Can Glucocorticoids Induce Dementia?
Currently, the scientific evidence does not link the use of glucocorticoids to dementia definitely. There is a lot of inconsistency regarding their use and dementia, while some studies suggest a lower risk of dementia, others report the opposite. Regardless, chronic use or high-dose use of glucocorticoids is not recommended.
What Are Glucocoricoids?
Glucocorticoids are a class of steroid hormones. They are involved in various physiological processes.
Glucocorticoids are naturally produced in the hypothalamic-pituitary-adrenal axis. From there, they mediate the immune and metabolic systems [1].
Often they act as pacemakers between the pro-inflammatory and anti-inflammatory activities, therefore they can be thought of as the regulators of the immune system [2].
For instance, synthetic glucocorticoids are used in clinical practice to treat a number of inflammatory conditions and diseases like lupus and rheumatoid arthritis [1]. In clinical use, they are mainly used for their anti-inflammatory effect.
However, they also have a significant impact on metabolism. Glucocorticoids can stimulate gluconeogenesis in the liver, where they mobilize amino acids from extrahepatic tissues. By this, they inhibit the glucose uptake in muscle and adipose tissue and stimulate fat breakdown in adipose tissue [3].
Although glucocorticoids can have therapeutic effects, in high doses or over a long period, they can negatively impact our health. It leads to effects such as steroid-induced skeletal muscle loss, visceral adiposity, and diabetes development [1].
How Do Glucocorticoids Affect Our Body?
Glucocorticoids are steroid hormones that play a crucial role in various physiological processes, including metabolism, inflammation control, and stress response [1, 3, 4]. When glucocorticoids are administered pharmacologically, they exert potent immune-suppressive and anti-inflammatory effects[3].
As mentioned, they also impact our metabolism and contribute to the fat breakdown in adipose tissue [3].
In the musculoskeletal system, they increase bone resorption and decrease formation, which leads to bone loss, microarchitectural deterioration, and increased risk of fractures. Furthermore, they can also lead to loss of muscle mass and strength.
Therefore it is crucial to remember that chronic or high doses of glucocorticoids can significantly impact your health. It can lead to glucose intolerance, reduction in insulin sensitivity, or contribute to the development of diabetes. Apart from this it can also promote obesity [5], and cause changes in the peripheral blood white cell counts (this is mainly because they are involved in the regulation of the proliferation, differentiation, and apoptosis of these cells [6].
In conclusion, while GCs are vital for various physiological processes, their excess or long-term use can lead to detrimental effects on the body, affecting multiple organs and systems.
Can Glucocorticoids Cause Dementia?
This is an interesting question, as the relationship between glucocorticoids and dementia is quite complex and multifaceted.
Some studies suggest that the use of glucocorticoids can lower the risk of dementia. For example, in a study from Germany, analyzing health insurance data, they found that the risk of dementia was significantly lower for glucocorticoid users compared to non-users. Interestingly, the lowest risk was found in patients who inhaled glucocorticoids [7].
However other studies reported the opposite and suggested the phenomenon known as “steroid dementia syndrome”. As such, the glucocorticoid treatment was associated with cognitive changes characterized by impaired focus, and problems with concentration and memory, which are also present in dementia [8, 9].
Other research shown that the long-term use of glucocorticoids impacts the brain structure in particular the hippocampus and amygdala. The glucocorticoids were associated with brain atrophy in these structures and since these areas of the brain are responsible for memory and cognitive function, the atrophy brings us back to the steroid dementia syndrome [10].
Furthermore, studies looking at the Alzheimer’s disease model, showed that glucocorticoids have been found to worsen the cognitive impairments present in these models. Also, high levels of glucocorticoids lead to memory impairments and increased expression of amyloid precursor protein (a protein involved in Alzheimer's disease) [11, 12].
To summarize, while some studies suggest that glucocorticoids lower the risk of dementia, others suggest the opposite and propose even worsening of dementia when taking glucocorticoids. Therefore, more research is needed in order to determine the exact mechanism by which glucocorticoids act and affect the brain. In case you have a worry about glucocorticoids inducing dementia, always consult with your medical provider.