Cognitive decline may start earlier than previously thought — about age 45, according to a study released this week — but that doesn't mean those hitting middle age should think their brain functions are doomed.
"I think the notion that we do things as well when we're older as when we're younger is not that tenable," said Dr. Marc L. Gordon, chief of neurology at Zucker Hillside Hospital and an Alzheimer's disease researcher at the Feinstein Institute for Medical Research, both in New York. "We don't expect a 45-year-old to play baseball as well as a 25-year-old. I think it's been fairly well documented that a lot of abilities, including our ability to remember things, declines over time."
The British Medical Journal study focused on a series of specialized, sensitive cognitive tests given to 7,390 men and women ages 45 to 70. Researchers noticed declines over 10 years in areas such as memory and reasoning but not in vocabulary. Over the decade there was a 3.6% decline in mental reasoning in men ages 45 to 49, and a 9.6% drop in men ages 65 to 70. In women, the declines were 3.6% for those ages 45 to 49 and 7.4% decline for those ages 65 to 70. Researchers controlled for various education levels among the participants.
"I certainly think this is important to put in perspective and not be duly alarmist," Gordon added. "We should recognize that [cognitive decline] is part of the normal aging process."
But we should also be looking at the bigger picture, Gordon said: "We should be thinking about what if anything we can do now to modify our risk for increased cognitive decline. ... If we're going to try to intervene to do primary prevention of cognitive impairment later in life, this is the time frame we should be targeting."
There's also a message for those in the medical community, said neurosurgeon Ty Thaiyananthan, co-medical director of the Chapman Neurosurgical and Spine Institute in Orange. "The message is to be a little more vigilant with a younger population. They shouldn't just be looking for [signs of cognitive decline] in older patients."
Those in middle age shouldn't be overly concerned if they occasionally forget where they placed their keys. More worrisome is forgetting how to prepare a meal: "Those are the types of cognitive deficits that we associate with Alzheimer's disease, things that impair activities of daily life," Thaiyananthan said.