Implications of CT on disinhibition among HIV negatives

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Implications of CT on disinhibition among HIV
negatives

• Dr Liz Corbett
• Wellcome Trust Senior Research Fellow
• Reader, London Sch Hyg Trop Med

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Contents

• Background
• Evidence for disinhibition following CT
• Limitations of what we know
• Implications and conclusions

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Background

• CT and HIV prevention
• Significant beneficial impact on behaviour /-
  STIs
• Following presentation with STI (RESPECT USA)
• For discordant couples
• If HIVves
• Only RESPECT has shown an impact in HIV-ves
• Subsequent suggestions of increased risk
  behaviour or disinhibition

Weinhardt et al Am.J.Pub Hlth 1999891397
Denison et al AIDS Behav 2007 epub
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Why might disinhibition occur?

• Risk compensation
• Concern to biomedical HIV prevention
  interventions
• Microbicides / circumcision / vaccines
• Familiar to all car drivers
• Perceived safety tends to increase speed
• Could this apply to CT?
• Got away with own risky behaviour before
• Feel immune
• More willing to repeat those risks
• Less worried about partners status/behaviour
• Farquhar et al

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Evidence for disinhibition after CT

• Workplace CT intervention
• Harare, Zimbabwe
• Biological endpoint HIV incidence at 24mos
• Manicaland Project
• Eastern Zimbabwe
• Behavioural endpoint 24 mos after last
  assessment
• RESPECT-2 trial
• USA
• Behavioural biological outcome STI incidence
  at 12 mos

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Workplace VCT trial, Harare
Corbett et al PLoS Med 2006 3 e238
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Corbett EL et al. AIDS 200721483-9
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HIV incidence in 2,996 participants 1.37 per 100
PY on-site VCT sites 0.95 per 100 PY off-site VCT
sites Relative risk 1.49 (0.79 to 2.80) 49
increased risk of becoming HIV infected under
high uptake VCT strategy, but not significant
Corbett EL et al. AIDS 200721483-9
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Reported change in risk behaviourHIV-ve
individuals beforeafter VCT compared to HIV-ve
individuals who did not have VCT5,775
individuals interviewed in both 1998 and 2000
Increased risk
Decreased risk
Sherr L et al AIDS 2007 21 851
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RESPECT-2 USA STI clinics

• Randomised trial comparing
• Rapid HIV tests with same day results
• versus lab ELISA with HIV results in 1 wk
• Both arms same counselling
• 3,298 HIV-ve participants 73 follow-up to 12
  mos
• Results
• Significantly higher receipt of results with
  rapids
• But higher incidence of repeat STIs with rapids
• Significantly so in men
• 47 and 34 increase over lab ELISA at 6 12 mos
• Rapid receipt of results less effective at
  changing behaviour?

Metcalf et al Sex.Transm.Dis 200532130-8
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Meta-analysis of 7 VCT studies in developing
countries

• VCT recipients (before after or compared to
  non-recipients)
• Less unprotected sex reported OR 1.69 95CI
  1.252.31
• Number of sex partners similar OR 1.22 95CI
  0.891.67
• Biggest effects in studies including discordant
  couples or HIVve participants

Denison et al AIDS Behav 2007 epub ahead of print
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Summary and limitations

• 3 studies showing hints of behavioural
  disinhibition
• Rapid testing
• None conclusive
• Only significant results from subgroup analysis
• None the less
• Very worrying
• Effects not small!

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Summary and limitations

• 3 studies showing hints of behavioural
  disinhibition
• Rapid testing
• None conclusive
• Only significant results from subgroup analysis
• None the less
• Very worrying
• Effects not small!

• Implications?
• Formal studies needed
• Long term outcomes of different CT strategies
• In HIV-positives
• In HIV-negatives
• Is this something about same day results?
• If confirmed major public health significance

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Conclusions

• Worrying, but inconclusive trail of evidence for
  disinhibition following CT with same day results
  in HIV-ves
• All current studies point in the same direction
• Could be a major effect
• To maximise HIV prevention we need to know
• If disinhibition does occur then
• Who is most at risk?
• What CT factors contribute?
• What client beliefs contribute?
• How to pre-empt it with more effective
  counselling
• Meantime
• Be aware of potential risk of disinhibition
• Communicate this to clients
• Report outcomes post-VCT stratified by clients
  HIV status

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