Arthur J. Dalton

Mortality and morbidity among older adults with intellectual disability: health services considerations

PURPOSE Described is a study of the mortality and morbidity characteristics of 2752 adults with intellectual disability, age 40 and older, who died over a 10 year period in one American state. RESULTS The main finding was that although individuals in the current generation of older adults with intellectual disability still generally die at an earlier age than do adults in the general population (average age at death: 66.1 years), many adults with intellectual disability live as long as their age peers in the general population. The results suggest that the longevity of adults with intellectual disability, whose aetiology is not attributable to organic causes, is progressively increasing. The results also confirm an increased longevity for adults with Down syndrome (average age at death: 55.8 years). Findings also showed that the causes of death for the study cohort were similar to those of the general older population, with cardiovascular, respiratory and neoplastic diseases among the most prominent causes of death. CONCLUSIONS It was proposed that clinical and prophylactic health practices could have significant social and health care consequences for delaying the onset or minimizing the occurrence of life threatening diseases (and thus prolonging life) in adults with intellectual disability. It was suggested that clinical practices could be implemented that deter the onset and lessen the impact and burden of older age-related diseases and secondary conditions and that greater attention needs to be given to training of health care professionals in the area of geriatric medicine and intellectual disability.

Sensory impairments among older adults with intellectual disability

The extent of vision and hearing impairment was evaluated in a study of 45,500 adults with an intellectual disability, 35 years of age and older. Visual impairment or blindness was recorded in 25% of adults in the total sample, 21% of adults aged 35 to 59 years, 36% of adults aged 60 to 79 years, and 50% of adults aged 80 and older. Impaired hearing or deafness was recorded in 22% of adults in the total sample, 16% of adults aged 35 to 59 years, 35% of adults aged 60 to 79 years, and 62% of adults aged 80 and older. The results indicated a prevalence among adults with intellectual disability comparable to or greater than that found in the general population and that these sensory deficits occurred with increasing frequency with advancing age. These findings point to the need to heighten awareness among staff and other carers about vision and hearing problems, and the consequent problems which may develop in interpersonal, communication, and adaptive functioning. Findings also support general screening for...

Dementia-Related Care Decision-Making in Group Homes for Persons with Intellectual Disabilities

Abstract Alzheimers disease and related dementias affects a significant number of adults with intellectual disability (ID), in particular those with Down syndrome. Many affected adults live in small community group homes or with their families. How to provide sound and responsive community care is becoming a challenge for agencies faced with an increasing number of affected adults. This study reports the outcome of a survey of group homes serving adults with ID and dementia, explores the onset, duration and effects of dementia, and speaks to the impact of these on planning for community care of adults with ID. It also examines emerging community care models that provide for “dementia capable” supports and services. Two models, “aging in place” and “in place progression” are examined, as well as “referral out” reactions, with regard to care practices and critical agency decision making. A programmatic approach, the ECEPS model, for responding to dementia is offered.

Plasma amyloid β protein 1-42 levels are increased in old Down syndrome but not in young Down Syndrome

Plasma amyloid beta protein 1-40 (Abeta40) and Abeta42 levels were quantitated from 28 young Down syndrome (DS) (20-40 years old), 28 age-matched controls, 32 old DS (41-65 years old) and 32 age-matched controls in a sandwich enzyme-linked immunosorbent assay. Abeta40 levels were higher in young DS and old DS than controls. Abeta42 levels in young DS and controls were similar, however Abeta42 levels were higher in old DS than controls or young DS. The higher Abeta42 levels in old DS suggests that Abeta42 is selectively increased in plasma concurrently with the development of Alzheimer disease neuropathology.

Group home care for adults with intellectual disabilities and Alzheimer’s disease

The growing numbers of individuals with intellectual disabilities affected by Alzheimer’s disease and related dementias has raised new challenges for community care providers. This article examines means of providing community group home-based care in a sample of care providers in five different countries. The aim is to identify trends that have emerged. Two samples of group homes for adults with intellectual disabilities affected by dementia were studied to determine: (1) what are the physical characteristics of the homes; (2) what physical environmental adaptations have been made in response to behavioral deterioration expressed by residents with dementia; and (3) what are the demands on staff resulting from dementia care. The first sample of group homes in five countries provided comparative international data on home designs, staffing, costs, and residents. The second sample, drawn from homes in the USA and the UK, provided data on the impact of dementia. Findings revealed staffing and design of homes varied but generally abided by general practices of dementia care; homes relied on existing resources to manage changes posed by dementia care; programmatic and environmental adaptations were implemented to address progression of dementia; and residents with dementia presented more demands on staff time with respect to hygiene maintenance and behavior management when compared to other residents not affected by dementia.

Cognitive changes in memory precede those in praxis in aging persons with Down syndrome

Experimental tests of cognitive functions were developed and standardised to detect the onset and progression of the early stage of Alzheimer disease in persons with Down syndrome. The aim was to determine whether or not there was a specific sequence of cognitive changes over a 3-year period for the test measures. When compared with a young group (17–39 years of age at the start), an old group of persons with Down syndrome (40–58 years of age at the start) showed small but statistically significant changes over time suggestive of “pre-clinical signs” of dementia. When the data were sorted into 4 subgroups on the basis of age, a more detailed analysis revealed that the subgroup that was 50 years of age and older at the start showed changes in scores which were of a magnitude more clearly indicative of early dementia on the test measures. Deterioration in learning/memory functions began at a mean age of 54.2 years, followed later by deterioration in movement-related functions (praxis) at a mean age of 56.9 ...

