The epidemiology of mild cognitive impairment (MCI) and Alzheimer’s disease (AD) in community-living seniors: protocol of the MemoVie cohort study, Luxembourg

BACKGROUND: Cognitive impairment and Alzheimer’s disease (AD) are increasingly considered a major public health problem. The MemoVie cohort study aims to investigate the living conditions or risk factors under which the normal cognitive capacities of the senior population in Luxembourg (≥ 65 year-old) evolve (1) to mild cognitive impairment (MCI) – transitory non-clinical stage – and (2) to AD. Identifying MCI and AD predictors undeniably constitutes a challenge in public health in that it would allow interventions which could protect or delay the occurrence of cognitive disorders in elderly people. In addition, the MemoVie study sets out to generate hitherto unavailable data, and a comprehensive view of the elderly population in the country. METHODS/DESIGN: The study has been designed with a view to highlighting the prevalence in Luxembourg of MCI and AD in the first step of the survey, conducted among participants selected from a random sample of the general population. A prospective cohort is consequently set up in the second step, and appropriate follow-up of the non-demented participants allows improving the knowledge of the preclinical stage of MCI. Case-control designs are used for cross-sectional or retrospective comparisons between outcomes and biological or clinical factors. To ensure maximal reliability of the information collected, we decided to opt for structured face to face interviews. Besides health status, medical and family history, demographic and socio-cultural information are explored, as well as education, habitat network, social behavior, leisure and physical activities. As multilingualism is expected to challenge the cognitive alterations associated with pathological ageing, it is additionally investigated. Data relative to motor function, including balance, walk, limits of stability, history of falls and accidents are further detailed. Finally, biological examinations, including ApoE genetic polymorphism are carried out. In addition to standard blood parameters, the lipid status of the participants is subsequently determined from the fatty acid profiles in their red blood cells. The study obtained the legal and ethical authorizations. DISCUSSION: By means of the multidisciplinary MemoVie study, new insights into the onset of cognitive impairment during aging should be put forward, much to the benefit of intervention strategies as a whole

Contextual momentary assessment of speech-in-noise listening situations among hearing aid users : validity and reliability

Currently, all hearing aid benefit outcome measures rely on retrospective self-report, which can often be inaccurate due to memory decay, recollection biases, and the use of cognitive heuristics. Contextual momentary assessment (CMA) involves repeated collection of real-time data on an individual’s experience in their natural environment; CMAs circumvent the error and bias related to retrospective assessments, making them more ecologically valid for capturing day-to-day variations in experiences. The purpose of the present paper was to answer three research questions: (a) Is CMA capable of facilitating valid and reliable evaluations of subjective listening experiences in lab-controlled acoustic conditions?; (b) Is CMA validity and reliability altered significantly by the timing of the CMA relative to the listening event (Experiment I)?; (c) Is CMA validity and reliability altered by the presence of, or focus on a secondary task (Experiment II)? To address these research questions, this study employed a block-randomized, within-subject design where 12 participants with sensorineural hearing loss were fitted with hearing aid(s), and completed CMA ratings based on listening situations where they performed a sentence repetition task. The study was comprised of two experiments involving three independent variables: (a) speech level; (b) signal-to-noise ratio (SNR); (c) CMA timing (Experiment I), or task focus (Experiment II). CMAs were composed of four rating dimensions: intelligibility, noisiness, listening effort, and loudness. For the listening situations employed in this lab study, the reliability, construct validity, and criterion validity results were as follows: (a) intelligibility ratings were reliable, demonstrated construct validity, and had the strongest correlation with intelligibility scores when the CMA was completed after listening situations where there was no secondary task; (b) noisiness ratings were reliable, demonstrated construct validity, and correlated the strongest with measured background noise intensities when rated while experiencing the listening situation; (c) listening effort ratings were unreliable and had questionable construct validity; (d) loudness ratings were reliable, demonstrated construct validity, and correlated the strongest with measured speech intensities when rated while experiencing the listening situation. Based on these results, CMA ratings of intelligibility, loudness, and noisiness, but not listening effort, show potential to be useful for measuring hearing aid benefit.Medicine, Faculty ofAudiology and Speech Sciences, School ofGraduat