Mortality Attributable to Smoking Among HIV-1–Infected Individuals: A Nationwide, Population-Based Cohort Study

BACKGROUND: We assessed mortality attributable to smoking among patients with human immunodeficiency virus (HIV). METHODS: We estimated mortality rates (MRs), mortality rate ratios (MRRs), life expectancies, life-years lost, and population-attributable risk of death associated with smoking and with HIV among current and nonsmoking individuals from a population-based, nationwide HIV cohort and a cohort of matched HIV-negative individuals. RESULTS: A total of 2921 HIV patients and 10 642 controls were followed for 14 281 and 45 122 person-years, respectively. All-cause and non-AIDS-related mortality was substantially increased among smoking compared to nonsmoking HIV patients (MRR, 4. 4 95% confidence interval CI, 3. 0-6. 7 and 5. 3 95% CI, 3. 2-8. 8, respectively). Excess MR per 1000 person-years among current vs nonsmokers was 17. 6 (95% CI, 13. 3-21. 9) for HIV patients and 4. 8 (95% CI, 3. 2-6. 4) for controls. A 35-year-old HIV patient had a median life expectancy of 62. 6 years (95% CI, 59. 9-64. 6) for smokers and 78. 4 years (95% CI, 70. 8-84. 0) for nonsmokers; the numbers of life-years lost in association with smoking and HIV were 12. 3 (95% CI, 8. 1-16. 4) and 5. 1 (95% CI, 1. 6-8. 5). The population-attributable risk of death associated with smoking was 61. 5% among HIV patients and 34. 2% among controls. CONCLUSIONS: In a setting where HIV care is well organized and antiretroviral therapy is free of charge, HIV-infected smokers lose more life-years to smoking than to HIV. The excess mortality of smokers is tripled and the population-attributable risk of death associated with smoking is doubled among HIV patients compared to the background population.