Onset of Dyspraxia in Aging Persons with Down Syndrome: Longitudinal Studies.

The slow and insidious development of progressive dyspraxia is recognised as an early symptom of Alzheimer disease (AD) among aging persons from the general population. However, very little is known about the age of onset and development of these AD-associated movement-related disorders among aging persons with Down syndrome (DS). This report provides a brief description of the development and standardisation of a 62-item dyspraxia scale adapted for adults with Down syndrome. It also provides a progress report utilising the scale in a 3.5-year longitudinal study designed to test the hypothesis that older individuals with DS would provide evidence for the onset and progression of dyspraxia when compared with younger adults with DS. Persons with Down syndrome who were 40 years of age and older at the start showed statistically significant deterioration on some of the dyspraxia measures suggestive of “preclinical” signs of dementia of the Alzheimer type (DAT). An old group, with normal dyspraxia scores at a ...

The Relationship of Plasma Aβ Levels to Dementia in Aging Individuals With Down Syndrome

To study the relationship between plasma levels of amyloid β (Aβ) peptides and dementia in aging individuals with Down syndrome, we investigated the relationship among plasma Aβ, apolipoprotein E genotype and cognitive and clinical factors using baseline specimens form participants in an ongoing clinical trial in individuals with Down syndrome 50 years of age and older. Because of substantial skew in the distribution of peptide levels, analyses used log transformations of the data. The ratio of Aβ42 to Aβ40 was associated with the presence of dementia (P=0.003, df=196, F=9.37); this association persisted after adjustment for age, sex level of mental retardation, and apolipoprotein E genotype. Consistent with recent reports regarding the effect of presenilin mutations on peptide generation, our finding supports the theory that the ratio of Aβ42 to Aβ40 rather than absolute levels of the peptides is important to the pathophysiology of Alzheimers disease in genetically susceptible populations.

Relation between apolipoprotein E genotype, hepatitis B virus status, and thyroid status in a sample of older persons with Down syndrome

Dementia of the Alzheimer type (DAT) is common in older persons with Down syndrome (DS). There are three common alleles of the apolipoprotein E (ApoE) gene (Σ2, Σ3, and Σ4) resulting in three different isoforms (E2, E3, and E4) and six different genotypes (2,2; 2,3; 2,4; 3,3; 3,4; and 4,4). Σ4 is a risk factor for DAT whereas Σ2 appears prophylactic. As hepatitis B virus (HBV) infection and hypothyroidism also are common in DS, we evaluated associations between ApoE type, HBV status, and thyroid status in a sample of older persons with DS (n = 55; mean age, 44.3 ± 10.8 years) using chi‐squared analysis. Participants were classified as E2 (2,2 or 2,3), E3 (3,3), or E4 (3,4 or 4,4); positive for markers of HBV infection in the present or past (i.e., total HBcAb+ and/or HBsAg+ with or without infectivity, defined as HBV+) or negative for markers of HBV infection (defined as HBV−) and, currently receiving thyroid hormone supplement (defined as “hypothyroidism”) or having normal thyroid function. The majority of the HBV+ were currently HBcAb+ and HBsAb+, but not HBsAg+. In females, there was an ApoE allele effect on thyroid status (P ≤ 0.01), E2 being negatively (P ≤ 0.01) and E4 being positively (P ≤ 0.05) associated with “hypothyroidism”. There was no evidence for an ApoE allele effect on thyroid status in males. There was no evidence for an ApoE allele effect on HBV status, or for an HBV status effect on thyroid status. As thyroid status can affect cognitive function, ApoE allele effects in DAT may, in part, be thyroid effects.

The Multidimensional Observation Scale for Elderly Subjects (MOSES): studies in adults with intellectual disability

This report describes the results of five studies aimed at evaluating the usefulness, reliability, and validity of the Multidimensional Observation Scale for Elderly Subjects (MOSES) in the assessment of change in ageing persons with intellectual disability. Three hundred and thirty-six individuals with an average age of 49.8 years, including an equal number of men and women, were participants in one or more of the five studies. There were 220 participants with Down syndrome, 81 persons without Down syndrome with intellectual disability, and 35 persons from the general ageing population who were clinically diagnosed with Alzheimers disease using NINCD/ADRDA criteria. Persons with Down syndrome 40 years of age and older could be distinguished from their younger peers with Down syndrome by statistically significant poorer scores on the MOSES, with those 50 years of age and older showing the worst scores. Comparisons of adults with intellectual disability diagnosed with dementia of the Alzheimer type (DAT), using DSM-IV criteria, with or without Down syndrome, as well as comparisons of patients with clinically diagnosed depression, provided evidence that subtests of the MOSES were sensitive to DAT but less so to depression. These clinical groups also showed significantly poorer scores on the MOSES when compared with those of the normative sample. It was concluded that the MOSES is a behavioural observation scale that can provide useful information in clinical settings as well as in research.