Cognitive and functional performance and plasma biomarkers of early Alzheimer's disease in Down syndrome.

INTRODUCTION: People with Down syndrome (DS) have a 75% to 90% lifetime risk of Alzheimer's disease (AD). AD pathology begins a decade or more prior to onset of clinical AD dementia in people with DS. It is not clear if plasma biomarkers of AD pathology are correlated with early cognitive and functional impairments in DS, and if these biomarkers could be used to track the early stages of AD in DS or to inform inclusion criteria for clinical AD treatment trials. METHODS: This large cross-sectional cohort study investigated the associations between plasma biomarkers of amyloid beta (Aß)42/40, total tau, and neurofilament light chain (NfL) and cognitive (episodic memory, visual-motor integration, and visuospatial abilities) and functional (adaptive behavior) impairments in 260 adults with DS without dementia (aged 25-81 years). RESULTS: In general linear models lower plasma Aß42/40 was related to lower visuospatial ability, higher total tau was related to lower episodic memory, and higher NfL was related to lower visuospatial ability and lower episodic memory. DISCUSSION: Plasma biomarkers may have utility in tracking AD pathology associated with early stages of cognitive decline in adults with DS, although associations were modest. Highlights: Plasma Alzheimer's disease (AD) biomarkers correlate with cognition prior to dementia in Down syndrome.Lower plasma amyloid beta 42/40 was related to lower visuospatial abilities.Higher plasma total tau and neurofilament light chain were associated with lower cognitive performance.Plasma biomarkers show potential for tracking early stages of AD symptomology.

A modified Cued Recall Test for detecting prodromal AD in adults with Down syndrome.

Introduction: The development of valid methods to diagnose prodromal Alzheimer's disease (AD) in adults with Down syndrome (DS) is one of the many goals of the Alzheimer's Biomarkers Consortium-Down Syndrome (ABC-DS). Methods: The diagnostic utility of a modified Cued Recall Test (mCRT) was evaluated in 332 adults with DS ranging from 25 to 81 years of age. Total recall was selected a priori, as the primary indicator of performance. Multiple regression and receiver-operating characteristic (ROC) analyses were used to compare diagnostic groups. Results: Performance on the mCRT, as indicated by the total recall score, was highly sensitive to differences between diagnostic groups. ROC areas under the curve (AUCs) ranging from 0.843 to 0.955, were observed. Discussion: The mCRT has strong empirical support for its use in clinical settings, as a valuable tool in studies targeting biomarkers of AD, and as a potential outcome measure in clinical trials targeting AD in this high-risk population.

Amyloid- ß and tau deposition influences cognitive and functional decline in Down syndrome.

This study investigates whether tau has (i) an independent effect from amyloid-ß on changes in cognitive and functional performance and (ii) a synergistic relationship with amyloid-ß in the exacerbation of decline in aging Down syndrome (DS). 105 participants with DS underwent baseline PET [18F]-AV1451 and PET [11C]PiB scans to quantify tau deposition in Braak regions II-VI and the Striatum and amyloid-ß status respectively. Linear Mixed Effects models were implemented to assess how tau and amyloid-ß deposition are related to change over three time points. Tau was a significant independent predictor of cognitive and functional change. The three-way interaction between time, [11C]PiB status and tau was significant in the models of episodic memory and visuospatial cognition. Baseline tau is a significant predictor of cognitive and functional decline, over and above the effect of amyloid-ß status. Results suggest a synergistic relationship between amyloid-ß status and tau as predictors of change in memory and visuospatial cognition.

Exploring electrophysiological markers of auditory predictive processes and pathological ageing in adults with Down's syndrome.

