Elevated Serum Free Light Chains Predict Cardiovascular Events in Type 2 Diabetes

Abstract

OBJECTIVE Elevated polyclonal serum immunoglobulin free light chains (FLCs; combined FLCκ+FLCλ [cFLC]) are associated with adverse clinical outcomes and increased mortality; we investigated cFLC and cardiovascular disease (CVD) events in type 2 diabetes. RESEARCH DESIGN AND METHODS In a cohort study of 352 south Asian patients with type 2 diabetes, serum cFLC, high-sensitivity C-reactive protein (hsCRP), and standard biochemistry were measured. CVD events over 2 years were recorded and assessed using multiple logistic regression. RESULTS cFLC levels were elevated significantly in 29 of 352 (8%) patients with CVD events during 2 years of follow-up (50.7 vs. 42.8 mg/L; P = 0.004). In multivariate analysis, elevated cFLC (>57.2 mg/L) was associated with CVD outcomes (odds ratio 3.3 [95% CI 1.3–8.2]; P = 0.012) and remained significant after adjusting for age, albumin-to-creatinine ratio, diabetes duration, or treatment. CONCLUSIONS cFLC elevation is a novel marker for CVD outcomes in type 2 diabetes that warrants further investigation.