title: Polymorphisms of Leptin (G2548A) and Leptin Receptor (Q223R and K109R) Genes and Blood Pressure During Pregnancy and the Postpartum Period: A Cohort.
abstract: BACKGROUND
  The genetic component related to blood pressure (BP) changes during pregnancy is still not elucidated. Thus, the aim of the study was to evaluate the association between leptin and leptin receptor polymorphisms and systolic (SBP) and diastolic BP (DBP) variation during pregnancy and the postpartum period.
  
  
  METHODS
  Prospective cohort of 146 women followed at a Public Health Center in Rio de Janeiro, Brazil, during pregnancy and the postpartum. SBP and DBP (mm Hg) were measured using an automatic sphygmomanometer. DNA was extracted by phenol-chloroform protocol and leptin (G2548A) and leptin receptor genes (Q223R and K109R) polymorphisms were genotyped using real-time PCR method. Statistical analyses included longitudinal linear mixed-effect models.
  
  
  RESULTS
  Adjusted longitudinal models showed that women carrying the G-allele of leptin gene's polymorphism began pregnancy with higher BP levels compared to the AA genotype and their levels remained higher throughout pregnancy and the postpartum period (βSBP= 4.5; 95% confidence interval (CI) = 1.0-8.0; P = 0.012; βDBP= 2.9; 95% CI = 0.1-5.8; P = 0.040). There was a significant interaction between leptin gene polymorphism and body mass index (BMI), in which the effect of BMI on increasing BP was steeper in women homozygous for the A-allele, compared with those who had at least one G-allele (βG-allele#BMI= -0.8; 95% CI = -1.5 to -0.1; P = 0.022). We did not find significant associations between leptin receptor polymorphisms and BP changes.
  
  
  CONCLUSIONS
  The G-allele of leptin gene polymorphism (G2548A) was associated with increased BP levels during pregnancy and the postpartum. Furthermore, leptin polymorphism genotypes seem to modify the well-known effect of BMI on BP.
authors.affiliation: Nutritional Epidemiology Observatory, Department of Social and Applied Nutrition, Institute of Nutrition Josué de Castro, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.|Department of Social and Applied Nutrition, Graduate Program in Nutrition, Institute of Nutrition Josué de Castro, Rio de Janeiro Federal University, Rio de Janeiro, Brazil.
authors.forename: Dayana R
authors.initials: DR
authors.lastname: Farias
authors.affiliation: Nutritional Epidemiology Observatory, Department of Social and Applied Nutrition, Institute of Nutrition Josué de Castro, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.|Department of Social Nutrition, Emilia de Jesus Ferreiro Nutrition School, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil.
authors.forename: Ana B
authors.initials: AB
authors.lastname: Franco-Sena
authors.affiliation: Nutritional Epidemiology Observatory, Department of Social and Applied Nutrition, Institute of Nutrition Josué de Castro, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.|Division of Clinical Trials and Drug Development, National Institute of Cancer, Ministry of Health, Rio de Janeiro, Brazil.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Rebelo
authors.affiliation: Department of Internal Medicine, University Hospital Clementino Fraga Filho, School of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Gil F
authors.initials: GF
authors.lastname: Salles
authors.affiliation: Department of Endemic Diseases, National School of Public Health, Oswaldo Cruz Foundation, Rio de Janeiro, RJ, Brazil.
authors.forename: Cláudio J
authors.initials: CJ
authors.lastname: Struchiner
authors.affiliation: Nutritional Epidemiology Observatory, Department of Social and Applied Nutrition, Institute of Nutrition Josué de Castro, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.|Department of Social and Applied Nutrition, Graduate Program in Nutrition, Institute of Nutrition Josué de Castro, Rio de Janeiro Federal University, Rio de Janeiro, Brazil.
authors.forename: Maisa C
authors.initials: MC
authors.lastname: Martins
authors.affiliation: Nutritional Epidemiology Observatory, Department of Social and Applied Nutrition, Institute of Nutrition Josué de Castro, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; gilberto.kac@gmail.com.
authors.forename: Gilberto
authors.initials: G
authors.lastname: Kac
mesh_terms: D000328:Adult; D000483:Alleles; D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination; D015992:Body Mass Index; D001938:Brazil / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D015994:Incidence; D020738:Leptin / Q000097:blood / Q000235:genetics*; D008875:Middle Aged; D011110:Polymorphism, Genetic; D049590:Postpartum Period / Q000097:blood / Q000235:genetics*; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000097:blood / Q000453:epidemiology / Q000235:genetics*; D011446:Prospective Studies; D060888:Real-Time Polymerase Chain Reaction; D054411:Receptors, Leptin / Q000097:blood / Q000235:genetics*; D013997:Time Factors
chemical_list: D020738:Leptin; D054411:Receptors, Leptin
keywords: blood pressure; body mass index; cohort; hypertension; leptin; leptin receptor; pregnancy; single nucleotide polymorphism.