Diabetes & cognitive impairment

A review and a large study have recently added to the growing evidence that type 2 diabetes is not only a risk factor for Alzheimer's, but is also linked to poorer cognitive function and faster age-related cognitive decline. The amount of this also seems to be related to glucose control in a dose-dependent manner.

Somewhat surprisingly, there is evidence that the association is not linked to vascular factors, but is in significant part explained by neuron loss. That part is not surprising — brains 'naturally' shrink with age, and growing evidence points to the importance of exercise (which promotes the growth of new neurons) in combating that loss. If diabetics are less likely to exercise (which seems likely, given the strong association with obesity), this may, at least in part, account for the greater brain atrophy.

Type 2 diabetes linked to poorer executive function

A meta-analysis of 60 studies involving a total of 9815 people with Type 2 diabetes and 69,254 control individuals, has found a small but reliable association between diabetes and poorer executive function. This was true across all aspects of executive function tested: verbal fluency, mental flexibility, inhibition, working memory, and attention.

Unfortunately, effective diabetes management does depend quite heavily on executive function, making this something of a negative feedback cycle.

http://www.eurekalert.org/pub_releases/2015-02/uow-t2d021315.php

Diabetes in midlife linked to greater age-related cognitive decline

A long-running U.S. study involving 13,351 adults, has found that cognitive decline over 19 years was 19% greater among those who had diabetes in midlife. Moreover, cognitive decline increased with higher hemoglobin A1c level and longer duration of diabetes.

At the beginning of the study, participants were aged 48-67 (median: 57), and 13% of participants were diagnosed as diabetic. Cognition was tested using delayed word recall, digit symbol substitution, and word fluency tests.

The findings support the view that glucose control in midlife is important to protect against cognitive decline later in life.

http://www.jwatch.org/na36497/2014/12/31/diabetes-midlife-associated-with-accelerated-cognitive

http://www.sciencedaily.com/releases/2014/12/141201191253.htm

http://www.psychiatryadvisor.com/diabetes-may-accelerate-cognitive-decline/article/386208/

Brain atrophy linked with cognitive decline in diabetes

A 2013 study showed that almost half of the cognitive impairment seen among diabetics was explained by their loss of gray matter.

Brain scans and cognitive tests of 350 people with Type 2 diabetes and 363 people without diabetes revealed that those with diabetes had more cerebral infarcts and greater shrinkage in specific regions of the brain. Diabetes was associated with poorer visuospatial memory, planning, visual memory, and processing speed. These associations were independent of vascular risk factors, cerebrovascular lesions, or white matter volume, but almost half of the associations were explained by the shrinkage of gray matter in the hippocampus and across the brain.

http://www.eurekalert.org/pub_releases/2013-09/mu-bal091113.php

Reference: 

Vincent, C. & Hall, P.A. 2015. Executive Function in Adults With Type 2 Diabetes: A Meta-Analytic Review. Psychosomatic Medicine, doi: 10.1097/PSY.0000000000000103

[3910] Rawlings, A. M., A. Sharrett R., Schneider A. L. C., Coresh J., Albert M., Couper D., et al.
(2014).  Diabetes in midlife and cognitive change over 20 years: a cohort study.
Annals of Internal Medicine. 161(11), 785 - 793.

[3909] Moran, C., Phan T. G., Chen J., Blizzard L., Beare R., Venn A., et al.
(2013).  Brain Atrophy in Type 2 Diabetes Regional distribution and influence on cognition.
Diabetes Care. 36(12), 4036 - 4042.

Related News

A mouse study has found that obese mice had high levels of interleukin 1 in both their blood and their brains, and this was associated with:

As many of you will know, I like nature-improves-mind stories.

Data from the very large, long-running UK National Child Development Study has revealed that those who exercised at least four times weekly as both a child and an adult performed better on cognitive tests at age 50 than those who exercised two to three times per month or less, and the latter

Previous research has pointed to an association between not having teeth and a higher risk of cognitive decline and dementia. One reason might have to do with inflammation — inflammation is a well-established risk factor, and at least one study has linked gum disease to a higher dementia risk.

A study using data from the Lothian Birth Cohort (people born in Scotland in 1936) has analyzed brain scans of 638 participants when they were 73 years old.

I’ve reported before on the growing evidence that metabolic syndrome in middle and old age is linked to greater risk of cognitive impairment in old age and faster decline.

The study involved 120 healthy older adults (60-79) from Shanghai, who were randomly assigned to one of four groups: one that participated in three sessions of tai chi every week for 40 weeks; another that instead had ‘social interaction’ sessions (‘lively discussions’); another in which partici

A study designed to compare the relative benefits of exercise and diet control on Alzheimer’s pathology and cognitive performance has revealed that while both are beneficial, exercise is of greater benefit in reducing Alzheimer’s pathology and cognitive impairment.

More findings from the long-running Mayo Clinic Study of Aging reveal that using a computer plus taking moderate exercise reduces your risk of mild cognitive impairment significantly more than you would expect from simply adding together these two beneficial activities.

I’ve talked before about Dr Berman’s research into Attention Restoration Theory, which proposes that people concentrate better after nature walks or even just looking at nature scenes.

Pages

Subscribe to Latest newsSubscribe to Latest newsSubscribe to Latest health newsSubscribe to Latest news