Depression Doubles Risk of Dementia in Later Life

A recent study published in JAMA Neurology reveals that individuals diagnosed with depression during early or mid-adulthood are more than twice as likely to develop dementia as they age.

The comprehensive study, which examined over 1.4 million adult Danish citizens from 1977 to 2018, found that those with a history of depression were 2.4 times more prone to developing dementia compared to their non-depressed counterparts. Interestingly, the risk of dementia was observed to be higher in men than women.

The study suggests that the persistent correlation between depression and dementia diagnosed earlier in life indicates an increased likelihood of developing dementia. However, it does not provide clear reasons behind this link.

Dementia refers to a broad term encompassing the inability to remember, think clearly, or make decisions that impede everyday activities, according to the Centers for Disease Control and Prevention (CDC).

Contrary to previous beliefs that depression diagnosed later in life was merely an early symptom or response to the preclinical stage of dementia, this study focused on exploring whether depression diagnoses in early and middle adulthood were linked with dementia. It found a strong association between depression at any point in adulthood and subsequent dementia.

Interestingly, the use of antidepressants did not appear to affect the risk of developing dementia, as there was no significant difference between those who received treatment and those who did not.

The study also noted that the risk of dementia was doubled for both men and women diagnosed with depression, with men potentially presenting more severe cases due to their tendency to seek healthcare services less frequently.

Currently, approximately 5.8 million people in the United States are affected by Alzheimer's disease and related dementias, according to the CDC. Alarmingly, this number is predicted to rise to approximately 14 million individuals by 2060, with minority populations being disproportionately impacted.

It is crucial that further research is undertaken to better understand the relationship between depression and dementia. By elucidating the underlying mechanisms, healthcare professionals can develop strategies to mitigate the risk of dementia in individuals with a history of depression.