Depression and Dementia

The global population is aging, especially in industrialized countries.

According to the World Health Organization, by the year 2050, the proportion of people over 60 years old will have doubled. This can be explained because, on one hand, we are living longer, and on the other, people are having fewer children. As expected, this fact has significant consequences on various levels (social, economic, and also in terms of healthcare).

Therefore, given the increasing importance of this population sector, I would like to dedicate a few words to them from the perspective of mental health.

It is estimated that at least 20% of people over 60 years old suffer from some form of mental or neurological disorder. The most significant examples are depression and dementia.

Many patients with late-onset depression (in other words, at an advanced age) who do NOT exhibit cognitive impairment eventually develop dementia within three years, according to a well-known 1985 study. What is happening? Does late-life depression really pose a risk factor for developing dementia? Or is it perhaps that dementia often begins subtly, slowly and progressively and shares many symptoms that are also present in late-life depression? It could be a bit of both.

For example, many Alzheimer’s patients experience depression, especially at the onset of the disease. At the same time, a person with advanced Alzheimer’s may not be able to express how they feel, and they may be depressed, even if we are unable to detect it, or other disturbances may be much more disruptive and draw more of our attention.

Symptoms that appear in both depression and Alzheimer’s disease include memory impairment, difficulty concentrating, social withdrawal, changes in sleep patterns (oversleeping or insomnia), and a loss of interest in activities that were once pleasurable. So, how can we distinguish between them? Sometimes, it’s challenging.

Typically, it is said that individuals with dementia are less aware of their memory problems, etc., and it’s usually their family who brings them to the clinic. In contrast, when it comes to depression, the patient often seeks help themselves, reporting subjective complaints of memory or concentration issues. This could be a useful hint in clinical practice, although not definitive. Imaging tests like brain CT scans or MRIs are not conclusive, especially in the early stages of dementia, so they offer little help in this regard. Therefore, clinical assessment (the signs and symptoms) and close monitoring play a more significant role in the early diagnosis.

There is no doubt that depression is highly prevalent in individuals with dementia, although the relationship between the two is not entirely clear; depression might even be a risk factor for dementia.

In any case, it’s essential to treat depression in dementia to improve the functionality and cognition of the affected patients. Here, we encounter a new factor to consider when treating these patients: typically, individuals with dementia are elderly and may have other associated medical conditions and treatments. Therefore, it is vital to choose medications that have a lower risk of interacting with other treatments, take into account the side effects profile for better patient tolerance, and, last but not least, ensure that the treatment doesn’t worsen the patients’ cognition. What if, instead of worsening, we manage to even enhance their cognitive function?

In recent years, new antidepressants with favorable cognitive profiles have been introduced to the market. As examples, I should mention tianeptine (Zinosal), agomelatine (Valdoxan or Thymanax), and vortioxetine (Brintellix). The fact that these medications appear in the latest clinical practice guidelines in geriatrics as good options for the elderly is not a coincidence. This is precisely because they meet these three key considerations when treating depression in the elderly, in addition to their antidepressant efficacy: they have a positive cognitive profile, a good side effects profile (they are generally well-tolerated in the elderly), and a good interactions profile (so there is no issue with them taking other types of treatments for other existing conditions).

Next time, I will tell you about the properties of Tianeptine, an antidepressant with a different mechanism of action and interesting advantages compared to other treatments.

Have a great Sunday, and take care of your elders!