WORLDWIDE ALZHEIMER S AND DEMENTIA EPIDEMIC GROWS, INCLUDING UNDERESTIMATES OF PREVALENCE IN LOW AND MIDDLE INCOME COUNTRIES

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1 CONTACT: Alzheimer s Association media line: , media@alz.org AAIC 2014 press room, July 13-17: WORLDWIDE ALZHEIMER S AND DEMENTIA EPIDEMIC GROWS, INCLUDING UNDERESTIMATES OF PREVALENCE IN LOW AND MIDDLE INCOME COUNTRIES New data on fewer new cases in developed nations suggests possibility of prevention and risk reduction COPENHAGEN, July 15, 2014 While the global epidemic of Alzheimer s disease continues to grow, new data on lower incidence in the youngest old from developed countries in Europe and the United States suggest the possibility of reducing risk and/or preventing the disease, according to the results of several research studies announced at the Alzheimer s Association International Conference 2014 (AAIC 2014) in Copenhagen. Scientists suggest higher education levels and more aggressive treatment of cardiovascular disease may be key. Pointing in the other direction, researchers reported at AAIC 2014 that incidence and prevalence of Alzheimer s in developing countries such as Colombia, and large regions of Asia and Africa, may be severely underreported. They also raise questions about the effects of the growing incidence of obesity and diabetes in developed countries, both of which are associated with increased risk of cognitive decline and dementia. For clarity following are the definitions of prevalence and incidence: Prevalence the number or proportion of cases of a disease in a population. (i.e., How many people have Alzheimer s disease in the U.S. right now?) Incidence the number of new cases of a disease in a population over a given time. (i.e., How many new cases of Alzheimer s are there this year in Denmark?) The good news is that recent trends in developed countries in Europe and the U.S. suggest that reduction and possibly even prevention of Alzheimer s disease might be possible but, at the same time, we must acknowledge the growing worldwide epidemic, said Maria Carrillo, Ph.D., Alzheimer s Association vice president of Medical and Scientific Relations. We must continue efforts to halt this terrible scourge that devastates families and economies. According to new data reported at AAIC 2014, Alzheimer s and dementia incidence and prevalence in developing countries may be much higher than previously thought, and rising rates of obesity and diabetes pose an unknown but potentially serious threat to cognitive health throughout the world. Many questions remain, and the only way we can get the answers is through more research, Carrillo said. There are hints in the literature that engaging in more challenging mental activities, such as higher levels of education or intellectually demanding occupations, may increase cognitive reserve and thereby reduce the risk of developing Alzheimer s or another dementia.

2 With the support of the Alzheimer s Association and the Alzheimer s community, the United States created its first National Plan to Address Alzheimer s Disease in The plan includes the critical goal, which was adopted by the G8 at the Dementia Summit in 2013, of preventing and effectively treating Alzheimer s by It is only through strong implementation and adequate funding of the plan, including an additional $200 million in fiscal year 2015 for Alzheimer's research, that we ll meet that goal. For more information and to get involved, visit Review of Recent Data Suggests Fewer New Cases of Alzheimer s in the United States and Europe Worldwide prevalence of Alzheimer s disease is projected to increase in the decades ahead as the planet s population ages, but recently published studies from the United States, the Netherlands, Sweden, and England suggest a decline in incidence or prevalence of dementia (or both) in those countries, according to a review of recent research conducted by Kenneth Langa, M.D., Ph.D., of the University of Michigan and the VA Ann Arbor Center for Clinical Management Research, and reported at a plenary session at AAIC Langa observed from the studies that a number of factors, especially rising levels of education and more aggressive treatment of cardiovascular risk factors such as hypertension and high cholesterol, may be leading to improved brain health and consequent decline of numbers of new cases of Alzheimer s disease and dementia in certain countries or regions of the world. Whether this trend will continue in the face of rising levels of obesity and diabetes, and whether it is also true in low- and middle-income countries, are key unanswered questions, said Langa. The answers will have enormous implications for the extent of the future worldwide impact of Alzheimer s disease and dementia in the decades ahead. Extent of Dementia in Asia and Sub-Saharan Africa May Be Severely Underestimated In 2009, Alzheimer s Disease International (ADI) published data on global prevalence of dementia based on a review of 154 worldwide studies and United Nations (U.N.) population projections. ADI carried out an update on that data for the December 2013 G8 Dementia Summit in London, focusing primarily on new evidence from Asia and Sub-Saharan Africa, and presented the results at AAIC Based on a meta-analysis of Chinese and Sub-Saharan African studies combined with the latest U.N. population projections, ADI concluded that the 2009 estimates of worldwide Alzheimer s disease were too low. ADI now estimates that million people in the world were living with dementia in 2013, significantly up from the earlier estimate of 36 million people living with dementia in They project that the number will rise to million in percent higher than the 2009 estimate and million in 2050, which is 17 percent higher than the 2009 ADI estimate. Specifically in the two focus regions, the researchers found that dementia prevalence increased for East Asia from about 5 percent to about 7 percent, and in Sub-Saharan African regions from a range of roughly 2 to 4 percent to 4.76 percent. Dementia, including Alzheimer s disease, is one of the biggest global health challenges facing our generation, said Marc Wortmann, executive director, Alzheimer s Disease International. As more and better data becomes available, the effect we ve seen is a reduction in the variation of prevalence between world regions. In addition, newly available data suggests that the current burden and future impact of the global dementia epidemic has been underestimated, particularly for the Asia and Sub-Saharan Africa. Especially in light of these revised estimates, there is an urgent need to develop policies to face this disease in all countries of the world, and to enhance our efforts in finding a cure or treatment that can delay the onset of dementia, Wortmann added. 2

