Some people become calmer and less troubled by life's frustrations as they age.
Or, are they just becoming apathetic because their brains are shrinking?
The brain tends to shrink with age — about 1.9 percent every 10 years — but people who display signs of apathy, such as loss of energy, slowness of thought and movement, and lack of emotion, show greater-than-average brain atrophy for their age, according to a recent study in the journal Neurology.
Brain imaging of 4,354 older dementia-free people showed that those with two or more symptoms of apathy had 1.4 percent less gray matter, which consists of brain cells, and 1.6 percent less white matter, which consists of the wirelike connections between cells. That's the equivalent of two or three years of normal aging in an older person, according to lead author Lenore J. Launer, a researcher with the National Institute on Aging.
"Just as signs of memory loss may signal brain changes related to brain disease, apathy may indicate underlying changes," Launer found. "The fact that participants in our study had apathy without depression should turn our attention to how apathy alone could indicate brain disease."
Does apathy promote brain shrinkage, or does brain shrinkage promote apathy? The researchers don't know, but they point out that brain shrinkage is often found in people with Alzheimer's disease, suggesting that it could be a sign of brain deterioration.
Apathy also occurs in older people suffering from depression; this could complicate treatment because selective serotonin reuptake inhibitors, which boost levels of serotonin in the brain and often relieve depression, could aggravate symptoms of apathy. Yet about 10 to 15 percent of the people in the Neurology study were taking antidepressants even though they showed no symptoms of depression, according to the authors.
So what can be done? Although brain shrinkage with age cannot be avoided, it can be minimized if you avoid smoking, keep your weight and blood pressure under control, and aren't diabetic, according to researchers at the University of California, Davis who also published their results in Neurology.
According to the authors:
• People with high blood pressure show a faster rate of damage to blood vessels in the brain.
• People with diabetes or elevated blood sugar show faster shrinkage of the brain, especially in the hippocampus, the area needed to encode new memories.
• Smokers tend to lose brain volume faster than nonsmokers.
• People who are obese in middle age tend to show more rapid brain decline.
"We can't cure aging, but the idea of a healthy body, healthy mind is very real," lead author Charles DeCarli said.
Tom Valeo writes on health matters. Email him at tom.val[email protected]