Incidence and risk factors for weight loss during dual HIV/hepatitis C virus therapy.

BACKGROUND: Clinical observations suggest that patients with HIV/hepatitis C virus (HCV) may lose body weight during dual therapy, but this has not been confirmed analytically.

OBJECTIVES: To determine if the incidence and degree of weight loss among patients with HIV/HCV receiving highly active antiretroviral therapy (HAART) and pegylated (PEG)-interferon plus ribavirin were greater than in (1) HCV-monoinfected patients receiving PEG-interferon plus ribavirin and (2) HIV-monoinfected patients receiving HAART. Risk factors for weight loss among patients with HIV/HCV were also examined.

METHODS: A retrospective cohort study was performed among HIV/HCV-coinfected, HCV-monoinfected, and HIV-monoinfected patients. Body weights were assessed up to 6 months before and up to 12 months after initiation of HCV therapy (HIV/HCV-coinfected and HCV-monoinfected subjects) and over 18 months on HAART (HIV-monoinfected subjects). The primary outcome was clinically significant weight loss (> or =5% of baseline weight).

RESULTS: Of 192 subjects, 63 had HIV/HCV, 64 had HCV alone, and 65 had HIV alone. Clinically significant weight loss occurred in 48 (76%) subjects with HIV/HCV versus 25 (39%) subjects with HCV (P < 0.001) and 2 (3%) subjects with HIV (P < 0.001), yielding adjusted hazard ratios (HRs) of 2.76 (95% confidence interval [CI]: 1.67 to 4.55) and 38.5 (95% CI: 8.5 to 174.7), respectively. Receipt of more than 2 nucleoside reverse transcriptase inhibitors increased the risk of clinically significant weight loss (adjusted HR = 8.17, 95% CI: 2.37 to 28.20).

CONCLUSIONS: The incidence of weight loss is greater in dually treated patients with HIV/HCV than in treated HCV- or HIV-monoinfected patients. Prospective studies should evaluate additional risk factors for weight loss and changes in body composition to elucidate the mechanism for this weight loss.