Daily Function as Predictor of Dementia in Cognitive Impairment, No Dementia (CIND) and Mild Cognitive Impairment (MCI): An 8-Year Follow-Up in the ILSA Study

Article type: Research Article

Authors: Di Carlo, Antonio^{a; *} | Baldereschi, Marzia^a | Lamassa, Maria^b | Bovis, Francesca^b | Inzitari, Marco^c | Solfrizzi, Vincenzo^d | Panza, Francesco^{e; f} | Galluzzo, Lucia^g | Scafato, Emanuele^g | Inzitari, Domenico^{a; b} | for the Italian Longitudinal Study on Aging Working Group¹

Affiliations: [a] Institute of Neuroscience, Italian National Research Council, Florence, Italy | [b] Department of NEUROFARBA, Neuroscience Section, University of Florence, Florence, Italy | [c] Hospital Sociosanitari Pere Virgili, Barcelona, Spain | [d] Geriatric Medicine-Memory Unit, Rare DiseaseCentre, Department of Interdisciplinary Medicine, University of Bari Aldo Moro, Bari, Italy | [e] Neurodegenerative Disease Unit, Department of Basic Medicine, Neuroscience, and Sense Organs, University of Bari Aldo Moro, Bari, Italy | [f] Geriatric Unit & Laboratory of Gerontology and Geriatrics, Department of Medical Sciences, IRCCS “Casa Sollievo della Sofferenza”, San Giovanni Rotondo, Foggia, Italy | [g] Population Health and Health Determinants Unit, National Centre for Epidemiology, Surveillance and Health Promotion (CNESPS), Istituto Superiore di Sanità (ISS), Rome, Italy

Correspondence: [*] Correspondence to: Antonio Di Carlo, MD, Institute of Neuroscience, Italian National Research Council, Via Madonna del Piano, 10, 50019 Sesto Fiorentino, Florence, Italy. Tel.: +39 055 5225032; Fax: +39 055 5225035; E-mail: [email protected].

Note: [1] The ILSA Working Group: E. Scafato, G. Farchi, L. Galluzzo, C. Gandin, Istituto Superiore di Sanitá, Rome; A. Capurso, F. Panza, V. Solfrizzi, V. Lepore, P. Livrea, University of Bari; L. Motta, G. Carnazzo, M. Motta, P. Bentivegna, University of Catania; S. Bonaiuto, G. Cruciani, F. Fini, A. Vesprini, D. Postacchini, Italian National Research Centre on Aging (INRCA), Fermo; D. Inzitari, L. Amaducci, University of Florence; A. Di Carlo, M. Baldereschi, Institute of Neuroscience, National Research Council of Italy (CNR), Florence; A. Ghetti, R. Vergassola, Health Area 10, Florence; C. Gandolfo, M. Conti, University of Genoa; N. Canal, M. Franceschi, San Raffaele Institute, Milan; G. Scarlato, L. Candelise, E. Scarpini, University of Milan; F. Rengo, P. Abete, F. Cacciatore, F. Covelluzzi, University of Naples; G. Enzi, L. Battistin, G. Sergi, G. Crepaldi, M. Bressan, G. Bortolan, University of Padua; S. Maggi, N. Minicuci, M. Noale, National Research Council of Italy (CNR), Aging Section, Padua; F. Grigoletto, E. Perissinotto, Institute of Hygiene, University of Padua; P. Carbonin, Universitá Cattolica del Sacro Cuore, Rome.

Abstract: Background: Preclinical cognitive changes may predict an increased risk of dementia, allowing selection of subgroups as possible targets for preventive or therapeutic interventions. Objective: To evaluate the predictive effect of daily functioning and motor performance (MP) on the progression to dementia in normal cognition, cognitive impairment, no dementia (CIND), and mild cognitive impairment (MCI). Methods: The Italian Longitudinal Study on Aging is a large population-based survey on age-related diseases of the cardiovascular and nervous systems. After the baseline assessment, to detect prevalent cases of cognitive impairment and dementia, participants were re-examined at 4-year and 8-year follow-ups. Functional independence was evaluated using the Index of Activities of Daily Living (ADL) and the Instrumental Activities of Daily Living (IADL) Scale. A six-test battery was used to assess MP. Results: Overall, 2,386 individuals were included, for a total of 16,545 person-years. Eight-year incidence of dementia (per 1,000 person-years) was 12.69 in total sample, 9.86 in subjects with normal cognition at baseline, 22.99 in CIND, and 21.43 in MCI. Progression to dementia was significantly higher with increasing baseline ADL and IADL impairment, and with a worse MP. In Cox regression analyses controlled for demographics and major age-related conditions, increased IADL impairment was the stronger predictor of progression to dementia (p < 0.001), with HR ranging from 2.16 (95% CI, 0.82–5.70) to 9.57 (95% CI, 3.40–26.91) in subjects with MCI at baseline. Conclusions: Inclusion of IADL in the MCI construct significantly improves the prediction of dementia. Individuation of different transition rates is required to plan cost-effective interventions.

Keywords: Dementia, instrumental activities of daily living, longitudinal studies, mild cognitive impairment, motor performance

DOI: 10.3233/JAD-160087

Journal: Journal of Alzheimer's Disease, vol. 53, no. 2, pp. 505-515, 2016