Passing the test: allocating antiretroviral therapy in Malawi

How can expensive antiretroviral therapy be best prioritised in under-resourced health systems? In Malawi, targeting laboratory-based tests that measure the progress of the disease may offer one solution to help target those most in need.

Almostone million people suffer from HIV or AIDS in Malawi. By March 2004, only threepercent of Malawians who needed antiretroviral therapy (ART) were receiving it.Plans to increase the number to 80,000 (50 percent of those needing treatment),will need to ensure that the most urgent cases are effectively targeted.

Alaboratory test, known as the CD4 test, is often used to decide when someoneneeds ART treatment. The test is a "proxy" for the state of thebody's capacity to defend itself against infections. A CD4 count under athreshold level of 350 cells per unit of measurement (microliter, ul) is considered a low level and the body is less able todefend itself against infections. ART treatment is then considered necessary.However, the CD4 test is expensive and high-tech.

TheWorld Health Organisation recommends that in poor countries ART should be givento everyone who has reached stage III and IV of the disease. Médecins sans Frontières and theMinistry of Health of Malawi carried out a study to find out whether all peoplein stage III and IV did in fact need ART.

ReceivingART too soon could mean that the body becomes resistant to the drugs and thetreatment is no longer effective when the patient most needs it. In additionthere is the inconvenience of taking the tablets, of possible side effects, andthe need for follow-up visits to the hospital. The study was carried out inThyolo district, a rural part of southern Malawi, between April 2003 andJanuary 2004. Everyone over the age of 13, who attended the district hospitalwith AIDS stage III or stage IV, was included in the study.

Thestudy found that out of the 401 people studied:

• Seventy-four percent currently had an active disease associated withHIV/AIDS, whilst the other 26 percent came to the hospital for a routinefollow-up visit or with other health problems.
• Thirty-two percent were malnourished, 46 percent were below what isexpected to be a normal, while 22 percent were rather plump or obese (a highBody Mass Index (BMI).
• Nine percent had a CD4 count of more than 350 cells per microliter andtherefore did not require ART at that time.
• The patients with a high CD4 count were more likely to be plump oroverweight and did not have an active disease associated with HIV/AIDS.

Thestudy recommends that, while it is not possible to offer everybody CD4 testing:

• patients with a high BMI and those with no apparent activedisease associated with HIV/AIDS should have the CD4 test, as a considerableproportion of these subgroups may not yet require ART.
• Routinely screening for such patients in clinics would help target theCD4 test and save resources both in terms of CD4 tests and ART.
• Targeting CD4 testing would also mean smallernumbers of people would be required to undergo CD4 testing and this opens thepossibility of using less costly, and less sophisticated instruments for CD4testing in resource-limited settings.

While targeted CD4 testing may notidentify all those with high CD4 counts, it does prevent a considerable numberof people from receiving early ART treatment thus saving unnecessary costsassociated with ART. In Malawi, the saving could be as much as two million USdollars per year.