Early Cognitive Deficits in Type 2 Diabetes: A Population-Based Study.
Evidence links type 2 diabetes to dementia risk. However, our knowledge on the initial cognitive deficits in diabetic individuals and the factors that might promote such deficits is still limited. This study aimed to identify the cognitive domains initially impaired by diabetes and the factors that play a role in this first stage. Within the population-based Swedish National Study on Aging and Care-Kungsholmen, 2305 cognitively intact participants aged ≥60 y were identified. Attention/working memory, perceptual speed, category fluency, letter fluency, semantic memory, and episodic memory were assessed. Diabetes (controlled and uncontrolled) and prediabetes were ascertained by clinicians, who also collected information on vascular disorders (hypertension, heart diseases, and stroke) and vascular risk factors (VRFs, including smoking and overweight/obesity). Data were analyzed with linear regression models. Overall, 196 participants (8.5%) had diabetes, of which 144 (73.5%) had elevated glycaemia (uncontrolled diabetes); 571 (24.8%) persons had prediabetes. In addition, diabetes, mainly uncontrolled, was related to lower performance in perceptual speed (β - 1.10 [95% CI - 1.98, - 0.23]), category fluency (β - 1.27 [95% CI - 2.52, - 0.03]), and digit span forward (β - 0.35 [95% CI - 0.54, - 0.17]). Critically, these associations were present only among APOEɛ4 non-carriers. The associations of diabetes with perceptual speed and category fluency were present only among participants with VRFs or vascular disorders. Diabetes, especially uncontrolled diabetes, is associated with poorer performance in perceptual speed, category fluency, and attention/primary memory. VRFs, vascular disorders, and APOE status play a role in these associations.
Aging Research Center, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet and Stockholm University, Stockholm, Sweden.
Anna
A
Marseglia
Aging Research Center, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet and Stockholm University, Stockholm, Sweden.|Stockholm Gerontology Research Center, Stockholm, Sweden.
Laura
L
Fratiglioni
Aging Research Center, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet and Stockholm University, Stockholm, Sweden.
Erika J
EJ
Laukka
Aging Research Center, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet and Stockholm University, Stockholm, Sweden.
Giola
G
Santoni
Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
Nancy L
NL
Pedersen
Aging Research Center, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet and Stockholm University, Stockholm, Sweden.
Lars
L
Bäckman
Aging Research Center, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet and Stockholm University, Stockholm, Sweden.|Department of Epidemiology and Biostatistics, School of Public Health, Tianjin Medical University, China.
Weili
W
Xu
D000368:Aged; D000369:Aged, 80 and over; D001057:Apolipoproteins E / Q000235:genetics; D003072:Cognition Disorders / Q000209:etiology*; D018672:Community Health Planning; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000235:genetics; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016015:Logistic Models; D008297:Male; D008609:Mental Status Schedule; D008875:Middle Aged; D009483:Neuropsychological Tests
D001057:Apolipoproteins E
Apolipoprotein E4; cognition; type 2 diabetes mellitus; vascular disorders