Abstract
OBJECTIVE: We have conducted a study to clarify the association between amphetamine-related disorders (ARD) and the risk of developing dementia. METHODS: This study used a retrospective cohort design by using Taiwan's National Health Research Institute Database. A random sample of 68,300 subjects between January 1, 2000, and December 31, 2015, was obtained, comprising of 17,075 patients with ARD, and 51,225 controls without ARD (1:3), matched for gender and age group. After adjusting for covariates, a Fine and Gray's survival analysis (competing with mortality) was used to compare the risk of dementia during a 15-year follow-up period. RESULTS: In the present study, 1,751 of 17,075 patients with ARD and 2,147 of 51,225 in the control group without ARD (883.10 vs 342.83 per 100,000 person-years) developed dementia. ARD cohort was more likely to develop dementia (hazard ratio = 4.936 [95% CI: 4.609-5.285, P < 0.001). After adjusting for gender, age groups, education, monthly insured premiums, urbanization level, geographic region, comorbidities, the hazard ratio for ARD patients was 5.034 (95% CI: 4.701-5.391, P < 0.001). ARD has been associated with overall dementia, Alzheimer dementia, vascular dementia, and other dementia. Both the amphetamine use disorder and amphetamine-induced psychotic disorders were associated with the risk of overall dementia, Alzheimer dementia, vascular dementia, and other dementia. INTERPRETATION: This study shows that patients with ARD, both the amphetamine use disorder and the amphetamine-induced psychotic disorder, may have a nearly fivefold risk of developing dementia, including Alzheimer dementia and other types of dementia.