Background: We aimed to estimate the impact of comorbidity acquired before HIV diagnosis on mortality in individuals infected with HIV.
Methods: This cohort study compared 2 different cohorts. The prospective population-based nationwide observational Danish HIV Cohort Study was used to compare all adults diagnosed with HIV in Denmark from 1997 with a matched general population cohort. Comorbidity history was ascertained from the Danish National Patient Registry and vital statistics obtained from the Danish Civil Registration System. Cox regression was used to estimate the impact of Charlson comorbidity index (CCI) and hepatitis C virus coinfection on mortality, and population attributable risk was used to assess the proportional impact of comorbidity on mortality.
Results: CCI comorbidity was present before HIV diagnosis in 11.3% of 1638 persons with HIV, and in 8.0% of 156,506 persons in the general population. The risk for death in patients with HIV with at least 1 CCI point was 1.84 times higher than in those with no CCI points (adjusted mortality rate ratio, 95% confidence interval: 1.32 to 2.57). The annual risk of dying for patients with HIV vs general population with 0, 1, 2, and 3+ CCI points was 1.70% (1.44 to 2.00) vs 0.27% (0.26 to 0.28), 4.37% (3.01 to 6.32) vs 1.36% (1.26 to 1.47), 8.06% (4.94 to 13.16) vs 2.44% (2.22 to 2.68), and 10.15% (5.08 to 20.30) vs 5.84% (5.19 to 6.58), respectively. Comorbidity acquired before HIV, hepatitis C virus coinfection, and background mortality accounted for 45% of total mortality in the population infected with HIV.
Conclusions: Almost half of deaths in persons diagnosed with HIV in a health care setting with free access to highly active antiretroviral therapy stemmed from factors unrelated to HIV disease.