Arad Kodesh, M.D., of the University of Haifa in Israel and colleagues analyzed the health records of 71,515 people aged 60 years or older from Israel. As far back as 2002, the participants had no diagnosis of dementia or record of taking medications for dementia. No participants had taken an antidepressant in 2012. The researchers then followed the participants from May 2013 to October 2017.
During follow-up, 3,688 participants had received and filled prescriptions for an antidepressant for at least 60 days. Of those, 11% developed dementia. In contrast, only 2.6% of those who did not take antidepressants developed dementia. After adjusting for other conditions linked to dementia risk, the researchers found that the risk of dementia in those who took an antidepressant was 3.43 times greater than those who did not.
“This is a considerable increase in risk and may be compared to other risk factors for dementia that have around a 1.6-fold increased dementia risk, e.g., smoking, and BMI [body mass index],” Kodesh and colleagues wrote.
The researchers found the increased risk to be consistent across different classes of antidepressants, with two notable exceptions: Compared with those who did not take antidepressants, those who took amitriptyline had twice the risk of developing dementia, and those who took paroxetine had more than five times the risk.
In noting the limitations of their study, the researchers wrote that their results could “mimic the [known] association between depression and dementia rather than the effect of taking an antidepressant.”
Nonetheless, they emphasized the importance of careful prescribing in older patients.
“Clinicians, caregivers, and patients may wish to consider this potential negative consequence of antidepressant exposure with the objective of balancing the adverse events and symptomatic benefits of monotherapeutic antidepressant medication in old age,” they wrote.
For related information, see the Psychiatric News article “Percentage of Americans Taking Antidepressants Climbs.”