Spatial Inequities and Health Disparities among American Indians and Alaska Natives Tommi L. Gaines, DrPH January 26th, 2018 UCSD HIV & Global Health Round

2. Spatial Inequities and Health
Disparities among American Indians
and Alaska Natives
Tommi L. Gaines, DrPH
Assistant Professor
Department of Medicine
Division of Infectious Diseases and Global Public Health
Email: togaines@ucsd.ed
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3. Objective
Identify potential disparities in the geographic
accessibility to HIV testing and HIV medical care
for American Indian and Alaska Native (AI/AN)
population in San Diego County, California
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4. Outline
• Background
• HIV and AI/AN population
• Study Design
• Results
• Conclusion
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5. AI/AN population
• In 2010, 5.2 million people reported being
American Indian or Alaska Native alone or in
combination, representing 1.7% of the US
population
• Projected to grow to 8.6 million and comprise
2% of US population by 2050
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6. Tribal Diversity
• Highly heterogeneous group representing 565
federally recognized tribes
• In San Diego County there are 18 different federally
recognized American Indian reservations
– Different languages, cultures, beliefs, tribal governance
structures, population sizes
– United by history of colonization, oppression, racism,
alienation from culture traditions, and trauma
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7. Residential Distribution
• Majority of AI/AN do not live on a reservation
or tribal land
– In 1970, 38% of AI/AN lived in urban areas
– In 2010, 78% of AI/AN lived in urban areas
– Many AI/AN’s live in periphery of city centers, in
suburban and semi-rural areas but frequently
travel to reservations for family and ceremonies
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8. 7

9. Sociodemographic Composition
• Compared to overall U.S. Population :
– Younger (median age 29 vs. 37.2 years)
– Reside in a female-headed household (11.9% vs.
7.2%)
– Lower high school graduation rates (77% vs. 86% )
– Live below poverty level (28.4% vs. 15.3%)
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10. Invisible Minority in the HIV Epidemic
< 1% of estimated 39,513 HIV diagnoses in U.S.
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Source: cdc.gov

11. Why address HIV among AI/AN?
• AI/AN is a population at risk but have a low
national HIV burden
• AI/AN communities have called on the CDC to
improve the quality of HIV surveillance data that
can be used to inform public health action
• 2020 National HIV/AIDS Strategy
– Need to better characterize HIV among smaller
populations including AI/AN and focusing on places
with high concentrations of these populations
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12. AI/AN are Vulnerable to HIV Infection
• Nearly 1 out of 5 AI/AN are infected with HIV
but do not know it (compared to 13% of
general population)
– Approx. 20% of newly diagnosed cases are full
blown AIDS
– 55% AI/AN receiving prenatal care had not been
tested compared to 46% of pregnant women in
general population
• During 2010-2014, rates of HIV diagnoses
increased from 7.8 to 9.5 per 100,000 (+22%)
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13. STI Inequities among AI/AN
2nd highest rate of Chlamydia compared to other
racial/ethnicity groups in 2016
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Source: CDC.gov

14. STI Marker of Elevated HIV risk
The rate of gonorrhea among AI/AN (242.9 cases per
100,000) was 4.4 times the rate among Whites (55.7
cases per 100,000)
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Source: CDC.gov

15. Other Factors Linked to HIV risk
• Stigma and discrimination
• Confidentiality
• Distrust of Western medicine
• Alcohol and illicit drug use
• Lack of awareness of infection status
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16. HIV Care among AI/AN
• 77.5% AI/AN linked to medical care within 3 months of an HIV
diagnosis compared to 86.1% among White
• Compared to all HIV infected individuals, AI/AN least likely to
receive continuous HIV medical care (41% vs. 51.5%)
• AI/AN had the lowest HIV survival rate among all single
race/ethnic individuals living with HIV during 2008-2011 in the
U.S
• Geographic access to HIV services may be limited among
AI/AN
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17. Objective
Identify potential disparities in the geographic
accessibility to HIV testing and HIV medical care
for American Indian and Alaska Native (AI/AN)
population in San Diego County, California
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18. San Diego County HIV Epidemic
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19. 18

