The need for assessment of sensory functioning in ageing people with mental handicap

ABSTRACT. Within the framework of a study on the ageing process of people with mental handicap in the Netherlands, information about visual and hearing impairments in 1583 people with mental handicap living in group homes or institutions was obtained from their physicians by means of a written questionnaire. Of the people with Down's syndrome (DS) who were older than 50 years of age, 46% had a visual impairment, whereas approximately 13% of subjects with other causes of mental handicap at the same age experienced similar visual impairment. Hearing loss in this age group was reported in 28% of people with DS, but only in 8% of subjects with other causes of mental handicap. The most common eye condition was cataracts, and the most frequent cause of hearing impairment was infection. In people with severe and profound mental handicap of all ages, sensory impairments were more frequent than in persons with mild or moderate mental handicap. Glasses or hearing aids were rarely used by people with severe or profound mental handicap. Assessment of visual and hearing impairments in people with mental handicap seemed clearly indicated, especially in those aged 50 years and older, in those with DS, and in those with severe or profound mental handicap.     

Failure to detect deaf-blindness in a population of people with intellectual disability

Background   Early identification of deaf-blindness is essential to ensure appropriate management. Previous studies indicate that deaf-blindness is often missed. We aim to discover the extent to which deaf-blindness in people with intellectual disability (ID) is undiagnosed.
Method   A survey was made of the 253 residents of an institute offering residential and occupational facilities for people with IDs. Data are included for the 224 individuals who were able to complete both auditory and visual assessments. Otoacoustic emissions were used to screen for hearing impairment; those who did not pass were assessed by behavioural audiometry. Visual acuity was assessed with one of the following: EH-Optotypes, LH-Optotypes, Teller Acuity Cards, Cardiff Acuity Cards or the Stycar Ball Vision Test.
Results   Prior to the study hearing impairment had been diagnosed in 12.5% of the 224 subjects, and visual impairment in 17%. Upon completion of the study these figures rose to 46% and 38.4% respectively. Deaf-blindness was diagnosed in 3.6% of the subjects before, and in 21.4% after, the study. Most (87.5%) of the deaf-blind individuals had profound ID.
Conclusion   Deaf-blindness is most often not identified either by standard medical screening or by care staff. Individuals with this disability, however, require provision of special kinds of care. Four categories of deaf-blindness are proposed, according to the severity of sensory impairment in each modality. The tests used in this study are non-invasive and are appropriate for individuals with ID and children. Early and periodic screening for visual and hearing impairment in individuals with ID is recommended.     

Does visual impairment lead to additional disability in adults with intellectual disabilities?

Background   This study addresses the question to what extent visual impairment leads to additional disability in adults with intellectual disabilities (ID).
Method   In a multi-centre cross-sectional study of 269 adults with mild to profound ID, social and behavioural functioning was assessed with observant-based questionnaires, prior to expert assessment of visual function. With linear regression analysis the percentage of variance, explained by levels of visual function, was calculated for the total population and per ID level.
Results   A total of 107/269 participants were visually impaired or blind (WHO criteria). On top of the decrease by ID visual impairment significantly decreased daily living skills, communication & language, recognition/communication. Visual impairment did not cause more self-absorbed and withdrawn behaviour or anxiety. Peculiar looking habits correlated with visual impairment and not with ID. In the groups with moderate and severe ID this effect seems stronger than in the group with profound ID.
Conclusion   Although ID alone impairs daily functioning, visual impairment diminishes the daily functioning even more. Timely detection and treatment or rehabilitation of visual impairment may positively influence daily functioning, language development, initiative and persistence, social skills, communication skills and insecure movement.     

