Regular Cannabis Use Reduces Volume of Virus in HIV Patients
Through THC signaling, cannabis is able to slow the multiplication of HIV, thus improving life expectancy outcomes for patients with AIDS.
Statistically speaking, illicit drug use is common in HIV populations. This is particularly detrimental to providing effective care, since it has been shown that illicit drug use is associated with decreased initiation of antiviral therapy and increased mortality. Morphine, for example, has been found to promote the replication of HIV-1 virus in human cultured cells extracted from the blood, and it did so in a the higher the dose of morphine, the more HIV-1 replication. Also, in a preclinical model of infection with a retrovirus (the same class of viruses to which HIV belongs), sustained cocaine use resulted in reduced immune functioning. Does cannabis, a non-illicit medicine in many parts of the world, have any of the same concerns?
People living with HIV/AIDS reportedly use cannabis to alleviate the side-effects of anti-retroviral therapy, including fever, nausea and vomiting. Recently, the potential for cannabis to improve HIV disease parameters has been explored. This research originated from the previously published pre-clinical studies showing immunomodulatory, anti-emetic and anti-inflammatory effects of cannabinoids. One particular study showed that administration of THC to monkeys carrying a simian immunodeficiency virus infection reduced plasma viral loads, which increased life span. In other words, THC signaling appears to have halted the multiplication of the virus which curbed the infection and the improved accompanying symptoms.
When researchers from Vancouver discovered this effect of THC, they wondered whether the same could be observed in humans living with HIV: can the plasma viral loads be reduced in people who used medical cannabis? This would translate to a significant reduction in their morbidity and mortality. Researchers found that daily cannabis use reduced plasma viral load significantly, compared to people who used cannabis at a lower frequency. Cannabinoids can modulate viral replication via indirect or direct effects. Namely, cannabinoids can bind to their receptors and exert immunomodulatory and anti-inflammatory effects.
HIV is known to induce a chronic inflammatory state which has been correlated with increased viral replication driven by pro-inflammatory mediators released by immune cells. Therefore, the anti-inflammatory properties of cannabinoids are expected to create unfavourable conditions for the virus to multiply, thus decreasing plasma viral loads. The evidence for a direct antiviral effect of cannabinoids has been shown by administration of a cannabinoid receptor agonist. Researchers found that it significantly suppressed replication of the HIV virus in microglia, which is a major nervous system cell type actively infected in human cases.
The full spectrum of virological and immunological effects of cannabis for people living with HIV/AIDS still remains to be described. However, the starting point has been identified and some evidence of anti-viral therapeutic potential is promising. There has been some concern in the scientific community about whether cannabis use would compromise adherence to anti-retroviral therapy in people living with this condition, which is imperative for reducing morbidity and mortality. However, it has been shown recently that daily cannabis use did not negatively affect adherence to anti-retroviral therapy. So far, the evidence points to the potential beneficial combinatorial therapy for people living with HIV/AIDS, consisting of anti-retroviral medication and daily cannabis use.