Dwelling Disparities: How Poor Housing Leads to Poor Health
More recently, the field has begun to take an even wider-angle view, as investigators
have begun using innovative new tools and approaches to explore the multifaceted
interrelationships between the built environment and population-level health
outcomes. It has become increasingly clear that the built environment not only
directly impacts our health, but also factors in less direct, complex ways
into the health of individuals residing in single-family homes, housing projects,
blocks, neighborhoods, and entire cities.
Low-income and/or ethnic minority communities--already burdened with greater
rates of disease, limited access to health care, and other health disparities--are
also the populations living with the worst built environment conditions. Studies
have shown that negative aspects of the built environment tend to interact
with and magnify health disparities, compounding already distressing conditions.
Elucidating the associations between the built environment and health disparities
has proven to be an enormous challenge to the scientific community, requiring
the development of new research paradigms, hypotheses, and methodologies. Traditional
studies have often lumped many important components of the built environment
into a blanket socioeconomic status variable. But this approach makes it nearly
impossible to tease out specific housing and community characteristics related
to disease. So, although the traditional tools of environmental health science
are still an important part of the mix, research endeavors in this area are
now incorporating aspects of sociology, psychology, demography, urban planning,
and architecture. Just as significantly, research efforts are reaching beyond
the boundaries of the scientific community, embracing rapid translation of
research into effective intervention and active collaboration with community
members as central concepts in their research protocols.
![Poor Apartment](image/foc-1.jpg) |
Home, bitter home? Tradition holds that home is
a haven, where people are protected and nurtured. For many, however,
home is a health hazard when factors such as poverty, environmental contamination,
and poor design combine to cause or exacerbate disease.
image: Alvaro Leiva/Panos Pictures
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Space: The Data Frontier
Spatial analysis is one of the new tools being applied in attempts to quantify
the relationship between health disparities and the built environment. One
spatial analysis tool, geographic information system (GIS) technology, has
long been in use in other areas such as city planning, demography, and epidemiology,
but is now allowing environmental and public health researchers to characterize
local environments at finely resolved geographic scales. More complete, accurate,
and comprehensive geocoded data on resources within communities are becoming
increasingly available from a growing number of sources such as governmental
agencies, law enforcement agencies, and marketing researchers. This allows
researchers studying the built environment to look at communities in new ways.
“The use of GIS technology allows researchers to look at the density
and proximity of goods, services, and community resources such as parks, youth
clubs, fast food outlets, convenience stores, and other factors that might
enhance or hinder health, in relationship to where people live and work,” says
Marilyn Winkleby, an associate professor of medicine at the Stanford Prevention
Research Center. “GIS provides the technology to spatially display, synthesize,
and analyze data--it creates a dynamic visual understanding of people, places,
and health.”
![Poor Houses: Chart](image/chart2-2.jpg) |
New tech on the block. GIS technology can help public
health officials pinpoint the worst environmental health hazards on a
house-by-house basis. Here, researchers mapped expected lead exposures
in Durham, North Carolina.
image: Children’s Environmental Health Initiative; inset: Chris
Reuther/EHP
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As part of a larger project examining neighborhood-level influences on mortality
from all causes, Winkleby and her colleagues are preparing to publish results
from two studies using GIS to link survey data with other information such
as census data, health records, and site visits. Both studies suggest pathways
by which disparities in the built environment can be related to disparities
in health.
The first study showed that, of 82 neighborhoods studied in four northern/central
California cities, the most deprived neighborhoods contained more places that
sold alcohol than the least deprived neighborhoods, despite the fact that residents
of the higher-SES neighborhoods were the most likely to be heavy drinkers.
Winkleby cites this disproportionate clustering in low-income neighborhoods--with
its documented sequelae of greater injuries and violence due to increased rates
of youth drinking and driving, assault, and car crashes--as one example of
why it’s important to examine the built environment in addition to individual
risk factors when studying health disparities.
Interestingly, the other study found that another characteristic of the physical
environment in the deprived neighborhoods influenced an individual risk factor. “Higher
convenience store concentrations--whether measured by density, distance, or
number of convenience stores within a one-mile radius of participants’ households--are
significantly associated with higher levels of individual smoking,” says
Winkleby.
