Steroids Commonly Used for Asthma and Allergies Linked to Changes in Brain Structure, Study Shows

The white matter of the brain and cognitive impairment have been linked to glucocorticoids, a common steroid used to treat inflammation related to asthma and allergies.

The latest study, published in BMJ Open, indicated that both inhaled and orally administered glucocorticoids had similar effects on brain structure. The authors of the study noted that it was the largest of its type to date.

"Both systemic and inhaled glucocorticoid use were associated with reduced white matter integrity," the study concluded.

White matter is the connective tissue between brain cells and the rest of the nervous system, and it may be found in the deeper brain tissues. Damage to white matter has been linked to difficulties with learning, memory, and gait. Depression, anxiety, and even bipolar disease have all been related to white matter damage.

The implications of this result and how it affects glucocorticoid use are discussed in further detail below.

Oral and Inhaled Glucocorticoids Both Trigger Brain Decline

Glucocorticoids, commonly prescribed drugs with immunosuppressive properties, are widely used to treat conditions such as allergies, asthma, and autoimmune disorders. However, a recent study examined the effects of glucocorticoid use on the brain and found a link between the medication and reduced white matter.

The study analyzed data from individuals who used oral or inhaled glucocorticoids and compared it to a control group of individuals who did not use these medications. The participants underwent cognitive and mental health tests as well as brain MRIs. The results revealed that taking either oral or inhaled glucocorticoids was associated with a reduction in white matter in the brain.

This reduction in white matter has the potential to lead to neuropsychiatric side effects, especially in individuals who use these medications regularly. The study noted that the impact on white matter was more significant in those who used glucocorticoid tablets or injections over a long period of time, while those who used inhalers or nasal glucocorticoids experienced a smaller impact.

The exact reasons behind the impact of glucocorticoids on white brain matter are not yet clear, according to the study’s lead author. However, the findings suggest that chronic exposure to glucocorticoids may have detrimental effects on white matter in various organs of the body, including the brain.

Further research is needed to better understand the underlying mechanisms and implications of these findings. In the meantime, it is important for healthcare professionals to consider the potential neuropsychiatric effects of glucocorticoid use, especially with long-term or high-dose administration.

Are the Findings Cause for Concern?

While the recent study suggests a link between glucocorticoid use and reduced white matter in the brain, experts have emphasized that the results should not cause undue concern. According to Dr. Kesari, white matter can potentially repair itself even in the presence of glucocorticoids, and the brain appears to recover when patients are taken off these medications.

It is important to note that the study did not specifically investigate the long-term impacts of glucocorticoid use on white brain matter. Previous research has associated long-term oral glucocorticoid use with brain shrinkage in certain areas and changes in brain structure. Mental health issues have also been linked to this class of drugs.

The consequences of the observed changes in white matter and their impact on patients are still unknown. The reversibility of these changes remains to be determined. As Jamie Alan, PhD, an associate professor of pharmacology and toxicology, pointed out, there is still much to learn about the effects of glucocorticoids on the brain.

What Should You Do if You Use Glucocorticoids?

Given the minimal changes observed in white matter, Van der Meulen advised against patients abruptly changing their medication based on the study findings. The small structural changes found in the study are likely to have no significant functional side effects for many individuals with asthma.

Other medical professionals echoed similar advice. They emphasized the importance of using glucocorticoids for the shortest duration possible due to their known side effects. The study supports the clinical guideline of minimizing the use of glucocorticoids when feasible.

Dr. Kesari acknowledged the beneficial anti-inflammatory properties of glucocorticoids and their widespread use in treating various conditions. He highlighted the need for a better understanding of their side effects and more effective mitigation strategies.

If a person is on a high dose of glucocorticoids for an extended period, Dr. Kesari suggested discussing with their doctor the possibility of reducing the dosage or exploring alternative treatments that may have less impact on the body and brain.

However, it is important to note that van der Meulen strongly advised against making changes to medication without consulting a healthcare provider. If a person requires the medication, they should continue taking it as prescribed until they have discussed any concerns with their doctor.