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Health Psychology Lecture 8 Chronic Illness and AIDS.

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1 Health Psychology Lecture 8 Chronic Illness and AIDS

2 Press Release In a paper to be published soon, an Australian obstetrician has suggested that the foreskin accounts for 80 per cent of infections from males. The evidence? Comparisons of infection rates between those countries that practice circumcision - Thailand, India and Cambodia - and those that don’t - The Phillipines, Bangladesh and Indonesia. The rates are 10 to 50 times higher in the latter than the former! Too simple to be true? And the answer: a worldwide circumcision drive? Too painful to contemplate?

3 Press Release Why do you think it is that people don't want to hear about it? “Well, I mean it's so laughably simple, I think. That's probably one of the things against it. One would have thought that, you know, years ago people ought to be asking, if I can use the pun, the seminal question of how is it that HIV virus actually gets into the male reproductive tract? How does it get into the female reproductive tract? And we've been so obsessed with developing vaccines and developing drugs that might combat the infection that we've forgotten the simple first principle of how does the virus enter the body?” ABC radio, March 2000

4 Evidence? H 1 : Male circumcision lowers HIV risk How could you test this hypothesis? Design at least 2 studies to test this hypothesis.

5 Evidence? Epidemiological Survey Controlled Randomized Trials (CRTs)

6 Epidemiology - HIV and Circumcision HIVUncircumcised

7 Epidemiological Data Meta-analysis (Weiss, 2002) –Method: 38 epidemiological studies –Results: risk ratio =.52 –Conclusion: “Observational evidence for a protective effect of MC on risk of HIV infection is strong and consistent” –Caveats: Related to risk of infection (hard to assess transmission) –Implications:

8 Need for Clinical Trials (Bailey et al.) “Randomized clinical trials are needed to determine the utility of circumcision as an HIV preventive measure.” Reasons: –All epidemiological studies to date have been observational (cannot exclude residual confounding) and not all results are consistent. –Risk of too early resumption of sexual activity after circumcision or subsequent behavioural disinhibition could counteract any protective effect. –Risk of post-surgical complications must be balanced against any protective effect.

9 Acceptability of adult MC in Zimbabwe Daniel Halperin, Katherine Fritz, Willi McFarland, Godfrey Woelk Univ. of Calif, San Francisco; Univ. of Zimbabwe Medical College –200 men interviewed: randomly sampled at beer hall settings in Harare, 2000. –14% circumcised (self-report). –Of the uncircumcised men, 45% said they would like to be circumcised if it were performed safely and were affordable.

10 Acceptability Studies Interviews with 1178 uncircumcised men –60% said they would accept circumcision and be willing to enroll in a RCT, even with delayed circumcision –Acceptance highest in 20-29 age group (65%) Focus groups –Circumcision acceptable for health/hygiene –No concerns about religious connotations “Jesus was circumcised” –Women prefer men to be circumcised

11 Willingness to Participate (Bailey et al.) 86% of 18-25 year-olds said they would prefer to be circumcised. 97/103 (94%) said they want to participate in the trial. Reasons given –Free circumcision –Free medical treatment for two years –Compensation for time and transport –Getting free counselling about safe behaviours

12 Randomized Clinical Trials At least 3 trials (Zimbabwe, Cameroon, South Africa) Randomized, unblinded: circumcision/no circumcision Both arms: HIV testing, behavioral questionnaire, medical examination, STD testing and HIV prevention counselling at baseline, and at 6, 12, 18 and 24 months post-enrolment. Additional HIV testing at 1 and 3 months. Circumcision arm: Post-operative check-ups at 3 days, 8 days and 30 days after the procedure.

13 Hypotheses Circumcision will reduce HIV incidence among men aged 18-24 years by 50%. Circumcision will result in less than a 2% rate of significant post-surgical complications requiring follow-up care. There will be no difference between circumcised men and controls in reported sexual behaviour following the circumcision procedure.

14 The “Disinhibition Effect” An increase in unsafe behaviors in response to the introduction of a preventive or therapeutic intervention Applies to any field of public health, not just HIV - seat belts/reckless driving - chest x-ray/tobacco use - anesthesia for childbirth/sexual activity

15 What should we do now? (Weiss, 2002) Disseminate current evidence Continue studies of acceptability & feasibility of MC in non-circumcising populations with high incidence of HIV Assess safety of current circumcising procedures Develop affordable services for safe voluntary MC Develop psychoeducational materials that: –emphasise that MC may reduce but not eliminate risk of HIV infection –Separate out issues of male and female circumcision

16 … so it all sounds pretty persuasive? Another explanation???


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