Fauria K, Minguillon C, Knezevic I, Tort-Colet N, Stankeviciute L, Hernández L, Rădoi A, Deulofeu C, Fuentes-Julián S, Turull I, Fusté D, Sánchez-Benavides G, Arenaza-Urquijo EM, Suárez-Calvet M, Holst SC, Garcés P, Mueggler T, Zetterberg H, Blennow K, Arqueros A, Iranzo Á, Domingo Gispert J, Molinuevo JL, Grau-Rivera O
Introduction: The growing worldwide prevalence of Alzheimer's disease (AD) and the lack of effective treatments pose a dire medical challenge. Sleep disruption is also prevalent in the ageing population and is increasingly recognised as a risk factor and an early sign of AD. The ALFASleep project aims to characterise sleep with subjective and objective measurements in cognitively unimpaired middle/late middle-aged adults at increased risk of AD who are phenotyped with fluid and neuroimaging AD biomarkers. This will contribute to a better understanding of the pathophysiological mechanisms linking sleep with AD, thereby paving the way for the development of non-invasive biomarkers and preventive strategies targeting sleep.
Methods and analysis: We will invite 200 participants enrolled in the ALFA+ (for ALzheimer and FAmilies) prospective observational study to join the ALFASleep study. ALFA+ participants are cognitively unimpaired middle-aged/late middle-aged adults who are followed up every 3 years with a comprehensive set of evaluations including neuropsychological tests, blood and cerebrospinal fluid (CSF) sampling, and MRI and positron emission tomography acquisition. ALFASleep participants will be additionally characterised with actigraphy and CSF-orexin-A measurements, and a subset (n=90) will undergo overnight polysomnography. We will test associations of sleep measurements and CSF-orexin-A with fluid biomarkers of AD and glial activation, neuroimaging outcomes and cognitive performance. In case we found any associations, we will test whether changes in AD and/or glial activation markers mediate the association between sleep and neuroimaging or cognitive outcomes and whether sleep mediates associations between CSF-orexin-A and AD biomarkers.
Ethics and dissemination: The ALFASleep study protocol has been approved by the independent Ethics Committee Parc de Salut Mar, Barcelona (2018/8207/I). All participants have signed a written informed consent before their inclusion (approved by the same ethics committee). Study findings will be presented at national and international conferences and submitted for publication in peer-reviewed journals.
Fauria K, Minguillon C, Knezevic I, Tort-Colet N, Stankeviciute L, Hernández L, Rădoi A, Deulofeu C, Fuentes-Julián S, Turull I, Fusté D, Sánchez-Benavides G, Arenaza-Urquijo EM, Suárez-Calvet M, Holst SC, Garcés P, Mueggler T, Zetterberg H, Blennow K, Arqueros A, Iranzo Á, Domingo Gispert J, Molinuevo JL, Grau-Rivera O. Exploring cognitive and biological correlates of sleep quality and their potential links with Alzheimer's disease (ALFASleep project): protocol for an observational study. BMJ Open. 2022 Dec 30;12(12):e067159. doi: 10.1136/bmjopen-2022-067159. PMID: 36585141; PMCID: PMC9809234.