The impact of visual impairment on the ability to perform activities of daily living for persons with severe/profound intellectual disability

BackgroundThe ability to perform activities of daily living (ADL) as a component of participation is one of the factors that contribute to quality of life. The ability to perform ADL for persons experiencing severe/profound intellectual disability (ID) may be reduced due to their cognitive and physical capacities. However, until recently, the impact of the significantly prevalent visual impairments on the performance of activities of daily living has not yet been revealed within this group.AimThe purpose of this prospective cross-sectional study was to investigate the impact of visual impairment on the performance of activities of daily living for persons with a severe/profound intellectual disability.MethodThe Barthel Index (BI) and Comfortable Walking Speed (CWS) were used to measure the ability of performing activities of daily living (ADL) in 240 persons with severe/profound ID and having Gross Motor Functioning Classification System (GMFCS) levels I, II or III; this included 120 persons with visual impairment. The impact of visual impairment on ADL was analyzed with linear regression.ResultsThe results of the study demonstrated that visual impairment slightly affects the ability of performing activities of daily living (BI) for persons experiencing a severe/profound intellectual disability. GMFCS Levels II or III, profound ID level, and visual impairment each have the effect of lowering BI scores.GMFCS Levels II or III, and profound ID level each have the effect of increasing CWS scores, which indicates a lower walking speed. A main effect of visual impairment is present on CWS, but our results do show a substantive interaction effect between GMFCS level III and visual impairment on Comfortable Walking Speed in persons with a severe/profound intellectual disability.ConclusionsVisual impairment has a slight effect on ability to perform ADL in persons experiencing severe/profound ID.     

Prevalence of hypertension in adults with intellectual disability in the Netherlands

Background   Literature on the prevalence of hypertension in people with intellectual disability (ID) is mostly based on file studies or on measurements limited to the age group below 50 years. We measured and calculated the prevalence of hypertension in adults with ID and studied the distribution of hypertension in relation to age, gender, diagnosis of Down's syndrome and level of ID.
Methods   In an observational cross-sectional study, standardized blood pressure measurements were obtained from 258 randomly selected adult clients of three Dutch care providers for people with ID. Hypertension was defined as a mean systolic blood pressure above 140 mm Hg on repeated measurements.
Results   The overall prevalence rate of hypertension was 17.4% (95% CI 12.28–22.46). This was comparable to the prevalence in the general Dutch population. No accurate blood pressure measurement could be performed in 28.4% of people with severe and profound ID owing to repetitive physical activity or resistance. Hypertension was significantly related to older age and absence of Down's syndrome; no correlation with gender or level of ID could be shown.
Recommendation   The risk factor hypertension should be detected and treated in the same manner as in the general population following national guidelines.     

Life expectancy of people with intellectual disability: a 35-year follow-up study

A 35‐year follow‐up study based on a nation‐wide population study of the life expectancy of people with intellectual disability (ID) was undertaken. The study population consisted of a total of 60969 person‐years. A prospective cohort study with mortality follow‐up for 35 years was used and the life expectancy of people with ID was calculated for different levels of intelligence. Proportional hazard models were used to assess the influence of level of intelligence and associated disorders on survival. People with mild ID did not have poorer life expectancy than the general population and subjects with mild ID did not have lower life expectancy in the first 3 decades of life. In cases with profound ID, the proportion of expected life lost was > 20% for almost all age groups. The female preponderance was manifested from the age of 60 years onwards, 25 years later than in the general population. Respectively, survival between sexes differed less. Epilepsy and/or hearing impairment increased the relative risk of death for all levels of ID. The prevalence of people with ID over 40 years was 0.4%. People with ID now live longer than previously expected, and the ageing of people with mild ID appears to be equal to that of the general population, posing new challenges to health care professionals.     

