Associated With Prevalent Hepatitis C: Differences Among Young
Adult Injection Drug
Users in Lower and Upper Manhattan, New York
of Public Health 23
Diaz, MD, MPH, Don C.
Des Jarlais. PhD, David Vlahov. PhD. Theresa E. Perlis,
PhD, Vincent Edwards. Samuel R. Friedman. PhD. Russell
Rockwell, PhD, Donald Hoove1; PhD. Ian T Williams. PhD, and
Edgar R. Monterroso, MD
Objectives: This study examined
correlates of prevalent hepatitis C virus (Hepatitis C Virus) infection
among young adult injection drug users in 2 neighborhoods in
New York City.
Methods: Infection drug users aged
18 to 29 years were street recruited from the Lower East Side
and Harlem. Participants
were interviewed about drug use and sex practices;
venipuncture was performed for hepatitis B virus (HBV), Hepatitis C Virus,
and HIV serologies.
Results: In both sites, testing
positive for Hepatitis C Virus antibody (anti-Hepatitis C Virus) was associated with
having injected for more than 3 years.
Additionally, Hepatitis C Virus infection was positively associated
with injecting with someone known to have had hepatitis (but
the association was significant only in the Lower east Side)
and with sharing cotton (but the association was statistically
significant only in Harlem).
Being in drug treatment and older than 24 years were
associated with Hepatitis C Virus in the Lower East Side but not in Harlem.
Receiving money for sex was associated with anti-Hepatitis C Virus
positively in Harlem but not in the Lower East Side.
Conclusion: Several differences in
factors associated with prevalent Hepatitis C Virus infection existed among
2 populations of young injection drug users from the same
transmission of Hepatitis C Virus may occur.
(Am J Public Health 2001; 91: 23-30)
drug users are at high risk for hepatitis C virus (Hepatitis C Virus)
infection.1-3 Although geographic variation exists,
Hepatitis C Virus rates among injection drug users are often higher than 60%
and in many cities approach 90%.4-7 A recent study
in Baltimore, Md, showed that Hepatitis C Virus infection rates were 60%
among injection drug users with less than 2 years ' experience
with injection.8 If transmission is indeed this
rapid (and efficient), then more aggressive public health
measures are needed to reduce trans- mission in this
vulnerable population. Aggressive prevention of Hepatitis C Virus also is
important be- cause therapy for Hepatitis C Virus is costly and, so far in
the United States, usually not offered to active injection
drug users!'3 Unfortunately, some studies suggest that high
Hepatitis C Virus infection incidence among injection drug users is the
result of the already high proportion with chronic infection
(approaching 85% of those infected), providing a huge
reservoir from which trans- mission can occur.2
High Hepatitis C Virus prevalence among young injectors from different
locations adds additional urgency to the call for more in-
tense and sustained preventive measures.
The purpose of this study was to examine rates
and correlates of Hepatitis C Virus infection among young adult (mostly
recent onset) injection drug users in 2 very different
neighborhoods in New York City: the Lower East Side and
Harlem. We examined factors associated with prevalent Hepatitis C Virus
infection from baseline inter- views conducted from 1997
through 1998 among injection drug users aged 18 to 29 years in
these 2 neighborhoods.
The study population was recruited
(during 1997-1998) as part of a cohort study from 2 of 6
Centers for Disease Control and Prevention
sites for the Collaborative Injection Drug User Study II. The
2 New York City sites were located in the Lower East
Side (conducted by Beth Israel Medical Center and National
Development and Research Institutes) and in Central and East
Harlem (conducted by Center for Urban Epidemiologic Studies,
New York Academy of Medicine ). Eligibility criteria and the
core questionnaire were the same for all sites; recruitment
methods may have varied slightly by sites, but for all sites,
street recruitment (not recruitment from drug treatment
programs) was the focus.
To be eligible for the study,
participants needed for more of the following criteria: to
report injection drug use during the previous 6 months, to
have injected for less than 3 years, or to be between 18 and
29 years of age. Potential participants were asked a series of
questions unrelated to the eligibility criteria (e.g.,
"Do you have siblings?"). The eligibility criteria
were not advertised because we thought that knowledge of these
criteria might lead persons to falsely represent their
injection practices and age in order to enter the study.
Because few injection drug users older than 29 had injected
for less than 3 years, for this analysis we included only
persons between 18 and 29 years of age.
The Harlem study, known as Harlem
Out-reach Prevention and Education, was conducted from a
building in Central Harlem, New York City. Recruitment took
place in both Central Harlem (predominantly African American)
and East Harlem (predominantly Latino).
For the Lower East Side, the study
was conducted in a research storefront office located in that
neighborhood. The research store- front has been in continuous
operation since 1989 and is well known among drug users in the
community. The Lower East Side is an ethnically diverse
neighborhood with a large transient population of young White
persons from nearby suburbs and the rest of the United States.
outreach techniques were used to recruit young adult injection
drug users. First, ethnographic techniques were used to map
Central and East Harlem and the Lower East Side to determine
specific areas where young injection drug users congregated.