Down's syndrome is associated with pathological ageing and a propensity for early-onset Alzheimer's disease. The early symptoms of dementia in people with Down's syndrome may reflect frontal lobe vulnerability to amyloid deposition. Auditory predictive processes rely on the bilateral auditory cortices with the recruitment of frontal cortices and appear to be impaired in pathologies characterized by compromised frontal lobe. Hence, auditory predictive processes were investigated to assess Down's syndrome pathology and its relationship with pathological ageing. An auditory electroencephalography (EEG) global-local paradigm was presented to the participants, in which oddball stimuli could either violate local or higher level global rules. We characterised predictive processes in individuals with Down's syndrome and their relationship with pathological ageing, with a focus on the EEG event-related potential called Mismatch Negativity (MMN) and the P300. In Down's syndrome, we also evaluated the EEG components as predictor of cognitive decline 1 year later. We found that predictive processes of detection of auditory violations are overall preserved in Down's syndrome but also that the amplitude of the MMN to local deviancies decreases with age. However, the 1-year follow-up of Down's syndrome found that none of the ERPs measures predicted subsequent cognitive decline. The present study provides a novel characterization of electrophysiological markers of local and global predictive processes in Down's syndrome.

Cognitive outcome measures for tracking Alzheimer's disease in Down syndrome.

Down syndrome (DS) is now viewed as a genetic type of Alzheimer's disease (AD), given the near-universal presence of AD pathology in middle adulthood and the elevated risk for developing clinical AD in DS. As the field of DS prepares for AD clinical intervention trials, there is a strong need to identify cognitive measures that are specific and sensitive to the transition from being cognitively stable to the prodromal (e.g., Mild Cognitive Impairment-Down syndrome) and clinical AD (e.g., Dementia) stages of the disease in DS. It is also important to determine cognitive measures that map onto biomarkers of early AD pathology during the transition from the preclinical to the prodromal stage of the disease, as this transition period is likely to be targeted and tracked in AD clinical trials. The present chapter discusses the current state of research on cognitive measures that could be used to screen/select study participants and as potential outcome measures in future AD clinical trials with adults with DS. In this chapter, we also identify key challenges that need to be overcome and questions that need to be addressed by the DS field as it prepares for AD clinical trials in the coming years.

The Clinical and Neuropathological Features of Sporadic (Late-Onset) and Genetic Forms of Alzheimer's Disease.

The purpose of this review is to compare and highlight the clinical and pathological aspects of genetic versus acquired Alzheimer's disease: Down syndrome-associated Alzheimer's disease in (DSAD) and Autosomal Dominant Alzheimer's disease (ADAD) are compared with the late-onset form of the disease (LOAD). DSAD and ADAD present in a younger population and are more likely to manifest with non-amnestic (such as dysexecutive function features) in the prodromal phase or neurological features (such as seizures and paralysis) especially in ADAD. The very large variety of mutations associated with ADAD explains the wider range of phenotypes. In the LOAD, age-associated comorbidities explain many of the phenotypic differences.

Diagnostic and prognostic performance and longitudinal changes in plasma neurofilament light chain concentrations in adults with Down syndrome: a cohort study.

