Meta-analysis: insulin resistance and sustained virological response in hepatitis C

Background A higher baseline homeostasis model assessment of insulin resistance (HOMA-IR) score has sometimes predicted a poorer sustained virological response (SVR) rate to peginterferon/ribavirin therapy in treatment-naive chronic hepatitis C patients. Aim To perform a meta-analysis to evaluate the impact of HOMA-IR on SVR in hepatitis C. Methods Relevant studies were identified by searching Medline and EMBASE. We identified 17 publications that addressed the influence of insulin resistance on SVR. The random effect model of Der Simonian and Laird method were used for heterogeneous studies using the Meta-Disc software 1.4, Madrid, Spain. Results Normal insulin sensitivity was associated with a higher rate of SVR [odds ratio (OR) 2.86 (95% CI: 1.97-4.16)] in comparison with insulin resistance. Moreover, in separate analysis by genotype selecting studies that used HOMA-IR > 2 as cut-off defining insulin resistance, SVR was higher in patients with HOMA-IR < 2 in all genotypes: HCV-1 [OR: 2.16 (95% CI: 1.51-3.08)], HCV-2& 3 [OR: 3.06 (95% CI: 1.06-8.82)] and HCV-4 [OR: 6.65(95% CI: 2.51-17.61)]. Studies reporting no association between HOMA and SVR included easy-to-cure cohorts, analysed variables strongly related with insulin resistance like body mass index, steatosis, hyper gamma GT, age and fibrosis and reported differences in handling and interpretation of HOMA-IR. Conclusion Elevated HOMA-IR was associated with a lower cure rate of patients with hepatitis C treated with Peg-IFN-alpha/ribavirin irrespective of genotype, and the more difficult-to-treat cohort, the better the HOMA-IR prediction. HOMA-IR is, as a surrogate marker of insulin resistance, susceptible to some biases derived from both handling and interpretation.