A 12-week exercise programme has a positive effect on everyday executive function in young people with Down syndrome: a pilot non-randomised controlled trial

BACKGROUND

Exercise has the potential to reduce cognitive decline in people with Down syndrome by maximising their cognitive function. The aim of the study was to determine the effect of regular exercise on cognitive functioning in young people with Down syndrome.

METHOD

People with Down syndrome were eligible if aged between 13 and 35 years and enrolled to participate in an exercise programme (called FitSkills). The intervention was a 12-week community-based exercise programme completed with a student mentor. Outcomes were assessed before (week 0) and immediately after (week 13) the intervention. Executive functioning (planning, response inhibition, attention shifting) was assessed using Tower of London, Sustained Attention to Response Task, CANTAB Intra-extra Dimensional Set Shift Test, Cognitive Scale for Down Syndrome, and Behaviour Rating Inventory of Executive Function (BRIEF). Working memory was assessed using the CANTAB Paired Associates Learning task, and information processing speed was assessed using the Motor Screening Task. Outcomes were analysed using ANCOVA with the baseline measure as the covariate.

RESULTS

Twenty participants (9 women; mean age 23.6 ± 6.6 years) enrolled. Between-group differences, in favour of the experimental group, were found for the global executive composite score of the BRIEF (mean difference -4.77 units, 95% CI -9.30 to -0.25). There were no between group differences for any other outcome measured.

CONCLUSION

Participation in a 12-week exercise programme was effective in improving everyday executive functions in young people with Down syndrome. These preliminary findings need to be confirmed in future randomised controlled trials of community-based exercise with larger sample sizes.

Diagnosis of Attention Deficit Hyperactivity Disorder in Intellectual Disability: Diagnostic and Statistical Manual of Mental Disorder V versus clinical impression

BACKGROUND

Diagnosing Attention Deficit Hyperactivity Disorder (ADHD) in people with intellectual disability (ID) remains challenging. The Diagnostic and Statistical Manual of Mental Disorder V (DSM V) classification system is often used to diagnose ADHD in the general population; however, the presence of ID and other associated conditions such as autism and communication difficulties can make it difficult to apply the DSM V criteria in people with ID. Therefore, diagnosing ADHD in people with ID is often made using clinical judgement and/or the application of diagnostic criteria. There are no studies comparing the diagnostic accuracy of clinical judgement and the use of DSM V criteria in people with ID and ADHD.

METHOD

The aims of the study were to compare the accuracy of the diagnosis of ADHD in people with ID according to the DSM V criteria versus clinical judgement and to determine which criteria are more reliable. A questionnaire was developed using five fictional case scenarios of people with ID. Questionnaires were presented to practising psychiatrists chosen as a convenience sample in the United Kingdom over a period of 12 months. Case scenarios were developed and agreed to be positive or negative for ADHD by the study authors prior to rating by clinicians. The clinicians were asked to read the scenarios and to make a judgement on the cases regarding the symptoms of ADHD. They were then presented with the 18 DSM V criteria of ADHD and asked to select the criteria they considered were present in each scenario. Sensitivity, specificity, likelihood ratios and predictive values for both the DSM V criteria and clinical opinions were calculated for correctly identifying the exemplar cases.

RESULTS

The data showed strong sensitivity [0.82 95% confidence interval (CI) 0.74-0.89] and high specificity (1.00 95% CI 0.95-1.00) for the raters' clinical opinion. In contrast, the DSM V criteria alone, as assessed by the raters, did not reliably provide ADHD diagnoses, with a sensitivity of only 0.23 (95% CI 0.15-0.31). This difference in sensitivity between the two was statistically significant at P < 0.001.

CONCLUSION

The study results suggest that clinical opinion is the 'gold standard' at present in diagnosing ADHD in adults with ID in the absence of a validated diagnostic tool in this group. Further studies are needed to understand how symptoms of ADHD can be presented differently in people with ID. DSM V criteria for ADHD may need to be adapted according to the severity of ID and other neurodevelopmental disorders.

