The incidence of registered dementia cases has increased slightly over a 23-year period (1992 to 2014) in the Netherlands, according to a study published by Emma van Bussel and colleagues from the Academic Medical Center Amsterdam, The Netherlands, in PLOS Medicine's Special Issue on Dementia.
The researchers collected data on dementia diagnoses for persons aged 60 years and over from general practitioner networks for the years 1992 to 2014, including data on more than 800,000 older people and 23,186 incident dementia cases. They estimate that the annual growth in dementia incidence rate is 2.1% (95% CI 0.5% to 3.8%), with incidence rates 1.08 (95% CI 1.04 to 1.13) times higher for women compared to men. The authors say that increased awareness of dementia by patients and doctors in more recent years may have influenced dementia diagnosis by general practitioners in electronic health records, and needs to be taken into account when interpreting the data.
In a linked Perspective, Eric Larson discusses the findings in light of previous cohort studies that have reported a recent decline in dementia incidence rates and highlights that studies on the incidence and prevalence of dementia can provide insights into possible strategies to control dementia.
He says: "We must plan for increasing numbers of predominantly older people with dementia in the decades to come including addressing the growing need for long-term care in the context of a significant decline in the availability of family caregivers."
This research was supported by the Dutch Ministry of Health, Welfare and Sports (grant number 50-50110-98-020), the Dutch Innovation Fund of Collaborative Health Insurances (grant number 05-234), and Netherlands Organisation for Health Research and Development (grant number 62000015 and 839110003). The contribution of author PMC for this work has received support from the EU/EFPIA Innovative Medicines Initiative Joint Undertaking (EMIF grant number 115372). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
I have read the journal's policy and the authors of this manuscript have the following competing interests: CB is a member of the Editorial Board of PLOS Medicine and a Guest Editor for the Dementia Special Issue. FEM has received research grants from the UK Medical Research Council, Alzheimers Society UK, and received travel grants from the National Institutes of Health. PMC joined F. Hoffmann La Roche Ltd., a global health care company, after the study was completed but before publication. PMC is currently a full-time employee of, and own shares at, Roche.
van Bussel EF, Richard E, Arts DL, Nooyens ACJ, Coloma PM, de Waal MWM, et al. (2017) Dementia incidence trend over 1992-2014 in the Netherlands: Analysis of primary care data. PLoS Med 14(3): e1002235. doi:10.1371/journal.pmed.1002235
Department of General Practice, Academic Medical Center Amsterdam, Amsterdam, The Netherlands
Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, The Netherlands
Department of Neurology, Academic Medical Center Amsterdam, Amsterdam, The Netherlands
Centre for Nutrition, Prevention and Health Services, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
Department of Medical Informatics, Erasmus University Medical Center, Rotterdam, The Netherlands
Department of Public Health and Primary Care, Leiden University Medical Center, Leiden, The Netherlands
CAPHRI School for Public Health and Primary Care, Department of Family Medicine, Maastricht University, Maastricht, The Netherlands
Academic Center for General Practice, Department of Public Health and Primary Care, KU Leuven, Leuven, Belgium
Department of Primary and Community Care, Radboud University Medical Center, Nijmegen, The Netherlands
Department of General Practice, Netherlands Institute for Health Services Research, Utrecht, The Netherlands
Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands
Institute for Health and Society, Newcastle University, Newcastle upon Tyne, United Kingdom Institute of Public Health, Cambridge University, Cambridge, United Kingdom
IN YOUR COVERAGE PLEASE USE THIS URL TO PROVIDE ACCESS TO THE FREELY AVAILABLE PAPER: http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1002235
The authors received no funding for this work.
The authors have declared that no competing interests exist.
Larson EB, Langa KM (2017) What's the "Take Home" from Research on Dementia Trends? PLoS Med 14(3): e1002236. doi:10.1371/journal.pmed.1002236
Group Health Research Institute, Seattle, Washington, United States of America
Department of Medicine, Institute for Social Research, Veterans Affairs Center for Clinical Management Research, Institute for Healthcare Policy and Innovation, University of Michigan, Ann Arbor, Michigan, United States of America
IN YOUR COVERAGE PLEASE USE THIS URL TO PROVIDE ACCESS TO THE FREELY AVAILABLE PAPER: http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1002236