BACKGROUND: Adults with Down syndrome are at an ultra-high risk of Alzheimer's disease, but diagnosis of Alzheimer's disease in this population is challenging. We aimed to validate the clinical utility of plasma neurofilament light chain (NfL) for the diagnosis of symptomatic Alzheimer's disease in Down syndrome, assess its prognostic value, and establish longitudinal changes in adults with Down syndrome. METHODS: We did a multicentre cohort study, including adults with Down syndrome (≥18 years), recruited from six hospitals and university medical centres in France, Germany, Spain, the UK, and the USA, who had been assessed, followed up, and provided at least two plasma samples. Participants were classified by local clinicians, who were masked to biomarker data, as asymptomatic (ie, no clinical suspicion of Alzheimer's disease), prodromal Alzheimer's disease, or Alzheimer's disease dementia. We classified individuals who progressed along the Alzheimer's disease continuum during follow-up as progressors. Plasma samples were analysed retrospectively; NfL concentrations were measured centrally using commercial kits for biomarker detection. We used ANOVA to evaluate differences in baseline NfL concentrations, Cox regression to study their prognostic value, and linear mixed models to estimate longitudinal changes. To account for potential confounders, we included age, sex, and intellectual disability as covariates in the analyses. FINDINGS: Between Aug 2, 2010, and July 16, 2019, we analysed 608 samples from 236 people with Down syndrome: 165 (70%) were asymptomatic, 32 (14%) had prodromal Alzheimer's disease, and 29 (12%) had Alzheimer's disease dementia; ten [4%] participants were excluded because their classification was uncertain. Mean follow-up was 3·6 years (SD 1·6, range 0·6-9·2). Baseline plasma NfL concentrations showed an area under the receiver operating characteristic curve of 0·83 (95% CI 0·76-0·91) in the prodromal group and 0·94 (0·90-0·97) in the dementia group for differentiating from participants who were asymptomatic. An increase of 1 pg/mL in baseline NfL concentrations was associated with a 1·04-fold risk of clinical progression (95% CI 1·01-1·07; p=0·0034). Plasma NfL concentrations showed an annual increase of 3·0% (95% CI 0·4-5·8) per year in the asymptomatic non-progressors group, 11·5% (4·9-18·5) per year in the asymptomatic progressors group, and 16·0% (8·4-24·0) per year in the prodromal Alzheimer's disease progressors group. In participants with Alzheimer's disease dementia, NfL concentrations increased by a mean of 24·3% (15·3-34·1). INTERPRETATION: Plasma NfL concentrations have excellent diagnostic and prognostic performance for symptomatic Alzheimer's disease in Down syndrome. The longitudinal trajectory of plasma NfL supports its use as a theragnostic marker in clinical trials. FUNDING: AC Immune, La Caixa Foundation, Instituto de Salud Carlos III, National Institute on Aging, Wellcome Trust, Jérôme Lejeune Foundation, Medical Research Council, National Institute for Health Research, EU Joint Programme-Neurodegenerative Disease Research, Alzheimer's society, Deutsche Forschungsgemeinschaft, Stiftung für die Erforschung von Verhaltens und Umwelteinflüssen auf die menschliche Gesundheit, and NHS National Institute of Health Research Applied Research Collaborations East of England, UK.

Long-term cognitive outcome in adult survivors of an early childhood posterior fossa brain tumour.

PURPOSE: Posterior fossa brain tumours (PFT) and their treatment in young children are often associated with subsequent cognitive impairment. However, reported follow-up periods rarely exceed 10 years. This study reports very long-term cognitive consequences of surviving an early childhood PFT. METHODS: 62 adult survivors of a PFT, ascertained from a national register, diagnosed before 5 years of age, and a sibling control, received a single IQ assessment an average of 32 years (range 18-53) after initial diagnosis, using the Weschler Abbreviated Scale of Intelligence. Regression models were fitted to survivor-sibling pair differences on verbal and performance IQ (VIQ and PIQ) scores to investigate whether increasing time between PFT diagnosis and follow-up IQ assessment contributed to survivor-sibling IQ differences. RESULTS: At follow-up, survivors had, on average, VIQ 15 points and PIQ 19 points lower than their siblings. There was no significant effect of time since diagnosis on survivor-sibling VIQ difference. Survivors who received radiotherapy showed no significant effect of time since diagnosis on survivor-sibling PIQ difference. Survivors who did not receive radiotherapy demonstrated a trend for it to reduce. CONCLUSIONS: VIQ and PIQ deficits persist in adulthood, suggesting the effect of a fixed injury imposing on cognitive development, rather than an ongoing pathological process. IMPLICATIONS FOR CANCER SURVIVORS: The findings will help parents and others supporting survivors of an early life PFT to identify and plan for possible cognitive outcomes, and highlight the importance of early interventions to optimize cognitive function during the developmental period.

