Midlife diabetes onset tied to significant cognitive decline in ensuing 20 years

by Bruce Sylvester: Onset of diabetes raises the risk of significant memory and cognitive problems during the following 20 years researchers reported in the Dec. 2 issue of the journal Annals of Internal Medicine.

The investigators reported that diabetes appears to age the mind about five years faster than normal aging. As background, they noted that memory impairment, declining word recall and executive function strongly correlate to progression to dementia.

“The lesson is that to have a healthy brain when you’re 70, you need to eat right and exercise when you’re 50,” said lead investigator Elizabeth Selvin, PhD, MPH, associate professor of epidemiology at the Johns Hopkins University Bloomberg School of Public Health in Baltimore, Maryland. “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.”

Selvin and her team evaluated retrospectively data data from the Atherosclerosis Risk in Communities Study (ARIC), launched 1987 to follow 15,792 middle-aged adults in communities in Maryland, North Carolina, Minnesota and Mississippi.

Subjects were evaluated  at four visits approximately three years apart beginning between 1987 and 1989.They had a fifth evaluation between 2011 and 2013.

They underwent cognitive function evaluation at visits two (1990-1992), four (1996-1998) and at visit five (2011-2013).

The researchers compared cognitive decline among the subjects. They found a 19 percent greater decline than they had expected among subjects with poorly controlled diabetes, and smaller declines for those with controlled diabetes and pre-diabetes.

“If we can do a better job at preventing diabetes and controlling diabetes, we can prevent the progression to dementia for many people,” 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.”

Co-author A. Richey Sharrett, MD, DrPH, an adjunct professor at the Johns Hopkins Bloomberg School of Public Health, said, “There are many ways we can reduce the impact of cerebral blood vessel disease — by prevention or control of diabetes and hypertension, reduction in smoking, increase in exercise and improvements in diet. 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.”