Preliminary evaluation of a scale to assess cognitive function in adults with Down's syndrome: the Prudhoe Cognitive Function Test

Background In the clinical diagnosis of dementia in Down's syndrome (DS), it may be difficult to distinguish between cognitive deterioration and the various degrees of pre‐existing intellectual disability (ID). Serial measurements of both cognitive function and behaviour are required. The aim of the present study was to evaluate the performance of non‐demented adults with DS on a subject‐directed instrument, the Prudhoe Cognitive Function Test (PCFT), preliminary to its serial use in a prospective study. Methods From 1985 to 1986, 85 non‐demented hospitalized adults with DS were interviewed using the PCFT. The Adaptive Behavior Scale (ABS) was administered to the carers. The subjects’ levels of ID (graded from mild through moderate, severe and profound to untestable) were based on their scores on the Stanford–Binet Intelligence Scale, as reported in the medical records, and the relationship between level of disability and performance on the PCFT and ABS, and their respective domains, was examined. Results Both scales produced a wide range of scores and the correlation between them was highly significant. Both scales correlated highly significantly with the degree of ID, but more subjects with high levels (i.e. profound to untestable) of disability obtained very low or zero scores on the PCFT and its domains than on the ABS. Conclusions The PCFT provides a reliable quantitative measure of cognitive function in subjects with DS, and could be a useful adjunct to the diagnosis of dementia in prospective studies. However, the almost uniformly low scores obtained by those with high levels of ID suggests that its power to detect cognitive decline will be limited to those who are less disabled, while the ABS may be more useful than the PCFT in detecting deterioration in people with profound ID.     

Sensory impairments, intellectual disability and psychiatry

The present review looks at: (1) prevalence studies of sensory impairments in people with intellectual disability (ID); (2) studies looking at psychological and psychiatric disorders in people with sensory impairments; and (3) studies that have examined the association of sensory impairments with autism. Research has indicated that sensory impairments are more common in people with ID. Psychiatric disorders are believed to be more common in children with visual impairment (VI) when associated with other handicaps. Some authors believe that hearing impairment (HI) can result in personality disorders. Studies have also shown a higher prevalence of psychiatric disorders in children with HI and a higher incidence of deaf people in psychiatric hospitals than in the general population. Psychiatric disorders in children with HI are particularly associated with low IQ and low communication ability, especially in those with multiple handicaps. There is little evidence for a higher incidence of schizophrenia in people with HI. Blind people demonstrate many autistic‐like features and there has been discussion in the literature as to their cause. Deaf people also demonstrate some similar features to those in autism, but an association with autism has not been conclusively made. Deaf‐blind people commonly demonstrate problem behaviour (e.g. self‐injury). Usher syndrome, which is the most common cause of deaf‐blindness, is associated with psychiatric disorders, particularly psychosis. The need for assessment of sensory functioning in people with ID, the difficulties inherent in this and the need for specialist services is stressed.     

Medical aspects of ageing in a population with intellectual disability: II. Hearing impairment

Hearing function of an institutionalized population with intellectual disability, consisting of 70 subjects with a mean age of 70.1 (range 60–92) years at initial evaluation, was assessed during a 10-year longitudinal study. One subject had Down's syndrome and could not be assessed as a result of dementia. The total prevalence of mild to severe hearing loss (33.3% in the 60–70 age group and 70.4% in those over age 70) was comparable to reported data from an ageing populadon without intellectual disability in the United Kingdom (37%, respectively 60%), However, the proportion of moderate to severe losses might be higher (16.7%vs. 7% in the 60–70 age group and 33.3%vs. 18% in the older age group). Excess impairment was caused by severe congenital and childhood hearing impairment on one hand, and by conductive losses, probably caused by unrecognized chronic middle ear infections, superposed upon presbyacusis, on the other. Impacted ear wax was also a major problem. The incidence of new cases with hearing loss during follow-up was 50%, After individual habituation training hearing aids were used without difiFiculdes by 20 out of 24 subjects. The importance of acdve screening and treatment of middle ear infections and hearing impairment from a young age     

Prevalence, aetiology and comorbidity of severe and profound intellectual disability in Finland

