title: Impaired Awareness of Hypoglycemia in Adults With Type 1 Diabetes Is Not Associated With Autonomic Dysfunction or Peripheral Neuropathy.
abstract: OBJECTIVE
  Impaired awareness of hypoglycemia (IAH) is a risk factor for severe hypoglycemia in people with insulin-treated diabetes; autonomic neuropathy has been suggested to underlie its development. The aim was to evaluate a putative association between IAH and autonomic dysfunction using novel and sensitive measures of autonomic neural function.
  
  
  METHODS
  Sixty-six adults with type 1 diabetes were studied, 33 with IAH and 33 with normal awareness of hypoglycemia (NAH), confirmed by formal testing. Participants were matched for age, sex, and diabetes duration. Clinical and laboratory evaluations included extensive autonomic function testing, peripheral nerve conduction studies, and quantitative sensory testing. Composite abnormality Z scores were used for group comparisons.
  
  
  RESULTS
  The IAH and NAH group had similar median (interquartile range) age of 48 (14.5) vs. 47 (14.5) years, diabetes duration of 30 (13.5) vs. 31 (13.5) years, and mean ± SD HbA1c 7.8 ± 2.2% vs. 8.1 ± 1.9%, respectively. The autonomic composite Z score did not differ between the two groups (mean difference -0.15, 95% CI -0.46, 0.16; P = 0.33), nor did the thermal detection (mean difference 0.15, 95% CI -0.31, 0.61; P = 0.51) or nerve conduction scores (mean difference 0.03, 95% CI -0.43, 0.49; P = 0.89).
  
  
  CONCLUSIONS
  In adults with type 1 diabetes, IAH was not associated with autonomic dysfunction or peripheral neuropathy.
authors.affiliation: Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Sandra E
authors.initials: SE
authors.lastname: Olsen
authors.affiliation: Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway Department of Endocrinology, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway.
authors.forename: Marit R
authors.initials: MR
authors.lastname: Bjørgaas
authors.affiliation: Department of Endocrinology, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway Department of Public Health and General Practice, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Bjørn O
authors.initials: BO
authors.lastname: Åsvold
authors.affiliation: Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway Section of Clinical Neurophysiology, Department of Neurology, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway.
authors.forename: Trond
authors.initials: T
authors.lastname: Sand
authors.affiliation: Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway Section of Clinical Neurophysiology, Department of Neurology, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway.
authors.forename: Marit
authors.initials: M
authors.lastname: Stjern
authors.affiliation: British Heart Foundation Centre for Cardiovascular Science, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, U.K.
authors.forename: Brian M
authors.initials: BM
authors.lastname: Frier
authors.affiliation: Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway Department of Work Psychology and Physiology, National Institute of Occupational Health, Oslo, Norway Section for Clinical Neurophysiology, Department of Neurology, Oslo University Hospital, Ullevål, Norway kristian.b.nilsen@ntnu.no.
authors.forename: Kristian B
authors.initials: KB
authors.lastname: Nilsen
mesh_terms: D000328:Adult; D001342:Autonomic Nervous System Diseases / Q000503:physiopathology* / Q000523:psychology; D001364:Awareness; D003430:Cross-Sectional Studies; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology* / Q000523:psychology; D003929:Diabetic Neuropathies / Q000503:physiopathology* / Q000523:psychology; D005260:Female; D006801:Humans; D007003:Hypoglycemia / Q000503:physiopathology* / Q000523:psychology*; D008297:Male; D008875:Middle Aged; D010523:Peripheral Nervous System Diseases / Q000503:physiopathology* / Q000523:psychology; D012307:Risk Factors