title: Serum bilirubin levels are positively associated with glycemic variability in women with type 2 diabetes.
abstract: OBJECTIVE
  Glycemic variability is known to induce oxidative stress. We investigated the relationships between glycemic variability and serum bilirubin levels, an endogenous anti-oxidant, in patients with diabetes.
  
  
  METHODS
  A cross-sectional study was carried out with 77 patients with type 2 diabetes who had been recruited to two clinical studies from 2008 to 2014. There were no participants with diseases of the pancreas, liver, biliary tract and chronic renal insufficiency. Glycemic variation was calculated by a continuous glucose monitoring system, and correlation analyses were carried out to evaluate their association with bilirubin levels. Multiple linear regression was carried out to identify independent factors influencing bilirubin levels and glycemic variation.
  
  
  RESULTS
  Among the participants, 42.3% were men. The mean (standard deviation) age was 61.5 years (10.4 years), body mass index was 24.2 kg/m2(2.8 kg/m2), diabetes duration was 17.7 years (9.5 years), hemoglobin A1cwas 60.7 mmol/mol (7.1 mmol/mol; 7.7 [0.7]%) and bilirubin was 11.8 μmol/L (4.10 μmol/L). Serum bilirubin levels were not different according to age, body mass index and hemoglobin A1c. However, the mean amplitude of glucose excursion was positively associated with bilirubin levels in women (r = 0.588, P < 0.001). After adjustment with duration of diabetes, serum albumin, liver enzymes, and mean glucose, the correlation between bilirubin and mean amplitude of glucose excursion remained significant (r = 0.566, P < 0.001). Multiple linear regression analyses showed that bilirubin was an independent determinant for the mean amplitude of glucose excursion in women. 1,5-Anhydroglucitol was also associated with bilirubin levels in women.
  
  
  CONCLUSIONS
  Bilirubin level within the physiological range might be an independent predictor for glycemic variability in women with type 2 diabetes.
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Lee Kyung
authors.identifier: http://orcid.org/0000-0003-2376-1948
authors.initials: LK
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Eun
authors.initials: E
authors.lastname: Roh
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Min Joo
authors.initials: MJ
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Min Kyeong
authors.initials: MK
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Kyeong Seon
authors.initials: KS
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Soo Heon
authors.initials: SH
authors.lastname: Kwak
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Young Min
authors.initials: YM
authors.lastname: Cho
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Kyong Soo
authors.initials: KS
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Hak Chul
authors.initials: HC
authors.lastname: Jang
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea. junghs@snu.ac.kr.
authors.forename: Hye Seung
authors.initials: HS
authors.lastname: Jung
mesh_terms: D000368:Aged; D001663:Bilirubin / Q000097:blood*; D001786:Blood Glucose / Q000032:analysis / Q000378:metabolism*; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D012737:Sex Factors
chemical_list: D001786:Blood Glucose; D001663:Bilirubin
keywords: Bilirubin; Continuous glucose monitoring; Glucose variability