Smoking marijuana does not lead to poorer adherence to HAART in patients with mild to severe nausea caused by anti-HIV drugs, according to a study published in the January 1st edition of the Journal of Acquired Immune Deficiency Syndromes. However, the US investigators found that the use of other illicit drugs, and the smoking of marijuana by patients with no or mild nausea, was associated with non-adherence to HAART.
Marijuana is used by some HIV-positive individuals to stimulate appetite and to counter nausea caused by HAART. Nevertheless, there are concerns about the safety of marijuana use, not least the potential for use of the drug to decrease adherence to HAART due to its psychoactive effects.
It has been shown that the use of other illicit drugs, including heroin, cocaine and speed and decrease adherence to HAART, and two studies published in 2003 found that marijuana use had a similar affect. However, as marijuana is often used by HIV-positive patients to relieve symptoms or side-effects, investigators postulated that use of the drug might not be associated with poor adherence in patients taking HAART who are experiencing adverse events including nausea.
Investigators recruited 252 HIV-positive patients from three HIV clinics in Northern California to their study in 2001. They were asked to report their adherence to HAART in the previous week. Patients who missed at least one dose were assessed as “non-adherent.” Individuals were also asked to say if they had ever used marijuana and to report the use of marijuana, and any other illicit substances, in the past four weeks.
Of the 252 patients who completed the study questionnaire, 168 (67%) provided data about their adherence to HAART. In total 41 individuals (24%), said that they had used marijuana in the previous four weeks.
A third of patients taking HAART (55 individuals) were assessed as non-adherent. In bivariate analysis, the investigators failed to find any positive or negative association between marijuana use and adherence (OR 0.92). Adherence was associated with a viral load below 50 copies/ml (p = 0.04) and having had mental distress about one’s health (p = 0.04). Adherence was negatively associated with use of illicit drugs other than marijuana in the last four weeks (p = 0.02) and with alcohol use in the last four weeks (p = 0.04).
The investigators then looked at the subgroup of patients reporting moderate to severe nausea (43 individuals). Of the 20 patients who used marijuana, 75% were assessed as being adherent compared to 48% of the 23 patients who did not report use of the drug (p = 0.07).
However, when the investigators looked at the 125 patients with no or mild nausea, they found that marijuana users were significantly less likely to be adherent than non-users (p = 0.02).
“No crude association was found between marijuana use and adherence”, write the investigators, who add, “our data do suggest that use of smoked marijuana specifically to ameliorate nausea may be associated with adherence to antiretroviral therapy…in addition, our data confirm previously reported findings that the use of other illicit drugs is associated with lower rates of adherence”.
The investigators note that the use of marijuana for medical purposes remains controversial and “do not here advocate its widespread use…however, in certain circumstances, specifically when patients are using marijuana to relieve nausea, marijuana is not associated with lower rates of adherence.”
de Jong BC et al. Marijuana use and its association with adherence to antiretroviral therapy among HIV-infected persons with moderate to severe nausea. J Acquir Immune Defic Syndr 38: 43 – 46, 2005.