Research Looks at the Brain; Diabetes

Rewiring the Brain to Manage Pain

Two distinct mental strategies used to manage pain—focusing attention externally and re-appraising the pain—involve different brain pathways, according to new research using functional magnetic resonance imaging (fMRI). The study appeared in the journal Anesthesiology (2011, 115 [4], 844–51).

Investigators from Stanford University in Palo Alto, California, wanted to determine whether distinct methods of pain management impacted the same neural pathways. The researchers tested subjects with chronic pain under two separate conditions. For the first analysis, subjects used “external focus of attention” to manage pain by drawing their attention away from their pain and focusing on something else. MRI data showed activity in cortical areas, which are responsible for higher brain functions. In the second condition, study subjects were told to use “re-appraisal”—changing the interpretation of pain from threatening to nonthreatening. For example, a subject re-appraises a situation when he reassures himself that his pain is bearable and he won’t let it stop him from functioning. MRI data for this mental strategy showed activity in deep brain structures, which are related to emotional behavior, and in some cortical regions.

Senior study author Sean C. Mackey, MD, PhD, chief of the division of pain management at Stanford University, said, “Our study helped support that each cognitive strategy may have a unique brain pattern distinct from other strategies.”

Mackey and colleagues believed that their finding might explain why some strategies are more effective for certain patients than others. Limitations of the study were that subjects did not necessarily represent all individuals who suffer from chronic pain and that the sample size was small. More research was recommended.

Unmanaged Diabetes Increases Dementia Risk

Scientific findings suggest that people with diabetes have a significantly higher risk of developing dementia. Fitness and wellness professionals therefore have good reason to emphasize the importance of healthy lifestyle changes, including regular physical activity, in the role of diabetes management.

A longitudinal prospective cohort study featured over 90% of the older adults in Hisayama, Japan, a suburb of Fukuoka. Researchers enrolled 1,017 Japanese men and women, aged 60 and older, who did not have dementia. The purpose was to evaluate the association between blood glucose levels and the occurrence of dementia over time. Subjects completed a baseline test for oral glucose tolerance levels; investigators then followed the subjects for 15 years and tested for dementia. Two hundred and thirty-two people had developed the disease.

Data analysis showed that people with diabetes were twice as likely to exhibit dementia as those with normal blood sugar levels. In addition, people with impaired glucose tolerance, which had not yet progressed into diabetes, also had a higher risk of cognitive impairment than those with normal blood sugar values. To arrive at this conclusion, investigators adjusted for other factors such as age, gender, high blood pressure or high cholesterol to focus on the connection between blood sugar levels and the incidence of any type of dementia, including Alzheimer’s disease and vascular dementia.

“Our findings emphasize the need to consider diabetes as a potential risk factor for dementia,” said study author Yutaka Kiyohara, MD, PhD, of Kyushu University in Fukuoka, Japan. “This study also showed that the risk of developing dementia significantly increased with rising blood sugar level at 2 hours after ingestion of 75-g [grams] glucose, which corresponds to blood sugar levels in a post-meal state. This is a new finding in terms of studies on this issue.” More research was recommended.

The study appeared in the American Academy of Neurology’s journal, Neurology (2011; 77, 1126–34).