(dailyRx News) Soldiers and professional football players were never presumed to have the safest jobs. But in addition to physical injuries, research suggests the two occupations also can lead to an increased risk of dementia.
Two recent studies cited the link between head injuries and the later development of dementia in older war veterans and former pro football players. The studies were recently released at the Alzheimer's Association International Conference 2011 in Paris.
Dr. Kristine Yaffe, professor of psychiatry, neurology and epidemiology at the University of California San Francisco and director of the Memory Disorders Program at the San Francisco VA Medical center, found that veterans who had experienced traumatic brain injury (TBI) were at twice the risk for developing dementia.
Dr. Yaffe and her team reviewed the medical records of more than 281,000 veterans over the age of 55 who received care from the Veterans Health Administration, and had at least one in-patient or out-patient visit between 1997 and 2000, with a follow up occurring between 2001 and 2007.
They looked for diagnoses of TBI and dementia to see if there was a clear connection. Soldiers who experienced TBI were at a 15.3 percent risk of dementia, while those without it were at a 6.8 percent risk.
Dr. Yaffe said about 1.7 million people experience TBI in the United States each year, mostly due to falls and car crashes. The finding is especially important in light of the number of soldiers who have experienced TBI during recent conflicts. TBI is referred to as the "signature wound" in Iraq and Afghanistan, accounting for 22 percent of overall casualties and 59 percent of blast-related injuries.
The increased risk following TBI is linked to the swelling of axons, which are long cell extensions forming connections among brain cells. The findings raise hope that treatment and rehabilitation following TBI could help reduce the risk of dementia.
A second study found that former NFL football players might be at an increased risk for cognitive disorders leading to dementia in later life, though the research is preliminary.
Christopher Randolph, clinical professor of neurology at Loyola University Medical Center in Chicago, compared the possibility of mild cognitive impairment in retired pro football players and those who never played sports.
In 2001 Randolph mailed a health survey to retired football players who were members of the NFL Players' Association. A follow up survey was mailed in 2008 to players over the age of 50, focusing on memory issues. More than 500 responded to the second survey, which also was mailed to the players' spouses. The average age of those who responded was 61.
More than 35 percent of those who responded had an Alzheimer's screening score that suggested possible dementia. By comparison, the Alzheimer's Association reports that 13 percent of those over the age of 65 have dementia.
After additional telephone screenings and extensive neurological tests, researchers concluded the former athletes were clearly impaired compared to counterparts who did not play sports. Randolph suggested that repetitive head trauma from years of playing football may have diminished brain reserve, and led to earlier neurodegenerative disease.
Additional research is needed to confirm the conclusion.