The PLoS ONE science journal published an interesting study performed by the Brain and Aging Research Program at the University of New South Wales in Sydney, Australia. The study sampled apolipoprotein levels in blood samples from over 600 older adults participating in the ongoing Sydney Memory and Aging Study.
Apolipoproteins are proteins that transport cholesterol and fats in the blood stream. There are several types of these proteins in the human body, and researchers were able to identify that lower levels of the apolipoproteins ApoA1, ApoA2 and ApoH levels, and higher ApoB/ApoA1 ratios increased the risk of cognitive decline over two years in cognitively normal individuals.
This is all still in the research phase, but it points the way to a future screening tool for Alzheimer’s that can reasonably be administered in a primary care setting, aka the doctor’s office. In addition to an independent study that will be needed to validate the Sydney findings, there is still a lot of work to be done in hammering out what “normal” reference ranges are for apolipoprotein levels.
Consider the following typical blood screening test result:
The last column lists blood component “reference ranges”, or what are considered normal levels, based on age range and gender. These blood panel reference ranges were established and validated through a 20 year medical research effort that began in the 1960s.
Reference ranges do not exist yet for apolipoprotein levels in the blood. In practical terms, this means a validated, reliable blood test for Alzheimer’s Disease is still several years away. But the basic research described in the PLoS ONE journal moves us a few steps closer.