A group led by the Mayo Clinic s Dr. Ronald Petersen developed a set of simple tests to try to get a reliable risk-predictor for cognitive decline, a harbinger of dementia. Their three-step methodology had a high rate of accuracy in predicting the onset of mild cognitive impairment (MCI) over the course of 5 years in a group of randomly selected older residents of Olmstead County, MD.
The Mayo group randomly selected almost 1,500 people in the vicinity of the Mayo Clinic, aged 70-89 years at the study s outset in 2004. All patients were cognitively normal initially. Over an average duration of 5 years, they assessed their patients every one to two years. The analysis consisted of three stages:
1-the simplest part was a compendium of known risk factors for Alzheimer s disease (AD): diabetes, smoking, family history, age, gender, high blood pressure.
2-the next phase requires a doctor s office visit, during which a mental status evaluation is done, including assessments for apathy, anxiety and depression, all of which have also been linked to AD later on. Additionally, and surprisingly, the speed at which a patient can walk a short distance was found to be an important risk predictor.
3-among those subjects whose risk calculus shows a higher score, a blood test for ApoE-epsilon-4 gene is done: this gene has been shown to confer a significantly increased risk of AD.
Over the course of the study, 401 (28 percent) developed MCI. The study subjects within the highest risk quartile had a seven-fold higher incidence of MCI than those in the lowest quartile.
So what good do such studies do, given the sad fact that we have nothing in our therapeutic armamentarium to stave off or treat AD? Dr. Petersen told FoxNews: While doctors are able to identify biomarkers for cognitive impairment using MRI and PET scans, they are expensive procedures...If we can characterize the general population out there as to who is at high, medium, and low risk we then will be able to allocate these more expensive and invasive procedures intelligently, he said.
ACSH s Dr. Gil Ross added this: Since AD develops insidiously over years, perhaps decades, before it becomes clinically apparent, waiting for signs to develop is too late. Medical research must have reliable early predictors of those who are highly likely to eventually get AD, in order to test various therapies to gauge efficacy. That s why these sorts of studies are important not for now, not for the next few years, but for the indefinite future when treatments are available that might slow this oncoming epidemic of vast proportions.
