Dementia is a common and disabling disease that affects the brain. The number of people with dementia is growing worldwide and is expected to triple by 2050. There are currently over 55 million people with dementia worldwide, and nearly 10 million new cases of dementia develop each year.
A new population-based study, published in BMC Medicine, led by researchers from the Karolinska Institute in Sweden has found a common first-line class of medications prescribed to dementia patients for depression could be hastening their cognitive decline, while also putting individuals at greater risk of fractures and earlier death.
As per the study, the more severe the dementia, the stronger the association between antidepressant use and cognitive decline.
What does the study say?
Dementia is typically associated with severe loss of memory and cognitive function and can range in severity from mild to severe, where a person may need complete assistance with daily activities. It is often accompanied by a variety of other psychiatric symptoms, such as anxiety, sleep loss, and depression. Especially likely in people over the age of 65, dementia is a progressive, neurological disease that may present as forgetting things, feeling anxious, struggling to make decisions, and more.
The new study suggests the use of antidepressants may hasten the cognitive decline of people with dementia. It’s a conclusion that some experts consider unwarranted.
Though other factors can't be conclusively ruled out, the possibility that some antidepressants might worsen an underlying condition may be important for medical specialists treating dementia patients to consider.
As per senior study author Sara Garcia Ptacek, an assistant professor in neurosciences at the Karolinska Institute in Solna, Sweden, “We found that patients with dementia who took antidepressants had greater cognitive decline over time.”
However, Ptacek also mentioned that patients and their caregivers should not overreact to the findings as the study was observational and more research needs to occur.

The findings:
Selective serotonin reuptake inhibitors (SSRIs) and serotonin norepinephrine reuptake inhibitors (SNRIs) are considered the first choice in antidepressants thanks to having relatively few side effects. Yet recent research has identified an association between the inhibitors and an increased risk of dementia in older adults, compared with psychotherapy.
While some classes of antidepressants risk interfering with processes responsible for our ability to think and recall our past, SSRIs have been considered to be largely helpful in protecting brains from neurodegeneration, even linked to reducing plaques thought to play a role in damaging brain cells.
Reconciling these seemingly contradictory findings in the population has itself failed to reveal a definitive answer, potentially because of the type of data collected and limitations in the way results were gathered.
The researchers also found a concerning rise in the risk of fractures that could be associated with higher SSRI doses, which may indicate unwanted neurological interference too, as do their results hinting at an increase in all-cause mortality.
The study failed to find any such link with SNRIs, suggesting differences in their mechanisms or possibly a limitation in the study itself. Future research could provide clarity on the risks and benefits of each class of antidepressant.

The fraternity’s take:
Experts not involved with the study agree the study’s findings should be interpreted with caution.
Dr. Prasad Nishtala, a reader in the department of life sciences at the University of Bath in the United Kingdom, said in a statement, “The severity of depression in dementia patients wasn’t fully accounted for, which has the potential to bias the results.”
Preventive neurologist Dr. Richard Isaacson, director of research at the Institute for Neurodegenerative Diseases in Boca Raton, Florida, said doctors who treat dementia aren’t likely to change their practices based on this study.
Isaacson told CNN, “As a clinician, the worrisome thing is that a patient’s loved one will hear about this study and say, ‘Oh if we use an antidepressant, my mom will decline faster’. Then what happens to the patient’s quality of life? Could they become more agitated and be a danger to be kept at home? Could they become more withdrawn, socially restricted and apathetic? Very probably.”
He also added, “A major limitation of the study is that the researchers didn’t know if the people that needed antidepressants were more severe and more likely to decline in the first place.”
More importantly, as per Isaacson, tests of cognitive decline administered during the study showed patients on commonly used antidepressants actually declined more slowly than what is typical for dementia patients overall.

What is dementia?
Dementia is a syndrome that causes a decline in cognitive abilities, such as thinking, remembering, and reasoning, that interferes with daily life. It's a loss of brain function that can be caused by several diseases that damage nerve cells. Dementia is more common as people age, but it's not a normal part of aging.
Dementia can have a significant impact on people with the disease, their families, carers, and society. There's often a lack of awareness and understanding of dementia, which can lead to stigma and barriers to diagnosis and care.