20. Ecological Analysis
• Create a Geographic Information System (GIS)
surveillance of HIV testing and medical care in San
Diego County
• Identify travel time to reach HIV services relative to
the AI/AN resident population
• Compare non-spatial characteristics (i.e.,
sociodemographics and clinic attributes) of
neighborhoods with very large numbers of AI/AN
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21. Unit of Analysis
• Census tracts in San Diego County (n=627)
• Population of interest:
– Census tracts with a high proportion of AI/AN
population relative to all other census tracts
– Census tracts with American Indian reservation
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22. Outcome
• Travel time to reach HIV services including HIV
testing and HIV medical care
• Online database: HIV.gov
– Address of all facilities providing HIV testing and
care that is supported by the Health Resources &
Service Administration (HRSA)
– Contacted facilities to inquire about hours of
operation and ability to refer individuals
diagnosed with HIV to provider within network
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23. Sociodemographic Comparison
• Insurance coverage
• Age
• Poverty
• Household vehicle ownership
• Education
• Medically underserved areas
– Areas or populations that lack access to primary
care services
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24. Spatial Analysis
• Network-based spatial analysis
– SANDAG: street-level spatial data
– Constructed a transportation network
– From the census tract centroid we estimated the
minimum travel time to reach the nearest HIV
testing or medical care facility
• Network analysis conducted in ArcGIS 10.3.1
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25. Statistical Analysis
• Bivariate analysis to compare
sociodemographic characteristics by AI/AN
population
– Wilcoxon rank sum test to assess statistical significance
• Logistic regression analysis
– Dichotomized travel time
• Long travel time (travel time at/above 90th percentile)
• STATA 14.1
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26. 25
Results

27. 26
Demographics
American Indian (AI)
Reservation
Median
(overall)
(n = 627)
No
(n = 612)
Yes
(n = 15)
Population size (overall) 4,769* 2,800* 4,727
AIAN population density per 1,000 residents 10.9* 58.5* 11.2
Uninsured 14.5% 16.8% 14.5%
Age
≤ 24 years old 33.3% 30.9% 33.2%
25 to 44 years old 28.3%* 20.3%* 28.2%
≥ 45 years old 37.1%* 48.0%* 37.4%
Living below FPL 12.2% 11.6% 12.1%
No vehicle in household 4.3%* 1.9%* 4.2%
Education (at least HS diploma) 19.4%* 24.6%* 19.7%
Medically Underserved Area (MUA) 14.5%* 40%* 15.2%
Table 1: County demographics by AI/AN population and
census tracts
*p<0.05

28. 27

29. 28
Clinic Characteristics
Near AI reservation
No
(n=612)
Yes
(n=15)
Free HIV test 45.1% 15.4%
Open M-F with Extended Hours 36.6% 7.7%
Open Saturday 38.0% 11.5%
HIV referral within health network 64.2% 43%
Table 2: Clinic characteristics offering HIV services stratified by
proximity to American Indian (AI) reservations

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Clinics near AI
reservations:
• Less likely to offer
free HIV testing
• Less likely to have
extended business
hours
• Less likely to offer
HIV care within the
clinics health care
network

31. 30
Census tracts
with a very high
AI/AN presence
(≥5.8%) are not
all located near
census tracts
with an AI
reservation

32. Table 3: Population size across different geographic areas with high
presence of AI/AN residents
• Compared to census tracts with lower AI/AN presence, census
tracts with a large AI/AN presence were more likely to have longer
travel time to reach
 HIV testing OR= 2.8; 95% CI = 1.14, 6.68
 HIV care OR = 3.61; 95% CI = 1.7, 7.5
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95th percentile of
AIAN presence
AI/AN
Reservation
Below
5.8%
(n=596)
At/Above
5.8%
(n=31)
No
(n=607)
Yes
(n=15)
Overall population size (median) 4,753 4,624 4,769 2,800
AI/AN population density per 1,000 residents 10.1 78.5 10.9 58.5
Travel time to HIV testing in minutes (median, IQR) 5 (3-8)* 7 (3-12)* 5 (3-8)* 16 (12-24)*
Travel time to HIV care in minutes (median, IQR) 10 (6-15) * 17 (7-30)* 10 (6-15)* 40 (34-64)*
*p<0.05

33. Conclusion
• Geographic location and the potential access to
HIV services is limited in places with a large
presence of AI/AN
• Longer travel time may pose a greater burden for
AI/AN to manage their health and health care
• Clinics near areas with large AIAN populations are
less likely to offer services that would make them
more accessible, beyond geographic proximity
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34. Limitations
• HIV.gov is not an exhaustive list of all HIV service
providers, private clinics underestimated
• Travel time may have been underestimated in
semi-rural and rural regions of county and
analysis did not account for travel time by public
transit
• Only examined aggregate associations; cannot
make inferences at individual-level
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35. Implications
• Where you live can make you more vulnerable
to HIV infection
– For AI/AN, inadequate access to HIV services could
lead to less HIV testing or treatment adherence
among people living with HIV
– Need for public health awareness campaigns on
HIV prevention and engagement in HIV care in
areas with large AI/AN presence
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36. Acknowledgements
• This research was supported by the UCSD
CFAR grant, P30 AI036214 and the National
Institute on Drug Abuse grant, K01DA034523
• Research Partners: Marta Jankowska and
Sanjay Mehta
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37. We must promote expert Indians
instead of Indian experts
Beverly Pigman
Navajo Nation
Institutional Review Board Chair
Thank you and Questions?
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