title: Serum β-2 microglobulin predicts mortality in people with diabetes.
abstract: OBJECTIVE
  Serum β-2 microglobulin (B2M) level predicts mortality in chronic kidney disease. Glycation of B2M is cytotoxic and may contribute to the risk of mortality in diabetic patients. Our objective was to evaluate the relationship between B2M and mortality in diabetic patients.
  
  
  METHODS
  In this prospective study, 896 participants of the Third National Health and Nutrition Examination Survey with diabetes were included in the analysis. Serum B2M level was used in multivariate Cox regression analysis to predict all-cause and diabetes-related mortality.
  
  
  RESULTS
  During a median follow-up of 11.8 years (range 0.1-18.2 years) and 9220.5 person/years, 541 (42.4%) and 207 (16.8%) participants died from all causes and diabetes-related causes respectively. One natural-log unit of B2M was significantly associated with all-cause (hazard ratio (HR)=6.53, 95% CI 2.07-20.6) and diabetes mortality (HR=7.35, 95% CI 1.01-53.38) after multivariable adjustment. Similar results were obtained when B2M was analyzed as tertiles or in the threshold model (T1+T2 vs. T3). Examination of regression splines suggests a linear increase in hazard for mortality with increasing B2M levels.
  
  
  CONCLUSIONS
  Serum B2M level is a novel predictor of all-cause and diabetes-related mortality in people with diabetes regardless of renal function.
authors.affiliation: Division of Clinical Pharmacology and Therapeutics, The University of Hong Kong, Pokfulam, Hong Kong, China.
authors.forename: Ching-Lung
authors.initials: CL
authors.lastname: Cheung
authors.forename: Karen S L
authors.initials: KS
authors.lastname: Lam
authors.forename: Bernard M Y
authors.initials: BM
authors.lastname: Cheung
mesh_terms: D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data; D000368:Aged; D015415:Biomarkers / Q000097:blood; D003920:Diabetes Mellitus / Q000097:blood* / Q000401:mortality*; D003928:Diabetic Nephropathies / Q000097:blood / Q000401:mortality; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D016014:Linear Models; D008297:Male; D017058:Mexican Americans / Q000706:statistics & numerical data; D008875:Middle Aged; D009749:Nutrition Surveys; D016017:Odds Ratio; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D014481:United States / Q000453:epidemiology; D044465:White People / Q000706:statistics & numerical data; D001613:beta 2-Microglobulin / Q000097:blood*
chemical_list: D015415:Biomarkers; D001613:beta 2-Microglobulin