Kondo effect and enhanced magnetic properties in gadolinium functionalized carbon nanotube supramolecular complex

We report on the enhancement of magnetic properties of multiwalled carbon nanotubes (MWNTs) functionalized with a gadolinium based supramolecular complex. By employing a newly developed synthesis technique we find that the functionalization method of the nanocomposite enhances the strength of magnetic interaction leading to a large effective moment of 15.79 µ_B and non-superparamagnetic behaviour unlike what has been previously reported. Saturating resistance at low temperatures is fitted with the numerical renormalization group formula verifying the Kondo effect for magnetic impurities on a metallic electron system. Magnetoresistance shows devices fabricated from aligned gadolinium functionalized MWNTs (Gd-Fctn-MWNTs) exhibit spin-valve switching behaviour of up to 8%. This study highlights the possibility of enhancing magnetic interactions in carbon systems through chemical modification, moreover we demonstrate the rich physics that might be useful for developing spin based quantum computing elements based on one-dimensional (1D) channels.

The relationship between sound-shape matching and cognitive ability in adults with Down syndrome

Down syndrome (DS), the most common genetic cause of intellectual disability, is characterised by a pattern of cognitive deficits hypothesised as relating to later developing neural systems. Multisensory integration (MSI) has been shown to benefit cognitive performance on numerous tasks in the typically developing population and is implicated in the early development of various cognitive processes. Given these developmental links of both MSI and DS it is important to determine the relationship between MSI and DS. This study aimed to characterise sound-shape matching performance in young adults with DS as an indicator of MSI (correct response rate around 90% in typically developing individuals). We further investigated the relationship between task performance and estimated cognitive ability (verbal and non-verbal) in addition to everyday adaptive behavior skills. Those answering correctly (72.5%) scored significantly higher across cognitive and adaptive behavior measures compared to those answering incorrectly. Furthermore, 57.1% of individuals with estimated cognitive ability scores below the median value answered correctly compared to 89.5% of individuals scoring above the median, with similar values found for adaptive behavior skills (57.9% vs 94.4%). This preliminary finding suggests sound-shape matching deficits are relatively common in DS but may be restricted to individuals of lower ability as opposed to being a general characteristic of DS. Further studies investigating aspects of MSI across a range of modalities are necessary to fully characterise the nature of MSI in DS and to explore underlying neural correlates and mechanisms.

Ethnicity and self-reported experiences of stigma in adults with intellectual disability in Cape Town, South Africa

BACKGROUND

Studies have shown that individuals with intellectual disability (ID) are aware of stigma and are able to describe experiences of being treated negatively. However, there have been no cross-cultural studies examining whether self-reported experiences of stigma vary between ethnic groups.

METHOD

Participants with mild and moderate ID were recruited from a number of different settings in Cape Town, South Africa. Self-reported experiences of stigma in three ethnic groups were measured using the South African version of the Perceived Stigma of Intellectual Disability tool, developed by the authors. One-way anova was used to test whether there were differences in the total stigma score between the ethnic groups. Regression analysis was performed to identify factors associated with stigma.

RESULTS

A total of 191 participants agreed to take part; 53 were Black, 70 were of mixed ethnicity and 68 were Caucasian. There were no differences in the levels of stigma reported by the three groups but the Black African ethnic group were more likely to report being physically attacked and being stared at, but were also more likely to report that they thought they were 'the same as other people'. There was an interaction effect between ethnicity and level of ID, with participants with mild ID from the Black African group reporting higher levels of stigma compared with those with moderate ID. Younger age was the only factor that was associated with stigma but there was a trend towards ethnicity, additional disability and socio-economic status being related to stigma.

CONCLUSION

Interventions should target the Black African community in South Africa and should include the reduction of both public stigma and self-reported stigma.

Estimated verbal IQ and the odds of problem gambling: a population-based study

BACKGROUND

The neurocognitive deficits and other correlates of problem gambling are also observable in individuals with lower cognitive abilities, suggesting that a low IQ may be a determinant of problem gambling. There has been very little research into this possibility. This study aimed to investigate the characteristics associated with problem gambling in a large population-based study in England, with a particular focus on IQ.

METHOD

The Adult Psychiatric Morbidity Survey (APMS) 2007 comprised detailed interviews with 7403 individuals living in private households in England. Problem gambling was ascertained using a questionnaire based on DSM-IV criteria. Verbal IQ was estimated using the National Adult Reading Test (NART). Confounders included socio-economic and demographic factors, common mental disorders, impulsivity, smoking, and hazardous drug and alcohol use.

