Among men who have sex with men (MSM) living with HIV, smoking marijuana is associated with a higher risk of both infectious and noninfectious lung diseases.
Publishing their findings in EClinicalMedicine, researchers studied 1996 to 2014 data on men from the Multicenter AIDS Cohort Study (MACS), a long-term observational cohort of HIV-positive and HIV-negative MSM. Participants eligible for this particular prospective cohort study were 30 years old or older and had provided self-reported data on marijuana and tobacco smoking during biannual study visits.
The study included 1,352 HIV-positive men who were matched with the same number of HIV-negative men according to race and the age at which they entered the study. Between them, the cohort members made 53,794 study visits and were followed for a median of 10.5 years.
Twenty-seven percent of the HIV-positive men and 18 percent of the HIV-negative men reported smoking marijuana daily or weekly during one or more years of follow-up, for use that lasted for a median of 4.0 and 4.5 years, respectively.
The cohort members received 1,630 diagnoses of lung diseases during follow-up. A total of 33.2 percent of the HIV-positive men and 21.5 percent of the HIV-negative men were diagnosed with infectious lung disease, and a respective 20.6 percent and 17.2 percent were diagnosed with noninfectious lung disease.
Among the men living with HIV, recent marijuana smoking was associated with a 43 percent higher risk of infectious lung disease and a 54 percent higher risk of noninfectious lung disease independent of tobacco smoking and other risk factors for lung disease. When HIV-positive men smoked both marijuana and tobacco, these risks were higher.
There was no association between recent marijuana smoking and lung disease risk among the HIV-negative men.
The study’s strength included its large sample size, the high number of lung diagnoses and the lenghty follow-up time.
“These findings could be used to reduce modifiable risks of lung disease in high-risk populations,” the study authors concluded.
To read the study, click here.