IDD and Dementia. Section 2: Introduction


Although it is well known that older people are at higher risk for Alzheimer's disease and dementia, it is less well known that individuals with intellectual disabilities, especially Down syndrome, are also at high risk of the disease. The need for enhanced community-based support for persons with intellectual disabilities and dementia and their caregivers will expand as the overall population ages. With the aging of the population, the number of older people will increase significantly over the next 20 years, a trend that will be mirrored among older adults with an intellectual disability (National Task Group on Intellectual Disabilities and Dementia Practice [NTG], 2012). Age-related health problems among people with intellectual disabilities are similar to those in the general population, including the development of dementia in later life (Heller et al., 2010; May & Kennedy, 2010; McCallion et al., 2013).

The prevalence of dementia in people with Down syndrome at middle and early elderly ages is higher than in the general population (Ball et al., 2008; McCarron et al., 2014). Chromosome 21 plays a key role in the relationship between Down syndrome and Alzheimer's disease as it carries a gene that produces one of the key proteins involved with changes in the brain caused by Alzheimer's (Moran, 2013). Adults with Down syndrome experience "accelerated aging," where certain conditions and physical features that are common for aging adults occur at an earlier age than the general population (Moran, 2013).

This paper aims to provide the community of providers who primarily serve older people with a broad overview of the services and support system needed by persons with intellectual and developmental disabilities (IDD) who also have dementia. It provides background information on the prevalence, characteristics, diagnosis, and treatment of dementia for persons with IDD. The paper provides a description of the types of long-term services and supports (LTSS) provided and paid for by both public and private funding sources and examples of initiatives to build cross-population dementia capability.

This paper makes frequent use of the term intellectual and developmental disabilities (IDD). Intellectual disability is defined as a disability that originates before age 18 and is characterized by significant limitations in both intellectual functioning and in adaptive behavior, which includes many everyday social and practical skills. Determining if a person has an intellectual disability is complex. An IQ test can be used to measure limitations in intellectual functioning. Limitations in adaptive behavior can be measured by evaluating conceptual, social, and practical skills. (American Association on Intellectual and Developmental Disabilities [AAIDD], 2013). The most common syndromes associated with intellectual disability are autism, Down syndrome, Fragile X syndrome, and Fetal Alcohol Spectrum Disorder (The Arc, 2015).

The term developmental disability means a severe, chronic disability of an individual that is attributable to a mental or physical impairment or combination of mental of physical impairments; is manifested before the individual attains age 22; is likely to continue indefinitely; results in substantial functional limitations in three or more of the following areas of major life activity: Self-care; Receptive and expressive language; Learning; Mobility; Self-direction; Capacity for independent living. Also, reflects the individual's needs for a combination and sequence of special interdisciplinary, or generic services, individualized supports, or other forms of assistance that are of lifelong or extended duration and are individually planned and coordinated (Developmental Disabilities Assistance and Bill of Rights Act of 2000). Developmental disability encompasses intellectual disability but also includes physical disabilities, such as cerebral palsy, traumatic brain injury, and epilepsy (AAIDD, 2013). Developmental disabilities can be identified through a process of developmental monitoring and developmental screening. Physicians examine children at their well-child visits for developmental delays, termed developmental monitoring. If any problems are identified, developmental screening can be conducted through the use of short tests to determine if learning is typical or delayed (CDC, 2015).

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