Tuesday, April 5, 2011

The problems with Circumcision & HIV

I'm very worried about a potential public health disaster because In recent years there has been much media publicity that circumcision reduces the risk of HIV infections, however, what has lacked in this media coverage is an in-depth critical analysis of the research and a wider look at other data that exists that refutes this proposition.

Firstly, if we look at the much vaunted African Clinical trials we can find many faults as follows:

The research did not prove life-long protection only partial episodic protection, which is not absolute risk reduction & only relative risk reduction (relative to the trial conditions for only 18months).  The trials were conducted over an 18month period, and in some areas they were highly controlled clinical trials, and in other areas they were poorly controlled clinical trials.  The trials also did not reflect not real world settings, and therefore how can they be applicable to real world settings.

Rarely reported or emphasised, A significant number of circumcised men in the study became infected with HIV.  This fact often gets over-looked in the pro-circ spin.

The participants were not randomly selected, but selected themselves, creating a potential bias or distortion in the generalisability of the results to any general population.  The participants were paid adult male volunteers who wanted to be circumcised and therefore had a bias in favor of it, and could possibly have been in favour of circumcision because they were high risk candidates who had unprotected sex (no condoms) with multiple sex partners. Therefore as the particpants were not randomly selected, and a potentially biased self-selected sample of the population, the results cannot be extrapolated to general populations outside of this population sub-group.  (Van Howe & Storms, 2011)

Inadequate Controls: Participants in the trials were not treated equally with the circumcised group given more education about healing from surgery, advised to not resume sex for 6 to 8 weeks and therefore, abstained from sex longer, and participants were given greater time and emphasis about wearing condoms during the period of healing from surgery. No control was undertaken to examine possible non-sexual blood exposures by participants.  No control was undertaken for dry sex as practised by some african cultures. No control for the sex (gender) of partners, and no control for anal intercourse. (Van Howe & Storms, 2011)

Unexplained and disrtorting the statistics was the finding that in the first three months of the Kenyan trial, five men became HIV-positive who reported no sexual activity in the period before the seroconversion (0.73/100 person-years, 95%CI=0.30-1.76). (Van Howe & Storms, 2011)

Data suggests a percentage of infections were from non-sexual exposures, with 23 infected men reporting no sexual contact without a condom.  No explanations or investigations undertaken for non-sexual exposures to HIV infections. (Van Howe & Storms, 2011)

The African HIV Trial researchers were all pro-circumcision and with a history of activism in the area.

Nearly 10 times as many participants dropped out of the clinical studies as were infected, with HIV status unknown.

The studies were ended early exagerrating effects.

The vast majority of participants in the study were HIV free, therefore, why was no attempt made by researchers to identify the 100% condom users and compare these to the circumcised group, Was 100% condom use more effective than circumcision = Most probably yes!! but researchers did not want to find this and report it. 

No long term follow-up possible with all subjects circumcised at end of trial.

Researchers used speculative hypotheses to explain trial findings, such as Langeran present in the foreskin cells are targeted by HIV, whereas later research found Langeran cells actually kill HIV. (Van Howe & Storms, 2011)

The studies had such high numbers of participants leading to an overpowering of the statistical analysis, inflating the results. (Van Howe & Storms, 2011)

At best the reseach findings are only valid for adult circumcision volunteers, and populations with high prevalence of HIV, not babies or low prevalence nations, at worst the research is so floored the findings only have validity within similar research conditions and virtually zero validity for real world situations.

In another study, Women who had sex with circumcised men were 50% more likely to become infected with HIV. 

Demographic studies in Africa have found many circumcised populations have higher HIV infection rates than non-cirumcised populations. 

Chao et al found Rwandan women who's partners were circumcised at higher risk of HIV.

The USA which circumcises has much higher HIV than western Europe which doesnt circumcise, showing that clinical trials and real world have little in common with each other.

French demographer Garenne demonstrated that interventions with a near 50% clinical trial efficacy had very little population effect.

Anti-viral drugs have shown a 90 to 95% reduction in HIV infections.

HIV infections are caused by behaviours (Unprotected/Unsafe sex with Multiple sex partners) and therefore behavioural interventions are more important than surgical interventions, which may lead to a false sense of security and increase unsafe sex behaviours with multiple sex partners.

The strong message here needs to be safe sex and condoms can only prevent HIV, and a false belief in the protection of circumcision places men and women at greater risk of infection.

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