Adolescent HIV Prevention: The Next Generation

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Adolescent HIV Prevention: The Next Generation Powered By Docstoc
					     Racial/Ethnic Disparities in Sexually
Transmitted Infections among Adolescents and
      Young Adults in the United States

        Jonathan M. Ellen, MD
        Professor of Pediatrics
   Johns Hopkins School of Medicine
                 Outline

• Epidemiology
  – STI
  – Behavioral
  – Social
• Implication
          Gonorrhea — Rates by race/ethnicity: United States, 1998–2007


Rate (per 100,000 population)
       900


       720


       540                      American Indian/AK Native
                                Asian/Pacific Islander
                                Black
                                Hispanic
       360                      White



       180


         0

               1998        99       2000          01        02   03   04   05   06   07
           Chlamydia — Rates by race/ethnicity: United States, 1998–2007

Rate (per 100,000 population)
    1700
                                American Indian/AK Native
                                Asian/Pacific Islander
                                Black
    1360                        Hispanic
                                White

    1020


     680


     340


       0

             1998         99        2000          01        02   03   04   05   06   07
       Chlamydia — Prevalence by age group and race/ethnicity reported
                                    from
                       a national survey, 1999–2002
Prevalence
 16
                                                                            Non-Hispanic White
                                                                            Non-Hispanic Black
 12                                                                         Mexican-American




  8


  4


  0
                       14-19                                        20-29              30-39


         Note: Error bars indicate 95% confidence intervals.
         SOURCE: National Health and Nutrition Examination Survey
         Ann Intern Med. 2007 Jul 17;147(2):89-96.
      Primary and secondary syphilis — Rates among 15- to 19-year-old males by
                      race/ethnicity: United States, 1998–2007


Rate (per 100,000 population)
        20
                                            American Indian/AK Native
                                            Asian/Pacific Islander
                                            Black
        16                                  Hispanic
                                            White

        12


         8


         4


         0

               1998        99   2000   01   02         03           04   05   06   07
     Primary and secondary syphilis — Rates among 15- to 19-year-old females by
                      race/ethnicity: United States, 1998–2007


Rate (per 100,000 population)
        25
                                                        American Indian/AK Native
                                                        Asian/Pacific Islander
                                                        Black
        20                                              Hispanic
                                                        White

        15


        10


         5


         0

               1998        99   2000   01   02   03     04          05              06   07
                      Add Health
• Longitudinal study of health status of youth
• Three waves of data collection
   – 1994-5,1996,2001-2002
• Primary sampling unit was school
   – Representative of region, urban/rural, school type, ethnicity,
     and school size
• Wave III participants (n=14322) tested with Orasure
   – 18-26 years old
   – 51% male
   – 68% white, 12% Latino, and 16% African American
 Estimated HIV Prevalence Among 18-25 years
              old, US 2001-2002

                          Cases   Rates per 1000

Gender

  Male                    11954   1.06

  Female                  9432    0.87

Race/Ethnicity

  Black                   17275   4.92

  Other                   4112    0.22

Total                     21387   0.97


Morris et al, AJPH 2005
        Percentage of High School Students Who Ever Had
       Sexual Intercourse, by Sex* and Race/Ethnicity,** 2007

              100



              80
                                                           66.5

              60
    Percent




                    47.8                    49.8                    52.0
                                 45.9              43.7
              40



              20



               0
                    Total       Female      Male   White   Black   Hispanic




National Youth Risk Behavior Survey, 2007
   Percentage of High School Students Who Were Currently
      Sexually Active,* by Sex and Race/Ethnicity,** 2007
              100



              80



              60
    Percent




                                                           46.0

              40    35.0         35.6                               37.4
                                            34.3   32.9


              20



               0
                    Total       Female      Male   White   Black   Hispanic




National Youth Risk Behavior Survey, 2007
  Percentage of High School Students Who Used a Condom
       During Last Sexual Intercourse,* by Sex** and
                   Race/Ethnicity,*** 2007
              100



              80
                                            68.5           67.3
                    61.5                                            61.4
                                                   59.7
              60                 54.9
    Percent




