With more than four in 10 people living with HIV in the United States hooked on cigarettes, members of this population face dire prospects of dying of lung cancer. Those who adhere well to antiretroviral (ARV) treatment for the virus but smoke are estimated to have a more than 10 times greater chance of dying of lung cancer compared with dying of AIDS-related complications.

Previous research from Danish investigators memorably published in 2012 found that, overall, HIV-positive smokers lose far more years of life to cigarettes than to the virus. People with HIV who smoke lose 12 years of life compared with their nonsmoking peers, those scientists estimated. This new study narrows the range of such an inquiry, focusing solely on projected lung cancer deaths.

Publishing their findings in JAMA Internal Medicine, researchers at Massachusetts General Hospital (MGH) used computer simulation models of HIV to estimate the risk of lung cancer among the U.S. population living with the virus. They included in their model whether individuals are current, former or never smokers, their current or former cigarette-per-day smoking rate and whether they were adherent to their daily ARV regimen.

The study authors projected that 25 percent of people with HIV who smoke and are adherent to their ARVs will die of lung cancer, a figure that rises closer to 30 percent when it comes to heavy smokers. Among those smokers who quit when they are 40 years old, only a projected 6 percent will die of the malignancy. Depending on their cigarette-per-day smoking rate and their sex, smokers who are adherent to their HIV meds are an estimated six to 13 times more likely to die of lung cancer than AIDS-related complications. Even among smokers who adhere poorly to their ARVs, an estimated 15 percent will die of lung cancer.

The researchers also estimated that of all those currently in care for HIV in the United States, about one in 10, or nearly 60,000, will die of lung cancer, including both those who do and do not smoke.

“Lung cancer is now one of the leading killers of people with HIV, but most of these deaths can be prevented,” Rochelle Walensky, MD, MPH, chief of the MGH Division of Infectious Disease and a senior author of the study, said in a press release.

“Quitting smoking is one of the most important things that people with HIV can do to improve their health and live longer, Travis Baggett, MD, MPH, of the MGH Division of General Internal Medicine and coauthor of the study, said in the same press release. “Quitting will not only reduce their risk of lung cancer but also decrease their risk of many other diseases, such as heart attack, stroke and emphysema.”

To read a press release about the study, click here.