Diabetes: Insulin Resistance May Link Brain Disconnections and Cognitive Dysfunction

MedicalResearch.com Interview with:
Gao-Jun Teng, MD
Chair and Professor, Dept of Radiology
Zhongda Hospital, Southeast University
Nanjing 210009, China

MedicalResearch.com: What are the main findings of the study?

Answer: This current study demonstrates that the aberrant resting-state functional connectivity among default mode network (DMN) regions, especially the posterior cingulated cortex (PCC) to right middle temporal gyrus (MTG), is associated with insulin resistance and cognitive performance, which might be the key to understanding the cognitive impairment in type 2 diabetes (T2DM).

MedicalResearch.com: Were any of the findings unexpected?

Answer: The results of this study were not unexpected. Based on the aforementioned findings, we expected that T2DM might cause abnormal functional connectivity within the DMN, especially in the MTG region. Furthermore, we attempted to investigate the correlation of the alterations in functional connectivity with insulin resistance and neuropsychological performance. This investigation might contribute to a better understanding of the relationships between the insulin dysfunction and the selected brain regions in type 2 diabetes.

MedicalResearch.com:  What should clinicians and patients take away from your report?

Answer: These findings have important clinical implications. Patients with type 2 diabetes develop aberrant functional connectivity of the PCC, which is associated with insulin resistance in selected brain regions, especially the MTG. Additionally; disturbance in resting-state functional connectivity within the DMN regions revealed by functional magnetic resonance imaging (fMRI) may play a pivotal role in evaluating the cognitive dysfunction of type 2 diabetes.

MedicalResearch.com:  What recommendations do you have for future research as a result of this study?


First, we recommend that further longitudinal studies using fMRI experiments would be beneficial to establish the cause-effect relationships between the brain disconnections, insulin resistance and cognitive dysfunction.

Second, HOMA-IR may not be a good index for assessing insulin resistance. More sophisticated measurements, such as hyperinsulinemic-euglycemic clamp and intravenous glucose tolerance test, may provide more accurate assessment. Finally, other potential confounding factors, such as macro or micro-vascular disease and ApoEε4, should be completely examined for additional covariates in future study.

Aberrant Brain Functional Connectivity Related to Insulin Resistance in Type 2 Diabetes: A Resting-State fMRI Study

Chen YC1, Jiao Y, Cui Y, Shang SA, Ding J, Feng Y, Song W, Ju SH, Teng GJ.

Last Updated on March 31, 2014 by Marie Benz MD FAAD