The relationship between motor abilities and quality of life in children with severe multiple disabilities.

BACKGROUND: This study aimed to determine the relationship between motor abilities and quality of life in children with severe multiple disabilities. METHODS: In this cross-sectional study, motor abilities of 29 children (mean age 9.8 years; 45% girls) with severe multiple disabilities [IQ < 25; Gross Motor Function Motor Classification System level V] were measured with the MOtor eVAluation in Kids with Intellectual and Complex disabilities (Movakic) questionnaire (completed by the child's physical therapist). Quality of life was measured with the Quality of Life-Profound Multiple Disabilities (QoL-PMD) questionnaire (completed by the child's parents). RESULTS: A significantly moderate to high correlation was found between the total scores on the Movakic and the QoL-PMD (r = 0.40, P = 0.03), indicating that higher scores in motor abilities are associated with a higher level of quality of life. Furthermore, significantly moderate to high correlations were found between the total score on the Movakic and the dimension Physical Well-Being, Development and Activities of the Qol-PMD. In multiple linear regression models, all significant bivariate relationships between the Movakic total scores and QoL-PMD dimensions remained significant after controlling for the Gross Motor Function Motor Classification System level. CONCLUSIONS: In these children with severe multiple disabilities, motor abilities (as measured by Movakic) are moderately related to quality of life (as measured by the QoL-PMD).

A structured physical activity and fitness programme for older adults with intellectual disabilities: results of a cluster-randomised clinical trial.

BACKGROUND: The physical activity level of older adults with intellectual disabilities (ID) is extremely low, and their fitness levels are far beneath accepted norms for older people with normal intelligence and comparable with frail older people. A physical activity programme, including an education programme, was developed for older adults with ID using behaviour change techniques. The programme aimed at improving or maintaining adequate levels of physical activity (primary outcome measure) and motor fitness, cardio respiratory fitness, morphologic and metabolic fitness, activities of daily living, cognitive functioning and depressive symptoms (secondary outcome measures). METHOD: The programme's efficacy was evaluated in a cluster-randomised clinical trial among people aged 43 years and over with mild-moderate levels of ID. Five day-activity centres were randomised to the participation group. In these centres, 81 older adults participated in groups of 8 to 10 in the programme, three times a week during 8 months. The programme was executed by physical activity instructors and staff of day-activity centres. Five other day-activity centres were randomised to the control group; 70 older adults in these centres received care as usual. The generalised linear model with mixed effects was used to test the programme's effectiveness. RESULTS: Significant effects were found on physical activity, muscle strength, systolic and diastolic blood pressure, serum cholesterol level and cognitive functioning, in favour of the programme's participants. No significant improvements were found on balance, serum glucose, weight, waist circumference, walking speed, mobility, depression or instrumental activities of daily living. CONCLUSIONS: The physical activity and fitness programme has established small but significant effects in this sample, but generalising the findings to other settings is difficult due to significant participant dropout. Implementation of evidence-based physical activity programmes among older adults with ID is recommended. Further research is needed to investigate the effectiveness of physical activity on daily life functioning and the development on chronic diseases in the long run.

A 3-year follow-up study on cardiovascular disease and mortality in older people with intellectual disabilities.

BACKGROUND: With increasing longevity and a similar or increased prevalence of cardiovascular disease risk factors (as compared to the general population), people with intellectual disabilities (IDs) are at risk of developing cardiovascular disease. However, prospective studies on incidence and influencing factors of cardiovascular disease and mortality are lacking. METHODS: A three year follow-up study was undertaken to study the incidence and symptoms at presentation of myocardial accident, stroke and heart failure in older people with ID. Furthermore, the predictive value of cardiovascular disease risk factors on myocardial accident, stroke and heart failure and on all-cause mortality were studied. The baseline group consisted of the 1050 participants, aged 50 years and over, in the Dutch Healthy Ageing and Intellectual Disability (HA-ID) study. Baseline measurements were conducted between November 2008 and July 2010. Three years after baseline, medical files of 790 participants were studied. RESULTS: Cardiovascular disease (myocardial infarction, stroke and heart failure) occurred in 5.9% of the population during 3 year follow-up, and 32% of them died due to the condition. Incidence of myocardial infarction is 2.8 per 1000 personyears, for stroke 3.2 per 1000 personyears and for heart failure 12.5 per 1000 personyears. Incidence of these conditions is probably underestimated, due to atypical symptom presentation. The use of atypical antipsychotics and a history of heart failure were predictive for myocardial infarction. Heart failure was predicted by abdominal obesity, chronic kidney disease and a history of heart failure. A total of cardiovascular disease (myocardial infarction, stroke or heart failure) was predicted by abdominal obesity, a history of stroke and a history of heart failure. A low body-mass index, peripheral arterial disease, chronic kidney disease and inflammation were predictive for 3-year all-cause mortality. CONCLUSION: Incidence of cardiovascular disease in older people with ID is similar to that in the general population. A pro-active assessment and treatment of the presented cardiovascular disease risk factors may reduce cardiovascular disease and mortality in older people with ID.

