Stephen N Wall

Very Low Birthweight in African American Infants: The Role of Maternal Exposure to Interpersonal Racial Discrimination

OBJECTIVES We determined whether African American womens lifetime exposure to interpersonal racial discrimination is associated with pregnancy outcomes. METHODS We performed a case-control study among 104 African American women who delivered very low birthweight (<1500 g) preterm (<37 weeks) infants and 208 African American women who delivered non-low-birthweight (>2500 g) term infants in Chicago, Ill. RESULTS The unadjusted and adjusted odds ratio of very low birthweight infants for maternal lifetime exposure to interpersonal racism in 3 or more domains equaled 3.2 (95% confidence intervals=1.5, 6.6) and 2.6 (1.2, 5.3), respectively. This association tended to persist across maternal sociodemographic, biomedical, and behavioral characteristics. CONCLUSIONS The lifelong accumulated experiences of racial discrimination by African American women constitute an independent risk factor for preterm delivery.

Low-income African-American mothers' perception of exposure to racial discrimination and infant birth weight

We performed a hospital-based case-control study of African-American mothers to explore the relation between a mothers perception of exposure to racial discrimination during pregnancy and very low birth weight. We administered a structured questionnaire to low-income mothers of very low birth weight (<1500 gm; N = 25) and non-low birth weight (>2500 gm; N = 60) infants. The unadjusted and adjusted odds ratio of very low birth weight for maternal exposure to racial discrimination were 1.9 (0.5-6.6) and 3.2 (0.9-11.3), respectively. We conclude that maternal perception of exposure to racial discrimination during pregnancy may be associated with very low birth weight in their infants.

Infant mortality from congenital malformations in the United States, 1970-1997.

OBJECTIVE We examined a trend in infant mortality caused by congenital malformations in the United States, particularly for the racial disparity between whites and nonwhites. METHODS We used US annual summary data on cause‐specific infant mortality for 1970–97 and detailed birth and infant death linked data for 1985–87, 1989–91, and 1995–97. RESULTS Congenital malformations became a more prominent cause of infant mortality in 1997 and accounted for 22.1% of all infant deaths compared with 15.1% in 1970. Congenital malformations of nervous, cardiovascular, and respiratory systems accounted for more than 60% of all malformation deaths. Malformations incompatible with life (anencephaly, encephalocele, hypoplastic lungs, renal agenesis, and trisomies 13 and 18) were the cause of one‐third of all malformation deaths. In 1970–71, infant mortality caused by congenital malformations in nonwhites was lower, 2.6 (confidence interval [CI] 2.5, 2.7) per 1000, compared with whites, 3.1 (CI 3.0, 3.1) per 1000. However, in 1996–97, the rate of congenital malformation‐specific infant mortality was higher in nonwhites, 1.7 (CI 1.7, 1.8) per 1000, compared with whites, 1.6 (CI 1.5, 1.6) per 1000. This trend was most pronounced with central nervous system malformations. Although whites had an almost two‐fold higher infant mortality rate from central nervous system malformations compared with nonwhites in 1970–71, this disparity was no longer present by 1996–97. CONCLUSION Congenital malformations have become a leading cause of infant mortality in the 1990s. Over the last several decades, this mortality declined more slowly in nonwhites than in whites.

Perinatal death and tocolytic magnesium sulfate

Objective To determine whether there is a significant association between perinatal mortality and exposure en route for total doses of tocolytic magnesium sulfate larger than 48 g. Methods We did a case-control study in which cases were defined as neonates or fetuses who died after being exposed to tocolytic magnesium sulfate and controls were those who survived exposure. The study included fetuses and neonates who weighed between 700 and 1249 g and whose mothers had received tocolytic magnesium sulfate at Chicago Lying-in Hospital between January 1, 1986, and March 31, 1999. We excluded women who received prophylactic magnesium sulfate for preeclampsia or preeclampsia superimposed on chronic hypertension, and fetuses or neonates with major congenital anomalies. Data were analyzed by Fisher exact test, χ2 test, Student t test, Mann–Whitney U test, multivariable logistic regression, and Cochrane–Armitage trend test. Results Controlling for birth weight or gestational age, year of delivery, receipt of betamethasone, acute maternal disease, and maternal race in a multivariable model, we found that exposure to total doses of tocolytic magnesium sulfate exceeding 48 g was significantly associated with increased perinatal mortality (adjusted odds ratio 4.7; 95% confidence interval 1.1, 20.0; P = .035). Using the Cochrane–Armitage trend test, we found that a significant dose response was present (P = .03), but one that was most consistent with a threshold effect. Conclusion Our findings support the hypothesis that high doses of tocolytic magnesium sulfate are associated with increased perinatal mortality among fetuses and neonates weighing 700–1249 g.

Trend in mortality from respiratory distress syndrome in the United States, 1970-1995☆☆☆

OBJECTIVE We examined the trend in mortality caused by respiratory distress syndrome (RDS) and its impact on changes in infant and neonatal mortality rates (IMR, NMR) in the United States. STUDY DESIGN Data on infant deaths in the United States for the period 1970 through 1995 were used to compare RDS-specific IMR to other cause-specific IMR. Data from the U.S. birth cohorts of 1985 through 1991 were used to examine birth weight- and RDS-specific NMRs. RESULTS IMR from RDS declined from 2.6 per 1000 live births in 1970 to 0.4 per 1000 in 1995. More than three quarters of this decline occurred between 1970 and 1985. RDS-specific NMR declined by 13% between 1985 and 1988 and by more than twofold greater, that is, 28%, between 1988 and 1991. There was also a significant reduction in postneonatal mortality from chronic lung diseases between 1988 and 1991. CONCLUSIONS Most of the reduction in mortality from RDS occurred before the introduction of surfactant therapy. The recent accelerated reduction in mortality from RDS between 1988 and 1991 was temporally associated with widespread use of surfactant therapy and was the single most important factor for reduction in overall NMR in the United States.

