title: C-peptide predicts the remission of type 2 diabetes after bariatric surgery.
abstract: BACKGROUND
  C-peptide is a surrogate of the pancreatic beta cell mass. However, the clinical significance of C-peptide in a diabetic patient after bariatric surgery has not been studied clearly.
  
  
  METHODS
  From February 2005 to January 2009, a total of 205 (124 females and 81 males) consecutive morbidly obese patients with type 2 diabetes mellitus (T2DM) enrolled in a surgically supervised weight loss program with at least 1 year follow-up were examined. Among them, 147 patients (71.7%) received gastric bypass procedures, while the other 58 patients (28.3%) received restrictive-type procedures.
  
  
  RESULTS
  The mean C-peptide before the surgery was 5.3 ± 3.5 ng/ml. One hundred nineteen patients (58.0%) had an elevated C-peptide (>4 ng/ml), while 2 patients (1.0%) had a low C-peptide (<1.0 ng/ml). Multivariate analysis confirmed that waist circumference, triglycerides, and HbA1c were the independent predictors for the elevation of C-peptide. It was observed that the mean C-peptide levels decreased to 1.7 ± 0.9 ng/ml 1 year after bariatric surgery with a mean reduction of 64.1%. One year after surgery, 160 patients (78.0%) out of a total of 205 patients had a remission of their T2DM. Patients in the bypass group had a higher diabetes remission rate (91.2%; 134 out of 147) in comparison to patients in the restrictive group (44.8%; 26 out of 58, p < 0.001). The diabetes remission rates for those with preoperative C-peptide <3, 3-6, and > 6 ng/ml were 26 out of 47 (55.3%), 87 out of 108 (82.0%), and 47 out of 52 (90.3%), p < 0.001, respectively.
  
  
  CONCLUSIONS
  Baseline C-peptide is commonly elevated in morbidly obese patients with T2DM. There was a marked reduction in C-peptide after a significant weight reduction 1 year after surgery with a T2DM remission rate of 78.0%. Thus, bariatric surgery is recommended for obesity-related T2DM patients with elevated C-peptide.
authors.affiliation: Department of Surgery, Min-Sheng General Hospital, No. 168, Chin Kuo Road, Tauoyan, Taiwan, Republic of China. wjlee_obessurg_tw@yahoo.com.tw
authors.forename: Wei-Jei
authors.initials: WJ
authors.lastname: Lee
authors.forename: Keong
authors.initials: K
authors.lastname: Chong
authors.forename: Kong-Han
authors.initials: KH
authors.lastname: Ser
authors.forename: Jung-Chien
authors.initials: JC
authors.lastname: Chen
authors.forename: Yi-Chih
authors.initials: YC
authors.lastname: Lee
authors.forename: Shu-Chun
authors.initials: SC
authors.lastname: Chen
authors.forename: Yen-How
authors.initials: YH
authors.lastname: Su
authors.forename: Min-Han
authors.initials: MH
authors.lastname: Tsai
mesh_terms: D000293:Adolescent; D000328:Adult; D050110:Bariatric Surgery; D015992:Body Mass Index; D002096:C-Peptide / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000209:etiology / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000097:blood / Q000150:complications / Q000601:surgery*; D011237:Predictive Value of Tests; D012074:Remission Induction; D016896:Treatment Outcome; D015431:Weight Loss; D055815:Young Adult
chemical_list: D002096:C-Peptide