title: Monitoring of Diabetic Retinopathy in relation to Bariatric Surgery: a Prospective Observational Study.
abstract: To investigate the need for closer perioperative monitoring of diabetic retinopathy in patients with type 2 diabetes undergoing bariatric surgery.
  
  
  
  Prospective observational clinical study of 56 patients with type 2 diabetes undergoing bariatric surgery. The patients were examined with 7-field fundus images and optical coherence tomography scans 2 weeks before and 1, 3, 6 and 12 months after bariatric surgery. Worsening was defined as a two-step change in the Wisconsin Epidemiologic Study of Diabetic Retinopathy scale or appearance or worsening of macular edema. Postoperative changes were analyzed in a mixed model.
  
  
  
  Six patients (11 %) had any worsening at any visit, and three (5 %) persisted at 1 year. Of the 24 patients with preoperative retinopathy, 4-13 % worsened and 9-22 % improved, with significant overall improvement at 6 months (p = 0.01). Only one (3%) of the 32 patients without preoperative diabetic retinopathy had a transient worsening at 6 months. No patients developed macular edema, but the whole cohort had a minor increase in center point foveal thickness that peaked 6 months postoperatively. The patients were required to have good glucose control preoperatively where HbA1c was 6.4 ± 1.9 %.
  
  
  
  Diabetic retinopathy was clinically stable after bariatric surgery, and none of the observed changes would have resulted in a changed screening interval at our center. This supports adherence to regular diabetic retinopathy screening guidelines following bariatric surgery in well-controlled patients. A clinically negligible but statistically significant foveal thickening 6 months postoperatively warrants further study.
authors.affiliation: Department of Ophthalmology, Copenhagen University Hospital Roskilde, Køgevej 7-13, 4000, Roskilde, Denmark. troels@brynskov.com.|Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark. troels@brynskov.com.
authors.forename: Troels
authors.identifier: 0000-0002-5250-4257
authors.initials: T
authors.lastname: Brynskov
authors.affiliation: Department of Ophthalmology, Copenhagen University Hospital Roskilde, Køgevej 7-13, 4000, Roskilde, Denmark.
authors.forename: Caroline Schmidt
authors.initials: CS
authors.lastname: Laugesen
authors.affiliation: Department of Internal Medicine, Copenhagen University Hospital Holbæk, Holbæk, Denmark.
authors.forename: Annette Lykke
authors.initials: AL
authors.lastname: Svenningsen
authors.affiliation: Department of Bariatric Surgery, Copenhagen University Hospital Køge, Køge, Denmark.
authors.forename: Andrea Karen
authors.initials: AK
authors.lastname: Floyd
authors.affiliation: Department of Ophthalmology, Copenhagen University Hospital Roskilde, Køgevej 7-13, 4000, Roskilde, Denmark.|Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Torben Lykke
authors.initials: TL
authors.lastname: Sørensen
mesh_terms: D000328:Adult; D050110:Bariatric Surgery; D015992:Body Mass Index; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000503:physiopathology; D003930:Diabetic Retinopathy / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D018450:Disease Progression; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D008134:Long-Term Care / Q000379:methods; D008269:Macular Edema / Q000209:etiology; D008297:Male; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D009767:Obesity, Morbid / Q000601:surgery*; D011182:Postoperative Care / Q000379:methods; D011446:Prospective Studies; D041623:Tomography, Optical Coherence; D014792:Visual Acuity
chemical_list: D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human
keywords: Bariatric surgery; Diabetes complications; Diabetic retinopathy; Early worsening; Gastric bypass surgery; Gastric sleeve gastrectomy