It’s Mild Cognitive Impairment. Now What?

November 23, 2011, 12:18 PM

By PAULA SPAN

How would you react to a diagnosis of mild cognitive impairment — memory problems that allow you to continue normal daily activities, but presage an increased likelihood of developing Alzheimer’s disease within a few years?

If a genetics counselor were to sit down with you and a person you’re close to, someone who might become your caregiver when and if you need one, and to explain that within five years roughly half of those given a diagnosis of mild cognitive impairment develop Alzheimer’s — would you sink into depression? Would you change your behavior to try to lower your risk? What if you were told a genetic test for your apolipoprotein E (APOE) status, associated with Alzheimer’s disease, could provide a more specific estimate of your risk?

Mild cognitive impairment is a relatively recent term, first used by a Mayo Clinic team publishing in 1999. It acquired an official diagnostic code, allowing doctors to bill insurers for reimbursement, only a few years ago.

There’s still a lot the experts don’t know. Few studies have followed subjects with M.C.I. beyond five years, for instance. Some never progress to Alzheimer’s, but we don’t know how many. We do know that a lot of people are going to confront this issue in coming years as the population ages. In a recent Mayo Clinic study, 16 percent of almost 2,000 adults ages 70 to 89 in one Minnesota county were found to have mild cognitive impairment.

“We’re trying to understand how people respond to this information,” Scott Roberts, a public health specialist at the University of Michigan, told me in an interview. The university is one of four research sites (along with Harvard University, Howard University and the University of Pennsylvania) that will each follow 45 patients and their partners for a year to measure the effects of health education and genetic testing on those who are told they have M.C.I.

There’s a lot the investigators want to know. “Do people grasp the information we’re trying to give them?” Dr. Roberts asked. Will people at risk start taking vitamin E or doing crossword puzzles, even though there’s no evidence that either will help?

“We’re interested in the psychological adjustment of both the person and the partner,” Dr. Roberts said. “What are the likely benefits and harms of providing this information?”

Benefits? Possibly. “People might want to know in terms of planning for the future,” he suggested. “And in the future, there might be medications for mild cognitive impairment, so APOE could be a marker of whether to treat.”

The researchers may also find plenty of people who don’t want to talk about, hear about or know about where mild cognitive impairment might lead. But this study, called Reveal, is enrolling only patients and caregivers who volunteer — they’re probably already inclined to want more information.

As it happens, a previous study by this research team showed no significant increase in psychological risk when adults whose parents had Alzheimer’s disease received the results of APOE genotyping, compared with a control group of those with similar family history who didn’t learn their results.

“Not to say it’s completely benign, but we didn’t see an elevation in anxiety or depression” in those who learned their test results, Dr. Roberts said. That wasn’t what lots of medical people had expected.

So who knows what other unexpected results Reveal will turn up? Millions of people — patients, families and friends, health care providers — are going to be hearing this diagnosis in coming years. It makes sense to find out.Paula Span is the author of “When the Time Comes: Families With Aging Parents Share Their Struggles and Solutions.”