Are there racial disparities in infant mortality and prematurity?

September 1, 2013

The epidemiology of racial disparity in prematurity and infant mortality is a complex problem, say the authors, and public health programs are part of the solution.

 

Dr. Brown is the Roy T. Parker Professor and Chair, Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Duke University Medical Center, Durham, North Carolina.

Mr. Smith is Assistant Evaluator, Indianapolis Healthy Start, Division of Maternal and Child Health, Marion County Public Health Department, Indianapolis, Indiana.

Ms. Beasley is Director, Maternal and Child Health, Marion County Public Health Department, and Project Director, Indianapolis Healthy Start, Indianapolis, Indiana.

 

Reducing infant mortality (deaths in the first year of life) has long been a national priority of the United States. Since 1935, US rates of infant mortality have fallen by more than 400%, mostly due to early detection and treatment of complications (Figure). Despite this success, the current model is challenged to address health problems far outside the scope of the doctor’s exam room. Currently, the World Health Organization (WHO) ranks the United States 41st among 193 other nations in infant mortality, largely due to variations in infant mortality associated with race and ethnicity.

Authors from the National Center for Health Statistics wrote nearly 50 years ago in one of the first public health reports on infant mortality, “although the national infant mortality rate is now at its lowest level, the prospects for a change in the rate of decline in the future do not appear to be as favorable now as they did in 1958 . . . The gap between the rate for white and nonwhite infants has widened during the past decade.”

The leading causes of death among newborns during the first year of life are related to prematurity and congenital anomalies. Prematurity as a cause of infant mortality affects non-Hispanic blacks at a rate 3 times higher than non-Hispanic whites. The epidemiology of prematurity and racial disparity of spontaneous preterm birth is quite complex. In 2005, the Institute of Medicine (IOM) estimated the annual price tag for prematurity in the US at $26 billion.1

While researchers have long known the impact of social determinants on health behaviors, most public health agencies have focused resources on health education and early prenatal care to reduce infant mortality. In 2007, the IOM recognized the growing importance of social and health determinants, stating:

Preterm birth is a complex cluster of problems with a set of overlapping factors of influence. Its causes may include individual level behavioral and psychosocial factors, neighborhood characteristics, environmental exposures, medical conditions, infertility treatments, biological factors, and genetics. Many of these factors occur in combination, particularly in those who are socioeconomically disadvantaged or who are members of racial and ethnic minority groups.1

Because of the recognized complexities in epidemiology of prematurity, in 2010 the Maternal and Child Health Bureau (MCHB) of the US Department of Health and Human Services released a concept paper that applied life course theory (LCT) to its long-term strategic plan to reduce racial and ethnic disparities in infant mortality. 2 LCT suggests that an individual’s environment and culture heavily influence manifestation and management of disease. Social, economic, and environmental inequities persist across generations, collectively limiting individuals’ future health and creating variations in incidence and impact of many diseases. Implicit within LCT are 4 tenets. We will discuss each one as it relates to a particular health behavior and discuss how some interventions use LCT to address the underlying roots of variations in infant mortality.

NEXT: Infant mortality graph by race >>

 

 

LCT Tenet 1: Timelines. Health behaviors and attitudes persist across generations, often handed down from parent to child.

Intimate partner violence

Intimate partner violence (IPV) not only acts as a barrier to prenatal care but also results in physical injury, psychological trauma, and sometimes death. Abused women experience more physical health problems and have a higher occurrence of depression; anxiety and stress; tobacco, illicit drug, and alcohol abuse; and suicide attempts, in addition to using more healthcare services. In 2003, the Centers for Disease Control and Prevention (CDC) estimated that IPV accounted for more than 1500 deaths annually, with a price tag of $5.8 billion due to lost productivity and use of healthcare services.3

Witnessing violence between one’s parents and caretakers is the strongest risk factor for transmitting violent behavior from one generation to the next.3 Therefore the effects of IPV extend far beyond the period of abuse. Perpetrators of IPV are 30%–60% more likely to abuse children in the home, and boys who witness violence are twice as likely to abuse their partners and children when they grow up.4

Parker and others demonstrated the efficacy of programs that teach safety behaviors and build empowerment skills to reduce different types of IPV.5 More recent IPV interventions have developed integrated models that include other cognitive behavioral interventions to address overlapping health determinants. They have shown significant reductions in IPV as well as rates of prematurity.6

LCT Tenet 2: Timing. Periods of vulnerability influence lifelong health as well as social and economic trajectories.