Marie Lynn Miranda, director of the Children’s Environmental Health
Initiative (CEHI) at Duke University, says the use of spatial analysis allows
her center to more effectively quantify associations between the built environment
and health outcomes. “You can create variables of interest and structure
them according to what people tell you is the space of interest to them [such
as individual homes or unique neighborhoods],” she says. In contrast,
earlier studies often used traditional county, zip code, or census tract boundaries,
which people often don’t pay attention to as they go about the business
of their lives. Customizing study spaces “allows us to create and structure
and understand data and influences in a way that is more directly linked with
how people live their lives,” Miranda says.
Miranda’s research focuses on identifying interventions that will prevent
harmful environmental exposures in children, rather than mitigating existing
exposures that may have already affected children. Among several CEHI programs
currently in progress, the farthest along is an initiative to prevent childhood
lead exposure called Mapping for Prevention. The group has created GIS-based
lead exposure maps for 36 North Carolina counties and several other sites around
the country using census data, blood lead screening data, and county tax assessor
data to identify high-risk areas for lead poisoning. “The notion here
is to try to figure out the places that are likely to [contribute] to elevated
blood lead levels in children,” says Miranda, “and go in there
and do something about the housing stock before a child gets lead-poisoned.”
Once an exposure map has been developed, the researchers work with local
health departments to selectively and proactively screen children for lead
exposure, and to educate new parents who live in high-risk housing about how
to prevent their children from being exposed. They also help housing departments
identify ways to prioritize housing rehabilitation and lead abatement funding
to address the housing at greatest risk for lead poisoning.
Miranda is convinced that the spatial component is vital: “The work
we’re doing at this very highly resolved geographic scale is identifying
the risk levels at the individual tax parcel unit, and it provides us with
absolutely the most powerful tool to move from mitigation to prevention in
childhood lead exposure.” [For more information on GIS projects at Duke,
see “Mapping the Air in Public Schools,” p. A308 this issue.]
Drawing on Community Knowledge
One of the most significant recent developments in efforts to characterize
and ameliorate built environment conditions associated with health disparities
has been the growing movement toward community-based participatory research
(CBPR), which has been largely pioneered and supported by the NIEHS through
a variety of extramural grant programs. CBPR studies focus on gathering and
disseminating scientific knowledge about the interrelationships between the
physical and social environments and health, and to identify, evaluate, and
implement potential interventions--all with a distinct emphasis on active collaboration
with residents and other stakeholders within the communities being studied.
These multidisciplinary projects generally draw from many resources to arrive
at comprehensive understanding of the multifaceted dynamics at work in populations
suffering health outcome disparities--including negative aspects of the built
environment.
Detroit’s Healthy Environments Partnership is an example of a CBPR
endeavor. Academic researchers from the University of Michigan are working
directly with several community groups and health service providers to examine
the contributions of the physical and social environments to both ethnic and
socioeconomic disparities in risk factors for cardiovascular disease among
the adult population of Detroit. Part of the partnership’s wide-ranging
data collection involves assessing aspects of the built environment: housing
conditions, sidewalk conditions, land use, concentrations of airborne particulate
matter, and access to grocery stores, parks, and recreation areas.
Data have been gathered in three demographically diverse Detroit neighborhoods
that were initially selected because they were anticipated to vary in their
concentrations of airborne particulate matter. Air quality monitoring confirmed
this differential exposure. The researchers also surveyed neighborhood residents,
collected blood and saliva samples to assess physiological indicators of cardiovascular
risk and stress, and sent observers into the neighborhoods to evaluate the
built and social environments in each area.
Although the group is still analyzing the data, principal investigator Amy
Schulz, a research associate professor of health behavior and health education
at the University of Michigan School of Public Health, says they are seeing
trends suggestive of variations in both cardiovascular disease risk factors
and protective factors that play out for different racial and socioeconomic
groups across areas of the city. For example, they have noted variations in
dietary intakes of fruits and vegetables in population groups within the city,
and intend to analyze whether conditions in the built environments of the neighborhoods
can predict those variations.