Associations of symptoms of anxiety and depression with diabetes and cardiovascular risk factors in older people with intellectual disability.

BACKGROUND: Depression, anxiety, diabetes and cardiovascular risk factors are frequent health problems among older people with intellectual disability (ID). These conditions may be bidirectionally related. Depression and anxiety may have biological effects causing glucose intolerance, fat accumulation and also lifestyle changes causing metabolic syndrome. But also the effects of diabetes, metabolic syndrome and subsequent cardiovascular disease may affect mood and anxiety. This study investigated the association between depression, anxiety and diabetes and cardiovascular risk factors in older people with ID. METHODS: The healthy ageing in intellectual disability-study (HA-ID study) is a cross-sectional study among people aged 50 years and over with ID, receiving formal ID care. Screening instruments for symptoms of anxiety and depression were completed and physical examination and vena-puncture were performed to establish components of the metabolic syndrome, peripheral arterial disease and c-reactive protein. RESULTS: Of the 990 people who participated, 17% had symptoms of depression and 16% had symptoms of anxiety. Type I diabetes was present in 1%, type II diabetes in 13% of the study population. Metabolic syndrome, central obesity, hypercholesterolemia and hypertension were present in 45%, 48%, 23% and 53% respectively. In a multivariate logistic regression analysis a significant association was found between increased anxiety symptoms and diabetes only (OR 2.4, 95%CI 1.2-4.9). CONCLUSIONS: Increased anxiety symptoms and diabetes are related in older people with ID. This association may be bidirectional. No other associations of depression and anxiety symptoms with cardiovascular risk factors could be proven to be significant. Therefore, more research is needed to unravel the mechanisms of stress, mood disorders and cardiovascular disease in older people with ID. To provide comprehensive care for older people with ID, screening for diabetes and components of the metabolic syndrome in people with anxiety or mood disorders, and screening for symptoms of anxiety or depression in people with diabetes is warranted.

The prevalence of peripheral arterial disease in middle-aged people with intellectual disabilities.

Peripheral arterial disease (PAD) is a manifestation of atherosclerosis below the bifurcation of the abdominal aorta. PAD increases the risk of cardiovascular disease and associated mortality. Little is known about the prevalence of PAD in middle-aged persons with intellectual disabilities (ID). We determined the prevalence of PAD among people with ID aged 40-59 years. Independent associations between PAD and patient and care characteristics were explored. A multi-center cross-sectional observational study was conducted in four care providing agencies for people with ID in the Netherlands. We included 407 participants with mild to profound ID aged 40-59 years, receiving medical care from specialized ID physicians. The ankle-brachial index was used to diagnose PAD. The overall prevalence of PAD was 8.4% (95% CI=6.0-11.4%), with no significant differences between age groups 40-49 years (8.2%) and 50-59 years (8.5%). None of the participants had been diagnosed with PAD prior to this study and only one participant with PAD had PAD-related symptoms (1/34). Wheelchair dependence was independently associated with PAD (OR=5.43). Prevalence of PAD among people with ID is high, which is especially remarkable in age group 40-49 years. Physicians need to be aware of this high prevalence of PAD and the increased risk of cardiovascular disease in (young) people with ID.

Chronic kidney disease in older people with intellectual disability: results of the HA-ID study.

