A neuroimaging proof of principle study of Down's syndrome and dementia: ethical and methodological challenges in intrusive research

The pattern of amyloid accumulation in the brains of adults with Down syndrome

INTRODUCTION

Adults with Down syndrome (DS) invariably develop Alzheimer's disease (AD) neuropathology. Understanding amyloid deposition in DS can yield crucial information about disease pathogenesis.

METHODS

Forty-nine adults with DS aged 25-65 underwent positron emission tomography with Pittsburgh compound-B (PIB). Regional PIB binding was assessed with respect to age, clinical, and cognitive status.

RESULTS

Abnormal PIB binding became evident from 39 years, first in striatum followed by rostral prefrontal-cingulo-parietal regions, then caudal frontal, rostral temporal, primary sensorimotor and occipital, and finally parahippocampal cortex, thalamus, and amygdala. PIB binding was related to age, diagnostic status, and cognitive function.

DISCUSSION

PIB binding in DS, first appearing in striatum, began around age 40 and was strongly associated with dementia and cognitive decline. The absence of a substantial time lag between amyloid accumulation and cognitive decline contrasts to sporadic/familial AD and suggests this population's suitability for an amyloid primary prevention trial.

Participant experience of invasive research in adults with intellectual disability

Clinical research is a necessity if effective and safe treatments are to be developed. However, this may well include the need for research that is best described as 'invasive' in that it may be associated with some discomfort or inconvenience. Limitations in the undertaking of invasive research involving people with intellectual disabilities (ID) are perhaps related to anxieties within the academic community and among ethics committees; however, the consequence of this neglect is that innovative treatments specific to people with ID may not be developed. Such concerns are likely to continue while there is limited published knowledge regarding the actual experiences of people with ID who have participated in invasive clinical research. As part of a pilot study trialling the novel use of a surgically inserted device to curb overeating in people with Prader-Willi syndrome (PWS) we have investigated the experience of research through semistructured qualitative interviews involving three participants and their carers. Thematic analysis revealed that the adults with PWS and their family carers rated their participation positively, seeing it as a rewarding and enriching experience. This brief report discusses findings from our interview data in order to highlight strategies which may ensure that research is acceptable to participants, meets the necessary ethical standards and is able to achieve the aims set out by the researchers. To our knowledge, this is the first study to record experiences directly from people with PWS and their carers regarding their involvement in invasive clinical research.

Recruitment to intellectual disability research: a qualitative study

BACKGROUND

Difficulties in the recruitment of adults with intellectual disability (ID) to research studies are well described but little studied. The aim of this study was to investigate the difficulties in recruiting to a specific research project, in order to inform future recruitment to ID research.

METHODS

Individual semi-structured interviews were held between September 2009 and May 2010 with people who had been involved as intermediaries in recruitment to the research project. These were transcribed verbatim and were independently analysed by two researchers using the Framework approach, who then agreed upon the key emerging themes.

RESULTS

Ten interviews were analysed. A number of themes arose, including participant factors (interview anxiety, difficulties in understanding the concept of research, worry about negative feedback), the importance of the researcher (using a personal approach, meeting potential participants prior to recruitment) and motivators [enjoyment of the research interview (participant), obtaining a medical assessment (carer)]. The themes were then used to generate strategies to improve recruitment to ID research: these include the research team applying a more personal approach, developing the recruitment process to allow for multiple meetings with potential participants, and considering motivators for both participants and carers.

CONCLUSIONS

This study has used the experiences of intermediaries to identify strategies for improving recruitment to future ID research. This has implications in terms of both time and money. However, successful recruitment is essential to ID research, and we hope that the study will be used by ID researchers to review and improve their recruitment processes.