Writing in the journal Neurology, the researchers said their study also pointed to a way to measure this progressive brain damage when it does occur.
The AIDS drugs combinations, known as highly active antiretroviral therapy or HAART, suppress the virus but do not remove it completely from the body. Patients are not cured, but their immune systems are not as badly damaged as untreated patients.
HIV can also attack the brain and nerves. Before HAART was available, about 20 percent of people with AIDS developed dementia. But not all of the drugs used in these mixtures get into the brain, so it was not clear how much they helped.
Effects after three months
Dr Asa Mellgren of Goteborg University in Sweden and colleagues studied 53 men and women infected with HIV. They tested their cerebrospinal fluid, then gave them HAART for one year.
Before treatment, 21 of the patients had high levels of a protein called neurofilament light protein, which was believed to be a biological marker for brain damage.
After three months of taking HAART, the high levels of the protein fell to normal levels in nearly half of the patients. After one year of treatment, only four people still had high levels of the protein, they reported.
All but one of the patients with normal levels remained normal for the year.
"This type of treatment appears to halt the neurodegenerative process caused by HIV," Mellgren said in a statement.
"This study confirms that neurofilament light protein serves as a useful marker in monitoring brain injury in people with HIV and in evaluating the effectiveness of HAART." - (Reuters Health)
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ART really lowers Aids risk
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