title: Smoking affects the oral glucose tolerance test profile and the relationship between glucose and HbA1c in gestational diabetes mellitus.
abstract: Current smokers in the general population have a lower 2 h plasma glucose after an oral glucose tolerance test (OGTT) and a higher HbA1c than non-smokers, but the relationships between OGTT/HbA1c and smoking status have not been addressed in pregnancy. We analysed glycaemic measurements in women with gestational diabetes mellitus in relation to smoking status.
  
  
  
  We performed a review of the prospectively collected database of the diabetes and pregnancy clinic. We included women with gestational diabetes mellitus and a singleton pregnancy who delivered between 1986 and 2006. Bivariate and multivariate analyses were used to evaluate patient characteristics in relation to smoking status.
  
  
  
  A total of 2361 women met the inclusion criteria: 556 (23.5%) were active smokers, 266 (11.3%) quit during pregnancy and 1539 (65.2%) were non-smokers. Most baseline characteristics were similar across groups. Diagnostic OGTT was performed at a gestational age of [median (25th, 75(th) centiles)] 29 weeks (26, 33). Women who smoked at the beginning of pregnancy had a higher 1-h plasma glucose than non-smokers [11.8 (11, 12.7), 11.6 (11, 12.6) and 11.5 (10.8, 12.5) mmol/l, for active smokers, those who quit during pregnancy and non-smokers, respectively, P < 0.001] and a lower 3-h plasma glucose [7.3 (5.9, 8.4), 7.6 (6.4, 8.7) and 8.0 (6.8, 9.0) mmol/l, respectively, P < 0.001]. HbA1c was higher in women who smoked at the beginning of pregnancy. Multiple regression analysis confirmed the independent association of smoking status with HbA1c and OGTT plasma glucose.
  
  
  
  In women with gestational diabetes mellitus who smoke at the beginning of pregnancy, the shape of the OGTT is consistent with accelerated glucose absorption, and HbA1c is higher than expected for glycaemic values.
authors.affiliation: Department of Endocrinology and Nutrition, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Aulinas
authors.affiliation: Department of Endocrinology and Nutrition, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Colom
authors.affiliation: Department of Endocrinology and Nutrition, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
authors.forename: A
authors.initials: A
authors.lastname: García Patterson
authors.affiliation: Department of Endocrinology and Nutrition, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Ubeda
authors.affiliation: Department of Endocrinology and Nutrition, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
authors.forename: M A
authors.initials: MA
authors.lastname: María
authors.affiliation: Department of Endocrinology and Nutrition, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Orellana
authors.affiliation: Department of Obstetrics and Gynecology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.|Department of Pediatrics, Obstetrics and Gynecology, Preventive Medicine and Public Health, Universitat Autònoma de Barcelona, Barcelona, Spain.
authors.forename: J M
authors.initials: JM
authors.lastname: Adelantado
authors.affiliation: Department of Endocrinology and Nutrition, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.|Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.|Center for Biomedical Network Research on Bioengineering, Biomaterials and Nanotechnology (CIBER-BBN), Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: A
authors.initials: A
authors.lastname: de Leiva
authors.affiliation: Department of Endocrinology and Nutrition, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.|Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.|Center for Biomedical Network Research on Bioengineering, Biomaterials and Nanotechnology (CIBER-BBN), Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Corcoy
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D016208:Databases, Factual; D016640:Diabetes, Gestational / Q000175:diagnosis / Q000378:metabolism*; D005260:Female; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D015999:Multivariate Analysis; D011247:Pregnancy; D012189:Retrospective Studies; D012907:Smoking / Q000378:metabolism*; D000073869:Tobacco Smoking
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human