FDA OKs first blood test that can help diagnose Alzheimer's disease U.S. health officials have endorsed the first blood test that can help diagnose Alzheimer’s. The test would help identify patients who may benefit from drugs that can modestly slow the memory-destroying disease. apnews.com/article/alzheimers-blood-test-fda-leqembi-kisunla-ad3cffe0bd540accf47e8ee105b439a9