Smoking and smoking cessation

The health and economic consequences from smoking are well documented. Smoking during pregnancy is linked to up to 10% of all infant deaths. The direct medical costs of a complicated birth are 66% higher for smokers than for nonsmokers, reflecting the more severe complications and a requirement for more intensive care. Direct medical costs associated with tobacco use and exposure to secondhand smoke during pregnancy are estimated to be $4.6 billion.7

Research has shown that parental smoking can contribute to smoking initiation independent of other risk factors such as depression and anxiety.8 Once the habit of daily smoking begins, most smokers find it very difficult to quit and average 6 attempts before becoming former smokers.9

Despite the challenges of quitting smoking, pregnancy is a defining moment in many women’s lives when they focus on their own health and the health of their fetus. Women who smoke and become pregnant are twice as likely to attempt to quit smoking as nonpregnant women.10 According to the March of Dimes, most pregnant smokers will attempt to quit, but 80% will resume smoking within 6 months after giving birth. Women who quit smoking before the age of 35 have lifespans similar to women who never smoked.11

Many efficacious smoking cessation programs exist, yet relatively few are for pregnant women. The March of Dimes developed a motivational counseling program called the 5 As. The 5 As (ask, advise, assess, assist, arrange) program is based on a woman’s needs and can be offered by health educators, social workers, and healthcare workers. Published research suggests that this program can increase smoking cessation rates by 30%.

 

 

LCT Tenet 3: Equity. Diseases and treatments affect individuals (eg, race), families (eg, cultural beliefs), and communities (eg, environment) differently, leading to variations in disease incidence, prevalence, and impact.

Obesity

By age 65, approximately 1 in 4 US adults are obese and another 34% to 47% are considered overweight (having a body mass index [BMI] of 25 to < 30).11 The medical consequences of adult obesity are well known. The medical costs of treating obesity are approaching $150 billion each year.12 Obstetric complications as a result of obesity and its comorbidities increase the risk of adverse outcome for both mother and baby. The increasing prevalence of obesity in the United States was a factor behind the IOM’s reexamination of the recommended weight gain guidelines during pregnancy, which subsequently limited the maximum weight gain for most women. Breastfeeding also plays an important role in helping women achieve healthier interconception weight, and may impact childhood and adult obesity. Surveys of women who gave birth in 2004–2005 in 26 states showed that race or ethnicity coupled with geographic location had the largest impact on rates of prepregnancy obesity, which ranged from 7.3% in white, non-Hispanic women living in New York City to 34.7% in Hispanic women living in Michigan.13

New “lifestyle case management” approaches (such as the Strong Healthy Women program) that include individual and group education, support, and referrals can be effective because they take a more holistic approach and can be tailored to specific racial and ethnic groups located in specific communities. The Indianapolis Healthy Start Program developed a program called Fruits of Our Labor that includes healthy weight education, nutrition support groups, and referrals to cooking programs, fitness centers, and a community garden to assist many urban and African-American women.

 

 

LCT Tenet 4: Environment. Attributes within a community (eg, lack of transportation) can either directly (eg, air pollution) or indirectly (eg, education) modify the expression of disease or its treatment.

Environmental influences

Where women live is an independent risk factor for prematurity and infant mortality. Socioeconomic confounders including race, ethnicity and education have typically been employed when describing perinatal outcome.  However, more recent research is demonstrating that regardless of race, ethnicity, and education, women residing in certain communities or neighborhoods are at increased risk.14

While the reasons are complex and often not well understood, it doesn’t appear that all races are affected equally. It may take years of residing in the same community for health impacts to become evident. Many possible factors affect a woman’s health, such as drinking-water quality, air quality, lead exposure, sanitation, access to health care, and employment. These important influences vary by neighborhood and are known to impact prematurity.

Recognition of the importance of the environment and community hasn’t produced evidence-based practices to reduce infant mortality. Understanding the root causes of fetal and infant mortality requires a coalition of community leaders in health care, government, academia, and industry intent on improving health disparities.

The National Fetal Infant Mortality Review (FIMR) project, created by Dr. Ezra Davidson in his American College of Obstetricians and Gynecologists Presidential Initiative in 1990, is one such collaborative community-health care-focused project. During the past 2 decades, the program has expanded and has been adopted by many Healthy Start grantees under the Health Resources and Services Administration. The focus of FIMR is to understand causes of infant deaths. FIMR staff and community healthcare providers review detailed records coupled with in-depth interviews of surviving mothers to get a better understanding of specific details and events that contribute to infant deaths. This process identifies community risk factors such as chronic disease; mental health effects from social and economic insecurity; loss of functionality during motherhood due to mental health problems; obstacles to securing safe, healthy, and affordable housing; and consequences of no or inadequate health insurance.

Health behaviors are affected by each LCT tenet. This often results in multiple underlying disparities manifesting as health disparities. Depression, which is common among women, illustrates this multiplicity principle. Depression prevalence varies considerably by race, age, and socioeconomic status.

