A national survey of caregivers' perspective of early symptoms of dementia among adults with an intellectual disability based on the DSQIID scale

As life expectancy increases for persons with an intellectual disability, concerns have been raised that there will be an increased demand for health or social services, particularly to address the challenges posed by the problems of dementia. To plan services for people with an intellectual disability who might experience the consequences of aging, an important first step is to obtain epidemiological data on the prevalence of dementia in this vulnerable population. This study aimed to investigate the dementia prevalence rate and its associated demographical factors in adults with an intellectual disability in Taiwan. A national survey was conducted to recruit 460 community residents of at least 45 years of age with an intellectual disability. The Dementia Screening Questionnaire for Individuals with Intellectual Disabilities (DSQIID) was administered to caregivers to determine the symptoms of dementia in adults with an intellectual disability. The results indicated that 16.5% of the adults with an intellectual disability might have dementia conditions (DSQIID score ≫ 20). After controlling for other factors in a multiple logistic regression analysis, the older adults with intellectual disability (≧55 vs. 45-54, OR = 2.594, 95% CI = 1.438-4.679) and those individuals with a comorbid diagnosis of mental illness or neurological disease (with vs. without, OR = 2.826, 95% CI = 1.593-5.012) had a higher risk of dementia than their counterparts. This study suggests that further longitudinal studies are needed to examine the specific aspects of the functions of living and morbidity that might be affected by aging and concomitant conditions in adults with an intellectual disability.