Is the recent emergence of mephedrone injecting in the United Kingdom associated with elevated risk behaviours and blood borne virus infection?

Abstract

The recent, and rapid, emergence of injection of the short-acting stimulant mephedrone (4-methylmethcathione) has resulted in concerns about increased infection risks among people who inject drugs (PWID). Data from the bio-behavioural surveillance of PWID in the United Kingdom were analysed to examine the impact of mephedrone injection on infections among PWID. During the year preceding the survey, 8.0% of PWID (163/2,047) had injected mephedrone. In multivariable analyses, those injecting mephedrone were younger, less likely to have injected opiates, and more likely to have injected cocaine or amphetamines, used needle/syringe programmes or sexual health clinics, been recruited in Wales and Northern Ireland or shared needles/syringes. There were no differences in sexual risks. Those injecting mephedrone more often had hepatitis C antibodies (adjusted odds ratio (AOR) = 1.51; 95% confidence interval (CI): 1.08–2.12), human immunodeficiency virus (AOR = 5.43; 95% CI: 1.90–15.5) and overdosed (AOR = 1.70; 95% CI: 1.12– 2.57). There were no differences in the frequency of injecting site infections or prevalence of hepatitis B. The elevated levels of risk and infections are a concern considering its recent emergence. Mephedrone injection may currently be focused among higher-risk or more vulnerable groups. Targeted responses are needed to prevent an increase in harm.