Residents of the Detroit neighborhoods being studied have been involved at
all stages of the project, including helping to design the survey as well as
collect and analyze the data. “They are extremely knowledgeable about
the research that has been conducted,” says Schulz, “and understand
quite well the results that we are seeing and their implications for the community,
because they have been so integrally involved every step of the way.”
Also, says Schulz, community involvement contributes to a very rich analysis
whose results are more likely to lead to change. “It’s really important
for us to have good information about the impact of the built environment and
the social environment on health, but it’s clear that information alone
is not going to create change,” she says. “Engaging community members
in processes begins to build community mobilization efforts for change.”
![Barrio Chart](image/barrio1.jpg) |
Envisioning a healthier community. The Environmental
Health Coalition is working with Barrio Logan, a low-income Latino community
in San Diego, California, to map out a plan for future land uses to help
eradicate hazards and improve health.
image: Environmental Health Coalition
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Positive changes to the built environment that help reduce health disparities
can and do emerge from these partnerships. One such success story is San Diego’s
Environmental Health Coalition (EHC), a 25-year-old nonprofit organization,
funded largely by a grant from the U.S. Department of Housing and Urban Development
(HUD) through the Community Environmental Health Resource Center. This Washington,
DC, group helps community organizations develop their capacity to document
environmental health hazards in substandard housing and to pursue effective
organizing and advocacy strategies for corrective and preventive action [for
more information, see “Community Environmental Health Resource Center,” p.
A303 this issue]. The EHC works with university researchers, government agencies,
and community members to address toxic pollution, land use issues, and substandard
housing conditions in San Diego’s low-income communities of color.
Much of that effort has focused on the Barrio Logan, a low-income Latino
community plagued by poor air quality due to heavy diesel truck traffic from
a major regional freeway dissecting the community, and a troubling mix of industries
and residences in close proximity to one another. Armed with results of an
informal community health survey that showed disturbing levels of asthma and
other respiratory problems, the group convinced the California Air Resources
Board to begin monitoring air quality in the community. Since then, says EHC
research director Joy Williams, “We’ve gotten the city of San Diego
to agree to reroute truck traffic around the community and not through it--one
solution to the problem of diesel exhaust in the community. EHC and the community
are also working on changes to land use and zoning that will reduce the number
of warehouses and industries that generate diesel truck traffic in residential
areas.”
The air monitoring also led to a direct intervention to help a family in
distress. The group had identified a metal-plating shop on a residential street
in Barrio Logan as a potential hazard, and asked for air samples to be collected
in the immediate vicinity. Regulators previously had believed that an operation
of that size that was basically in compliance would not pose much of a hazard.
However, once they sampled the air, they found high levels of emissions such
as chromium-6, a highly toxic air pollutant, at the houses next door and across
the street, says Williams. It turned out that one family living next door had
a son with poorly controlled asthma. Ultimately, the metal-plating shop was
forced to close (although many businesses in similar circumstances simply relocate),
reportedly leading directly to dramatic improvements in the boy’s health.
The EHC continues to make such unhealthful mixed land uses a priority in its
activities.
Housing Developments
Housing is perhaps the ultimate nexus between the built environment and health
disparities, and it has been the focus of much recent research and intervention
activity looking at new approaches to old problems. The intimate connection
between housing and health has been well known for more than a century--Florence
Nightingale once wrote, “The connection between health and the dwelling
of the population is one of the most important that exists.” But today
there is renewed interest in discovering the complex pathways connecting housing
factors, neighborhood factors, social factors, adverse health outcomes, and
disproportionate disease burden in poor and ethnic minority communities--particularly
with respect to skyrocketing rates of chronic diseases such as asthma, obesity,
and diabetes.
That renewed interest is being manifested at the national and international
levels, as well as in the form of grassroots community action. In late 2004,
the World Health Organization convened its 2nd International Housing and Health
Symposium at Vilnius, Lithuania, a conference designed to review the existing
scientific evidence on housing and health relationships, and assess needs for
further research. In what may prove to be a development with wide-ranging global
impact, the symposium generated the Vilnius Declaration, in which 250 scientists
and officials representing 24 countries committed themselves “to taking
action to ensure that health and environmental dimensions are placed at the
core of all housing policies (from housing construction and rehabilitation
plans, programmes and policies to the use of adequate building materials) and
that healthy conditions are ensured and maintained in the existing housing
stock.”
