Social Determinants of Health and Birth Outcome Disparities

1
Social Determinants of Health and Birth Outcome
Disparities

• Gail C. Christopher, D.N.
• June 2007

2
Courage to Love Infant Mortality Commission

• 2005 2007
• Co-Chairs Reverend Dr. Ronald David Barbara
  Nelson, In partnership with UCLA UMICH.

3

• U.S. Ranks 28th
• African American rates were twice as high and
  rising.

4

• Focusing on prenatal care in our public health
  policy prescription for infant mortality
  disparities ignores the socioeconomic context in
  which women live, medicalizes a problem that is
  socially and historically complex, and thus
  contributes to the illusion that there is a
  medical policy bullet that can provide a
  comprehensive and efficacious solution
• Frisch Lantz 1999

5

• Disparities in health, education, employment, and
  wealth, along with persistent residential
  segregation, are vestiges of a long history of
  oppression and denial of fundamental human
  rights. The legacy of racial injustice shadows
  this nation and African American Communities in
  the form of persistent infant mortality
  disparities. True healing must emerge through
  acknowledgement, reconciliation, and amelioration
  of the inequalities that continue to
  disproportionately burden African Americans and
  other people of color
• Christopher, 2005

6
Black women are at increased risk for adverse
birth outcomes

• Ectopic pregnancy
• Spontaneous abortion
• Cesarean delivery

• Preterm birth
• Low birth weight
• Birth defects
• Infant death

• Maternal death from pregnancy-related
  complications

Reveiwed by S. Gennaro, Am J Obstet Gyneco 192,
S310, 2005
7
How Could Environmental Chemicals Contribute to
Disparities?

• Different exposures to environmental chemicals
• Different genetic susceptibility to environmental
  chemicals
• Different acquired modifications of
  susceptibility to environmental chemicals

Interactions
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Differences in Exposure

• The Center for Disease Control (CDC) conducts
  biomonitoring of US population exposure to
  environmental chemicals
• Measure chemicals or their metabolites in blood
  or urine of participants in the National Health
  Nutrition Examination Survey (NHANES)
• The Third Report on Human Exposure to
  Environmental Chamicals presents data on 148
  chemicals for years 2001-2002

(http//www.cdc.gov/exposurereport/)
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NHANES Results on Racial Differences in Exposure
Blacks have higher levels of certain chemicals or
their metabolites than Whites

• p,p-DDE (DDT metabolite)
• Phthalates (certain monoester metabolites)
• Organochlorine pesticides (2,5-dichlorophenol,
  2,4,6-trichlorophenol)

• Lead (urine)
• Mercury in blood but not urine
• Cotinine (nicotine metabolite)

10
Blood mercury is higher in Black women of
reproductive age compared with women of other
racial identities
NHANES 1999-2000 and 2001-2002
From Centers for Disease Control and Prevention.
Third National Report on Human Exposure to
Environmental Chemicals. Atlanta (GA) CDC, 2005.

• Among females aged 16-49 years, non-Hispanic
  Blacks had higher levels than non-Hispanic Whites
  and Mexican-American females.
• Racial differences not observed for urinary
  mercury.

11
2,4,6-Trichorophenol is higher in non-pregnant
Black women of reproductive age compared with
women of other racial identities
Analysis of NHANES data

• Use as a wood preservative was discontinued in
  1970s in USA
• Is a metabolite of the insecticide lindane, which
  is used as pharmaceutical treatment for lice
  scabies
• Measured in urine

Data analysis by L. Kobeissi and J. Meeker
12
Focus on Preterm Birth
From Martin et al., Births Final data for 2004.
National vital statistics reports, 55 (1). 2006.

• There has been a steady increase in preterm birth
  over the past two decades

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Environmental Justice Living with pollution

• Living near sources of air pollution increases
  risk of preterm birth
• Petroleum refinery plants (Lin et al., 2001 Yang
  et al., 2004)
• Petrochemical industrial complexes (Yang, Chang,
  et al., 2002 Yang, Chiu, et al., 2002)
• Industrial districts including petrochemical,
  petroleum, steel, and shipbuilding industries
  (Tsai et al., 2003)

http//www.demographia.com/db-fuji.htm
14
Living in regions with high sulfur dioxide and
particulate air pollution increases risk of
preterm birth

• Living near sulfur dioxide and particulate
  pollution sources
• Highways (Wilhelm and Ritz, 2003 Yang et al.,
• 2003 Ponce et al., 2005 Wilhelm and Ritz,
  2005)
• Coal-burning power plant (Mohorovic, 2004)
• Increased risk is concentration-dependent (Liu et
  al., 2003 Bobak, 2000 Xu et al., 1995)
• Not all studies found an association (Sagiv et
  al., 2005 Landgren, 1996)

http//www.fotosearch.com/GSH143/gs033008/
http//www.ens-newswire.com/ens/jun2002/200
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Minority women are more likely to live in areas
of high air pollution

• Minority populations are more likely to live in
  areas with higher air pollution in the USA
  (Brown, 1995 Silbergeld and Patrick, 2005)
• Pregnant women of minority race are more likely
  to live in areas of higher air pollution in the
  USA (Ponce et al., 2005 Woodruff et al., 2003)
• Black women living in areas of high
  traffic-related air pollution have an additional
  increased risk for delivering preterm (Ponce et
  al., 2005)