Long-term smokers have higher rates of emphysema, or airway obstruction, in middle age if they are living with HIV, aidsmap reports.

Publishing their findings in the journal AIDS, researchers conducted a case-controlled study of 351 HIV-positive participants in the ANRS EP48 HIV CHEST study, comparing them with 702 age- and sex-matched HIV-negative controls in the CONSTANCES cohort.

The study’s inclusion criteria included being age 40 or older, having smoked the equivalent of a 20-year pack-a-day habit (known as 20 pack-years), having had a lowest-ever CD4 count below 350 and having a current CD4 count above 100. All study members were current smokers or people who had quit the habit within the previous three years. The study did not include individuals who had experienced a lung infection during the previous two months.

The participants had smoked for a median of 30 pack-years. Ninety-one percent of the HIV-positive individuals were current smokers, as were 67 percent of the HIV-negative individuals. Eighty-nine percent of the HIV-positive group had a fully suppressed viral load, and the overall group’s median current CD4 count was 573.

The HIV group had poorer lung function compared with the control group. Nineteen percent of those living with HIV experienced airway obstruction, compared with 9 percent of the controls.

After adjusting the data for various factors, the researchers found that HIV was associated with a  1.72-fold increased risk of airway obstruction. Each additional 10 years in age and each additional five pack-years of smoking were associated with a respective 1.77-fold and 1.11-fold increased risk of airway obstruction.

To read the aidsmap article, click here.

To read the study abstract, click here.