High YKL-40 levels predict mortality in patients with type 2 diabetes

Aims: We determined levels of the inflammatory marker YKL-40 in a population of patients with type 2 diabetes (T2D) and investigated the association with mortality. Methods: In a prospective observational follow-up study, 290 patients with T2D, normoalbuminuria (n = 177), microalbuminuria (n = 71) and macroalbuminuria (n = 42) were followed for a median (range) of 17.2 (0.2-23.0) years. Serum YKL-40 concentration was determined at baseline. Results: Baseline median (IQR) YKL-40 level was 46 ng/ml (36-67) in patients with normoalbuminuria, 61 ng/ml (43-114) in microalbuminuric patients, and 81.5 ng/ml (60-157) in patients with macroalbuminuria, p < 0.001. During follow-up 189 patients (65.2%) died, 119 (41.0%) from cardiovascular causes. All-cause mortality was increased in patients with YKL-40 levels in the second and third tertile (hazard ratios (95% CI) compared with the first tertile, (1.50 (1.03-2.19), p = 0.034, and 2.88 (2.01-4.12), p < 0.001). This association persisted after adjustment for cardiovascular risk factors but was attenuated after additional adjustment for urinary albumin excretion rate and glomerular filtration rate. Cardiovascular mortality was increased with YKL-40 levels in the third tertile compared with the first tertile, (2.70 (1.78-4.08)), p < 0.001. This association was diminished after adjustment for covariates. Conclusions: In patients with T2D and increasing albuminuria high YKL-40 levels predict all-cause mortality. (C) 2011 Elsevier Ireland Ltd. All rights reserved.