With increasing longevity and cardiovascular events, chronic kidney disease may also become a significant problem in older people with intellectual disability (ID). We studied prevalence and associations of chronic kidney disease as part of the Healthy Ageing and Intellectual Disability (HA-ID) study, a large Dutch cross-sectional study among people with ID aged 50 years and over, using creatinine and cystatin-C measurement in plasma. Glomerular filtration rate (GFR) was calculated using the Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations. Equations based on creatinine (as the MDRD equation) may underestimate kidney dysfunction in people with sarcopenia, because low muscle mass leads to a low creatinine production. Therefore, also prevalence of chronic kidney disease was studied in the sarcopenic group, using different GFR equations. Prevalence of chronic kidney disease, among 635 participants, was 15.3%, which equals prevalence in the general Dutch population. In the group of participants with sarcopenia (n=82), the CKD-EPI equation based on creatinine and cystatin-C gave a higher prevalence of chronic kidney disease than did the MDRD equation, but confidence intervals were very wide. Chronic kidney disease was associated with higher age, Down syndrome, obesity, hypercholesterolemia and hypothyroid disease. GFR should be measured in all older people with ID and polypharmacy, and in older people with ID and Down syndrome as part of the regular health checks. Moreover, if sarcopenia is present and information on GFR is required, this should not be measured based on creatinine only, but additional measures, such as cystatin-C, should be taken into account.

Does format matter for comprehension of a facial affective scale and a numeric scale for pain by adults with Down syndrome?

People with intellectual disabilities are at high risk for pain and have communication difficulties. Facial and numeric scales for self-report may aid pain identification. It was examined whether the comprehension of a facial affective scale and a numeric scale for pain in adults with Down syndrome (DS) varies with presentation format. Adults with DS were included (N=106, mild to severe ID, mean age 37 years), both with (N=57) and without (N=49) physical conditions that may cause pain or discomfort. The Facial Affect Scale (FAS) and a numeric rating scale (NRS) were compared. One subgroup of participants (N=50) had to choose the two items within each format to indicate 'least pain' and 'most pain'. The other subgroup of participants (N=56) had to order three faces of the FAS from 'least pain' to 'most pain', and to answer questions about the magnitude of numbers for the NRS. Comprehension percentages were compared between two subgroups. More participants understood the FAS than the NRS, irrespective of the presentation format. The comprehension percentage for the FAS did not differ between the least-most extremities format and the ordering/magnitude format. In contrast, comprehension percentages for the NRS differed significantly between the least-most extremities format (61%) and the ordering/magnitude format (32%). The inclusion of ordering and magnitude in a presentation format is essential to assess thorough comprehension of facial and numeric scales for self-reported pain. The use of this format does not influence the number of adults with DS who pass the comprehension test for the FAS, but reduces the number of adults with DS who pass the comprehension test for the NRS.

Peripheral arterial disease in older people with intellectual disability in The Netherlands using the ankle-brachial index: results of the HA-ID study.

Older people with an intellectual disability (ID) have been shown to have similar to increased cardiovascular risks as compared to the general population. Peripheral arterial disease (PAD), atherosclerosis distal from the aortic bifurcation, is associated with increased cardiovascular morbidity and mortality. The prevalence of PAD has not been investigated in this population. Therefore, the aim of the present study was to determine the prevalence of PAD in older people with ID in The Netherlands, the rate of prior diagnoses, and correlations with participant characteristics, and to compare the prevalence with PAD in the general Dutch population. 771 people aged 50 years and over participated in ankle-brachial index (ABI) measurement as part of a multi-centre cross-sectional study (HA-ID study). PAD was defined as an ABI<0.9. After excluding those, who met the exclusion criteria, 629 participants remained. PAD was present in 20.7% of the participants and 97% had not been diagnosed before. People with higher age, smokers and people who lived in central settings, walked with support and were more dependent in activities of daily living were more at risk of PAD. Prevalence of PAD is higher than in the general population (17.4% of 562 eligible participants with ID, as compared to 8.1% of 917 Dutch participants of the PANDORA study, a pan-European study into the prevalence of PAD) through all age groups. Because the high prevalence of PAD implies a serious health risk for older people with ID, we recommend that ankle-brachial index measurement is to be routinely performed as part of the cardiovascular risk management in this group.

