Brain volume and white matter in youth with type 2 diabetes compared to obese and normal weight, non‐diabetic peers: A pilot study

Abstract

Type 2 Diabetes Mellitus (T2DM) and obesity are linked to specific patterns of subcortical brain atrophy and decreased microstructural integrity of white matter. Fifteen adolescents (12-21-years-old, 80% Caucasian, 15% African American, mean BMI=32)-five with T2DM confirmed by oral glucose tolerance test, five matched obese adolescent controls without diabetes (OBCN), and five matched (race, sex) normal-weight controls (NWCN)-underwent Magnetic Resonance Imaging (MRI) for the collection of gray matter volume and white matter integrity. Analyses of Variance (ANOVAs) of the neuroimaging data revealed significant differences in caudate nucleus volume [F(2,12)=7.79, p<0.05] such that the normal-weight group had significantly greater volume than the obese and T2DM groups (NWCN>OBCN, p=0.020; OBCN>T2DM, p=0.042; and NWCN>T2DM; p=0.003) after controlling for participant Body Mass Index (BMI). Similarly, there was a main effect for the volume of the thalamus [F(2,12)=4.39, p<0.05] with greater volume for both the NWC and the OBC groups in comparison to the T2DM group (NWC>T2DM, p=0.020; OBC>T2DM; p=0.040). Finally, an examination of white matter integrity among the three groups illustrated a pattern of white matter integrity reduction between normal-weight participants and both obese controls and T2DM participants, with T2DM demonstrating the greatest deficit in functional anisotropy (FA) volume, but these results were not significant after further controlling for BMI. Results from the current pilot study illuminate a host of brain morphology differences between youth with T2DM, obese youth, and normal-weight controls; future research with a larger sample size is critical.

Microstructural abnormalities in white and gray matter in obese adolescents with and without type 2 diabetes

“…Consistent with our findings, in terms of WM, lower FA values have also been found in other studies involving adolescents with type 2 diabetes (Yau et al, 2010, Rofey et al, 2015) and in most (Hsu et al, 2012, Hoogenboom et al, 2014, Zhang et al, 2014), but not all (van Bloemendaal et al, 2016) studies involving adults with type 2 diabetes. Although there is some overlap regarding the regions showing FA reduction (e.g.…”

“…Yau et al (2010) found elevations in the apparent diffusion coefficient (ADC) in this group compared to weight-matched controls without diabetes, suggesting reductions in GM density. Based on manually drawn ROIs, consistent with the present study, lower GM volume has been found in the caudate and thalamus of adolescents with type 2 diabetes compared to normal weight adolescents (Bruehl et al, 2011) and GM levels of obese adolescents have been found to differ significantly with values of the control participants (Rofey et al, 2015). This study extends these findings to an evaluation of structural differences over the whole head.…”

“…A recent study comparing youth with type 2 diabetes to non-diabetic obese and healthy weight peers found that those with type 2 diabetes had reduced thalamic volume (Rofey et al, 2015). Although not statistically significant, the study also found microstructural white matter differences indexed by fractional anisotropy (FA) between the groups; those with type 2 diabetes showing the lowest FA levels (Hsu et al, 2012).…”

“…Although not statistically significant, the study also found microstructural white matter differences indexed by fractional anisotropy (FA) between the groups; those with type 2 diabetes showing the lowest FA levels (Hsu et al, 2012). However, the Rofey et al (2015) study included only five participants per group and measured changes in a limited set of brain areas.…”

Bariatric Surgery: A Potential Treatment for Type 2 Diabetes in Youth

“…Approximately 6% of adolescents with type 2 diabetes develop renal failure by age 20 years (within 5 years of diabetes diagnosis), and by age 29 years, 2.3% have developed end-stage renal disease (24). There is also emerging evidence that youth with type 2 diabetes have decreased cognitive function, brain volume, and white matter microstructural changes compared with obese control subjects (25,26). …”