Independent variables were health coverage, access to medical assistance, environmental conditions, educational status, rural residence, and the presence of modern living conditions. The results showed that major changes occurred in access to different health programs in rural and backward regions. National coverage was 60% in 1978. In 1980, 70% were covered by social security and 95% of all deliveries were medically assisted by trained health personnel. Electricity, water, and sanitation also improved. Independent variables were closely and inversely related to infant mortality around 1974 and declined in effect about 1983. Socioeconomic factors and access to health care became else important. There was less geographic variation in infant mortality. The percentage of postneonatal mortality and the percentage of live birth deaths continued to be strongly associated by the end of the period (1983). Correlation coefficients were generated for the absolute changes in the 2 measures of infant mortality for the time periods: 1973-75, 1976-78, and 1979-81. The results were all highly significant. Regions with low socioeconomic development and low access to health care and regions with high primary health care (PHC) had greater reductions in infant mortality. When the analysis was repeated with changes in independent variables, infant, mortality was reduced in regions with increases in secondary health programs, larger PHC coverage, and greater increases in standard of living measures. In a socioanthropological approach in 1988, preliminary results continued to show inconsistencies in the 3 infant mortality measures. Data deficiencies are suspected to be the cause and analysis is ongoing to correct for doubtful figures.