RESULTS

More than two-thirds of the population reported engaging in some form of gambling in the previous year, but problem gambling was rare [prevalence 0.7%, 95% confidence interval (CI) 0.5-1.0]. The odds of problem gambling doubled with each standard deviation drop in estimated verbal IQ [adjusted odds ratio (OR) 2.1, 95% CI 1.3-3.4, p = 0.003], after adjusting for other characteristics associated with problem gambling including age, sex, socio-economic factors, drug and alcohol dependence, smoking, impulsivity and common mental disorders. There was no strong relationship observed between IQ and non-problem gambling.

CONCLUSIONS

People with lower IQs may be at a higher risk of problem gambling. Further work is required to replicate and study the mechanisms behind these findings, and may aid the understanding of problem gambling and inform preventative measures and interventions.

The relationship between happiness and intelligent quotient: the contribution of socio-economic and clinical factors

BACKGROUND

Happiness and higher intelligent quotient (IQ) are independently related to positive health outcomes. However, there are inconsistent reports about the relationship between IQ and happiness. The aim was to examine the association between IQ and happiness and whether it is mediated by social and clinical factors. Method The authors analysed data from the 2007 Adult Psychiatric Morbidity Survey in England. The participants were adults aged 16 years or over, living in private households in 2007. Data from 6870 participants were included in the study. Happiness was measured using a validated question on a three-point scale. Verbal IQ was estimated using the National Adult Reading Test and both categorical and continuous IQ was analysed.

RESULTS

Happiness is significantly associated with IQ. Those in the lowest IQ range (70-99) reported the lowest levels of happiness compared with the highest IQ group (120-129). Mediation analysis using the continuous IQ variable found dependency in activities of daily living, income, health and neurotic symptoms were strong mediators of the relationship, as they reduced the association between happiness and IQ by 50%.

CONCLUSIONS

Those with lower IQ are less happy than those with higher IQ. Interventions that target modifiable variables such as income (e.g. through enhancing education and employment opportunities) and neurotic symptoms (e.g. through better detection of mental health problems) may improve levels of happiness in the lower IQ groups.

The development of manualised cognitive behaviour treatment for adults with mild intellectual disability and common mental disorders

People with intellectual disability are at a greater risk of developing common mental disorders. In the United Kingdom, the National Institute for Health and Clinical Excellence guidelines recommend cognitive behavioural therapy (CBT) as the treatment of choice for such problems. Even though there is growing evidence that people with mild intellectual disability can benefit from CBT, there are no manuals to assist in the delivery of the treatment. Previously published material from journals and books describing both CBT in people with intellectual disability and the general population was reviewed to create the first draft. Further consultations with professionals and service users with intellectual disability on the content, accessibility and language that was used in the manual were carried out. Specific materials were developed for use in the therapy sessions and for homework. The manual, written for trained therapists, provides generic information about communication and thinking styles in people with mild intellectual disability and describes in detail how to conduct each session. It contains also contains the materials and a leaflet to help carers support the treatment. Manualised treatments are helpful in maintaining a consistent approach to treatment and may be more beneficial for hard to reach population groups.

The relationship of dementia prevalence in older adults with intellectual disability (ID) to age and severity of ID

BACKGROUND

Previous research has shown that adults with intellectual disability (ID) may be more at risk of developing dementia in old age than expected. However, the effect of age and ID severity on dementia prevalence rates has never been reported. We investigated the predictions that older adults with ID should have high prevalence rates of dementia that differ between ID severity groups and that the age-associated risk should be shifted to a younger age relative to the general population.

METHOD

A two-staged epidemiological survey of 281 adults with ID without Down syndrome (DS) aged 60 years; participants who screened positive with a memory task, informant-reported change in function or with the Dementia Questionnaire for Persons with Mental Retardation (DMR) underwent a detailed assessment. Diagnoses were made by psychiatrists according to international criteria. Prevalence rates were compared with UK prevalence and European consensus rates using standardized morbidity ratios (SMRs).

RESULTS

Dementia was more common in this population (prevalence of 18.3%, SMR 2.77 in those aged 65 years). Prevalence rates did not differ between mild, moderate and severe ID groups. Age was a strong risk factor and was not influenced by sex or ID severity. As predicted, SMRs were higher for younger age groups compared to older age groups, indicating a relative shift in age-associated risk.

