title: Metformin reduces serum CA199 levels in type 2 diabetes Chinese patients with time-effect and gender difference.
abstract: BACKGROUND
  This study was designed to clarify the influence of metformin on serum carbohydrate antigen 199 (CA199) levels and its associated factors in Chinese type 2 diabetes mellitus (T2DM) patients.
  
  
  METHODS
  In total, 1,253 T2DM patients were enrolled, including a non-metformin group (n = 616), a short-term metformin group (at least 1 week to 2 years; n=325), and a long-term metformin group (≥ 2 years; n = 312). Their clinical and biochemical characteristics were collected and compared. After 1 year, the biochemical parameters were re-examined in 296 patients. Sex hormones were determined, and associations between CA199 and other variables were assessed.
  
  
  RESULTS
  At baseline, the incidence of abnormal CA199 levels was 14.7%, 8.9%, and 4.7% in the non-metformin, short-term metformin, and long-term metformin groups, respectively. CA199 levels in females were significantly higher than in males (P < 0.01) and decreased significantly with the time of taking metformin (25.60 ± 13.68 U/mL in non-metformin controls vs. 17.62 ± 10.87 U/mL in the short-term group vs. 10.54 ± 8.14 U/mL in the long-term group; P = 0.000). The correlation and multiple stepwise regression analysis revealed that glycosylated hemoglobin, metformin, gender, total cholesterol, and follicle-stimulating hormone were independent impact factors on CA199 concentrations (all P < 0.05). Binary logistic regression revealed that the risk of abnormal CA199 concentrations of the total population with short-term metformin or long-term metformin treatment decreased 11% (odds ratio = 0.89; P = 0.001) and 30% (odds ratio = 0.70; P = 0.000), respectively, at baseline. After a 1-year follow-up, the incidence of high CA199 level decreased in both the short-term and the long-term metformin group compared with that of controls (P < 0.05). The extent of CA199 decrease in the long-term metformin group was the greatest (-17% vs. -4.9% in the short-term group vs. 3% in controls, P = 0.000), and the group's risk of high blood CA199 level was reduced 67% (odds ratio = 0.33; P = 0.023). The reduction in women was more apparent than that in men (-18% vs. -5%, P = 0.000).
  
  
  CONCLUSIONS
  Metformin therapy reduced the CA199 level in Chinese T2DM patients, and its greatest decrease occurred in women with longer therapeutic time.
authors.affiliation: Department of Endocrinology and Metabolism, Shanghai Jiaotong University Affiliated Sixth People's Hospital , Shanghai, China .
authors.forename: Dandan
authors.initials: D
authors.lastname: Zhang
authors.forename: Wolin
authors.initials: W
authors.lastname: Hou
authors.forename: Fang
authors.initials: F
authors.lastname: Liu
authors.forename: Jun
authors.initials: J
authors.lastname: Yin
authors.forename: Wei
authors.initials: W
authors.lastname: Lu
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Taishan
authors.initials: T
authors.lastname: Zheng
authors.forename: Fengdi
authors.initials: F
authors.lastname: Lu
authors.forename: Yuqian
authors.initials: Y
authors.lastname: Bao
authors.forename: Weiping
authors.initials: W
authors.lastname: Jia
mesh_terms: D044466:Asian People / Q000706:statistics & numerical data*; D001786:Blood Glucose / Q000187:drug effects* / Q000378:metabolism; D018395:CA-19-9 Antigen / Q000097:blood / Q000187:drug effects*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications / Q000188:drug therapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D008297:Male; D008687:Metformin / Q000627:therapeutic use*; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000150:complications* / Q000188:drug therapy; D012307:Risk Factors; D017678:Sex Distribution
chemical_list: D001786:Blood Glucose; D018395:CA-19-9 Antigen; D007004:Hypoglycemic Agents; D008687:Metformin