Remote eye tracking assesses age dependence processing of coherent motion in typically-developing children.

The aim of this study was to quantify processing of different types of coherent motion in terms of ocular motor response times in a group of normally-developing children (age 0-12+ years old) using remote eye tracking. Motion coherence was applied in three different types of Random Dot Kinematograms (RDKs): vertical (RDK1) and diagonal (RDK2) motion and expansion (RDK3). Orienting eye movements were quantified using the Reaction Time to the first Fixation (RTF). The children were divided into two groups: the "youngest group" between 0-3+ years and the "oldest group" between 4-12+ years old. The results showed that RTF was significantly prolonged in the "youngest group" compared to the "oldest group" for each RDK. In the "oldest group", RTF was significantly affected by the type of RDK shown. The presented results suggest that, based on ocular motor responses, age-dependence of processing different types of coherent motion may be revealed.

Delayed visual orienting responses in children with developmental and/or intellectual disabilities.

BACKGROUND: Assessment of higher visual processing functions mostly requires active cooperation of participants, which is problematic in children with intellectual disabilities (ID). To circumvent this, we applied remote eye tracking to quantify (ab)normal visual orienting responses in children with ID in terms of reaction times to visual stimuli. METHODS: We presented visual stimuli (cartoon, coherent form, and coherent motion) to 127 children (2-14 years) with developmental and/or ID (risk group) and simultaneously measured their orienting ocular motor responses. Reaction times to fixation (RTF) in the risk group were compared with RTF values of an age-matched control group. RESULTS: Overall, in 72% of the children in the risk group, RTF values to cartoon were delayed, in 47% to form, and in 38% to motion. The presence of delayed reaction times was highest in the group of children >4 years with ID. CONCLUSION: Our data show that a majority of children with developmental and/or ID have delayed visual orienting responses. This suggests that this group has increased risk for higher visual processing dysfunctions. Future studies are planned to correlate abnormal orienting responses to type of brain damage and to dissociate the responses from ocular motor disorders.

Prevalence and incidence of myocardial infarction and cerebrovascular accident in ageing persons with intellectual disability.

BACKGROUND: Epidemiological information on age-related cardiovascular disease in people with intellectual disability (ID) is scarce and inconclusive. We compared prevalence and incidence of cerebrovascular accident and myocardial infarction over age 50 in a residential population with ID to that in a general practice population. METHOD: A retrospective descriptive study was conducted, based on medical records of 510 persons with ID and 823 general practice patients, aged 50 years and over. RESULTS: Lifetime prevalences after age 50 were similar in both populations: 5.7% (95% CI 4.0-8.1%) in persons with ID and 4.4% (95% CI 3.1-6.0%) in the general population (Pearson chi-square 1.17, P = 0.279). Incidence per gender was similar between cohorts (men P = 0.86, women P = 0.36). There was no difference in incidence rates between the ID and control groups [relative risk = 1.5 (95% CI 0.9-2.4)]. CONCLUSION: Prevalence and incidence of myocardial infarction and cerebrovascular accident in ageing persons with ID do not appear different from those in the general population. It has to be taken into account that underdiagnosis and selection bias towards a more disabled group may have lead to underestimation of age-related cardiovascular morbidity, and the higher age and underrepresentation of Down syndrome to overestimation.

Feasibility and reliability of the Mini Nutritional Assessment (MNA) in older adults with intellectual disabilities.

