title: Elevated serum complement C3 levels are related to the development of prediabetes in an adult population: the Tianjin Chronic Low-Grade Systematic Inflammation and Health Cohort Study.
abstract: OBJECTIVE
  To investigate whether serum complement C3 is related to the prevalence and incidence of prediabetes in an adult population.
  
  
  METHODS
  A cross-sectional (n = 10 206) and prospective cohort study (n = 3333), with a mean (range; 95% CI) follow-up of 2.63 (1-6; 2.58-2.68) years, was conducted in people recruited from the Health Management Centre of Tianjin Medical University General Hospital in Tianjin, China. Measurement of serum C3 concentration, blood fasting glucose, oral glucose tolerance, HbA1c and other potential confounding factors was performed at baseline and each year during the follow-up. Prediabetes was defined according to the criteria of the American Diabetes Association. Adjusted logistic and Cox proportional hazards regression models were used to assess the relationships between C3 quintiles and prediabetes.
  
  
  RESULTS
  The prevalence and incidence of prediabetes were 38.5% and 119 per 1000 person-years, respectively. In cross-sectional analysis, after adjustment for potential confounders, the odds ratios of prediabetes for increasing quintiles of C3 were 1.00 (reference), 1.32 (95% CI 1.14-1.53), 1.37 (95% CI 1.18-1.59), 1.75 (95% CI 1.51-2.03), 2.25 (95% CI 1.93-2.62; P for trend < 0.0001). In the cohort analysis, the multiple-adjusted hazard ratio of prediabetes in the highest quintile of baseline C3 was 1.43 (95% CI 1.15, 1.78; P for trend < 0.001), when compared with the lowest quintile.
  
  
  CONCLUSIONS
  These findings indicate that elevated serum C3 levels are significantly related to an increased risk of developing prediabetes in an adult population, suggesting that C3 can be used as a biomarker in high-risk individuals to improve primary prevention of prediabetes and diabetes.
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China.
authors.forename: X
authors.initials: X
authors.lastname: Bao
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Xia
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China.
authors.forename: Q
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China.
authors.forename: H M
authors.initials: HM
authors.lastname: Wu
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China.
authors.forename: H M
authors.initials: HM
authors.lastname: Du
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China.
authors.forename: L
authors.initials: L
authors.lastname: Liu
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China.
authors.forename: C J
authors.initials: CJ
authors.lastname: Wang
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China.
authors.forename: H B
authors.initials: HB
authors.lastname: Shi
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China.
authors.forename: X Y
authors.initials: XY
authors.lastname: Guo
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China.
authors.forename: X
authors.initials: X
authors.lastname: Liu
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China.
authors.forename: C L
authors.initials: CL
authors.lastname: Li
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China.
authors.forename: Q
authors.initials: Q
authors.lastname: Su
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China.|Department of Toxicology, School of Public Health, Tianjin Medical University, Tianjin, China.
authors.forename: G
authors.initials: G
authors.lastname: Meng
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China.|Institute of Psychology, Tianjin Medical University, Tianjin, China.
authors.forename: B
authors.initials: B
authors.lastname: Yu
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China.
authors.forename: S M
authors.initials: SM
authors.lastname: Sun
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China.
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China.
authors.forename: M
authors.initials: M
authors.lastname: Zhou
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China.
authors.forename: Q Y
authors.initials: QY
authors.lastname: Jia
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China.
authors.forename: K
authors.initials: K
authors.lastname: Song
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China.|Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China.
authors.forename: K J
authors.initials: KJ
authors.lastname: Niu
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D002681:China / Q000453:epidemiology; D015331:Cohort Studies; D003176:Complement C3 / Q000032:analysis*; D003430:Cross-Sectional Studies; D005260:Female; D006785:Hospitals, University; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D011236:Prediabetic State / Q000097:blood / Q000453:epidemiology / Q000209:etiology* / Q000276:immunology; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D016019:Survival Analysis; D018746:Systemic Inflammatory Response Syndrome / Q000503:physiopathology*; D015854:Up-Regulation; D014504:Urban Health
chemical_list: D015415:Biomarkers; C038245:C3 protein, human; D003176:Complement C3