Brain aging in type 1 diabetes may lead to cognitive complications
Middle-aged adults with childhood-onset type 1 diabetes may have a higher volume of brain white matter hyperintensities, affecting their ability to process information, according to research in Neurology.
An ongoing prospective study of adults with type 1 diabetes showed cognitive impairment was much more severe when compared against adults without the disease, and factors such as smoking and neuropathy can triple the chances of high white matter hyperintensities (WMH) burden.
“The severity of cognitive complications and cerebral small vessel disease — which can starve the brain of oxygen — is much more intense than we expected, but it can be measured in a clinical setting,” Caterina Rosano, MD, MPH, associate professor in the department of epidemiology at University of Pittsburgh’s Graduate School of Public Health, said in a press release.
Karen A. Nunley, PhD, of the department of epidemiology at University of Pittsburgh’s Graduate School of Public Health, Rosano and colleagues analyzed data from 97 middle-aged adults with type 1 diabetes participating in the Pittsburgh Epidemiology of Diabetes Complications study, a study documenting long-term complications of diabetes among patients diagnosed between 1950 and 1980, and 81 adults without the disease participating in a separate study on effects of prehypertension on cerebral structure. Researchers performed brain imaging on participants in both cohorts and rated all images using the Fazekas scale masked to case status.
Participants with type 1 diabetes were more likely to have Fazekas scores of 2 or 3, indicating more severe WMH (P < .0001), and to perform slower on cognitive tests (digit symbol substitution, number correct: 65.7 for non-diabetes group vs. 54.9 for diabetes group; pegboard, seconds: 66 vs. 88.5 for non-diabetes and diabetes groups, respectively; P < .0001 for both). Researchers also found associations between high WMH volume and cognitive test performance (digit symbol substitution, number correct: 58.3 for low volume vs. 51.4 for high volume, P < .01; pegboard, seconds: 82.4 vs. 98.2 for low and high volume, respectively, P < .05) independent of age, education or other factors.
Karen A. Nunley
WMH were associated with slower information processing; adjusting for WMH reduced the group differences in processing speed (13% for digit symbol, 11% for pegboard, both P ≤ .05).
Results did not change after controlling for glucose levels, physical activity levels and diastolic blood pressure.
“Regardless of which variables were added to the model, [type 1 diabetes] remained significantly associated with more severe WMH,” the researchers wrote.
Participants who were smokers and had cardiac autonomic and peripheral neuropathies had a much greater chance of having high WMH volume independent of age and disease duration, according to researchers.
“Impairment in these domains could impede a patient’s ability to adhere to their daily diabetes self-care, increasing their risk of developing other diabetes-related complications or increasing the severity of existing comorbidities,” Nunley told Endocrine Today.
Clinicians should consider screening middle-aged patients with type 1 diabetes for cognitive difficulties, according to researchers. Longitudinal studies also are needed to better understand WMH development, risk factors and the long-term effects on cognition.
“We need longitudinal studies incorporating repeated measures of neuroimaging with concurrent neurocognitive assessments, ideally beginning near time of diagnosis,” Nunley said. “This would help identify potentially modifiable risk factors, a necessary step for developing intervention strategies. We also need studies to determine the extent to which white matter lesions and poor cognitive performance relate to health care use and diabetes complication rates, quality of life issues and adherence to diabetes self-management in adults with childhood-onset type 1 diabetes.” – by Regina Schaffer
Disclosure: Nunley and Rosano report no relevant financial disclosures. Please see the full study for a list of all other authors’ relevant financial disclosures.