Introduction:
Hepatitis C (HCV) infection adversely affects survival among people living with HIV, increasing mortality risk due to liver-related causes. In Poland HCV is found among ~30% of HIV infected individuals, with only a small percentage successfully treated for this coinfection. This study aimed to analyze the HCV-associated influence on the life expectancy among HIV/HCV coinfected patients from northwestern Poland.

Material and methods:
Longitudinal data of 701 (368 HIV monoinfected and 368 HIV/HCV coinfected) patients were investigated to assess the life expectancy and survival after HIV diagnosis. Kaplan-Meier and Cox analyses were used to assess the mortality risk in both unadjusted and multivariate models. Effect plots indicate the adjusted hazard ratio for HCV-associated survival.

Results:
Overall mortality was significantly higher among HCV coinfected (22.52%) compared to HIV monoinfected (10.32%) cases (p < 0.001, OR = 2.52 (95% CI: 1.65–3.85)), with shorter life expectancy among HIV/HCV infected patients (median: 55.4 (IQR: 42.8–59.1) years) compared to HIV monoinfection (median 72.7 (IQR: 60.4–76.8) years, univariate HR = 4.15 (95% CI: 2.7–6.38), p < 0.0001, adjusted HR = 2.32 (95% CI: 1.47–3.65), p < 0.0001). After HIV diagnosis, HCV adversely influenced the survival after 15 years of follow-up, with a strengthened impact in the subsequent 5 years (univariate HR = 1.57 (95% CI: 1.05–2.34) p = 0.026 for the 20-year survival time point, adjusted HR = 2.21 (95% CI: 1.18–4.13), p = 0.013).

Conclusions:
Among patients living with HIV, HCV coinfection is associated with a median life expectancy decrease of 17.3 years and low probability of surviving until the age of 65 years. In the era of directly acting anti-HCV drugs, treatment scale-up and immediacy of treatment are advisable in this cohort.