Background The aim of the present study was to describe the aetiology, associated impairments and prevalence of severe and profound intellectual disability (SPID) in Finland. Methods The number of people with SPID in the catchment area of the Pääjärvi Centre for the Mentally Retarded, Lammi, Finland, (total population = 341 227) was calculated from the client register of this centre. Aetiological factors and background diagnoses for all subjects with SPID were analysed retrospectively. Results The number of people with SPID was 461, giving a prevalence of 0.13%. The aetiology of their SPID was genetic or congenital in 235 (50.9%) individuals, acquired in 89 (19.3%), genetic and/or acquired in 84 (18.3%), and unknown in 53 (11.5%) subjects. Out of the 53 individuals with an SPID of unknown origin, 48 (90.6%) had an associated impairment; the remaining five were the only members of the study group showing normal growth, and having neither dysmorphic features, physical abnormalities nor family members with ID. Out of the 461 subjects, 422 (91.5%) had between one and six associated impairments (total = 954), and the remaining 39 (8.5%) had SPID as their only impairment. Uncomplicated SPID was mainly of genetic or congenital origin, whereas all subjects with acquired encephalopathy had multiple disabilities. Speech defects, epilepsy and cerebral palsy were the most common associated impairments. Conclusions Severe and profound ID almost always occurs concomitantly with other severe neurological or psychiatric impairments. The proportion of people with SPID described in the present study is similar to that found in Finland in 1966. The aetiology of SPID in the vast majority of cases is biopathological.     

Ageing in adults with Down's syndrome in institutionally based and community-based residences

Seventy-one subjects with Down's syndrome (DS), between the ages of 29 and 68 years, and 46 matched controls (without DS) were examined for intelligence, memory (short- and long-term memory, and spatial and temporal orientation), communication (receptive, expressive and written language) and daily living skills (personal, domestic and community daily living skills). All subjects were screened on hearing and visual functions, thyroid functions; depression and dementia. DS-subjects and controls were matched on chronological age, mental age, living conditions and male/female ratio. Comparisons were made between five subgroups (I) non-demented institutionalized subjects with DS (DSI-group; n=35); (2) non-demented institutionalized controls without DS (Ci-group; n=22); (3) demented institutionalized subjects with DS (n= 10); (4) non-demented subjects with DS living in group homes (DSg; n=26); and (5) non-demented controls without DS living in group homes (Cg; n=24). Institutionalized and non-institutionalized subjects, as well as demented and non-demented subjects differed significantly on all functions measured. Multiple regression analysis was performed to examine the influence of age and sensory deficits on adaptive and cognitive functioning. In DSg subjects, significant associations were found between age and mental age, and between age and performances on written language. In (non-demented) DSi subjects, significant relations were found between age and memory functions observed in daily circumstances. Moreover, in the (non-demented) DSi elderly, visual impairment was significantly related to depressed performance on daily living skills. No age effects were seen in control subjects. Infirmities of old age like dementia and sensory deficits were far more common in people with DS than in controls. Psychiatric and diagnostic aspects of clinical depression and dementia were emphasized in particular.     

Combined hearing and visual impairment and depression in a population aged 75 years and older