CONCLUSIONS

Criteria-defined dementia is 2-3 times more common in the ID population, with a shift in risk to younger age groups compared to the general population.

What to tell and how to tell: a qualitative study of information sharing in research for adults with intellectual disability

OBJECTIVES

To explore opinions and attitudes regarding the current information-giving practices in research involving adults with intellectual disabilities.

DESIGN

Qualitative focus group study with a purposive sample.

SETTING

An intellectual disabilities service within the NHS PARTICIPANTS: A sample of 26 individuals including adults with mild intellectual disability, carers, clinicians, care managers and the charitable sector.

RESULTS

Three main themes were identified: process, format, and content. There was agreement that there is a need for improvement in the process and quality of information giving. With regard to the content of information, there was little discrepancy between the study findings and existing guidance.

CONCLUSIONS

Information should be presented in different formats and prepared with input from appropriate professions. Additionally the roles of peers, carers and other professionals in the process of information giving should be considered.

Psychiatric morbidity and social functioning among adults with borderline intelligence living in private households

BACKGROUND

Approximately one-eighth of the population will have DSM-IV borderline intelligence. Various mental disorders and social disability are associated with it.

METHOD

The paper uses data (secondary analysis) from a UK-wide cross-sectional survey of 8450 adults living in private households. Data were collected on psychiatric disorders, intellectual level, social functioning and service use.

RESULTS

In total, 12.3% of the sample had borderline intelligence. The prevalence of psychotic disorder was not significantly increased, but the group showed significant social disadvantage and increased rates of neurotic disorders, substance misuse and personality disorders when compared with their counterparts of normal intelligence. The borderline group was more likely to receive psychiatric medication, but not talking therapies. They appear to use significantly more services, including emergency services.

CONCLUSION

Adults with borderline intelligence are more likely to suffer from treatable mental disorders and an excess of substance misuse. Services should be aware of hidden morbidity in this group.

Prevalence of dementia in intellectual disability using different diagnostic criteria

BACKGROUND

Diagnosis of dementia is complex in adults with intellectual disability owing to their pre-existing deficits and different presentation.

AIMS

To describe the clinical features and prevalence of dementia and its subtypes, and to compare the concurrent validity of dementia criteria in older adults with intellectual disability.

METHOD

The Becoming Older with Learning Disability (BOLD) memory study is a two-stage epidemiological survey of adults with intellectual disability without Down syndrome aged 60 years and older, with comprehensive assessment of people who screen positive. Dementia was diagnosed according to ICD-10, DSM-IV and DC-LD criteria.

RESULTS

The DSM-IV dementia criteria were more inclusive. Diagnosis using ICD-10 excluded people with even moderate dementia. Clinical subtypes of dementia can be recognised in adults with intellectual disability. Alzheimer's dementia was the most common, with a prevalence of 8.6% (95% CI 5.2-13.0), almost three times greater than expected.

CONCLUSIONS

Dementia is common in older adults with intellectual disability, but prevalence differs according to the diagnostic criteria used. This has implications for clinical practice.

Social outcomes in adulthood of children with intellectual impairment: evidence from a birth cohort

BACKGROUND

Social Policy for people with intellectual disabilities (ID) continues to evolve, but little is known about the lives to which such policies are applied. We aimed to use a prospective follow-up of a British birth cohort to identify children with mild and more severe intellectual impairment, and compare a range of social outcomes in adulthood with people in the rest of the cohort.

METHOD

We used data from the MRC National Survey for Health and Development. Intellectual impairment was identified by intelligence tests and educational history. Adult outcome measures included employment and social class, education, marriage and children, home ownership, social networks and community use.

RESULTS

We identified 111 people with mild intellectual impairment (2.7%) and 23 with severe intellectual impairment (0.6%) at age 15/16. By the age of 43, there were 52 people remaining in the mild impairment group and 14 in the severe impairment group. In adulthood those with intellectual impairment enjoyed contact with friends and family, and joined in informal social activities. Although the mild intellectual impairment group were less likely to attain the following social outcomes than people with normal intellectual functioning, 67% had jobs, 73% were married, 62% had children and 54% owned their own homes. 12% participated in adult education. People with more severe intellectual impairment were less likely to attain these outcomes.

