Impact of Cigarette Smoking and Smoking Cessation on Life Expectancy Among People With HIV: A US-Based Modeling Study
Journal of Infectious Diseases December 1, 2016 V.214 N.11 P.1672-1681
Krishna P. Reddy, Robert A. Parker, Elena Losina, Travis P. Baggett, A. David Paltiel, Nancy A. Rigotti, Milton C. Weinstein, Kenneth A. Freedberg, and Rochelle P. Walensky
1Medical Practice Evaluation Center
2Division of Pulmonary and Critical Care Medicine
3Division of General Internal Medicine
5Tobacco Research and Treatment Center
6Mongan Institute for Health Policy
7Division of Infectious Diseases, Massachusetts General Hospital
8Harvard Medical School
9Department of Orthopedic Surgery
10Division of Infectious Diseases, Brigham and Women’s Hospital
11Department of Biostatistics
12Department of Epidemiology, Boston University School of Public Health
13Boston Health Care for the Homeless Program
14Department of Health Policy and Management, Harvard T. H. Chan School of Public Health, Boston, Massachusetts
15Yale School of Public Health, New Haven, Connecticut
In the United States, >40% of people infected with human immunodeficiency virus (HIV) smoke cigarettes.
We used a computer simulation of HIV disease and treatment to project the life expectancy of HIV-infected persons, based on smoking status. We used age- and sex-specific data on mortality, stratified by smoking status. The ratio of the non-AIDS-related mortality risk for current smokers versus that for never smokers was 2.8, and the ratio for former smokers versus never smokers was 1.0–1.8, depending on cessation age. Projected survival was based on smoking status, sex, and initial age. We also estimated the total potential life-years gained if a proportion of the approximately 248 000 HIV-infected US smokers quit smoking.
Men and women entering HIV care at age 40 years (mean CD4+ T-cell count, 360 cells/µL) who continued to smoke lost 6.7 years and 6.3 years of life expectancy, respectively, compared with never smokers; those who quit smoking upon entering care regained 5.7 years and 4.6 years, respectively. Factors associated with greater benefits from smoking cessation included younger age, higher initial CD4+ T-cell count, and complete adherence to antiretroviral therapy. Smoking cessation by 10%–25% of HIV-infected smokers could save approximately 106 000–265 000 years of life.
HIV-infected US smokers aged 40 years lose >6 years of life expectancy from smoking, possibly outweighing the loss from HIV infection itself. Smoking cessation should become a priority in HIV treatment programs.