Global Incidence of All-Cause Dementia
Year: 2026
Type: article
Abstract: Importance: Global dementia incidence estimates are limited by underrepresentation of low- and middle-income countries and heterogeneous analytic methods. Due to these limitations, true understanding of the global dementia landscape remains incomplete. Objective: To identify dementia incidence rates by age and sex in various regions worldwide (high-income countries and low- and middle-income countries) where data on clinically based dementia diagnoses were available. Data Sources: Retrospective community-based cohorts from the Cohort Studies of Memory in an International Consortium (COSMIC); baseline recruitment commenced between January 1990 and December 2011 and follow-up data were collected through the end of 2021. Data were analyzed from June 2024 to June 2025. Study Selection: Eligible studies included longitudinal COSMIC cohort studies with a clinically based diagnosis of dementia. Individual participant-level data from 22 population-based longitudinal cohorts (N = 38 418) spanning 18 countries or territories across 6 continents were included. Data Extraction and Synthesis: Data extraction and assessment of study quality and validity were conducted according to Meta-Analyses of Observational Studies in Epidemiology (MOOSE) guidelines. Individual participant-level data were meta-analyzed in a 2-step process using random intercepts for country and study at the global and regional levels and by country income level. Main Outcomes and Measures: For each study with a clinically based diagnosis, incidence rates for all-cause dementia were calculated and a 2-step meta-analysis was conducted. Using a person-years at risk framework with inverse-probability censoring weights and Poisson models, age- and sex-specific incidence were estimated and then standardized to the 2023 global age-sex population structure. Results: Across 287 632 person-years at risk, 3001 participants developed dementia. Age- and sex-standardized incidence was 9.7 (95% CI, 7.89-11.97) per 1000 person-years at risk. Age-standardized incidence was higher in women than men (10.6; 95% CI, 8.61-13.11 vs 8.6; 95% CI, 6.94-10.72). Standardized incidence was higher in low- and middle-income countries (13.6; 95% CI, 9.67-19.24) than in high-income countries (8.3; 95% CI, 6.57-10.54). Applying age- and sex-specific rates to the projected 2050 population yielded a projected 24.7 million new cases, assuming constant incidence over time. Conclusions and Relevance: The harmonized estimates presented in this study provide a comparable benchmark for global dementia incidence and inform planning for prevention, diagnosis, and memory-care services, particularly in underrepresented low- and middle-income country settings.
Source: JAMA Neurology
Authors: Ashleigh S. Vella, Rachel Visontay, Darren M. Lipnicki, Emma Nichols, Jaimie D. Steinmetz, Theo Vos, Anh Thy H. Nguyen, Juan J. Llibre-Rodriguez, Jorge Llibre-Guerra, Richard B. Lipton, Mindy J. Katz, Nikolaos Scarmeas, Maëlenn Guerchet, Pierre-Marie Preux, Karen Ritchie, Maria Skaalum Petersen, Ingmar Skoog, Elena Rolandi, Annalisa Davin, Michele Rossi, Ki Woong Kim, Ji Won Han, Dae Jong Oh, Steffi G. Riedel-Heller, Susanne Röhr, Alexander Pabst, Ding Ding, Qianhua Zhao, Xiaowen Zhou, Kaarin J. Anstey, Moyra E. Mortby, Nicolas Cherbuin, Antonio Lobo, Shifu Xiao, Hugh C. Hendrie, Sujuan Gao, Sebastian Köhler, Pascual Sánchez-Juan, Teodoro Del Ser, Meritxell Valentí-Soler, Marcia Scazufca, Allison E. Aiello, Jacqueline Dominguez, Roger Ho, John D. Crawford, Henry Brodaty, Louise Mewton, Perminder S. Sachdev, Ronald C Petersen, Richard Mayeux, Nicole Schupf, Yen-Ching Chen, Jen-Hau Chen, Kenji Narazaki, Michael Crowe, Frank Kee, Bernadette McGuinness, Nilton Custodio, Murali Krishna, Mary Ganguli, Suzana Shahar, Jacobijn Gussekloo, kenichi Meguro, Rose Anne Kenny, Ricardo O Guerra, Cristiano Gomes, liang-kung Chen, Richard Walker, Stella-Maria Paddick, Oye Gureje, Akin Ojagbemi, Linda Lam, Toshiharu Ninomiya, Rhoda Au, Eleonora d'Orsi, Carol Brayne, Kenneth Rockwood, Sabrina Noel, Erico Costa, Oscar H Del Brutto, Yuda Turana, Aquiles Salas, Ivonne Z Jimenez-Velazquez, Mariella G Arteaga, Ana Luisa Sosa, Daisy Acosta
Institutions: UNSW Sydney, The University of Sydney, University of Southern California, University of Washington, Institute for Health Metrics and Evaluation, University of Havana, Washington University in St. Louis, Albert Einstein College of Medicine, National and Kapodistrian University of Athens, Columbia University, Centre Hospitalier Universitaire de Limoges, Université d'Abomey-Calavi, Institut d’Epidémiologie et de Neurologie Tropicale, Institut de Recherche pour le Développement, Université de Limoges, Inserm, Institute for Neurosciences of Montpellier, Sahlgrenska University Hospital, Region Västra Götaland, University of Gothenburg, Fondazione Golgi Cenci, Seoul National University, Seoul National University Bundang Hospital, Leipzig University, Fudan University, Huashan Hospital, Neuroscience Research Australia, Australian National University, Universidad de Zaragoza, Centro de Investigación Biomédica en Red de Salud Mental, Instituto de Investigación Sanitaria Aragón, Shanghai Jiao Tong University, Shanghai Mental Health Center, Indiana University Indianapolis, Indiana University School of Medicine, Maastricht University, Instituto de Salud Carlos III, Fundacion Centro De Investigacion De Enfermedades Neurologicas, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, St. Luke's Medical Center, National University of Singapore, Hong Kong University of Science and Technology, Institute for Health Innovation & Technology, University of Hong Kong
Language: English
Subfield: Psychiatry and Mental health
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W7221521834