![Roaches](image/roaches.jpg) |
It came from within. Some of the worst home health hazards,
such as the black mold crawling across the ceiling of an apartment (left)
and the cockroach droppings blanketing the floor behind a refrigerator
(below), arise inside homes that are poorly maintained or designed. Indoor
mold and cockroach antigens have both been associated with worsened asthma
and other adverse health effects.
images: Samuel Arbes/NIEHS
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In January 2005, indoor environmental quality took center stage at the Surgeon
General’s Workshop on Healthy Indoor Environment. The two-day gathering
of more than 300 experts from government, academia, the building sciences industry,
and public interest groups focused on increasing attention to the issue of
indoor air pollution, with the surgeon general and other participants calling
for action to improve the health of Americans by improving indoor environments.
At the local level, two of the many CBPR projects in progress around the
nation demonstrate the multifaceted, collaborative approach being taken toward
not only characterizing housing and health pathways, but designing, implementing,
and evaluating interventions as well. Both have come about in response to the
high prevalence of asthma in low-income urban communities, with a special focus
on improving the health and housing conditions of public housing residents.
Boston’s Healthy Public Housing Initiative (HPHI) is a collaboration
among public housing tenants’ right groups, the Committee for Boston
Public Housing, the Peregrine Energy Group, and several area universities and
city agencies. The collaboration has produced guidance for builders, architects,
and others on ways to make both new construction and existing housing healthier.
Participants are currently engaged in a four-year project to assess the effectiveness
of HPHI asthma intervention programs in three public housing developments.
The interventions include installation of air filters, purchase of new mattresses,
heavy-duty cleaning, integrated pest management, family education on controlling
asthma triggers, and installation of building systems upgrades and modifications.
The group published a study in the 7 December 2004 edition of the online
journal Environmental Health: A Global Access Science Source reporting
the results of a detailed baseline evaluation of 78 asthmatic children living
in the three public housing developments. Among other findings, the study showed
that many of the children, although they had access to primary care physicians,
were not receiving care according to professional asthma management guidelines,
which include recommended medications, monitoring practices and equipment,
and other measures. Also, exposure to violence, which has been related to exacerbation
of asthma symptoms, was a significant problem. In one development where a series
of murders had taken place during the study period, 60% of the children were
never allowed outside to play.
Add those factors to substandard housing, high concentrations of local ambient
air pollution, and other negative aspects of neighborhood built environments,
and it starts to become clear why the prevalence and incidence of asthma has
risen so sharply and disproportionately among low-income minority urban children.
The study report concluded, “Given the elevated prevalence of multiple
risk factors, coordinated improvements in the social environment, the built
environment, and in medical management would likely yield the greatest health
benefits in this high-risk population.”
A CBPR project currently under way in Seattle known as the High Point Healthy
Homes and Community Project is taking full advantage of a unique opportunity
to simultaneously address built environment issues in the public housing context
and gain useful knowledge about how comprehensive interventions can be used
to improve the health and well-being of residents. The Seattle Housing Authority
is in the process of reconstructing its public housing stock, to replace old,
deteriorating structures with town homes. One of the sites being updated is
High Point, formerly a 716-unit development, which is now being rebuilt as
a 1,600-unit mixed-income community.
The High Point Healthy Homes and Community Project is taking a multilevel
approach to designing a public housing development to be a healthy, sustainable
community. Developers are thoughtfully addressing a range of considerations,
from design issues such as layout, walkability, and watershed protection, to
the use of construction materials and practices that enhance indoor environmental
quality. This project of the local public health department, housing authority,
social service providers, public housing residents, and the University of Washington,
with funding from the NIEHS and HUD, is paying particular attention to the
needs of families affected by asthma.
