ICC-dementia (International Centenarian Consortium - dementia): an international consortium to determine the prevalence and incidence of dementia in centenarians across diverse ethnoracial and sociocultural groups

Henry Brodaty, Claudia Woolf, Stacy Andersen, Nir Barzilai, Carol Brayne, Karen Siu-Lan Cheung, Maria M. Corrada, John D. Crawford, Catriona Daly, Yasuyuki Gondo, Bo Hagberg, Nobuyoshi Hirose, Henne Holstege, Claudia Kawas, Jeffrey Kaye, Nicole A. Kochan, Bobo Hi-Po Lau, Ugo Lucca, Gabriella Marcon, Peter MartinLeonard W. Poon, Robyn Richmond, Jean-Marie Robine, Ingmar Skoog, Melissa J. Slavin, Jan Szewieczek, Mauro Tettamanti, Jose Vina, Thomas Perls, Perminder S. Sachdev

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Background
Considerable variability exists in international prevalence and incidence estimates of dementia. The accuracy of estimates of dementia in the oldest-old and the controversial question of whether dementia incidence and prevalence decline at very old age will be crucial for better understanding the dynamics between survival to extreme old age and the occurrence and risk for various types of dementia and comorbidities. International Centenarian Consortium – Dementia (ICC-Dementia) seeks to harmonise centenarian and near-centenarian studies internationally to describe the cognitive and functional profiles of exceptionally old individuals, and ascertain the trajectories of decline and thereby the age-standardised prevalence and incidence of dementia in this population. The primary goal of the ICC-Dementia is to establish a large and thorough heterogeneous sample that has the power to answer epidemiological questions that small, separate studies cannot. A secondary aim is to examine cohort-specific effects and differential survivorship into very old age. We hope to lay the foundation for further investigation into risk and protective factors for dementia and healthy exceptional brain ageing in centenarians across diverse ethnoracial and sociocultural groups.

Methods
Studies focusing on individuals aged ≥95 years (approximately the oldest 1 percentile for men, oldest 5th percentile for women), with a minimum sample of 80 individuals, including assessment of cognition and functional status, are invited to participate. There are currently seventeen member or potential member studies from Asia, Europe, the Americas, and Oceania. Initial attempts at harmonising key variables are in progress.

Discussion
General challenges facing large, international consortia like ICC-Dementia include timely and effective communication among member studies, ethical and practical issues relating to human subject studies and data sharing, and the challenges related to data harmonisation. A specific challenge for ICC-Dementia relates to the concept and definition of’abnormal’ in this exceptional group of individuals who are rarely free of physical, sensory and/or cognitive impairments.
Original languageEnglish
Article number52
JournalBMC Neurology
Volume16
DOIs
Publication statusPublished - 21 Apr 2016

Cite this