AIDS (London, England) 2017 12 12() doi 10.1097/QAD.0000000000001721
With combination-antiretroviral therapy, HIV-infected individuals live longer with an elevated burden of cancer. Given the high prevalence of smoking among HIV-infected populations, we examined the risk of incident cancers attributable to ever smoking cigarettes.
Observational cohort of HIV-infected participants with 270,136 person-years of follow-up in the North American AIDS Cohort Collaboration on Research and Design consortium. Among 52,441 participants; 2306 were diagnosed with cancer during 2000-2015.
MAIN OUTCOME MEASURES
Estimated hazard ratios (HR) and population-attributable fractions (PAF) associated with ever cigarette smoking for all cancers combined, smoking-related cancers, and cancers that were not attributed to smoking.
People with cancer were more frequently ever smokers (79%) compared to people without cancer (73%). Adjusting for demographic and clinical factors, cigarette smoking was associated with increased risk of cancer overall (HR = 1.33 [95% confidence interval: 1.18-1.49]); smoking-related cancers (HR = 2.31 [1.80-2.98]), lung cancer (HR = 17.80 [5.60-56.63]); but not non-smoking-related cancers (HR = 1.12 [0.98-1.28]). Adjusted PAFs associated with ever cigarette smoking were as follows: all cancers combined, PAF = 19% [95% confidence interval: 13%-25%]; smoking-related cancers, PAF = 50% [39%-59%]; lung cancer, PAF = 94% [82%-98%]; and non-smoking-related cancers, PAF = 9% [1%-16%].
Among HIV-infected persons, approximately one fifth of all incident cancer, including half of smoking-related cancer, and 94% of lung cancer diagnoses could potentially be prevented by eliminating cigarette smoking. Cigarette smoking could contribute to some cancers that were classified as non-smoking-related cancers in this report. Enhanced smoking cessation efforts targeted to HIV-infected individuals are needed.