HIV-infected men with an elevated level of serum cystatin C have a high likelihood of developing cancers

Abstract

Background: HIV-infected individuals are at high risk for morbidity and mortality regardless of good infection control with highly active antiretroviral therapy (HAART). The residual inflammation after apparent good infection control with HAART may be responsible for an increased risk of mortality including cancers. Serum cystatin C is not only a sensitive marker for renal dysfunction but also a potential marker for inflammation, which may suggest that this marker is something more than a measure of renal function. Materials and methods: A total of 520 HIV-infected men under good infection control with HAART were enrolled in a 3-year prospective cohort study. The incidence of cancers was investigated with special reference to serum cystatin C level. Cumulative incidence of cancers over time was analyzed by Kaplan-Meier methods. A Cox proportional hazards model was used to calculate the Hazard Ratio (HR) of developing cancers, adjusted for age, smoking habit, CD4 cell count, serum albumin, estimated glomerular filtration rate below 60 mL/min/1.73m2, C-reactive protein, and presence of comorbidities including diabetes mellitus, hypertension, and hepatic viral infection. Results: During the follow-up, cancers developed in 14 (2.7%) subjects. Death occurred in 4 from cancers. The Kaplan-Meier estimate for cancer incidence significantly increased in patients with serum cystatin C elevation (≥ 1.0 mg/L). The HR (95% confidence interval) of cancer incidence was 3.56 (1.08-11.2) for elevation of serum cystatin C, although other markers of inflammation were not significant. Conclusion: The examination of serum cystatin C may enable earlier recognition of cancers among HIVinfected individuals. © 2012 Yanagisawa N, et al.