CONCLUSIONS

These outcomes highlight issues in current social policy and suggest efforts should be directed particularly towards promoting educational opportunities and developing social inclusion for people with ID.

Diagnostic instruments for dementia in older people with intellectual disability in clinical practice

There is a need for simple and reliable screening instruments for dementia in the intellectual disability (ID) population that can also be used to follow their progress, particularly if they are being treated with anti-dementia drugs. Commonly used tests for the general population such as the Mini Mental State Examination (MMSE) are not appropriate for many people with ID. This paper is a literature review of alternative instruments that have been used in research or recommended by experts since 1991 and have the potential to be used as screening instruments. Two types of tests have been identified: those administered to informants, and those that rely on direct assessment of the individual. The most promising informant rated screening tool in most adults with ID including Down syndrome (DS) diagnosis is the Dementia Questionnaire for Persons with Mental Retardation (DMR). However, sensitivity in single assessments is variable and cut-off scores need further optimisation. In those with DS, the Dementia Scale for Down Syndrome (DSDS) has good specificity but mediocre sensitivity. The Test for Severe Impairment and Severe Impairment Battery are two direct assessment tools that show promise as screening instruments, but need further evaluation.

A memory clinic for older people with intellectual disabilities

Cognitive decline in older people with intellectual disabilities (ID) is often under-recognized. Following the publication of the National Service Framework for Older People and the white paper Valuing People, older people with intellectual disabilities of all aetiologies should have access to a systematic assessment of their cognitive function in order to detect decline in cognition and adaptive skills and implement appropriate treatments as early as possible. The development of a memory clinic for older people with ID is described, including instruments used and characteristics of attendees. Such projects are in line with current UK government policies and can contribute to the improvement of standards of care and support research in this vulnerable group of people.

Long-term affective disorder in people with mild learning disability

BACKGROUND

Increased risk of affective disorder in learning disability has been reported, although the extent to which this is due to adverse social and material circumstances is uncertain and there have been potential limitations in the measurement of affective disorder.

AIMS

To determine risk of affective disorder in those classified with mild learning disability in the British 1946 birth cohort and to investigate whether this risk was accounted for by disadvantage in childhood and adulthood.

METHOD

Learning disability was defined as the equivalent of an IQ < or =69 at age 15 years. The Present State Examination at age 36 years and the Psychiatric Symptom Frequency Scale at age 43 years provided psychiatric outcome measures.

RESULTS

Learning disability was associated with a fourfold increase in risk of affective disorder, not accounted for by social and material disadvantage or by medical disorder.

CONCLUSIONS

Learning disability is strongly associated with risk of affective disorder, persisting well into midlife.

Randomized trial of psychotropic medication information leaflets for people with intellectual disability

People with intellectual disability (ID), like other patient groups, are known to have a limited knowledge of medication. Leaflets are seen as an appropriate means of providing patient information. To test the hypothesis that medication information leaflets would improve the knowledge and care of the target group, the present authors designed a randomized trial and planned to do subgroup analyses where appropriate. The participants were individually randomized to two groups. A control group was given verbal medication information by their nurse or psychiatrist, and a study group was given specifically designed leaflets in addition to verbal information. The present authors recruited 54 people with mild to moderate ID and mental illness, aged 18 years and older, who were taking psychiatric medications. Questionnaires administered by a blind interviewer recorded outcomes such as medication knowledge and satisfaction at two time points. The participants with mild ID in the leaflet group had significantly reduced medication knowledge and understanding. There were no significant differences in satisfaction with clinicians and medication. Patient information leaflets may confuse people with mild ID in the short term. Other patient groups with cognitive deficits may have similar outcomes. Evaluation of outcomes of health education initiatives is important.

Embryo sac development in some representatives of the tribe Cynodonteae (Poaceae)

Chloris virgata Sw., Cynodon dactylon (L.) Pers., Harpochloa falx (L. f.) Kuntze, and Tragus berteronianus Schult. have a Polygonum type of embryo sac development. Unreduced embryo sacs were found in Eustachys paspaloides (Vahl) Lanza Mattei,  Harpochloa falx, and  Rendlia altera (Rendle) Chiov. Both facultative and obligate apomixis were observed. The Hieracium type of embryo sac development was observed in the aposporic specimens.