title: Prognostic factors for the course of beta cell function in autoimmune diabetes.
abstract: This study presents a 2-yr follow-up of 281 patients, aged 15-34 yr, diagnosed with diabetes between 1992 and 1993. At diagnosis, 224 (80%) patients were positive for at least one of the following autoantibodies: islet cell antibodies (ICAs), glutamic acid decarboxylase antibodies (GADAs), or tyrosine phosphatase antibodies (IA-2As); the remaining 57 (20%) patients were negative for all three autoantibodies. At diagnosis, C-peptide levels were lower (0. 27; 0.16-0.40 nmol/L) in autoantibody-positive patients compared with autoantibody-negative patients (0.51; 0.28-0.78 nmol/L; P: < 0. 001). After 2 yr, C-peptide levels had decreased significantly in patients with autoimmune diabetes (0.20; 0.10-0.37 nmol/L; P: = 0. 0018), but not in autoantibody-negative patients. In patients with autoimmune diabetes, a low initial level of C-peptide (odds ratio, 2. 6; 95% confidence interval, 1.7-4.0) and a high level of GADAs (odds ratio, 2.5; 95% confidence interval, 1.1-5.7) were risk factors for a C-peptide level below the reference level of 0.25 nmol/L 2 yr after diagnosis. Body mass index had a significant effect in the multivariate analysis only when initial C-peptide was not considered. Factors such as age, gender, levels of ICA or IA-2A or insulin autoantibodies (analyzed in a subset of 180 patients) had no effect on the decrease in beta-cell function. It is concluded that the absence of pancreatic islet autoantibodies at diagnosis were highly predictive for a maintained beta-cell function during the 2 yr after diagnosis, whereas high levels of GADA indicated a course of decreased beta-cell function with low levels of C-peptide. In autoimmune diabetes, an initial low level of C-peptide was a strong risk factor for a decrease in beta-cell function and conversely high C-peptide levels were protective. Other factors such as age, gender, body mass index, levels of ICA, IA-2A or IAA had no prognostic importance.
authors.affiliation: Department of Medicine, University Hospital, 221 85 Lund, Sweden. Carina.Torn@med.lu.se
authors.forename: C
authors.initials: C
authors.lastname: Törn
authors.forename: M
authors.initials: M
authors.lastname: Landin-Olsson
authors.forename: A
authors.initials: A
authors.lastname: Lernmark
authors.forename: J P
authors.initials: JP
authors.lastname: Palmer
authors.forename: H J
authors.initials: HJ
authors.lastname: Arnqvist
authors.forename: G
authors.initials: G
authors.lastname: Blohmé
authors.forename: F
authors.initials: F
authors.lastname: Lithner
authors.forename: B
authors.initials: B
authors.lastname: Littorin
authors.forename: L
authors.initials: L
authors.lastname: Nyström
authors.forename: B
authors.initials: B
authors.lastname: Scherstén
authors.forename: G
authors.initials: G
authors.lastname: Sundkvist
authors.forename: L
authors.initials: L
authors.lastname: Wibell
authors.forename: J
authors.initials: J
authors.lastname: Ostman
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001323:Autoantibodies / Q000032:analysis*; D015415:Biomarkers; D015992:Body Mass Index; D002096:C-Peptide / Q000097:blood / Q000378:metabolism; D003922:Diabetes Mellitus, Type 1 / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007515:Islets of Langerhans / Q000473:pathology*; D008297:Male; D011379:Prognosis; D012727:Sex Characteristics; D013997:Time Factors
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D002096:C-Peptide