Using data from the Department of Veterans Affairs National Patient Care Database, scientists from the University of California-San Francisco analyzed files of 181,093 veterans ages 55 and older without dementia from 1997 to 2000. The mean age at the start of the study was 68, and 97% were male.
During the follow-up period from 2001 to 2007, the researchers learned that 53,155 veterans were diagnosed with dementia or cognitive impairment. Veterans who had post-traumatic stress developed dementia at a rate of 10.6% over seven years, while those who didn't have the disorder had a rate of 6.6%, the researchers reported.
The researchers reported their findings at the International Conference on Alzheimer's Disease in Vienna.
"The results are not surprising," says Robert Wilson, neuropsychologist in the Alzheimer's Disease Center at Rush University Medical Center. "Our thinking is that things like PTSD or chronic anxiety or depression don't cause dementia themselves but may make us more vulnerable to it."
Other research presented Sunday and today at the Alzheimer's conference:
•Two separate studies evaluate the influence of DHA, an omega 3 fatty acid, supplements on brain health. The first study, which was government-funded, looks at DHA supplementation in patients with mild to moderate Alzheimer's and finds that the supplements offered no cognitive benefits to patients. The other, sponsored by a DHA maker, Martek Biosciences Corp., suggests supplements may help in healthy older adults who have mild memory loss.
•Wake Forest University School of Medicine scientists find that moderate alcohol intake (one to two drinks a day) is linked to a 37% lower risk of dementia in patients with normal cognition at baseline, not those who already have cognitive impairment.
•University of Connecticut scientists report that in an online study of 676 adults, many don't know the risk factors for dementia: 61% incorrectly believe there is no link between dementia and the cardiovascular risk factors obesity and high blood pressure; 66% do not know high stress is a risk factor; and 38% are unaware exercise protects against dementia.
•The number of people who have Alzheimer's disease and dementia is increasing among the "oldest old," those over 80, Italian researchers report. The finding contradicts observational studies that suggested the number of people with dementia levels off and perhaps drops late in life.http://www.usatoday.com/news/health/2009-07-12-veterans13_N.htm