Having depression is known to increase the risk for developing Alzheimer's disease.
However, a new study has found that depression and anxiety are linked to earlier onset of Alzheimer's disease (AD).
According to the study, if people do develop Alzheimer's disease, those with depression may start experiencing dementia symptoms about two years earlier than those who do not have depression.
The study also suggested that people with anxiety who develop Alzheimer's may start experiencing dementia symptoms about three years earlier than those who do not have anxiety.
The study will be presented at the American Academy of Neurology's 73rd Annual Meeting being held virtually from April 17 to 22, 2021.
Researchers also found a serial decrease in the age when symptoms first started that doubled with each additional psychiatric disorder diagnosis.
People with only one disorder developed symptoms about 1.5 years before those with no psychiatric disorders.
Those with two psychiatric conditions developed symptoms 3.3 years earlier than those with no conditions.
And those with three or more psychiatric disorders developed symptoms 7.3 years earlier than those with no such conditions.