title: Fatigue and cognitive symptoms in patients with diabetes: relationship with disease phenotype and insulin treatment.
abstract: Neurobehavioral symptoms are frequently reported in patients with diabetes. Nevertheless, the characterization of the specific symptom dimensions that develop in diabetic patients with respect to disease phenotype and treatment status remains obscure. This study comparatively assessed fatigue symptoms and cognitive performance using a dimensional approach in 21 patients with insulin-treated type 1 diabetes, 24 type 2 diabetic patients either insulin-free or undergoing insulin treatment for at least six months, and 15 healthy subjects. Specific dimensions of fatigue were assessed using the Multidimensional-Fatigue-Inventory (MFI). Cognitive performance on tests of choice reaction time, pattern recognition memory and spatial planning was evaluated using the Cambridge-Neuropsychological-Automated-Battery (CANTAB). Body mass index (BMI) and glycated-hemoglobin (HbA1C) concentrations were collected, as well as information on diabetes complications and disease duration. Patients with type 2 diabetes, regardless of insulin treatment status, exhibited higher scores of fatigue, primarily in the dimensions of general and physical fatigue as well as reduced activity. Cognitive alterations, in the form of longer reaction times and impaired spatial planning, were also detected in type 2 diabetic patients treated with insulin. These alterations were overall unrelated to glucose control, as reflected in HbA1C levels, and were not explained by complications and duration of diabetes. No specific alteration was measured in type 1 diabetic patients who exhibited fatigue scores and cognitive performance comparable to healthy participants. While associated with fatigue, increased BMI did not significantly account for the relationship of type 2 diabetes with general fatigue and physical fatigue. BMI, however, modulated the association of type 2 diabetes with reduced activity and the association of insulin-treated type 2 diabetes with psychomotor slowing. These findings reveal specific fatigue and cognitive symptoms in patients with type 2 diabetes and suggest the involvement of differential pathophysiological processes.
authors.affiliation: INRA, Nutrition and Integrative Neurobiology-NutriNeuro, UMR 1286, F-33076 Bordeaux, France.
authors.forename: Julie
authors.initials: J
authors.lastname: Lasselin
authors.forename: Sophie
authors.initials: S
authors.lastname: Layé
authors.forename: Jean-Baptiste
authors.initials: JB
authors.lastname: Barreau
authors.forename: Alice
authors.initials: A
authors.lastname: Rivet
authors.forename: Marie-Josée
authors.initials: MJ
authors.lastname: Dulucq
authors.forename: Henri
authors.initials: H
authors.lastname: Gin
authors.forename: Lucile
authors.initials: L
authors.lastname: Capuron
mesh_terms: D000328:Adult; D000368:Aged; D001786:Blood Glucose; D002755:Choice Behavior; D003072:Cognition Disorders / Q000150:complications / Q000175:diagnosis*; D003922:Diabetes Mellitus, Type 1 / Q000150:complications / Q000188:drug therapy / Q000523:psychology*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000188:drug therapy / Q000523:psychology*; D005221:Fatigue / Q000150:complications / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D007328:Insulin / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011930:Reaction Time
chemical_list: D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin