Health news report two factors which may contribute to brain tissue loss.
The first factor had something to do with chronic back pain.
The second factor had something to do with obesity in women:
Writing in The Journal of Neuroscience, the researchers said that among the volunteers with back pain they had studied, the gray matter of the brain was 5 percent to 11 percent smaller than it was in other volunteers used for comparison. "The magnitude of this decrease is equivalent to the gray matter volume lost in 10 to 20 years of normal aging," they wrote.
The lead author of the study, Dr. A. Vania Apkarian, said he had done the research hoping that it would help explain earlier findings that people with chronic back pain experienced changes in brain chemistry that affected their performance on some kinds of tests of mental functioning. "Chronic pain patients, and specifically chronic back pain patients, seem to have impairment in emotional decision making," Dr. Apkarian said.
[New York Times - Health, Nov 23 2004]
This is interesting. Chronic back pain and obesity both lead to brain atrophy. Sometimes, you don't even need Alzheimer's disease to get dementia.
Swedish researchers say that women who have been obese throughout their lives are more likely to lose brain tissue in the temporal lobe compared with women of normal weight. Loss of brain tissue has been linked to cognitive decline and an increased risk for Alzheimer's disease.
The Swedish paper "is the first study to show [that] a higher body mass index (BMI) is related to brain atrophy," said lead researcher Deborah Gustafson, a psychiatrist at Sahlgrenska University Hospital in Göteborg.
The researchers found that a higher BMI was directly linked to loss of brain tissue. "BMI was related to 11 to 14 percent higher odds of temporal lobe atrophy per one unit of [increased] BMI," Gustafson said. "Women who were, on average, heavier were more likely to have temporal lobe atrophy."
[Health Central, Nov 22 2004]
Both studies didn't explain how obesity and chronic back pain may contribute to brain atrophy.
Researchers who studied the chronic back pain factor found that the decrease in the size of the brain tissue was directly linked to the length of time the patient had been in pain. More pain exposure meant more brain tissue loss. They found that every year of chronic pain results in a loss of 1.3 cubic centimeters of gray matter, the part of the brain responsible for processing memory and information.
The lead author of the chronic back pain study, Dr Apkarian, said that "one mechanistic explanation for the decreased gray matter is overuse atrophy caused by excitotoxic and inflammatory mechanisms," all brought about by the continuous sensation of excruciating pain.
Those who studied the obesity factor, however, assumed that since obesity increases the risk of diabetes and high blood pressure, these secondary factors in turn contribute to damage that might lead to brain atrophy. As to why women are the ones affected, don't worry, the reason is circumstantial: the subjects of the study involved women only.
Protect your brain. Any sign of chronic back pain and higher than normal BMIs should prompt you to seek clinical help while there's not much damage done and processes can still be reversed.