              40



              20



               0
                    Total       Female      Male   White   Black   Hispanic




National Youth Risk Behavior Survey, 2007
     Disparities and Behavior
• To determine whether racial/ethnic
  differences in SES and personal
  behaviors explain differences in
  self-report of an STI
              Methods
• 1992 Youth Risk Behavior Survey
  supplement to the National Health
  Interview Survey (YRBS-NHIS)
• Representative sample of households in
  the U.S. with at least one adolescent
• Included in- and out-of-school youth
• 5,189 sexually active adolescents
  14-21 years
              Measures
• Socio -demographic and -economic
  factors: age, gender, race/ethnicity,
  school status, region, income, and
  parental education
• Sexual behaviors: age at sexual debut,
  number of sex partners lifetime and in
  last 3 months, condom use last sex, and
  alcohol/drug use last sex
• Self-reported history of an STI
Relative Risks for STIs by Race/Ethnicity
            Odds Ratio (95%CI)

 White                  1.32 (0.61, 2.85)
 African-American       3.16 (1.44, 6.91)*
 Hispanic               0.99 (0.40, 2.25)
 Other (reference)      1.00

 *p<0.001
Relative Risks for STIs by Race/Ethnicity,
 Adjusted for SES and Sexual Behavior
            Odds Ratio (95%CI)

White                   1.11 (0.49, 1.69)
African-American        3.66 (1.55, 8.67)*
Hispanic                1.12 (0.46, 2.72)
Other (reference)       1.00

*p<0.001
100,000
 PERCENT BLACK PER CENSUS BLOCK GROUP
            Baltimore City, 2000




Percent Black
 98 to 100   (164)
 86 to 98    (185)
 29 to 86    (183)
  0 to 29    (178)




                     0     2.5          5
                           miles
     Structures and Disparities

• Structural factors operate outside the
  individual
• Residential segregation is structural
• Residential segregation creates
  disparities
  – Creates separate groups
  – Creates isolation and unequal
    opportunities
• Disparities in STIs are structural
       Effects of Segregation



Poor White   Poor Black     Middle        Middle
                          Class Black   Class White
        Effects of Segregation



Poor White   Poor Black     Middle        Middle
                          Class Black   Class White
              Laumann and Youm (1999)
             ε=0 (assort)       ε=.65 (obs)       ε=1 (random)
               L     H            L     H               L   H
Blacks




         L     .59 0        L     .45 .14          L    .35 .24
         H     0     .41    H     .14 .27          H    .24 .17

             ε=0 (assort)       ε=.58 (obs)       ε=1 (random)
                L     H           L     H           L    H
Whites




         L      .78 0       L     .68 .10     L     .61 .17
         H      0     .22   H     .10 .12     H     .17 .05
     Bayview Networks Study
       San Francisco, CA
• Enrolled household sample of 14-19
  year olds and 1-2 best friends (n=300)
• Enrolled their sex partners and their sex
  partners’ sex partners (~60%)
• Interviewed all participants about sexual
  and drug behaviors
• Linked data together to map networks
              Adolescent Sex Networks
                       Index
    Men



 Risky Men



   Women


   Risky
   Women




Sex Partner



   Friend
Adolescent Sex Networks
  High Risk Subgroups
Adolescent Sex Networks
  Low Risk Subgroup
100,000
            NIAAH Study

• To determine whether CBG gonorrhea
  prevalence is associated with individual
  diagnosis of an STI, adjusting for known
  individual level risk factors.
             Study Design
• Longitudinal household study conducted
  from April 2004 to April 2007 (PI: Ellen)
  – Phase one: Qualitative interviews
    and pilot study of measures
  – Phase two: Baseline household survey
    and biologic testing
  – Phase three: One year follow-up
    telephone survey
             Target Population