Amnestic and non-amnestic symptoms of dementia: An international study of Alzheimer's disease in people with Down's syndrome.

The presence of age-related neuropathology characteristic of Alzheimer's disease (AD) in people with Down syndrome (DS) is well-established. However, the early symptoms of dementia may be atypical and appear related to dysfunction of prefrontal circuitry. OBJECTIVE: To characterize the initial informant reported age-related neuropsychiatric symptoms of dementia in people with DS, and their relationship to AD and frontal lobe function. METHODS: Non-amnestic informant reported symptoms (disinhibition, apathy, and executive dysfunction) and amnestic symptoms from the CAMDEX-DS informant interview were analyzed in a cross-sectional cohort of 162 participants with DS over 30 years of age, divided into three groups: stable cognition, prodromal dementia, and AD. To investigate age-related symptoms prior to evidence of prodromal dementia we stratified the stable cognition group by age. RESULTS: Amnestic and non-amnestic symptoms were present before evidence of informant-reported cognitive decline. In those who received the diagnosis of AD, symptoms tended to be more marked. Memory impairments were more marked in the prodromal dementia than the stable cognition group (OR = 35.07; P < .001), as was executive dysfunction (OR = 7.16; P < .001). Disinhibition was greater in the AD than in the prodromal dementia group (OR = 3.54; P = .04). Apathy was more pronounced in the AD than in the stable cognition group (OR = 34.18; P < .001). CONCLUSION: Premorbid amnestic and non-amnestic symptoms as reported by informants increase with the progression to AD. For the formal diagnosis of AD in DS this progression of symptoms needs to be taken into account. An understanding of the unique clinical presentation of DS in AD should inform treatment options.

"Reasonable adjustments" under the UK's Equality Act 2010: An enquiry into the care and treatment to patients with intellectual disabilities in acute hospital settings.

OBJECTIVES: To understand the views of qualified medical practitioners regarding "reasonable adjustments" and the quality of the care and treatment provided to adults with intellectual disabilities when admitted to acute hospitals as inpatients. METHODS: Semi-structured interviews took place with 14 medical practitioners, seven from each of two acute hospitals, with a thematic analysis of the resulting data. RESULTS: All 14 medical practitioners reported problems in the diagnosis and treatment of patients with intellectual disabilities. Most participants attributed these difficulties to communication problems and/or behaviours that, in the context of a hospital ward, were non-conforming. However, a minority reported that, because they were likely to have multiple comorbid health conditions, patients with intellectual disabilities were more complex. In addition, half of all these respondents reported making little use of "reasonable adjustments" introduced to improve the quality of the care received by this group of patients. CONCLUSIONS: Medical practitioners should make better use of the "reasonable adjustments" introduced in the UK to address inequities in care and treatment received by patients with intellectual disabilities. However, training should also focus on the biomedical complexities often presented by these men and women.

Selection and visualisation of outcome measures for complex post-acute acquired brain injury rehabilitation interventions.

BACKGROUND: Outcome measurement challenges rehabilitation services to select tools that promote stakeholder engagement in measuring complex interventions. OBJECTIVES: To examine the suitability of outcome measures for complex post-acute acquired brain injury (ABI) rehabilitation interventions, report outcomes of a holistic, neuropsychological ABI rehabilitation program and propose a simple way of visualizing complex outcomes. METHODS: Patient/carer reported outcome measures (PROMS), experience measures (PREMS) and staff-rated measures were collected for consecutive admissions over 1 year to an 18-week holistic, neuropsychological rehabilitation programme at baseline, 18 weeks and 3- and 6-month follow-up. RESULTS: Engagement with outcome measurement was poorest for carers and at follow-up for all stakeholders. Dependence, abilities, adjustment, unmet needs, symptomatology including executive dysfunction, and self-reassurance showed improvements at 18 weeks. Adjustment, social participation, perceived health, symptomatology including dysexecutive difficulties, and anxiety were worse at baseline for those who did not complete rehabilitation, than those who did. A radar plot facilitated outcome visualization. CONCLUSIONS: Engagement with outcome measurement was best when time and support were provided. Supplementing patient- with staff-rated and attendance measures may explain missing data and help quantify healthcare needs. The MPAI4, EBIQ and DEX-R appeared suitable measures to evaluate outcomes and distinguish those completing and not completing neuropsychological rehabilitation.