OBJECTIVE: Feasibility and reliability of the Mini Nutritional Assessment (MNA) in older adults with intellectual disabilities (ID). DESIGN: Instrument development. SETTING: Three care providers for people with ID. PARTICIPANTS: 48 persons aged 50 years and over with borderline to profound ID and their professional caregivers. MEASUREMENTS: The MNA was performed by means of interviews with participants (N = 12) and caregivers (N = 48) and physical assessments of participants (N = 47). Aspects of feasibility: completion of interview, difficulty of answering interview items, duration of interview and completion of physical assessment. Aspects of reliability: inter-observer reliability between caregivers and between participants and caregivers, test-retest reliability and internal consistency. For inter-observer and test-retest reliability, intraclass correlation coefficients (ICC) were calculated, and for internal consistency Chronbach's alpha. RESULTS: All participants and caregivers completed the interview part. For 7 out of 12 personally interviewed participants and none of the caregivers, at least 3 out of 15 questions were difficult to answer. Mean duration of the interview was 7 minutes in participants and 4 minutes in caregivers. Physical assessment was successfully performed in 40 participants (85.1%). In the remaining 7 participants (14.9%) missing values were retrieved from the medical records. ICCs (95% confidence interval) for test-retest and inter-observer reliability between caregivers were good, 0.85 (0.72 - 0.92) and 0.86 (0.74 - 0.92) respectively, but ICC for inter-observer reliability between caregivers and persons with ID was low, 0.03 (-0.51 - 0.59). Internal consistency was 0.61. CONCLUSION: The MNA is feasible and reliable for older people with ID. Interview data can be reliably obtained through caregivers, but not through people with ID.

Cardiovascular risk factors (diabetes, hypertension, hypercholesterolemia and metabolic syndrome) in older people with intellectual disability: results of the HA-ID study.

Hypertension, diabetes, hypercholesterolemia and the metabolic syndrome are important risk factors for cardiovascular disease (CVD). In older people with intellectual disability (ID), CVD is a substantial morbidity risk. The aims of the present study, which was part of the Healthy Ageing in Intellectual Disability (HA-ID) study, were (1) to determine the prevalence of CVD risk factors in older people with ID and to compare this with the prevalence in the same-aged general population, (2) to determine how many risk factors had not been previously diagnosed, and (3) to identify correlates of CVD risk factors (gender, age, level of ID, Down syndrome, independent living, activities of daily living, mobility, instrumental activities of daily living, physical activity, use of atypical antipsychotics, central obesity), using logistic regression analyses. In this cross-sectional study, 980 people with borderline to profound ID participated. Hypertension (53%), diabetes (14%) and metabolic syndrome (45%) were present similarly as in the general Dutch population. Hypercholesterolemia was present less often (23%). Fifty percent of the people with hypertension had not been previously diagnosed with this condition. Percentages for diabetes, hypercholesterolemia, and the metabolic syndrome were 45, 46 and 94 respectively. People who were more at risk for CVD risk factors were women, older people, people with obesity, people who lived more independently and people who were able to do groceries or prepare a meal independently. Policy on prevention, detection and treatment of CVD risk factors is urgently needed.

Factors related to impaired visual orienting behavior in children with intellectual disabilities.

It is generally assumed that children with intellectual disabilities (ID) have an increased risk of impaired visual information processing due to brain damage or brain development disorder. So far little evidence has been presented to support this assumption. Abnormal visual orienting behavior is a sensitive tool to evaluate impaired visual information processing. Therefore, the main objective of this study was to investigate possible correlations between the children's characteristics (age, gender, level of ID, mobility, gestational age, cerebral palsy, Down syndrome, visual acuity, strabismus, nystagmus, and epilepsy), and abnormal visual orienting behavior. We quantified data on visual orienting behavior, in terms of visual processing time and ocular motor fixations, in 88 children with ID aged 4-14 years. These visual parameters were combined with data collected from the children's medical records (predictors) and were put in a Pearson bivariate correlation analysis. A predictor was included for multiple regression analysis if the Pearson's correlation coefficient had a level of significance of p<0.05. As shown by multiple regression analysis, age, level of ID, and Down syndrome significantly affected visual processing time. Mobility, strabismus, and nystagmus significantly affected fixation quality. Using a systematic approach, we confirmed the hypothesis that children with ID have an increased risk of impaired visual information processing which is related to a low IQ.

Prevalence, associated factors and treatment of sleep problems in adults with intellectual disability: a systematic review.

