title: Pregnancy-induced increase in circulating IGF-I is associated with progression of diabetic retinopathy in women with type 1 diabetes.
abstract: OBJECTIVE
  To evaluate the influence of Insulin-like Growth factor-I (IGF-I) and Placental Growth Hormone (GH) on progression of diabetic retinopathy during pregnancy in women with type 1 diabetes.
  
  
  METHODS
  Observational study of 88 consecutive pregnant women with type 1 diabetes for median 16.5 years (range 1-36) and HbA(1c) 6.6% (5.2-10.5) in early pregnancy. At 8, 14, 21, 27 and 33 weeks blood samples were drawn for measurement of IGF-I, placental GH and Hemoglobin A(1c) (HbA(1c)) and blood pressure was recorded. Fundus photography was performed at 8 and 27 weeks. Diabetic retinopathy was classified in five stages. Progression was defined as deterioration of at least one stage of diabetic retinopathy and/or development of macular edema on at least one eye.
  
  
  RESULTS
  Placental GH and IGF-I levels increased throughout pregnancy and new onset or progression of diabetic retinopathy occurred in 22 (25%). A steeper increase in women with progression of diabetic retinopathy resulted in higher IGF-I levels at 27 weeks (p=0.01) and 16% higher IGF-I levels throughout pregnancy (p=0.02) compared with women without progression while similar levels of placental GH (p=0.58) and HbA(1c) (p=0.85) were observed throughout pregnancy. In a multivariate logistic regression analysis, progression of diabetic retinopathy was associated with higher IGF-I levels at 33 weeks (odds ratio 2.0 [95% confidence interval 1.1-3.6], p=0.02) and higher systolic blood pressure at 8 weeks (1.9 [1.1-3.2], p=0.02) independent of placental GH and HbA(1c) levels.
  
  
  CONCLUSIONS
  Pregnancy-induced increase in IGF-I levels is associated with progression of diabetic retinopathy in women with type 1 diabetes.
authors.affiliation: Center for Pregnant Women with Diabetes, Rigshospitalet, Denmark. enel@dadlnet.dk
authors.forename: Lene
authors.initials: L
authors.lastname: Ringholm
authors.forename: Marianne
authors.initials: M
authors.lastname: Vestgaard
authors.forename: Caroline S
authors.initials: CS
authors.lastname: Laugesen
authors.forename: Anders
authors.initials: A
authors.lastname: Juul
authors.forename: Peter
authors.initials: P
authors.lastname: Damm
authors.forename: Elisabeth R
authors.initials: ER
authors.lastname: Mathiesen
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000150:complications* / Q000175:diagnosis; D003930:Diabetic Retinopathy / Q000097:blood* / Q000175:diagnosis; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005865:Gestational Age; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis / Q000378:metabolism*; D011247:Pregnancy; D011254:Pregnancy in Diabetics / Q000097:blood* / Q000473:pathology; D011379:Prognosis; D015854:Up-Regulation; D055815:Young Adult
chemical_list: D015415:Biomarkers; D007334:Insulin-Like Growth Factor I