Effect of early and late GB virus C viraemia on survival of HIV-infected individuals: a meta-analysis.
OBJECTIVE
To conduct a meta-analysis to synthesize the evidence regarding the effect of co-infection with GB virus C (GBV-C) on survival of HIV-infected individuals, and to estimate the effect.


METHODS
A Bayesian meta-analysis was conducted to synthesize evidence from eligible studies. Prospective survival studies of HIV-1-infected individuals, with outcome defined as time from baseline to all-cause death, were included and classified by whether GBV-C status was determined in early or late HIV disease. The primary measure was the hazard ratio (HR) of death for HIV-infected individuals with GBV-C infection versus those without GBV-C infection.


RESULTS
Eleven studies from eight publications met the inclusion criteria. For studies with GBV-C status measured 2 years or less after HIV seroconversion (912 subjects), the combined HR was 0.88 [95% credible interval (CI) 0.30, 1.50]. For studies with GBV-C status measured more than 2 years after HIV seroconversion (1294 subjects), the combined HR was 0.41 (95% CI 0.23, 0.69).


CONCLUSIONS
No conclusive evidence was found of an association between survival and GBV-C infection early in HIV disease. However, when GBV-C infection was present later in HIV disease, a significant reduction in the hazard for mortality was observed for those with co-infection. Potential explanations for this difference include a non-proportional benefit of GBV-C over time, possibly related to clearance of GBV-C infection early in HIV disease. The timing of GBV-C infection appears to account for the contradictory results of studies on the effect of GBV-C coinfection on survival of HIV-infected people.
Department of Biostatistics, College of Public Health, University of Iowa, Iowa City, IA 52242, USA.
W
W
Zhang
K
K
Chaloner
H L
HL
Tillmann
C F
CF
Williams
J T
JT
Stapleton
D000328:Adult; D001499:Bayes Theorem; D005260:Female; D018178:Flaviviridae Infections / Q000401:mortality / Q000821:virology*; D029407:GB virus C; D015658:HIV Infections / Q000401:mortality / Q000821:virology*; D006679:HIV Seropositivity; D015497:HIV-1; D006525:Hepatitis, Viral, Human / Q000401:mortality / Q000821:virology*; D006801:Humans; D008297:Male; D016016:Proportional Hazards Models; D015996:Survival Rate; D013997:Time Factors; D019562:Viral Load; D014766:Viremia