Trends in dementia incidence and mortality, and dynamic changes in comorbidity and healthcare utilization from 2004 to 2017: A Taiwan national cohort study

Abstract

AimsThis study aims to ascertain dementia incidence from 2004 to 2017 in Taiwan, and to examine the disease course in comorbidity, treatments, healthcare usage, and mortality among older people with incident dementia preceding the diagnosis of dementia and afterwards. MethodsTaiwan National Health Insurance data on people aged ≥ 65 years with incident dementia from January 2004 to December 2017 were excerpted to estimate annual incidence rates and annualized percentage changes(APCs). For people diagnosed before 2013, annual mortality rates and causes of death during 5-years’ follow-up were determined. Changes in 22 diseases/conditions, hospital visits and admissions, and psychotropic medication prescriptions commonly associated with dementia, were examined from 3 years preceding the index diagnosis until 5 years afterwards. ResultsFrom 2004 to 2017, the annual incidence of dementia in Taiwan increased from 30,606 to 50,651, and by > 90 % in women; age-standardized annual incidence increased significantly, with an APC of 0.4 %(p = 0.02). For 372,203 incident cases from 2004 to 2013, annual mortality was∼12 % during 5-years’ follow-up. The prevalence of most comorbidities increased by 65–150 % after being diagnosed with dementia. People with incident dementia had increased healthcare usage 1 year before diagnosis, which peaked 1 year afterwards. Psychotropic medication prescriptions increased gradually over 3 years before diagnosis, peaked 3 months afterwards, gradually declined during the next 2 years, then remained stable. ConclusionThe incidence of dementia in Taiwan has increased gradually over time, with an annual mortality risk of∼12 %. Older people with dementia had more healthcare needs and comorbid conditions after dementia diagnosis, highlighting the exigency of person-centered dementia care.