In people with intellectual disability (ID), impaired sleep is common. Life expectancy has increased in this group, and it is known that in general population sleep deteriorates with aging. Therefore the aims of this systematic review were to examine how sleep problems are defined in research among adults and older people with ID, and to collect information on the prevalence, associated factors and treatment of sleep problems in this population. PubMed, EMBase, PsycINFO and Web of Science were searched for studies published between January 1990 and August 2011. All empirical studies covering sleep problems in adults with ID were included, and assessed on quality (level of evidence), using a slightly modified version of the SIGN-50 methodology checklist for cohort studies. Of 50 studies that were included for systematic review, one was of high quality, 14 were well conducted, 14 were well conducted but with a high risk of bias, and 21 were non-analytical. The reported estimated prevalence rates of sleep problems in adults with ID ranged from 8.5% to 34.1%. A prevalence of 9.2% was reported for significant sleep problems. Sleep problems were associated with the following factors: challenging behavior; respiratory disease; visual impairment; psychiatric conditions; and using psychotropic, antiepileptic and/or antidepressant medication. Little information was found on older people specifically. Two studies reported treatment effects on sleep problems in larger populations; their findings suggest that non-pharmaceutical interventions are beneficial. Research on the prevalence, associated factors and treatment of sleep problems in adults and older people with ID has mainly focused on subjectively derived data. The definitions used to describe a sleep problem are not uniform, and associations are mainly described as correlations. In order to give recommendations for clinical practice further research is needed, involving objective measurements and multivariate analysis.

Lumbar spine and total-body dual-energy X-ray absorptiometry in children with severe neurological impairment and intellectual disability: a pilot study of artefacts and disrupting factors.

BACKGROUND: Children with severe neurological impairment and intellectual disability (ID) are susceptible for developing low bone mineral density (BMD) and fractures. BMD is generally measured with dual-energy X-ray absorptiometry (DXA). OBJECTIVE: To describe the occurrence of factors that may influence the feasibility of DXA and the accuracy of DXA outcome in children with severe neurological impairment and ID. MATERIALS AND METHODS: Based on literature and expert opinion, a list of disrupting factors was developed. Occurrence of these factors was assessed in 27 children who underwent DXA measurement. RESULTS: Disrupting factors that occurred most frequently were movement during measurement (82%), aberrant body composition (67%), small length for age (56%) and scoliosis (37%). The number of disrupting factors per child was mean 5.3 (range 1-8). No correlation was found between DXA outcomes and the number of disrupting factors. CONCLUSION: Factors that may negatively influence the accuracy of DXA outcome are frequently present in children with severe neurological impairment and ID. No systematic deviation of DXA outcome in coherence with the amount of disrupting factors was found, but physicians should be aware of the possible influence of disrupting factors on the accuracy of DXA.

Overweight and obesity in older people with intellectual disability.

Overweight and obesity are major health problems associated with increased cardiovascular disease risk, which is not sufficiently studied in people with intellectual disability yet. The present study was part of the Healthy Ageing in Intellectual Disability (HA-ID) study. The aim of this study was to establish (1) the prevalence of overweight, obesity and body fat percentage in older people with intellectual disability (ID) through measurement of Body Mass Index (BMI), waist circumference, waist-to-hip ratio (WHR) and skin fold thickness, and compare this with prevalence of overweight and obesity in the general population, and (2) the association of overweight and obesity with participant and treatment characteristics (gender, age, level of ID, Down syndrome, autism, independent living, smoking, (instrumental) activities of daily living ((I)ADL), physical activity and use of atypical antipsychotic medication) using regression analyses. In this cross-sectional study 945 persons, aged 50 and over with borderline to profound ID, living in central settings, in community settings and independently were included. Overweight and obesity were highly prevalent, with more obesity (26%) than in the general Dutch older population (10%) as measured by BMI, and 46-48% obesity as measured by waist circumference and WHR respectively. Women, people with Down syndrome, higher age, less severe ID, autism, people who are able to eat independently, preparing meals and doing groceries independently, people with physical inactivity and use of atypical antipsychotics were significantly more at risk of being overweight or obese. This merits specific actions by policy makers and clinical practice to improve health outcomes.

Exploring the use of actigraphy to investigate sleep problems in older people with intellectual disability.