•   15-24 year olds
•   English-speaking
•   Sexually active
•   Resident
    We estimate that the target population
    comprised approximately 58,299 persons
    living in the 486 census block groups in 2005.
            Sampling Strategy –
         Three stage cluster design
• First stage – census block group
  selection
  – Criteria for inclusion:
     • gonorrhea rate greater than the 25th percentile
       (533 or 75% )
     • greater than or equal to 35 estimated eligible
       households
       (486 or 91%)
  – 65 cbgs were then selected using a probability
    proportional size, stratified and systematic
    sampling strategy (Raudenbush 1997)
           Sampling Strategy
• Second stage – household selection
  – Sampling frame comprised a total of
    27,194 addresses from 3 commercially
    available lists
  – Non-linear optimization used to select
    households in the 12 strata (Chong and Zak
   1996)
  – Resulting in 13,873 selected households
    in order to enroll 10 participants from
    each census block group (Raudenbush
   1997)
          Sampling Strategy
• Third stage – individual selection
  – Enumeration to determine age-
    eligibility via telephone and in-person
     • If more than one eligible 15-24 year old, one
       was randomly selected for screening
               Procedures
• Screening to determine sexual activity,
  residence at the selected address and
  English-speaking
• Informed consent, Parental informed
  consent/Adolescent assent
• Audio computer-assisted self-interview
  (audio-CASI)
• Biologic samples collected
  for chlamydia and gonorrhea testing
                   Measures
• Individual level outcome
   – current chlamydia and/or gonorrhea infection
• Neighborhood level variable of interest
   – Average gonorrhea rate from 2004-2005 per 15-
     49 year olds per 100,000 per census block group
• Individual level control variables
   – Demographic – age, gender, maternal education
   – Behavioral – condom use last sex,
     number of sex partner in the last 90 days
         Statistical Analysis

• Series of multilevel nonlinear models
  – Random-effects analysis of variance
    (ANOVA)
  – Means as outcomes regression (MAOR)
  – Analysis of covariance (ANCOVA)
  – Full model with gonorrhea rate
    adjusting for individual level demographic
    and behavioral variables
           Eligible Households
• Of the 27,194 addresses in the second stage
  sampling frame, 50% (13,699) were fielded and of
  these, 74% (10,173) households were successfully
  screened.

• 2 of the 65 census block groups were found to be
  comprised exclusively of retirement communities and
  were excluded.

• Among households enumerated, 12% (1,270) had at
  least one English speaking person between the ages
  of 15 and 24.
             Response Rate
• Screenings for sexual activity were attempted
  in 77% (981) of the age-eligible households
  with a completion rate of 70% (682) yielding a
  response rate to the interview among those
  selected of 68.0%.

• This yielded an overall interview response
  rate of 51% (599) and overall interview with a
  biologic specimen response rate of 50%
  (589).
             Characteristics (N=556)
Age, mean (SD)                                   19.27 (2.71)
Female                                             342 (62)
Black, non-Hispanic                                476 (86)
Maternal education: ≤High school degree/GED        361 (64)
No condom use last sex                             226 (41)
Sex partners, past 90 days                0-1     401 (72)
                                           2-3     119 (22)
                                           >4       36 (6)
Current chlamydia and/or gonorrhea infection        37 (7)
Average gonorrhea rate per census block          1,379 (689)
group, mean (SD)
   Means-As-Outcomes Model

                                 OR      95% CI
Intercept                       0.06    0.04, 0.09
Gonorrhea rate, median split     3.16  1.32, 7.56
Tau                            0.09242     -

* p value < 0.05
             Final Adjusted Model
                                   AOR       95% CI
Intercept                           0.16    0.01, 2.50
Age                                 0.89    0.78, 1.00
Sex                        Male    Ref
                         Female    1.52*    0.71, 3.24
Maternal education                 0.58*    0.36, 0.93
Number of sex partners, past 30    1.53*    1.17, 2.01
days
Condom use last sex                1.50     0.70, 3.22
Gonorrhea rate, median split        2.59*   1.10, 6.13
Tau                               0.01674       -
 * p value < 0.05
               Cohen et al*
• Assessed housing and school conditions of
  55 census block groups
• Developed “broken window” index
• Compared census measures, liquor stores, &
  broken window index with gonorrhea rates
• Liquor stores and broken window index
  explained more variance in gonorrhea rates
  than did a poverty index

*AJPH 2000;90:230-236
 “Broken Windows” and Gonorrhea:
      New Orleans, 1994-1996
Poverty   Broken    Sample   Gonorrhea
Group     Windows   Size     Rate
Low       Low       25       27
Low       High      4        32

High      Low       10       25

High      High      16       52
     Bayview Networks Study
       San Francisco, CA
• Enrolled household sample of 14-19
  year olds and 1-2 best friends (n=300)
• Enrolled their sex partners and their sex
  partners’ sex partners (~60%)
• Interviewed all participants about sexual
  and drug behaviors
• Linked data together to map networks
           Network position
Position                Individual   Partner

1                           1          1


2                           1          ?


