We started off the year full of promise in our quest for some way to diagnose Alzheimer's disease when studies demonstrated the promise of florbetapir and plasma beta amyloid. However, in a retrospective case control study published yesterday in the Archives of General Psychiatry, the authors concluded that biomarkers were of no benefit in predicting the conversion of 116 patients with mild cognitive impairment (MCI) to Alzheimer's disease (AD) compared to 204 controls w/MCI who did not convert to AD over a 2 year period of time.
Instead, cognitive testing accounted for 50% of the conversion from MCI to AD, which is why, in my presentation, I recommend testing cognitive function each and every time a patient comes in for an evaluation, even if it's unrelated to his/her MCI. I figure the more data points the better. Of course, measurement of middle temporal lobe cortical thickness also helped in predicting conversion of MCI to AD. However, cognitive testing is a heck of a lot cheaper when you're talking about following millions of patients. Just something to think about in our current dysfunctional medical system . . . And thank you to my colleague, Dr. Sandy H, for pointing out this study!