BACKGROUND: Depression is associated with both visual and hearing impairment. Little is known about the relationship between combined hearing and visual impairment and mood in this age group. The aim of this population-based study was to investigate the association between functional sensory impairment, especially combined sensory impairment and depressive symptoms and depression diagnosed according to the DSM-IV criteria. METHOD: The study group consisted of 470 adults, population-based sample, aged 75 years or older. We used the Snellen eye charts with E-letters and reading charts to evaluate the functional visual acuity. The ability to conduct a face-to-face conversation, the hearing aid use and the self-reported hearing problems were used to assess the functional hearing acuity. Depression was identified with two different methods. A geriatrician interviewed the subjects and the DSM-IV checklist was used to determine whether they met the criteria for major depression. The Zung Depression Status Inventory (DSI) was used to identify depressive symptoms. The cut off points of 40/80 and 48/80 in the DSI-score was used. RESULTS: Seventy-two persons (15%) of the study population had depression diagnosed according to the DSM-IV criteria. Twelve per cent of subjects in the Functional Hearing Impairment (FHI) group, twenty per cent in the Functional Visual Impairment (FVI) group, eighteen per cent in the Combined Sensory Impairment (CSI) group and fifteen per cent in the Adequate Sensory Function (ASF) group suffered major depression. The differences between these groups were insignificant. The occurrence rates of the DSI score equal or over 40 points was 50% in the FHI group, 53% in the FVI group, 70% in the CSI group and 45% in the ASF group. The difference between the ASF group and sensory impairment group including FHI, FVI and CSI groups was statistically significant (p = 0.03). CONCLUSIONS: Depressive symptoms, but not major depression, were common if elderly persons had combined sensory impairment.     

Prevalence and incidence of health problems in people with intellectual disability

The objective of this study was to determine the prevalence and incidence of the most frequent chronic health problems in relation to age in people with intellectual disabilities living in residential facilities in the Netherlands. A prospective cohort study was done with four data collections, each with an interval of one year. Data were collected by means of questionnaires which were completed by each person's physician. Striking results included the reported high prevalence and incidence of visual and hearing impairment, which was even more pronounced in people with Down's syndrome than in people with intellectual disability resulting from other causes. Gastrointestinal problems also appeared to have high incidence rates. Dementia was frequently reported in people with Down's syndrome aged 40 years and older. The results reflect the need for a more predictive policy which can anticipate health problems in people with intellectual disability.     

Visual impairments in people with severe and profound multiple disabilities: an inventory of visual functioning

Background The prevalence of visual impairments in people with severe and profound multiple disabilities (SPMD) is the subject of considerable debate and is difficult to assess. Methods In a typical Dutch care organization, all clients with SPMD (n = 76) participated in the study and specific instruments adapted to these clients (requiring a minimum of cooperation) were used to measure visual acuity, the visual field, binocular vision, contrast sensitivity, refractive errors and visual functioning behaviour. Results We found an unexpected 92% of clients with SPMD to have visual impairments. Previously, only 30% were known to have visual problems. None of the persons observed had normal visual acuity. Subnormal visual acuity was the best result. The severity of the visual impairment was related to the severity of the intellectual disability. In addition to the problem of acuity, impairments in the visual field, impaired contrast sensibility and impaired binocular functioning were found, as well as impaired visual attention, fixation and following. In 22% of the _clients observed, refractive errors were found and glasses were advised. Conclusions Consequences for caregiving and for modifications of the environment were discussed.     

Diagnosis of sensory impairment in people with intellectual disability in general practice

The present authors have participated in the development of a Dutch consensus on the early detection, diagnosis and treatment of hearing and visual impairment in children and adults with intellectual disability. They argue that the early detection of sensory impairment in babies and children with intellectual disability should primarily be a responsibility of paediatricians and youth health physicians. General practitioners should be aware of the necessity of screening and should check whether this has been done when children visit the surgery. It is stressed that the general practitioner should play a more active role in the detection of age-related sensory loss in older adults with intellectual disability, and the assessment of younger adults whose sensory functions have never or incompletely been evaluated. Annual sensory screening is certainly not necessary, but annual otoscopy to detect impacted earwax or unidentified middle ear infection, as well as checks of the proper use of glasses and hearing aids, are suggested. Most adults with mild or moderate intellectual disability can be assessed with methods that are normally used by general practitioners. Uncooperative people should be referred for screening with specialized methods. A low-threshold referral system (e.g. via district expert teams) has been outlined.     