Tensions between policy and practice: A qualitative analysis of decisions regarding compulsory admission to psychiatric hospital.

The use of detention for psychiatric treatment is widespread and sometimes necessary. International human rights law requires a legal framework to safeguard the rights to liberty and personal integrity by preventing arbitrary detention. However, research suggests that extra-legal factors may influence decisions to detain. This article presents observational and interview data to describe how decisions to detain are made in practice in one jurisdiction (England and Wales) where a tension between policy and practice has been described. The analysis shows that practitioners mould the law into 'practical criteria' that appear to form a set of operational criteria for identifying cases to which the principle of soft paternalism may be applied. Most practitioners also appear willing, albeit often reluctantly, to depart from their usual reliance on the principle of soft paternalism and authorise detention of people with the capacity to refuse treatment, in order to prevent serious harm. We propose a potential resolution for the tension between policy and practice: two separate legal frameworks to authorise detention, one with a suitable test of capacity, used to enact soft paternalism, and the other to provide legal justification for detention for psychiatric treatment of the small number of people who retain decision-making capacity but nonetheless choose to place others at risk by refusing treatment. This separation of detention powers into two systems, according to the principle that justifies the use of detention would be intellectually coherent, consistent with human rights instruments and, being consistent with the apparent moral sentiments of practitioners, less prone to idiosyncratic interpretations in practice.

Offending by people with intellectual disabilities in community settings: a preliminary examination of contextual factors.

BACKGROUND: While several validated measures of the life circumstances of people with intellectual disabilities (ID) have been developed, this stream of research has not yet been well integrated with environmentally oriented criminological theory to explain offending among people with ID. In this study, we attempt to provide a preliminary integration through an investigation of the relationship between contemporary life experiences, well-being, choice and offending among people with ID, exploring the relevance of two classic criminological theories (theories of strain and social control). MATERIALS AND METHODS: Questionnaire measures were used to compare a range of 'ordinary' life experiences [the 'Life Experiences Checklist' (LEC)], subjective well-being (the 'Personal Well-being Index - ID') and the extent of choice (the 'Choice Questionnaire'), between offenders (N = 27) and non-offenders (N = 19) with ID recruited through integrated (NHS and Local Authority) multi-disciplinary teams (community teams for adults with learning disabilities). RESULTS: Using regression analyses to explore the strength of associations with offending, it was found that an indicator of impoverished personal relationships, from the LEC provided the best predictor of offending. This finding appears to favour criminological explanations based on social control. CONCLUSIONS: Existing measures of life circumstances can be used to explore environmentally oriented criminological theories, bringing benefits to our understanding and treatment of offenders with ID living in community settings.

Prevalence, associations, and predictors of apathy in adult survivors of infantile (<5 years of age) posterior fossa brain tumors.

