A new study has found the kind of effect that prescribed steroids including inhalers can have on the brain. It states that the use can change the structure and volume of white and grey matter in the brain. 

The study, published in the journal BMJ Open, indicates what the associations found might help to explain the neuropsychiatric effects, such as anxiety, depression, mania, and delirium frequently seen after long-term use, say the researchers.

"This study shows that both systemic and inhaled glucocorticoids are associated with an apparently widespread reduction in white matter integrity, which may in part underlie the neuropsychiatric side effects observed in patients using glucocorticoids," said researchers, including Merel van der Meulen from Leiden University Medical Center.