“At the individual housing unit level, we made an estimate of the number
of families living in High Point affected by asthma, and are now building specially
enhanced units which will minimize exposure to asthma triggers by improving
the indoor environmental quality,” says James Krieger, principal investigator
on the NIEHS-funded component of the project, who is an epidemiologist with
the Seattle-King County Department of Public Health and a clinical associate
professor of medicine and health services at the University of Washington.
(Tim Takaro, also at the University of Washington, led the HUD-funded component.)
Thirty-five “Breathe Easy” demonstration homes will feature hardwood
flooring (instead of carpeting, which can outgas and cause respiratory problems)
and enhanced ventilation systems, weatherization, and insulation to minimize
humidity and moisture intrusion, costing an additional 3-4%, or roughly $5,000,
more than the development’s standard units (which will also go well beyond building
code requirements in several specifications).
Researchers will follow the families for a year before they move into the
units to establish a baseline assessment of their asthma status, and then continue
to follow them for a year after they move into their new homes, which are currently
under construction (the first families are scheduled to move in in fall 2006). “This
will be one of the first studies designed as an intervention of people moving
into [better]-quality housing while having a health outcome that’s clearly
measurable like asthma, to see what the health impact is,” says Krieger.
The Seattle Housing Authority and its organizational partner, Neighborhood
House, have also actively sought residents’ input in the design of the
new community. It is slated to include walking paths and trails, mini-parks
and one larger park, a grocery store, a public library, and a community health
center, in hopes that these amenities will provide a built environment more
conducive to health and social interaction. A community-based education initiative
is also under way, using trained teams of community residents called project
action teams to teach their neighbors about basic principles of how to keep
their homes and community healthy.
Krieger says they will conduct before-and-after community surveys assessing
people’s physical activity, social cohesion, and other factors. “Hopefully,
we’ll be able to empirically test the whole notion that a change in the
built environment will change health behaviors and increase community cohesion
and social capital,” he says. “There’s limited empiric data
out there on that now.” [For information on another innovative Seattle
housing project, see “Growing Green Communities,” p. A300 this
issue.]
David Jacobs, a HUD housing expert, sees wide-ranging potential in projects
that quantify such benefits. “If we are able to fully value those types
of investments in houses that produce positive health outcomes,” he says, “then
we can end the cost-shifting that causes both higher medical bills and higher
housing costs. Right now, the benefits of health investments in housing or
communities are largely hidden, with avoidable--and usually much higher--costs
being absorbed by the medical care sector, after the harm has already been
done.”
The Search for Solutions, Large and Small
Public health and urban planning, sectors that once were closely aligned,
have drifted apart over the decades, evolving into professional specialties
with too few opportunities to collaborate and little mutual influence, some
say. Many practitioners seeking solutions to the festering problems of health
disparities and built environment inequities see reconnection of the two fields
as a critical goal.
Jason Corburn, codirector of the Center for Occupational and Environmental
Health at Hunter College of the City University of New York, strongly advocates
recoupling the fields so as to build health considerations into land use, zoning,
community design, and other urban planning decisions that to a large extent
shape the long-term nature of the built environment. “Too often we’re
quantifying housing quality or some aspect of the built environment,” says
Corburn, “but we’re not looking historically and at the present
time at how these urban planning and land use decisions are being made--who’s
involved, what are the processes, who has access to the information. Without
that kind of political analysis of the public decision making behind it, I
think we’re missing a big piece of the built environment-health disparities
puzzle.”
Corburn has helped initiate and manage the development of a health impact
assessment process in San Francisco, which is rezoning several neighborhoods
in its Mission District. Corburn is working with the city’s public health
department and a group of nearly 40 stakeholders including tenants’ rights
organizations, business owners, and other community organizations. Their mission
is first to define the community’s ideas of the physical and social characteristics
of a healthy neighborhood, and then to construct a plan to incorporate those
elements as distinct goals of the rezoning process. “The health impact
assessment process in San Francisco is an experiment,” Corburn says, “but
I think it’s very promising. This kind of approach holds the potential
to reconstruct the boundaries of environmental health.”
