Heroin users who think
they can avoid the harmful consequences of drug injection by snorting or
smoking the drug may be dangerously mistaken. A NIDA-funded study
indicates that noninjecting heroin users (NIUs) are at considerable risk
of becoming drug injectors, thereby incurring risks for HIV, hepatitis,
and other serious diseases. Moreover, regardless of whether they go on to
inject drugs, a significant number contract hepatitis, the study shows.
|"This is the era of
AIDS, and everyone knows about the risks from needles. When you
sniff, you don't have to worry about AIDS."
- Noninjecting heroin user
interviewed in New York
"Becoming a drug injector is not inevitable for heroin snorters who
have never injected drugs, but the risk of making the transition to
injection drug use is fairly substantial," says Dr. Alan Neaigus of
National Development and Research Institutes (NDRI), Inc., in New York
City. Dr. Neaigus and his colleagues at NDRI have been examining rates of
transition to injection drug use and disease incidence among 560 NIUs
recruited from March 1996 through April 1998. The study group consists of
heroin users who have never injected drugs and former heroin injectors who
had not injected drugs for at least 6 months prior to the study. Data from
followup interviews conducted with 331 study participants show that more
than 15 percent transitioned to drug injection during an average period of
a little more than a year. The researchers found no significant difference
in the transition rate between NIUs who had never injected heroin and the
31 percent of the study group who were former injectors.
Previous studies have found higher rates of transition from
noninjection to injection drug use, particularly among former injectors.
However, Dr. Neagius says a number of factors may now be slowing the rate
at which heroin snorters are initiating or resuming injection of the drug.
First, a dramatic increase in the purity of heroin during the 1990s has
made it possible for snorters to achieve a high that is similar to what
they can obtain from injection. Second, greater awareness of the risk of
contracting AIDS from injecting drugs may be dissuading more users from
The NIU study supported earlier research findings that NIUs who
socialize, use drugs, or have sex with IDUs significantly increase their
risk of crossing the line from snorting to injecting drugs. Preliminary
analysis further suggests that being in the presence of an IDU who is
injecting drugs may play an important role both in the initiation and
resumption of injection drug use, Dr. Neaigus says. This finding suggests
that the direct transfer of information and techniques used to inject
drugs may be an important factor in the transition to injection drug use.
The level of heroin addiction is another major factor in the transition
to injection. The NIU study participants' levels of addiction ranged from
snorting heroin occasionally on weekends through using several bags a day,
Dr. Neaigus says. Previous research has suggested that even with the
availability of high-purity heroin, more heavily addicted heroin snorters
may turn to drug injection because it remains a more effective way to take
the drug. For example, in a study conducted between 1991 and 1993 by Dr.
Samuel R. Friedman, also of NDRI, 30 percent of 755 IDUs in Brooklyn, New
York, reported they started to inject to get a better high.
NIUs and Infectious Disease
The health risks associated with noninjecting heroin use are
substantial, both for NIUs who become IDUs and for those who don't, the
study found. All study participants received counseling about the risks of
drug injection, hepatitis, and HIV. Nevertheless, almost 23 percent of the
NIUs who began to inject drugs contracted hepatitis C (HCV) over the
average followup period of a little over a year. HCV leads to chronic
liver infection in about 80 percent of patients, most of whom eventually
develop fatal liver diseases such as cirrhosis and liver cancer, says Dr.
Henry Francis, who directs NIDA's Center on AIDS and Other Medical
Consequences of Drug Abuse.
Because injection drug use is
the primary mode of HCV transmission, "the rapid rate of transmission of
hepatitis C among NIUs who initiate or resume injecting was expected," Dr.
Neaigus says. "However, it is still alarming," he adds. What was
unexpected was that some NIUs who did not begin to inject drugsÑabout 4
percentÑalso contracted HCV during the followup period. NDRI researchers
now are attempting to determine how these NIUs contracted the infection,
Dr. Neaigus says.
|NIUs who socialize,
use drugs, or have sex with IDUs significantly increase their risk
of crossing the line from snorting to injecting
NIUs who did not transition to injection drug use were also at
substantial risk of becoming infected with hepatitis B (HBV), the study
shows. About 9.5 percent contracted HBV during the followup period. Though
it receives less attention than HCV, HBV can develop into chronic
infection and serious liver disease in up to 20 percent of cases, says
NIDA's Dr. Francis.
The considerable amount of HBV found among NIUs, particularly among
those who have never injected, reflects substantial sexual transmission of
this disease, Dr. Neaigus says. Though the study only measured sexual
activity over a 30-day period, "we found a lot of sexual risk in this
group," he says. For example, about 70 percent of NIUs were sexually
active during this period with two-thirds of them engaging in unprotected
sex, many with partners who had HIV or were IDUs, says Dr. Neaigus.
|Hepatitis C Among Noninjecting Heroin Users|
|Drug injection is the primary mode of hepatitis C
transmission. In a New York City study, a large percentage of
noninjecting heroin users who transitioned to injection drug use
contracted the disease.|
To date, the study has not found any new cases of HIV either among NIUs
who began injecting drugs or among those who did not. However, Dr. Neaigus
says that the high rates of new HBV and HCV infections found among NIUs
may serve as markers for sexual behaviors and drug injection practices
that continue to put NIUs at risk for infection with HIV. In addition to
finding extensive high-risk sexual activity among NIUs, the study found
NIUs who had recently transitioned to injection drug use commonly shared
injection equipment, such as cookers, cotton, and rinse water. However,
they infrequently shared syringes and over half obtained all their
syringes from syringe exchange programs.
Noninjection drug use is two-edged in its effect on heroin users' risk
of contracting infectious diseases, Dr. Neaigus concludes. On the one
hand, the considerable numbers of former IDUs who are now snorting heroin
instead of injecting it have reduced their risk of AIDS and HCV
considerably. On the other hand, NIUs who have never used heroin before
have increased their risk of heroin addiction, transition to injection
drug use, and contracting HIV, HCV, and HBV.
Neaigus, A., et al. Trends in the noninjected use of heroin and factors
associated with the transition to injecting. In J.A. Inciardi and L.D.
Harrison (eds.), Heroin in the Age of Crack Cocaine, Thousand Oaks,
CA: Sage Publications, Inc., pp. 131-159, 1998.
Neaigus, A.; Friedman, S.R.; Hagen, D.L.; Miller, M.; and Des Jarlais,
D.C. Transitions to injecting and seroconversions for HIV, hepatitis B,
and hepatitis C among non-injecting heroin users. Paper presented at the
12th World AIDS Conference, Geneva, 1998.
Neaigus, A.; Hagen, D.L.; Friedman, S.R.; Miller, M.; and Des Jarlais,
D.C. Transitions to injecting drug use among non-injecting heroin users.
Paper presented at the American Public Health Association annual meeting,
Washington, DC, 1998.