Routine blood test may detect Alzheimer's: study

Jerusalem: A routine blood test that uses a neuroprotective protein as a biomarker may effectively diagnose Alzheimer's disease, a new study has found.

Researchers from Tel Aviv University (TAU) in Israel and Harvard University in US have proposed a new biomarker for cognitive ageing and Alzheimer's disease: activity-dependent neuroprotective protein (ADNP), the levels of which can be easily monitored in routine blood tests.

The study also found that ADNP levels tested in the blood correlate with higher IQ in healthy older adults. Medical professionals have to conduct a long series of tests to assess a patient's memory impairment and cognitive skills, functional abilities, and behavioural changes to accurately diagnose Alzheimer's disease.

They also have to execute costly brain imagining scans and even, sometimes, invasive cerebral spinal fluid tests to rule out other diseases. The process is laborious at best - and subjective at worst.

For the study, researchers analysed blood samples taken from 42 healthy adults, mild cognitive impairment (MCI) patients, and Alzheimer's disease patients. After comparing the ADNP expression in the blood samples,
they prepared plasma samples and once again compared the protein levels.

Significant increases in ADNP RNA levels were observed in patients ranging from MCI to Alzheimer's. ADNP levels tested in plasma and serum samples, as well as white blood cell RNA levels, distinguished among cognitively normal elderly, MCI, and Alzheimer's dementia participants.

"This study has provided the basis to detect this biomarker in routine, non-invasive blood tests, and it is known that early intervention is invaluable to Alzheimer's patients," said Illana Gozes from TAU.

"The more ADNP RNA found in the blood cells, the fewer aggregates found in the brain of elderly cognitively normal individuals. Interestingly, we also found that the more ADNP in the serum, the higher the person's IQ level," Gozes said.

"We are now planning to take these preliminary findings forward into clinical trials - to create a pre-Alzheimer's test that will help to tailor potential preventative treatments," she added. The findings were published in the Journal of Alzheimer's Disease.