MELBOURNE, Australia -- Although it has well-known psychiatric side effects, the HIV drug efavirenz (Sustiva) does not affect cognition, a researcher said here.
In a large case series, there was no increase in the risk of neurocognitive impairment among patients taking the drug, compared with those taking other anti-HIV medications, according to Andrea Antinori, MD, of the Italian in Rome.
Action Points
- Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
There was also no association between longer use of the drug and cognitive impairment, Antinori reported at the here.
The findings are reassuring, but won't change the concern over the emotional adverse effects of the drug, according to , of the Community Research Initiative of New England in Boston, who was not involved in the study.
The worry about efavirenz is the "impact of emotional disruption" caused by the drug -- an impact ranging from dizziness to vivid dreams to suicidal thoughts, Cohen told 51˶.
That emotional disruption is the main reason patients stop taking efavirenz and it has "nothing to do with whether I can remember 16 different tasks," he said.
Efavirenz, a non-nucleoside reverse transcriptase inhibitor, is the basis of a preferred triple-drug regimen and is part of a widely used single-pill regimen marketed as Atripla.
The neuropsychiatric side effects have been well known since the drug was approved, but the question of whether it also impaired cognition has been controversial, Antinori said.
To help settle the issue, he and colleagues reviewed 1,020 consecutive neuropsychological assessments of 859 patients, including 325 taking efavirenz,
They were given 14 standardized tests evaluating five domains -- concentration and speed of mental processing, memory, flexibility, fine motor functioning, and visuospatial abilities.
Efavirenz patients were significantly more likely to be male, to be men who have sex with men, and to have an undetectable viral load at the time of the assessment, Antinori said.
They were less likely to have hepatitis C, low hemoglobin, or to have an AIDS-defining illness, he added.
Overall, he and colleagues found, 382 patients were defined as impaired -- they were at least one standard deviation below the normal mean on two tests or at least two standard deviations low on one or more tests.
The proportion of impairment among efavirenz patients was 32.1%, compared with 39.9% among those not on the drug, he reported.
After adjustment for such things as age, years of education, AIDS, other drugs in the regimen, and the calendar year of the assessment, the difference was not significant, Antinori reported.
When the researchers looked at each of the neurocognitive domains separately, there was also no significant effect of taking efavirenz, Antinori reported.
The median exposure to efavirenz among patients in the study was 30 months, but there was no association between impairment and longer exposure, Antinori reported.
He cautioned that it's possible that concern about the potential for cognitive impairment caused physicians to steer some patients away from efavirenz, a so-called channeling bias.
As well, other unmeasured factors, such as adherence to medication, might have affected the results, he said. The researchers controlled for major depression, he added, but not all patients underwent a systematic assessment of depression.
Disclosures
Antinori did not report external support for the study. He disclosed relationships with AbbVie, Bristol Myers Squibb, Gilead, Janssen, Merck, and ViiV.
Cohen has disclosed relationships with Bristol-Myers Squibb, Janssen Pharmaceuticals, Merck, and ViiV.