Multimorbidity in older adults with intellectual disabilities

Multimorbidity may be related to the supposed early aging of people with intellectual disabilities (ID). This group may suffer more often from multimorbidity, because of ID-related physical health conditions, unhealthy lifestyle and metabolic effects of antipsychotic drug use. Multimorbidity has been defined as two or more chronic conditions. Data on chronic conditions have been collected through physical assessment, questionnaires, and medical files. Prevalence, associated factors and clusters of multimorbidity have been studied in 1047 older adults (≥50 years) with ID. Multimorbidity was prevalent in 79.8% and associated with age and severe/profound ID. Four or more conditions were prevalent in 46.8% and associated with age, severe/profound ID and Down syndrome. Factor analyses did not reveal a model for disease-clusters with good fit. Multimorbidity is highly prevalent in older adults with ID. Multimorbidity should receive more attention in research and clinical practice for targeted pro-active prevention and treatment.     

Factors influencing the mammography utilization among Taiwanese women with intellectual disabilities,a nationwide population-based study

Women with intellectual disabilities (ID) have cognitive impairment and communication difficulties; for both caregivers and clinical personnel, discovering the early symptoms of breast cancer among women with ID is challenging. The mammography utilization rate of women with ID was significantly lower than that of women in the general population. This study employed a 2008 database of people with disabilities in Taiwan as a research target and analyzed the mammography utilization rate of women with ID aged 50–69 years. In addition, relevant factors influencing mammography utilization among women with ID were also investigated. A total of 4370 participants were recruited and the majority were illiterate or had elementary-level educations (82.27%). The majority of the participants had ID that was more severe than mild (83.80%). The mammography utilization rate of women with ID was 4.32%, which was significantly lower than that of women in the general population (12%). The mammography utilization rate among women with ID who were married, had higher education levels, and had been diagnosed with cancer, diabetes, or mild ID was significantly higher. However, the mammography utilization rate among women with ID, who had elementary-level educations or were illiterate, was only 4.03%. The utilization rate among women with profound ID was only 2.65%. Women with ID who had undergone pap smears or had utilized adult preventive health services demonstrated a significantly higher mammography utilization rate. This study identified that education level, a diagnosis of diabetes, and the application of pap smears or adult preventive health services were primary factors that influenced the mammography utilization rate among women with ID. This study also observed that in Taiwan, the mammography utilization rate of women with ID was lower than that of pap smears and adult preventive health services, and was only half of that of people with disabilities. An unequal situation existed in regard to the acceptance of breast cancer screening among women with ID, and a different form of strategic planning must be adopted in public health policy. Because ID differs from other disabilities and most women with ID are illiterate, tailored courses are required to train primary caregivers and clinical personnel in providing knowledge and services. The objectives are to diagnose breast cancer at an early stage to decrease the risk of mortality and ensure their rights to health.     

Incidence of dementia in older adults with intellectual disabilities

Dementia may be more common in older adults with intellectual disability (ID) than in the general population. The increased risk for Alzheimer's disease in people with Down syndrome (DS) is well established, but much less is known about dementia in adults with ID who do not have DS. We estimated incidence rates from a longitudinal study of dementia in older adults with ID without DS and compared them to general population rates. 222 participants with ID without DS aged 60 years and older were followed up an average of 2.9 years later to identify those who had declined in functional or cognitive abilities. Those who screened positive had a comprehensive assessment for dementia, diagnosed using ICD 10 and DSM IV criteria. 134 participants who did not have dementia at initial assessment were alive and interviewed at follow up; 21 (15.7%) were diagnosed with dementia. Overall incidence rate for those aged ≥60 was 54.6/1000 person years (95% CI 34.1–82.3). The highest incidence rate (97.8/1000 person years) was in the age group 70–74. Standardised incidence ratio for those aged ≥65 was 4.98 (95% CI 1.62–11.67). Incidence of dementia in older people with intellectual disabilities are up to five times higher than older adults in the general population. Screening may be useful in this population given the high incident rates, particularly as more effective treatments become available. Studies to explore the underlying aetiological factors for dementia associated with intellectual disability could help to identify novel protective and risk factors.