Sniffing or snorting heroin in combination with cocaine appear to significantly increase the risk of becoming infected with hepatitis C even for drug users who do not use needles, according to New York City researchers.
The high rate of hepatitis C among injecting drug users -- who frequently share syringes, a common method of transmission of the virus -- is easy to understand.
But researchers have long been puzzled as to why the prevalence of hepatitis C infection among noninjecting drug users is higher than for the general population. This new study involving 276 noninjecting drug users, reported in the Journal of Medical Virology, may provide one answer.
When the researchers interviewed study participants about risk behaviors, they found that those who "ever sniffed or snorted heroin in combination with cocaine were significantly more likely to be infected with hepatitis C compared with those who never sniffed or snorted heroin with cocaine."
Researchers theorized that sniffing or snorting more drugs increases the likelihood of irritating the nasal vascular wall, resulting in bleeding in the nose. And that, in turn, might increase the likelihood of transmission of the hepatitis C virus when straws or rolled up dollar bills used to sniff or snort drugs are shared.
"These findings suggest that sniffing or snorting heroin with cocaine may explain the increase frequently found in hepatitis C infection among noninjectors, but further studies are necessary," the researchers concluded..
Other sources: Journal of Medical Virology