Risk of Low Birth Weight Associated with Advanced Maternal Age Among Four Ethnic Groups in the United States

Objectives: To examine and compare the risk of low birth weight associated with delayed childbearing in four ethnic groups using nationally representative data in the United States. Methods: We compared the risk of low (<2.5 kg) birth weight among African Americans, Mexican Americans, Puerto Ricans, and non-Hispanic whites using birth data for the United States obtained from the National Center for Health Statistics. Comparisons were done separately for first births and births of second or higher order and in terms of odds ratios, risk differences and attributable fractions of very low (<1.5 kg), middle low (1.5–2.5) and overall low birth weight. Statistical analysis included use of logistic regression models with likelihood ratio tests for interaction effects. Results: African Americans and Puerto Ricans, and to a lesser extent Mexican Americans, had higher risk differences associated with advanced maternal age. For first births, the risk differences associated with advanced maternal age (≥35 years) in low birth weight were 5.3% (95% CI, 4.7–6.0), 4.3% (95% CI, 1.7–6.9), and 3.7% (95% CI, 2.8–4.5) for African Americans, Puerto Ricans, and Mexican Americans, respectively, as compared with 2.6% (95% CI, 2.4–2.7) for non-Hispanic whites. On the other hand, the odds ratios associated with advanced maternal age were more similar across the four ethnic groups. Differences were greater for all ethnic groups in the case of first births as compared with births of second or higher order. Conclusions: Advanced maternal age appears to be associated with for the most part similarly increased odds of low birth weight for African Americans, Mexican Americans, Puerto Ricans, and non-Hispanic whites. However, the age-related increments in the risk of low birth associated with advanced maternal age are greater for African Americans, Puerto Ricans and, to a lesser extent, Mexican Americans, as compared with non-Hispanic whites.

Racial differences in respiratory-related neonatal mortality among very low birth weight infants.

OBJECTIVE To examine racial differences in the secular trends in respiratory-related neonatal mortality among very low birth weight (VLBW) infants in the United States, temporally associated with surfactant availability. DESIGN Comparison of time trends in African American and non-Hispanic white (NHW) VLBW infants of cause-specific neonatal mortality and neonatal and infant mortality for 2 consecutive 3-year periods. RESULTS From 1985 to 1988 there was no racial difference in the rate of decline of each mortality outcome. From 1988 to 1991 rates of decline in neonatal mortality caused by respiratory distress syndrome and by all respiratory causes were significantly greater for NHWs compared with African Americans. However, the rate of decline in nonrespiratory neonatal mortality was similar for African Americans and NHWs. Compared with African American VLBW infants, NHWs had a greater rate of decline in both neonatal (31% vs 20%; P <.01) and infant mortality (32% vs 21%; P <.01) during this period. CONCLUSIONS Between 1988 and 1991, declines in neonatal mortality risks caused by respiratory distress syndrome and all respiratory causes were greater for NHW infants than for African American VLBW infants. The decline in nonrespiratory mortality risk showed no racial differences. These findings suggest possible racial disparities in timely access or racial differences in the efficacy of respiratory treatments for VLBW infants.

Hospital Factors and Nontransfer of Small Babies: A Marker of Deregionalized Perinatal Care?

OBJECTIVES: Our purpose was to examine the contribution of hospital factors (e.g., reimbursement sources, teaching status) to the rate of nontransfer of <1250 g infants born in nontertiary hospitals in Illinois. We chose nontransfer as a marker of the extent to which there have been structural changes in the regionalized perinatal care system in Illinois.STUDY DESIGN: Using data from live birth certificates (1989–1996), from the American Hospital Associations Annual Survey of Hospitals (1990 to 1996), and Illinois hospital discharge records (1992 to 1996), we simultaneously assessed the effect of hospital and individual factors on nontransfer of infants <1250 g (n=2904).RESULTS: When adjusted for individual risk factors, several hospital factors were associated with nontransfer. These include birth in a Level II+hospital (odds ratios(OR) 3.75; 95% CI 2.29, 5.29), high Medicaid revenues (OR 1.97; 95% CI 1.58, 2.47), high HMO revenues (OR 1.39; 95% CI 1.11, 2.28), and status as a teaching hospital (OR 1.63; 95% CI 1.30, 2.09).CONCLUSIONS: This study suggests that there should be careful consideration of the role of hospital factors in perinatal deregionalization in order to preserve the improvements in maternal and infant outcomes associated with regionalized perinatal care.

Multilevel Analysis of the Effects of Low-Income Residence on the Risk of LBW Associated with Advanced Maternal Age in African-Americans and Whites |[dagger]| 1366

Purpose: Advanced maternal age (AMA), or age greater than 34 years old, is a known risk factor for LBW among African Americans (AA) and whites. It has been suggested that this risk may be increased by conditions of social disadvantage. We hypothesized that exposure to poverty would increase the risk of LBW associated with AMA among both AA and whites. We utilized a multi-level analysis to assess whether income level of maternal residence would increase the risk of LBW associated with AMA, after adjusting for traditional individual risk factors.

Racial Differences in Secular Trends in Respiratory-Related Neonatal Mortality among VLBW Infants in the US

Racial Differences in Secular Trends in Respiratory-Related Neonatal Mortality among VLBW Infants in the US