Recruiters were then sent to these areas, where they
approached young persons, engaged them in conversation,
formally assessed eligibility by asking structured questions,
and asked persons who were eligible to participate in the
study. Those who agreed to participate in the study were
escorted to the study office to receive information about the
study and provide informed consent. They also were given a
small monetary incentive ($25) after completion of an
At baseline, eligible and
consenting participants unde1Went standardized face-to-face
interviews conducted by trained interviewers in private rooms
as well as venipuncture. Participants received pretest
counseling about the serologic tests (Hrv; hepatitis E virus
(HEY], and Hepatitis C Virus). Participants were given risk reduction
counseling and referral information for services such as drug
treatment and social services. To minimize bias, however, this
was not done until after the interview was completed.
All participants were offered test
results and posttest counseling. Participants with any
positive test results were offered referrals for follow-up
medical evaluation. Those with negative HBV test results were
offered referral for hepatitis B vaccination. The study
received institutional review board approval from Beth Israel
Medical Center, the National Development and Research
Institutes, the New York City Department of Health, and the
Centers for Disease Control and Prevention.
The interview included questions on sociodemographics, injecting
behaviors, sexual behaviors, and quasi networks. Drug use
questions included age at which the participant first injected
drugs and the age of the person(s) who initiated the
participant into injection drug use. Other drug use questions
focused on the 6 months prior to the interview and included
frequency of injecting, type(s) of drug injected, use of
direct sharing (using a syringe after someone else) and
indirect sharing (using cot- ton, rinse water, or a cooker
after someone else), and use of syringe exchange or drug
treatment. Sex practice variables, including number of sex
partners, sexual preference, exchange of sex for money or
drugs, and use of condoms (separately for steady and
non-steady partners), were ascertained for 6 months preceding
the interview. Finally, persons were asked whether they had
ever been raped, been in prison, or injected with someone
known to have had hepatitis (quasi network).
Serum from blood specimens was
analyzed for HIV-I antibodies by standard techniques at local
laboratories. Specimens repeatedly reactive on enzyme-linked
immunosorbent assay were confirmed with Western blot.
specimens were sent to the Centers for Disease Control and
Prevention to test serologic markers for HBV arid Hepatitis C Virus
infection. Samples were tested for antibody to Hepatitis C Virus (Abbott Hepatitis C Virus
EIA 2.0, Abbott Laboratories, Chicago, Ill). A sample of 100
specimens repeatedly reactive for Hepatitis C Virus based on enzyme
immunoassay received supplemental testing, and results for all
were found to be positive. Because of the high positive
predictive value of repeat reactive enzyme immunoassay testing
in this population, no further supplemental Hepatitis C Virus testing was
performed. Therefore, persons with positive repeat reactive
enzyme immunoassay test results were considered to have
evidence of past Hepatitis C Virus infection.
Samples were tested for antibody to
HBV core antigen (anti-HBc) (CORAB, Abbon Laboratories,
Chicago, III). Samples testing positive for anti-HBc were then
tested for hepatitis B surface antigen (HBsAg) (AUSAB EIA,
Abbon Laboratories), and if the results were negative, the
samples were tested for antibody to HBsAg (anti-HBs) (AUSTRIA
II-125,Ab- bon Laboratories). Because of this sequence of
testing, many serum samples of blood did not contain
sufficient amounts for the anti-HBs testing. Therefore, in the
analysis, only data on anti-HBc and HBsAg are presented.
Persons with positive test results for either anti-HBC alone
or for anti-HBc in combination with HBsAg were considered to
have evidence of HBV infection.
Initial frequency comparisons were
made between the 2 sites to examine the proportion of subjects
by sociodemographic characteristics; initiation of injection
drug use; gender; whether participants had ever been raped or
been in prison; quasi network; HC~ HB~ and HN status; and drug
use behaviors and sexual behaviors in the past 6 months.
The prevalence of Hepatitis C Virus infection by
num- her of years of injection drug use was calculated
separately for each site, and Mantel-Haenszel X2 tests for
linear trend were used to determine whether Hepatitis C Virus infection was
associated with the number of years of injection drug use.
Within each site, contingency
tables with prevalence odds ratios (ORs) and 95% confidence
intervals (CIs) were used to study un- adjusted associations
between different risk factors and Hepatitis C Virus infection. Because of
the great differences between Harlem and the Lower East Side,
these associations were examined separately for each site.
study adjusted associations between risk factors and Hepatitis C Virus
infection, we developed multivariate logistic regression
models separately for each site in the following manner. All
factors found in the univariate analysis for the given site to
have prevalence odds ratios that (with 95% confidence
intervals) excluded unity were entered into each model. HBV
infection was not considered because it is an out- come of the
same risky behavior that leads to Hepatitis C Virus infection.
Backward stepwise elimination was
done with SAS (SAS Institute Inc, Cary, NC) de- fault criteria
for removal from the model. For each site-specific analysis,
the remaining variables were examined for collinearity (i.e.,
Pearson correlation coefficient>O.5) within each site. The
following pairs of variables were found to be collinear within
both sites: (1) use
1-Baseline Sociodemographics, Lifetime Events, Network,
Behaviors, and Serologic Test Results of Young Injection Drug
Users in New York City, by Site of Recruitment