![Roaches](image/drawin.jpg) |
Making houses into healthy homes. The High Point Healthy
Homes and Community Project in Seattle is employing a new paradigm for
public housing: design with health and sustainability in mind.
image: Seattle Housing Authority
|
Prevention Institute, a nonprofit group based in Oakland, California, works
with governments, communities, and organizations to establish prevention-oriented
health programs and policies. This institute is actively promoting increased
participation by public health practitioners in the built environment decision-making
process. To help foster greater understanding of the potential role public
health can play in improving health outcomes and reducing disparities by altering
the built environment, the group recently released a report, The Built Environment
and Health: 11 Profiles of Neighborhood Transformation, that highlights
local success stories across the country. The profiles include inner-city yard
lead abatement efforts in Boston, separate successful drives to close nuisance
liquor stores in south Los Angeles and open a grocery store in a deprived community
in Rochester, New York, and programs that have brought amenities such as jogging
paths, bike and walking trails, mural arts, and community gardens to other
municipalities. All of the interventions have involved collaborations among
community groups, local governments, and public health officials, and have
been aimed at reducing health disparities and improving the health of residents
of low-income communities.
One of the Prevention Institute’s projects to help communities address
health disparities is called THRIVE (Community Tool for Health and Resilience
in Vulnerable Environments). THRIVE is a toolkit designed to aid communities
in comprehensively assessing their conditions along a scale of risk to resiliency.
Executive director Larry Cohen illustrates the concept: “When we think
about risk, a street that does not have sidewalks or a separate place for bicyclists
is going to be far more dangerous than what we call a ‘complete street,’ which
functions for public transportation, for automobiles, for pedestrians, and
for bicyclists. Obviously, the first street is going to promote risk, with
far more likelihood of automobile crashes and air quality health-related issues,
and the second is going to promote resiliency, with more opportunities for
physical activity. So a risk can be ameliorated and create a community which
will be more resilient.”
The THRIVE toolkit describes 20 community factors within four interrelated
clusters: built environment, social capital (which includes societal factors
such as social cohesion and trust, civic engagement and participation, and
broadly shared beliefs and standards of behavior), services and institutions,
and structural factors, with a depiction of risk and resilience for each factor. “This
is about looking broadly at the community and creating environments in communities
where people want to live, where they can be healthy and safe,” says
program manager Manal Aboelata. This can have tremendous impact on not just
physical health but also mental health. The toolkit has been successfully pilot-tested
in both rural and urban communities, and is currently awaiting final approval
from federal funding agencies prior to being available nationally.
A Concrete Future?
Can this new paradigm within the environmental health sciences--with its
multidisciplinary, systems-level approach to interactions between the built
environment and health disparities--actually help to solve some of these long-standing,
large-scale problems? Even with the latest scientific knowledge and the enthusiastic
participation of a multiplicity of stakeholders, can profound, lasting change
realistically be expected to follow? Although there are many encouraging trends,
the challenges are formidable and complex, and observers active in the field
understand that their campaign will be long, with no assurance of victory.
Carlos Mendes de Leon, an epidemiologist at Rush University Medical Center
in Chicago, is investigating the biological and environmental mechanisms by
which socioeconomic deprivation leads to disability in older people. His comments
on the potential for broad improvements at the societal scale are representative
of those heard from many researchers who are determined to soldier on: “At
this moment, it’s hard to see this kind of knowledge and understanding
of the built environment and health disparities having very concrete ramifications
for public policy and medical interventions,” he says.
“But at the same time,” he adds, “we still have to build
up the knowledge base so that when conditions change in the broader political
sphere, we can point to concrete evidence and concrete strategies that may
make an effect.”
Yet there have been many important achievements that demonstrate the potential
power of these ideas. For example, the number of both lead-poisoned children
and houses with lead-based paint have been reduced over the past decade thanks
to concerted action by policy makers and community members. Many diseases that
still plague the developing world, such as typhoid and cholera, have been largely
eradicated in the United States due in part to improvements in housing density,
ventilation, and reliable community water supplies. Learning from these examples
should be a first step toward restoring the connections between environmental
health, housing, urban planning, and the built environment so that many of
the diseases that still plague us today can also be wiped from our lives.
Ernie Hood |