Patterns of anti‐inflammatory drug use and risk of dementia: a matched case–control study

Background and purpose There is limited primary‐care‐based evidence about a potential association between anti‐inflammatory therapy and dementia subtypes. The present study addressed this limitation by using electronic health records from a large primary care database. Method A case–control study was implemented using electronic medical records. Cases had a diagnosis of dementia between 1992 and 2014. Up to four controls matched on age, gender, family practice and index date were selected for each case. Use of non‐steroidal anti‐inflammatory drugs ( NSAID s) and glucocorticoid drugs represented the exposure variables. Primary outcome measures included all‐cause dementia and main dementia subtypes, including Alzheimer disease ( AD ), vascular dementia (VaD) and Lewy body dementia ( LBD ). Data were analysed using conditional logistic regression. Results The study identified 31 083 patients with AD , 23 465 with VaD and 1694 with LBD . Ever‐used NSAID s were associated with a modest increase in the risk of all‐cause dementia (odds ratio 1.04, 95% confidence interval 1.02–1.05, P  < 0.006), whilst no association was apparent for ever‐used glucocorticoids (0.98, 0.96–1.01, P  = 0.152). There was no evidence for an association between NSAID s and AD (1.03, 0.99–1.06, P  = 0.07) or LBD (1.13, 0.99–1.29, P  = 0.08). However, a significant increase in the risk for VaD (1.33, 1.29–1.38, P  < 0.001) was observed. Similar patterns emerged for glucocorticoid therapy. Conclusion In a large primary care population, there was no robust evidence for a potential association between anti‐inflammatory drugs and risk of AD or LBD. NSAID s and glucocorticoid drugs were associated with higher risk of VaD.