Background: Recent evidence indicates an important role for neuroinflammation in the pathological cascade of Alzheimer's disease (AD), and neuroinflammation is increasingly being recognized as a potential therapeutic target.
Objective: To assess the impact of glucocorticoids on the risk of developing dementia.
Methods: We used health insurance data of the largest German health insurer from 2004-2013 with a baseline sample of 176,485 persons aged 50 years and older to study the association of glucocorticoid treatment and incidence of dementia. Cox proportional-hazard models were calculated adjusting for sex, age, and comorbidities known to be major risk factors for dementia and were given as hazard ratios (HR) with 95% confidence intervals (CI). We further stratified glucocorticoid treatment by route of application and treatment duration.
Results: Of the 176,485 dementia-free persons, 19,938 were diagnosed with dementia by the end of 2013. The risk of suffering from dementia was significantly lower for glucocorticoid users compared to non-users (HR = 0.81, CI = 0.78-0.84). The lowest risk was found among users of inhaled glucocorticoid (HR = 0.65, CI = 0.57-0.75), followed by nasal (HR = 0.76, CI = 0.66-0.87), other (HR = 0.84, CI = 0.80-0.88), and oral users (HR = 0.83, CI = 0.78-0.88). We found no difference in risk reduction between long- and short-term-users.
Conclusion: Longitudinal German health insurance data indicate that the use of glucocorticoids is associated with a lower risk of dementia. Prospective clinical trials will be necessary to determine whether glucocorticoids can have a positive impact on neuroinflammation and thus protect persons against dementia.
Keywords: Administrative claims; cohort studies; dementia; epidemiology; glucocorticoids; inflammation.