BACKGROUND: Apathy is associated with pervasive and disadvantageous effects on daily functioning. It has been observed transiently in some children after surgery for posterior fossa tumors. In this study, our objective was to examine prevalence, associations, and predictors of apathy in adult survivors of an infantile posterior fossa brain tumor (PFT). METHODS: One hundred seventeen adult survivors of a childhood PFT diagnosed before age 5 years and 60 of their siblings were assessed in a cross-sectional study a mean of 32 years (range, 18-53 years) after survivors' initial tumor diagnoses, using the Marin Apathy Evaluation Scale (AES), the Weschler Abbreviated Scale of Intelligence and the Composite International Diagnostic Interview for psychiatric disorders. RESULTS: Marin Apathy Evaluation Scale, the Weschler Abbreviated Scale of Intelligence reached or exceeded a criterion score for clinically significant apathy in 35% of survivors, compared with 18% in a sibling comparison group. In both siblings and survivors, apathy was associated with lower verbal and full-scale IQ and, among survivors, with having undergone partial rather than total tumor resection (independent of irradiation status). Apathy was not related to presence of concurrent International Classification of Diseases, 10(th) Revision, depression. Female sex was associated with late apathy after a PFT, with increased likelihood of women reaching the apathy criterion relative to men if they were survivors. CONCLUSIONS: Clinically significant and potentially treatable apathy occurs relatively commonly in adult survivors of an infantile childhood PFT, particularly women. Clinicians, including those managing posterior fossa pathology in very young children, should be aware of this association, and future research should clarify whether specific treatment-related variables are implicated in increasing this risk of apathy.

An evaluation of the EQUIP treatment programme with men who have intellectual or other developmental disabilities.

BACKGROUND: The Equipping Youth to Help One Another Programme (EQUIP) was designed for young offenders to address a developmental delay in moral reasoning, distorted cognitions and social skills. METHODS: The present authors undertook a single case series study and piloted an adapted version of the EQUIP programme with three men with intellectual disabilities and four men with a diagnosis of Asperger Syndrome, all of whom were detained in a medium-secure forensic unit for people with intellectual disabilities. Treatment was delivered over a 12-week period, and participants took part in four-one-hour sessions per week. RESULTS: The results suggested that treatment was successful at increasing moral reasoning ability, reducing distorted cognitions and improving ability to choose effective solutions to problems. However, treatment did not have a significant effect upon anger. CONCLUSIONS: The EQUIP programme is a promising treatment, but further research is needed to investigate its effectiveness with men with intellectual or other developmental disabilities.

Decision-making difficulties experienced by adults with autism spectrum conditions.

Autobiographical and clinical accounts, as well as a limited neuropsychological research literature, suggest that, in some situations, men and women with autism spectrum conditions (ASCs) may have difficulty making decisions. Little is known, however, about how people with ASCs experience decision-making or how they might best be supported to make decisions for themselves. In this study, we compared the decision-making experiences of adults with and without ASCs (n=38 and n=40, respectively) using a novel questionnaire and the General Decision Making Style inventory (GDMS, Scott & Bruce, 1995). The participants with ASCs reported experiencing several problems in decision-making more frequently than the comparison group, and were more likely to report avoidance of decision-making, as measured using the GDMS. The findings highlight areas of potential future research and inform suggestions for supporting adults with ASCs during decision-making.

Relationships among moral reasoning, empathy, and distorted cognitions in men with intellectual disabilities and a history of criminal offending.

Eighty men, spread equally across 4 groups, were recruited, including men with and without intellectual disabilities. The men were either criminal offenders or nonoffenders. Participants completed measures of moral reasoning, empathy, and distorted cognitions. The results indicated that the moral reasoning abilities of offenders with intellectual disabilities were developmentally delayed but were still more mature than those of nonoffenders with intellectual disabilities. Offenders without intellectual disabilities had less mature moral reasoning abilities than nonoffenders without intellectual disabilities. The differences may be partially accounted for by intellectual ability. The results also indicated that the relationship between empathy and distorted cognitions was mediated by moral reasoning. The findings have implications for the use of psychological interventions with offenders with intellectual disabilities.

Measuring social desirability amongst men with intellectual disabilities: the psychometric properties of the Self- and Other-Deception Questionnaire-Intellectual Disabilities.

