This article is more than 5 years old. Information may no longer be current.

Patients with HIV who smoke at greater risk for lung cancer mortality

Patients with HIV who adhere to antiretroviral therapy but smoke are significantly more likely to die from lung cancer than from AIDS-related causes; therefore, smoking cessation should be a priority in HIV care, according to research published in JAMA Internal Medicine.

“Lung cancer has become a leading cause of death among people living with HIV. Over 40% of [people living with HIV (PLWH)] in the United States smoke cigarettes,” Krishna P. Reddy, MD, from Massachusetts General Hospital, and colleagues wrote.

HIV independently increases lung cancer risk and thus, tobacco use and HIV together may accelerate its development, according to the researchers.

Reddy and colleagues sought to determine the relationship between smoking exposure and the risk for lung cancer mortality among individuals receiving care for HIV using a validated microsimulation model of HIV. Smoking exposure was defined as both smoking status (current, former or never) and intensity based on number of cigarettes per day (heavy, moderate or light). The researchers measured cumulative lung cancer mortality by age 80 years, stratifying by sex, age at entry into HIV care and smoking exposure. They also calculated total expected lung cancer deaths while accounting for nonadherence to antiretroviral therapy (ART).

In an analysis by gender, the risk ratio (RR) for lung cancer mortality was 23.6 for male current moderate smokers and 24.2 for female current moderate smokers compared with those who never smoked, and the RRs for those who quit smoking at age 40 years was 4.3 in men and 4.5 in women.

Among HIV-infected men aged 40 years, heavy continuous smoking resulted in an estimated cumulative lung cancer mortality of 28.9% compared with 23% for moderate continuous smoking and 18.8% for light continuous smoking. Similar discrepancies between groups were reported among former smokers who quit at age 40 years, with an estimated cumulative lung cancer mortality of 7.9% for heavy smokers, 6.1% for moderate smokers and 4.3% for light smokers compared with 1.6% for those who never smoked.

The corresponding mortality for women who were current smokers was 27.8% for heavy smokers, 20.9% for moderate smokers and 16.6% for light smokers, whereas for former smokers it was 7.5% for heavy smokers, 5.2% for moderate smokers and 3.7% for light smokers compared with 1.2% for those who never smoked.

In ART-adherent individuals who continued to smoke, the risk for death from lung cancer was six to 13 times greater than death from traditional AIDS-related causes. Incomplete ART adherence was associated with higher overall mortality but lower lung cancer mortality.

The researchers applied their model projections to the approximately 644,200 individuals living with HIV aged 20 to 64 years in the United States and estimated that 9.3% would die from lung cancer if they do not change their smoking habits.

“There is a large expected burden of lung cancer among [people living with HIV] in the United States ... Clinicians caring for PLWH should offer guideline-based behavioral and pharmacologic treatments for tobacco use,” Reddy and colleagues concluded. “Lung cancer is now a leading cause of death among PLWH, but smoking cessation can greatly reduce the risk. Lung cancer prevention, especially through smoking cessation, should be a priority in the comprehensive care of PLWH.” – by Alaina Tedesco

Disclosure: The researchers report no relevant financial disclosures.