Crystal Methamphetamine Injection Predicts Slower HIV RNA

Suppression among Injection Drug Users

Nadia Fairbairn1

Thomas Kerr1, 2

M-J Milloy1

Ruth Zhang1

Julio Montaner1, 2

Evan Wood1, 2

1 Urban Health Research Initiative of the British Columbia Centre for Excellence in HIV/AIDS

2 Division of AIDS, Department of Medicine, University of British Columbia

• Crystal methamphetamine is a stimulant drug with higher purity than powdered methamphetamine

• Reports of increasing crystal methamphetamine production and consumption globally

• Major implications for HIV prevention and treatment strategies

Background

Amphetamine-type stimulant seizures in 2008

UNODC World Drug Report 2010

• 66% Bangkok injection drug users (IDUs) reported injecting methamphetamine (Werb et al., 2009)

• Methamphetamine injection associated with HIV risk behavior syringe sharing in Bangkok (Hayashi et al., IAC 2010 WEPE0269)

• Australia and the U.S. have documented increases in crystal methamphetamine injection among drug users

Background

• Injection and non-injection crystal methamphetamine use increasing in Vancouver, Canada

Background

Fairbairn et al., 2007

• Crystal methamphetamine use linked to: • Sexual risk behaviors• Increased likelihood of HIV seroconversion• Poor adherence to antiretroviral therapy

• Injection of crystal methamphetamine associated with syringe sharing

• Not much known about the impact of crystal methamphetamine use on the outcomes of HIV treatment

Background

Objective

• To examine the association between crystal methamphetamine injection and plasma HIV RNA suppression among a cohort of HIV-positive injection drug users initiating ART

Methods

• The ACCESS cohort is an ongoing prospective cohort of HIV-positive individuals who inject drugs

• Participants recruited through self-referral and street outreach from Vancouver’s Downtown Eastside since 1996

• At baseline and semi-annually participants provide blood sample and complete questionnaire

Methods• Primary endpoint of analysis: time to plasma viral

load suppression <500 copies/mL from start of ART

• Primary independent variable of interest: use of injection crystal methamphetamine

• Variables: Daily heroin and cocaine injection, crack smoking Gender, age, ethnicity Baseline viral load (per log10) Baseline CD4 cell count (per 100 cells/mm3)

• Multivariate model fit using an a priori defined model-building approach

Have you injected crystal methamphetamine in the last 6 months?

Yes No Yes

No90.6%

Results• Sample characteristics (n=708):

384 (54.2%) ART-naïve participants initiated HAART 163 (42.5%) female respondents Median follow-up 18 months (inter-quartile range 6 - 49)

36 (9.4%)reported crystal meth injection at any time during follow-up.

ACCESS Cohort (n=708)

• Primary outcome of interest:

HIV RNA Suppression Baseline Viral

Load0.86(0.73 – 1.00)

p = 0.064

Adjusted** Relative Hazard(95% CIs)

Baseline CD4 Count 0.90(0.84 – 0.96)

p < 0.001

Crystal methamphetamine injection*

* Behaviors refer to activities in the last 6 months.

** Model was also adjusted for age, heroin injection and cocaine injection.

• Multivariate Cox Regression analyses

0.63(0.40 – 0.98)

p = 0.039

Multivariate Cox Regression analysis of factors independently associated with time to HIV RNA suppression <500 copies/mL.

Interpretations

• Crystal methamphetamine injection independently and negatively associated with plasma HIV RNA suppression

• Psychopharmacological effects of crystal methamphetamine may undermine antiretroviral treatment adherence

• Some evidence for direct effects on HIV disease progression

Interpretations

• Crystal methamphetamine production is a highly profitable and easily concealable endeavor

• Demand for the drug is increasing

• Legal remedies and law enforcement may have negligible impact on use

• Urgent need for evidence-based HIV prevention and treatment programs for crystal methamphetamine injectors

Limitations

• Findings possibly conservative due to socially desirable reporting

• Sample not randomly selected, findings may not generalize to other IDU

• Further research needed to examine impact of methamphetamine use on HIV pathogenesis

Conclusion

• These findings contribute further evidence to the negative health outcomes associated with crystal methamphetamine use

• Expansion of treatment programs and implementation of novel interventions for crystal methamphetamine injectors urgently needed

Acknowledgements

• ACCESS participants• ACCESS investigators and staff: Deborah

Graham, Tricia Collingham, Caitlin Johnston, Steve Kain, and Calvin Lai

• US National Institutes of Health • Canadian Institutes of Health Research