Is your elderly grandfather showing higher levels of anxiety? Beware, it may signal the early manifestation of Alzheimer's disease, researchers warned. Alzheimer's disease is a neurodegenerative condition that causes the decline of cognitive function and the inability to carry out daily life activities.

The findings showed that worsening anxiety symptoms in older adults with may be associated with an increase in amyloid beta levels -- a key factor in the development of Alzheimer's disease.