Without Proper Control, Diabetes May Lead to Mental Decline

Diabetes patients diagnosed in middle age faced raised cognitive decline risk later

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) In middle age, taking care of yourself now could mean avoiding a health crisis later — and that may go double for diabetes patients. Middle-aged diabetes patients may have a raised risk for mental decline later in life.

Patients diagnosed with diabetes during midlife were more likely than those without diabetes to experience cognitive health decline within 20 years, a new study found. The authors of this study found that the brains of diabetes patients aged faster than the brains of patients without diabetes.

These researchers said the study findings should motivate diabetes patients to make good health choices to control their diabetes and possibly prevent mental decline.

"Knowing that the risk for cognitive impairments begins with diabetes and other risk factors in mid-life can be a strong motivator for patients and their doctors to adopt and maintain long-term healthy practices” stated study author A. Richey Sharrett, MD, in a press release.

Elizabeth Selvin, PhD, associate professor of epidemiology at the Johns Hopkins Bloomberg School of Public Health in Baltimore, MD, led this study.

Dr. Selvin and team used data from the Atherosclerosis Risk in Communities (ARIC) study. The ARIC study measured mental and thinking abilities in 15,792 adults from 1987 to 2013. Patients' ages ranged between 48 and 67. Of these patients, 13.3 percent had diabetes.

A doctor assessed the patients' physical health five times throughout the study. At visits two, four and five, a doctor also assessed the patients' mental health.

Dr. Selvin and team examined the results of the patients' glycated hemoglobin (HbA1c) blood tests. HbA1c tests measure blood sugar levels. A patient with an HbA1c of 6.5 percent or higher was diagnosed with diabetes. Past studies have tied high blood sugar to mental decline, these researchers noted.

Patients with type 1 diabetes can’t produce insulin. Type 2 diabetes patients can't process insulin correctly. Insulin is a hormone that regulates blood sugar. Dr. Selvin and colleagues studied patients with both types.

Diabetes is marked by raised glucose (sugar) levels in the blood. Untreated diabetes can lead to blindness, nerve damage and kidney disease. Patients can control the condition with medication, exercise and healthy diet changes.

“If we can do a better job at preventing diabetes and controlling diabetes, we can prevent the progression to dementia for many people," Dr. Selvin said. "Even delaying dementia by a few years could have a huge impact on the population, from quality of life to health care costs."

Dementia is a loss of brain function that affects memory, language and behavior. The most common form of dementia is Alzheimer's disease.

Researchers found that midlife diabetes patients had a 19 percent greater mental decline over 20 years than patients without diabetes.

Mental decline was greater among prediabetes patients than in patients without prediabetes. Prediabetes is a condition in which blood sugar levels are higher than normal — but not high enough to be considered diabetes. Prediabetes patients had an HbA1c between 5.7 and 6.4 percent.

"The lesson is that to have a healthy brain when you're 70, you need to eat right and exercise when you're 50," Dr. Selvin said. "There is a substantial cognitive decline associated with diabetes, pre-diabetes and poor glucose control in people with diabetes. And we know how to prevent or delay the diabetes associated with this decline."

These researchers emphasized the importance of using weight control, exercise, and a healthy diet to prevent and control diabetes.

This study was published online Dec. 1 in Annals of Internal Medicine.

The National Institutes of Health (NIH) funded the research. Study authors Drs. Michael Griswold and B. Gwen Windham received personal funding from the NIH.

Review Date: 
November 29, 2014
Last Updated:
December 3, 2014