3                           1          >1



4                          >1         1/?



5                          >1          >1
         Logistic regression results
                                          OR* [95%CI]

                                           Reference


                                          2.8 [0.9- 9.4]


                                          4.3 [1.4-13.5]



                                          6.6 [2.1-20.9]



                                          6.4 [2.1-19.0]

* Adjusted for age, gender, condom use, study wave and participant type
               Exposures
• Census block groups (CBGs)
• 2000 US Census
  – Percent of persons below poverty
  – Percent employed
  – Gender ratio (M/F)
  – Percent female-headed households
Bivariate associations
                    %
                  100

                   90

  %                80
100

 90
                   70

 80                60
 70                50
 60
                   40
 50
                   30
 40

 30                20

 20                10
 10
                    0
  0                      L         M         H          L      M    H          L   M   H     L
      Low   Mod   High       Low       Mod       High       Poverty tertiles
                             Poverty                    Employment        Female Head        Se
        Baseline               Follow-up                    Study wave

       Network risk                    Network
                                       1                risk
                                                        2           3      Low             Mod
     Logistic regression results

Odds of being in low vs. high or moderate risk network
position

                           Adjusted for age and sex*
Poverty (ref.=Low)
  Moderate                      0.47 (0.21-1.07)
  High                          0.15 (0.05-0.46)




*Adjusted for correlation between individuals in same CBG
  Structural Determinants of HIV

• Aspects of the environment that act
  outside of the control of an individual
  that impede or facilitate an individual’s
  ability to prevent HIV transmission or
  acquisition.
    Connect to Protect® (C2P)
• Initiative of the Adolescent HIV Prevention
  Trials Network (ATN)
  – 6 years
  – 3 phases
  – 13 high risk domestic urban communities
• Objectives
  – To determine whether community mobilization can
    lead to structural change
  – To determine whether structural change can lead
    to decreased risk for transmission
                      Ultimate Outcome: HIV Transmission




                  Number of
                   partners



               Partner selection
                  (high-risk
                 vs. low-risk)



 Structural    Multiple partners       Reduce the chances       Reduce
                                        for people to have     incidence
Determinants   at the same time
                (concurrency)           infected partners         and
                                                              prevalence
                                                                of HIV

                   Condoms/
                 clean needles




               STI Co-Infection



                                      Reduce the chances
                  Viral load          of transmitting virus
                                          if a partner is
                                             infected
   C2P Puerto Rico at a Glance
• Focused on substance users in San Juan, PR
• Started strategic planning March 2006
• Types of C2P Partners
  – Social & health services (i.e. Iniciativa Communitaria, Lucha
    contra el SIDA)
  – Government (i.e., health dept)
  – Faith-based HIV prevention (i.e. Perla de Gran Precio)
  – Education (i.e., Pharmacy Student Division of UPPR)
            Sample Action Plan
• Structural Change Objective
   – The Risk Reduction Alliance will implement a needle
     exchange and condom distribution program in one
     community pharmacy located in a high incidence of
     substance abuse area in San Juan Municipality.
• Action Steps
   – Met with students from the School of Pharmacy
   – Garnered support from the Harm Reduction Coalition for the
     provision of syringes
   – Garnered support from Tecnochem, a company that gathers
     biomedical wastes, to obtain the services free of charge.
            Sample Action Plan
• Structural Change Objective
   – Amend Law 81 to allow health professionals or
     representatives to offer HIV/STI prevention counseling to
     youth under 21 years of age without parental consent.
• Action Steps
   – Involved members of different community sectors to be part
     of this subcommittee.
   – Garnered support from the Secretary of Health’s HIV/AIDS
     Advisor
   – Public Hearing (Dec.07) provided data results to educate
     legislators on the impact of HIV among youth populations.
              Conclusion

• Changing structural risks for STIs and
  HIV is essential to reducing disparities
• Changes in structures result in broader
  coverage and greater sustainability
• Preliminary results show early
  successes

				
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