TUESDAY, Jan. 2, 2007 (HealthDay News) -- A simple blood test to measure uric acid levels may help predict cognitive problems associated with old age, according to researchers from Johns Hopkins and Yale University medical schools.
For the study, which appears in the January issue of Neuropsychology, researchers performed a blood test to measure the uric acid levels of 96 community-dwelling adults aged 60 to 92 years old.
Information processing and memory were measured by the Wechsler Adult Intelligence Scale and other well-established neuropsychological tests.
The participants with uric acid levels in the high-normal range, defined as 5.8 to 7.6 milligrams per deciliter (mg/dL) in men and 4.8 to 7.1 mg/dL in women, had the lowest scores on tests of mental processing speed, verbal memory and working memory, regardless of age, sex, weight, race, education, diabetes, hypertension, smoking and alcohol abuse.
The findings suggest that uric acid testing may be a useful marker for the risk of cognitive impairment.
"It might be useful for primary-care physicians to ask elderly adults with high normal serum uric acid about problems they might be having with their thinking, and perhaps refer those who express concern, or whose family members express concern, for neuropsychological screening," study author David Schretlen said in a prepared statement.
The authors said that further studies are needed to determine whether drugs that reduce uric acid, such as allopurinol, could help older people with high-normal uric acid avoid the cognitive decline that often precedes dementia.
Schretlen said that for reasons that are not entirely clear, uric acid levels increase with age. And higher levels have been linked with high blood pressure, atherosclerosis, type 2 diabetes and the "metabolic syndrome" of abdominal obesity and insulin resistance -- all known risk factors for dementia.
Furthermore, according to Schretlen, there is mounting evidence that end-stage kidney disease increases the risk of cognitive dysfunction and dementia in older people.
It is odd that uric acid is linked with cognitive decline, since it has antioxidant properties that are thought to be protective in other situations. Even so, evidence of the connection between uric acid and cognitive function indicates that uric acid testing could be a valuable tool for detecting early cognitive problems in old age, according to the study.
More information
The American Academy of Family Physicians has more about dementia.