BACKGROUND: The aim of this study was to explore the use of actigraphy to investigate sleep problems in a convenience sample of clients of Dutch intellectual disability (ID) care providers. Based on data obtained in a large multi-centre study on healthy ageing in people with ID, research questions were: 'To what degree are actigraphic measurements successful in this population?' and 'What is the influence of different sensitivity settings of the Actiwatch Sleep Analysis software on the distribution of sleep variables in this group?' METHODS: Data were collected in a cross-sectional descriptive study design. We included 563 participants, aged 50 years or older, with borderline to profound ID. Sleep-wake data were measured continuously during 14 days and nights using the Actiwatch AW7. A complete measurement of at least 7 days and nights, including at least one weekend day, was considered successful. Objective variables of sleep were analysed using different sensitivity settings of the Actiwatch AW7 Sleep Analysis software. RESULTS: In 200 participants (35.5%), a successful measurement was obtained. Unsuccessful measurements were caused primarily by problems with wearing the device and incomplete information on bed time and get up time. Of 382 participants who started wearing the Actiwatch, 354 (92.3%) wore it for at least 7 days. Application of different sensitivity settings of the Sleep Analysis software resulted in clear differences of all sleep parameters. CONCLUSIONS: Further research is needed into the validity of objective sleep parameters, as measured with the Actiwatch, for screening and epidemiological research in older people with ID. It needs to be investigated which sensitivity setting of the Actiwatch gives most valid results in this specific group, whereas reference data on sleep parameters and cut-off values are to be obtained.

Physical conditions and challenging behaviour in people with intellectual disability: a systematic review.

BACKGROUND: Challenging behaviour is a major problem among people with intellectual disabilities. Physical factors may be an important cause. The aim of the present systematic review was to determine the physical conditions associated with challenging behaviour. METHODS: A literature search was conducted in PubMed and the Cochrane systematic review database for empirical studies published between 1990 and 2008. The quality of all the studies that met the inclusion criteria was assessed using the SIGN-50 methodology checklists. RESULTS: The search identified 45 studies, which looked at general medical conditions, motor impairment, epilepsy, sensory impairment, gastrointestinal disease, sleep disorders, dementia and others. There were four high-quality observational studies, seven well-conducted observational studies, 21 observational studies of low methodological quality and 13 non-analytical studies. There were significant and independent associations between challenging behaviours and urinary incontinence, pain related to cerebral palsy and chronic sleep problems, and between self-injurious behaviour and visual impairment. No association was found with hearing impairment, bowel incontinence, mobility impairment or epilepsy. Many other physical conditions were not addressed at all. CONCLUSION: Medical conditions can play a role in challenging behaviour, and this should be evaluated in the clinical setting. So far, the level of evidence is generally low, and longitudinal studies are completely lacking. We recommend a systematic approach to research examining the role of physical conditions in challenging behaviour, the ultimate aim being to establish a basis for the development of clinical guidelines.

Cerebral Visual Impairment: which perceptive visual dysfunctions can be expected in children with brain damage? A systematic review.

The current definition of Cerebral Visual Impairment (CVI) includes all visual dysfunctions caused by damage to, or malfunctioning of, the retrochiasmatic visual pathways in the absence of damage to the anterior visual pathways or any major ocular disease. CVI is diagnosed by exclusion and the existence of many different causes and symptoms make it an overall non-categorized group. To date, no discrimination is made within CVI based on types of perceptive visual dysfunctions. The aim of this review was to outline which perceptive visual dysfunctions are to be expected based on a number of etiologies of brain damage and brain development disorders with their onset in the pre-, peri- or postnatal period. For each period two etiologies were chosen as the main characteristic brain damage. For each etiology a main search was performed. The selection of the articles was based on the following criteria: age, etiology, imaging, central pathology and perceptive visual function test. The perceptive visual functions included for this review were object recognition, face recognition, visual memory, orientation, visual spatial perception, motion perception and simultaneous perception. Our search resulted in 11 key articles. A diversity of research history is performed for the selected etiologies and their relation to perceptive visual dysfunctions. Periventricular Leukomalacia (PVL) was most studied, whereas the main tested perceptive visual function was visual spatial perception. As a conclusion, the present status of research in the field of CVI does not allow to correlate between etiology, location and perceptive visual dysfunctions in children with brain damage or a brain development disorder. A limiting factor could be the small number of objective tests performed in children experiencing problems in visual processing. Based on recent insights in central visual information processing, we recommend an alternative approach for the definition of CVI that is based on functional visual processing, rather than anatomical landmarks. This could be of benefit in daily practice to diagnose CVI.