BACKGROUND: Social desirability has been construed as either inaccurately attributing positive characteristics to oneself (self-deception), or inaccurately denying that one possesses undesirable characteristics to others (other-deception or impression management). These conceptualisations of social desirability have not been considered in relation to people with intellectual disabilities (IDs), but they are important constructs to consider when undertaking a psychological assessment of an individual, especially within forensic contexts. Therefore, we revised two existing measures of self- and other-deception and considered their psychometric properties. METHODS: Thirty-two men with mild IDs and 28 men without IDs completed the Self- and Other-Deception Questionnaires-Intellectual Disabilities (SDQ-ID and ODQ-ID) on two occasions, two weeks apart. RESULTS: Men with IDs scored significantly higher on the SDQ-ID and the ODQ-ID than men without IDs. However, these differences disappeared when Full Scale IQ, Verbal IQ and Performance IQ were controlled in relation to the SDQ-ID, and partially disappeared in relation to the ODQ-ID. The SDQ-ID and the ODQ-ID had substantial internal consistency in relation to men with IDs (k=0.82 and 0.84 respectively). The test-retest reliability of the SDQ-ID was good (r(i)=0.68), while the test-retest reliability of the ODQ-ID was moderate (r(i)=0.56), for men with IDs. The SDQ-ID had moderate (k=0.60) and the ODQ-ID had substantial (k=0.70) internal consistency in relation to men without IDs, while the test-retest reliability of the SDQ-ID was excellent (r(i)=0.87) as was the case for the ODQ-ID (r(i)=0.85). CONCLUSIONS: The SDQ-ID and the ODQ-ID have satisfactory psychometric properties in relation to men with and without IDs. Future research using these instruments is proposed.

The psychometric properties of the Socio-Moral Reflection Measure--Short Form and the Moral Theme Inventory for men with and without intellectual disabilities.

Drawing conclusions from the literature regarding the moral development of people with intellectual disabilities (IDs) is difficult because of the use of unstandardised and idiosyncratic measures. In order to address this short-coming, a moral reasoning production measure (the Socio-Moral Reflection Measure--Short Form; SRM-SF) and a recognition measure (the Moral Theme Inventory; MTI) were presented to men with and without IDs who had no known history of engaging in illegal behaviour. The instruments were completed on two occasions, separated by a two-week interval, in order to investigate their basic psychometric properties. The results indicated that there was a strong relationship between the MTI and the SRM-SF, suggesting that the MTI has convergent validity. The internal consistency of the MTI and the SRM-SF ranged from moderate to substantial for both men with and without IDs. However, the test-retest reliability of the MTI was poor for men with IDs, while it was good for men without IDs. The test-retest reliability of the SRM-SF was good for both men with and without IDs. Comparison of the moral reasoning abilities of men with and without IDs suggested that many of the differences between the two groups could be accounted for by general intellectual functioning. The exception was overall score on the SRM-SF and moral reasoning in relation to the law, where men with IDs scored at stage 2(1), when intelligence was controlled. The results were interpreted by suggesting that the relationship between moral reasoning and illegal behaviour may take an inverted U curve shape, moderated by intelligence.

Substitute decision-making for adults with intellectual disabilities living in residential care: learning through experience.

In the UK, current policies and services for people with mental disorders, including those with intellectual disabilities (ID), presume that these men and women can, do, and should, make decisions for themselves. The new Mental Capacity Act (England and Wales) 2005 (MCA) sets this presumption into statute, and codifies how decisions relating to health and welfare should be made for those adults judged unable to make one or more such decisions autonomously. The MCA uses a procedural checklist to guide this process of substitute decision-making. The personal experiences of providing direct support to seven men and women with ID living in residential care, however, showed that substitute decision-making took two forms, depending on the type of decision to be made. The first process, 'strategic substitute decision-making', paralleled the MCA's legal and ethical framework, whilst the second process, 'relational substitute decision-making', was markedly different from these statutory procedures. In this setting, 'relational substitute decision-making' underpinned everyday personal and social interventions connected with residents' daily living, and was situated within a framework of interpersonal and interdependent care relationships. The implications of these findings for residential services and the implementation of the MCA are discussed.