New York: Researchers have developed a blood test that leverages the body's immune response system to detect an early stage of Alzheimer's disease - referred to as the mild cognitive impairment (MCI) stage. "To the best of our knowledge, this is the first blood test using autoantibody biomarkers that can accurately detect Alzheimer's at an early point in the course of the disease when treatments are more likely to be beneficial,” said lead researcher Robert Nagele from Rowan University School of Osteopathic Medicine in Stratford, New Jersey. He is also the co-founder and chief scientific officer of New Jersey-based Durin Technologies, Inc. In a "proof of concept" study involving 236 participants, the test demonstrated an overall accuracy, sensitivity and specificity rate of 100 percent in identifying patients whose mild cognitive impairment (MCI) was actually caused by an early stage of Alzheimer's disease. About 60 percent of all MCI patients has MCI caused by an early stage of Alzheimer's disease. The remaining 40 percent of cases are caused by other factors, including vascular issues, drug side-effects, and depression, according to the study. "To provide proper care, physicians need to know which cases of MCI are due to early Alzheimer's and which are not," said the study's lead author Cassandra DeMarshall, Ph.D. candidate at Rowan University Graduate School of Biomedical Sciences. "Our results show that it is possible to use a small number of blood-borne autoantibodies to accurately diagnose early-stage Alzheimer's,” DeMarshall noted. "These findings could eventually lead to the development of a simple, inexpensive and relatively non-invasive way to diagnose this devastating disease in its earliest stages," DeMarshall said. The study appeared in the journal Alzheimer's & Dementia where the researchers reported the test's ability to accurately "stage the disease," meaning it can distinguish early-stage Alzheimer's at MCI from later, more advanced stages. According to the authors, early diagnosis of Alzheimer's disease and the ability to stage the disease through a simple blood test would offer many potential benefits. Patients could possibly delay disease progression through lifestyle adjustments, begin treatment sooner and plan future medical care. Clinicians would have a way to measure the effectiveness of therapeutic intervention and clinical trials could enroll patients who were truly at the earliest stage of their disease.