Maternal depression during pregnancy and infancy is linked to prematurity, low birth weight, and other adverse birth outcomes.15 Prenatal depression is also associated with early breastfeeding cessation and newborn crying, fussiness, and inconsolability, which make it difficult for a parent to provide nurturing care.16 Depressed mothers are also more likely to report IPV and substance abuse.17 There is also evidence suggesting that both women and men who suffer from depression have common risk factors during their childhood and adolescence.18

Women living in poverty who report severe depression are 8 times more likely to report physical abuse within the previous 2 years than are nondepressed women living in poverty, 2.5 times more likely to report recent binge drinking, and less likely to be living with the father of their child or children (41% vs. 60%).18 African-American women already are at a higher risk of adverse birth outcomes and IPV, which is also associated with significantly higher rates of depression and suicide attempts as well as use of tobacco, alcohol, and illicit drugs.18

 

 

Summary

The implications of chronic risk factors on pregnancy outcome and disease expression are striking. The traditional medical model has often focused on individual health knowledge and access to the healthcare system to mitigate specific risk factors. But LCT directs attention “upstream,” to neighborhood conditions, community infrastructure, and social inequalities. Few good programs applying LCT exist, but we believe there are seeds of hope in those programs that employ LCT. Increasing knowledge, skills, and resources will translate into healthier babies and healthier communities.

References

1. Behrman RE, Butler AS, eds. Preterm Birth: Causes, Consequences, and Prevention. Washington, DC: National Academies Press; 2007.

2. Lu MC, Kotelchuck M, Hogan V, Jones L, Jones CP, Halfon N. A 12-point plan. Closing the black-white gap in birth outcomes: a lifecourse health development approach. Ethn Dis. 2010;20(1 Suppl 2):S62-76.

3. National Center for Injury Prevention and Control. Costs of Intimate Partner Violence Against Women in the United States. Atlanta, GA: Centers for Disease Control and Prevention; 2003.

4. Tjaden P, Thoennes N. Extent, Nature, and Consequences of Intimate Partner Violence: Findings from the National Violence Against Women Survey. Washington, DC: National Institute of Justice and the Centers for Disease Control and Prevention; 2000.

5. Parker B, McFarlane J, Soeken K, Silva C, Reel S. Testing an intervention to prevent further abuse to pregnant women. Res Nurs Health. 1999;22(1):59–66.

6. Kiely M, El-Mohandes AA, El-Khorazaty MN, Blake SM, Gantz MG. An integrated intervention to reduce intimate partner violence in pregnancy. Obstet Gynecol. 2010;115:273–283.

7. Centers for Disease Control and Prevention Office of Surveillance, Epidemiology, and Laboratory Services. Behavioral Risk Factor Surveillance System Prevalence and Trends Data. http://apps.nccd.cdc.gov/brfss/. Accessed June 12, 2012.

8. Hill KG, Hawkins JD, Catalano RF, Abbott RD, Guo J. Family influences on the risk of daily smoking initiation. J Adolesc Health. 2005;37(3):202-210.

9. Jones JM. Smoking habits stable; most would like to quit. July 18, 2006. http://www.gallup.com/poll/23791/smoking-habits-stable-most-wouldlike-quit.aspx. Accessed June 12, 2012.

10. Chen X, Stanton B, Shankaran S, Li X. Age of smoking onset as a predictor of smoking cessation during pregnancy. Am J Health Behav. 2006;30(3):247-258.

11. Malarcher A, Dube S, Shaw L, Babb S, Kaufmann R. Quitting smoking among adults-United States, 2001–2010. MMWR. 2011;60(44):1513-1519.

12. Chu SY, Kim SY, Bish CL. Prepregnancy obesity prevalence in the United States, 2004–2005. Matern Child Health J. 2009;13:614–620.

13. Finkelstein EA, Trogdon JG, Cohen JW, Dietz W. Annual medical spending attributable to obesity: payer- and service-specific estimates. Health Affairs. 2009;28(5):w822-w831.

14. Collins JW Jr, Wambach J, David RJ, Rankin KM. Women’s lifelong exposure to neighborhood poverty and low birth weight: a population-based study. Matern Child Health J. 2009;13:326–333.

15. England MJ, Sim LJ, eds. Depression in Parents, Parenting, and Children: Opportunities to Improve Identification, Treatment, and Prevention. Washington, DC: National Academies Press; 2009.

16. Vericker T, Macomber J, Golden O. Infants of Depressed Mothers Living in Poverty. Washington, DC: The Urban Institute; 2010.

17. Green KM, Fothergill KE, Robertson JA, Zebrak KA, Banda DR, Ensminger ME. Early life predictors of adult depression in a community cohort of urban African Americans. J Urban Health. 2013; 90(1):101–115.

18. Pickett KE, Collins JW Jr, Masi CM, Wilkinson RG The effects of racial density and income incongruity on pregnancy outcomes. Soc Sci Med. 205;60(10):2229–2238.