Dose-Responsive Effect of Psychotropic Drug Use and Subsequent Dementia: A Nationwide Propensity Score Matched Case-Control Study in Taiwan.

Abstract: Objective: To test the hypothesis that the load of psychotropic agents was associated with subsequent dementia occurrence by a nationwide database. Design: Propensity score matched case-control study. Setting: National Health Insurance Research database. Participants: A total of 32,649 older people with dementia and 32,649 matched dementia-free older people. Measurements: Use of psychotropic drugs (anxiolytics, antipsychotics, hypnotics, and antidepressants), defined daily dose (DDD) of psychotropic drugs, diagnosis of dementia, and propensity score. Intervention: None. Results: Compared with nonusers, ever use of psychotropic agents was associated with higher odds of subsequent dementia [adjusted odds ratio (OR): 3.73; 95% confidence interval (CI) (3.59–3.88)]. Significantly, the association was stronger with longer term exposure to psychotropic agents. The ORs at exposures of <90 days, 90–180 days, and >180 days, were 3.14 (95% CI 3.01–3.28); 5.48 (5.07–5.93); and 7.54 (6.73–8.44), respectively. A similar and stronger association was identified when cumulative dose was used to measure the exposure of psychotropic agents [<90 DDDs, 3.40 (95% CI 3.26–3.54); 90–180 DDDs 6.38 (5.76–7.07), and >180 DDDs, 7.35 (6.29–8.58)]. Conclusions: We found that a higher burden of psychotropic agents was strongly associated with a higher odds of subsequent dementia. Careful monitoring of any elderly who is prescribed or uptitrated psychotropic agents is highly recommended, especially those who combine use of more than one agent. Furthermore, providing timely assessment for cognitive function for older patients consuming psychotropic drugs is of great importance. [Copyright &y& Elsevier]