Hepatitis C virus (HCV) RNA loads are measured sporadically in HCV-positive individuals. However, the prognostic value of these isolated measurements for predicting progression to acquired immune deficiency syndrome (AIDS) and all-cause mortality in coinfected individuals remains unclear. In this study, the prognostic value of a single HCV RNA load measurement taken early after human immunodeficiency virus (HIV) seroconversion was investigated in a cohort of 96 male patients with inherited bleeding disorders. Dates of HIV seroconversion had been estimated for all patients, and at least 4 HCV RNA load measurements per patient were done retrospectively after HIV seroconversion. HCV RNA load stabilized at 4 years after HIV seroconversion, and this point was used for analysis. There was a significant correlation between increased age and early HCV RNA load (r=0.25; P=.01). Adjusting for HIV RNA levels, CD4 cell counts, and the age effect, HCV RNA load >5.90 log(10) copies/mL was predictive of progression to AIDS and all-cause mortality over a period of at least 15 years.