Global, regional, and national burden of Alzheimer's disease and other dementias, 1990–2016: a systematic analysis for the Global Burden of Disease Study 2016
Authors: Emma Nichols, Cassandra E I Szoeke, Stein Emil Vollset, Nooshin Abbasi, Foad Abd-Allah, Jemal Abdela, Miloud Taki Eddine Aichour, Rufus O Akinyemi, Fares Alahdab, Solomon W Asgedom, Ashish Awasthi, Suzanne L Barker-Collo, Bernhard T Baune, Yannick Béjot, Abate B Belachew, Derrick A. Bennett, Belete Biadgo, Ali Bijani, Muhammad Shahdaat Bin Sayeed, Carol Brayne, David O Carpenter, Félix Carvalho, Ferrán Catalá-López, Ester Cerin, Jee-Young J Choi, Anh Kim Dang, Meaza G Degefa, Shirin Djalalinia, Manisha Dubey, Eyasu Ejeta Duken, David Edvardsson, Matthias Endres, Sharareh Eskandarieh, Andre Faro, Farshad Farzadfar, Seyed-Mohammad Fereshtehnejad, Eduarda Fernandes, Irina Filip, Florian Fischer, Abadi K Gebre, Demeke Geremew, Maryam Ghasemi-Kasman, Elena V. Gnedovskaya, Rajeev Gupta, Vladimir Hachinski, Tekleberhan B Hagos, Samer Hamidi, Graeme J. Hankey, Josep M Haro, Simon I Hay, Seyed Sina N Irvani, Ravi P Jha, Jost B. Jonas, Rizwan Kalani, André Karch, Amir Kasaeian, Yousef Saleh Khader, Ibrahim A Khalil, Ejaz Ahmad Khan, Tripti Khanna, Tawfik A M Khoja, Jagdish Khubchandani, Adnan Kisa, Katarzyna Kissimova-Skarbek, Mika Kivimäki, Ai Koyanagi, Kristopher J Krohn, Giancarlo Logroscino, Stefan Lorkowski, Marek Majdan, Reza Malekzadeh, Winfried März, João Massano, Getnet Mengistu, Atte Meretoja, Moslem Mohammadi, Maryam Mohammadi-Khanaposhtani, Ali H Mokdad, Stefania Mondello, Ghobad Moradi, Gabriele Nagel, Mohsen Naghavi, Gurudatta Naik, Long H Nguyen, Trang H Nguyen, Yirga L Nirayo, Molly R Nixon, Richard Ofori-Asenso, Felix A Ogbo, Andrew T Olagunju, Mayowa O Owolabi, Songhomitra Panda-Jonas, Valéria M de Azeredo Passos, David M. Pereira, Gabriel D Pinilla-Monsalve, Michael A Piradov, Constance D Pond, Hossein Poustchi, Mostafa Qorbani, Amir Radfar, Robert C Reiner, Stephen R Robinson, Gholamreza Roshandel, Ali Rostami, Tom C Russ, Perminder S Sachdev, Hosein Safari, Saeid Safiri, Ramesh Sahathevan, Yahya Salimi, Maheswar Satpathy, Monika Sawhney, Mete Saylan, Sadaf G. Sepanlou, Azadeh Shafieesabet, Masood A Shaikh, Mohammad Ali Sahraian, Mika Shigematsu, Rahman Shiri, Ivy Shiue, João P Silva, Mari Smith, Soheila Sobhani, Dan J Stein, Rafael Tabarés-Seisdedos, Marcos R Tovani-Palone, Bach X Tran, Tung Thanh Tran, Amanuel T Tsegay, Irfan Ullah, Narayanaswamy Venketasubramanian, Vasily Vlassov, Yuan-Pang Wang, Jordan Weiss, Ronny Westerman, Tissa Wijeratne, Grant M.A. Wyper, Yuichiro Yano, Ebrahim M Yimer, Naohiro Yonemoto, Mahmoud Yousefifard, Zoubida Zaidi, Zohreh Zare, Theo Vos, Valery L. Feigin, Christopher J L Murray
Journal: The Lancet Neurology (2018)

BackgroundThe number of individuals living with dementia is increasing, negatively affecting families, communities, and health-care systems around the world. A successful response to these challenges requires an accurate understanding of the dementia disease burden. We aimed to present the first detailed analysis of the global prevalence, mortality, and overall burden of dementia as captured by the Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study 2016, and highlight the most important messages for clinicians and neurologists.MethodsGBD 2016 obtained data on dementia from vital registration systems, published scientific literature and surveys, and data from health-service encounters on deaths, excess mortality, prevalence, and incidence from 195 countries and territories from 1990 to 2016, through systematic review and additional data-seeking efforts. To correct for differences in cause of death coding across time and locations, we modelled mortality due to dementia using prevalence data and estimates of excess mortality derived from countries that were most likely to code deaths to dementia relative to prevalence. Data were analysed by standardised methods to estimate deaths, prevalence, years of life lost (YLLs), years of life lived with disability (YLDs), and disability-adjusted life-years (DALYs; computed as the sum of YLLs and YLDs), and the fractions of these metrics that were attributable to four risk factors that met GBD criteria for assessment (high body-mass index [BMI], high fasting plasma glucose, smoking, and a diet high in sugar-sweetened beverages).FindingsIn 2016, the global number of individuals who lived with dementia was 43·8 million (95% uncertainty interval [UI] 37·8–51·0), increased from 20.2 million (17·4–23·5) in 1990. This increase of 117% (95% UI 114–121) contrasted with a minor increase in age-standardised prevalence of 1·7% (1·0–2·4), from 701 cases (95% UI 602–815) per 100 000 population in 1990 to 712 cases (614–828) per 100 000 population in 2016. More women than men had dementia in 2016 (27·0 million, 95% UI 23·3–31·4, vs 16.8 million, 14.4–19.6), and dementia was the fifth leading cause of death globally, accounting for 2·4 million (95% UI 2·1–2·8) deaths. Overall, 28·8 million (95% UI 24·5–34·0) DALYs were attributed to dementia; 6·4 million (95% UI 3·4–10·5) of these could be attributed to the modifiable GBD risk factors of high BMI, high fasting plasma glucose, smoking, and a high intake of sugar-sweetened beverages.InterpretationThe global number of people living with dementia more than doubled from 1990 to 2016, mainly due to increases in population ageing and growth. Although differences in coding for causes of death and the heterogeneity in case-ascertainment methods constitute major challenges to the estimation of the burden of dementia, future analyses should improve on the methods for the correction of these biases. Until breakthroughs are made in prevention or curative treatment, dementia will constitute an increasing challenge to health-care systems worldwide.FundingBill & Melinda Gates Foundation.