3 New Cases of Dementia Decline Over Three Decades in the Framingham Heart Study At AAIC 2014, Claudia L. Satizabal, Ph.D. of Boston University School of Medicine and colleagues reported on the results of a study of dementia trends among participants in the Framingham Heart Study, an ongoing, long-term (since 1948), multi-generational cardiovascular health study of residents of Framingham, Massachusetts, to which dementia tracking has been added since Framingham Study participants undergo comprehensive assessments for cardiovascular risk factors every two to four years, and remain under intensive surveillance for dementia and stroke. Study researchers defined four non-overlapping five-year time windows (epochs) across the past three decades, each beginning with a baseline examination, and studied new cases of dementia among all dementia-free participants age 60 and older. After adjusting for age at entry and gender, the researchers found that compared with the first epoch, the second epoch had a 22 percent reduction in new cases of dementia, the third had a 38 percent reduction, and the fourth had a 44 percent reduction. The reduction was strongest in participants between age 60 and 69. The researchers found the decrease in dementia incidence was greatest in women across all epochs, while men showed a more gradual decrease over time. The decreasing trend in dementia incidence was true for individuals with a higher educational level, defined as having a high school diploma, whereas individuals without a high school diploma did not appear to benefit from this reduction. During that 30-year time period, the researchers observed among the participants a substantial improvement in educational achievement, better management of blood pressure, higher levels of HDL cholesterol, and a considerable decline in smoking, heart disease and stroke across the same epochs. However, an increasing trend in obesity and diabetes was seen in this population. These reductions in age-specific rates of new cases of dementia in the Framingham Study participants might be partly explained by the beneficial trends we observed in educational attainment and heart health risk factors, said Satizabal. This leads us to cautious optimism that some cases of dementia may be preventable. However, one of the limitations of this work is that the Framingham sample is largely of European descent. Additional studies are needed in populations of different racial and ethnic backgrounds. In Colombia, Dementia and Alzheimer s Disease Might Be Underestimated by Up to 50 Percent To date, Colombia has had only one study, known as EPINEURO, which attempted to estimate the country s dementia prevalence from representative samples of the population 20 years ago. Using updated population estimates and prevalence estimates published in the international literature, Yuri Takeuchi, M.D. of Universidad Icesi (Colombia) and colleagues estimated the number of people with dementia, and especially Alzheimer s disease, in Colombia by stage of the disease. The results were reported at AAIC The researchers created three models for Alzheimer s prevalence in the country, each using different projections for the proportion of people with mild, moderate, and severe disease, and different theoretical assumptions on the transitions between stages. They found that the number of people with Alzheimer s in Colombia could be as much as 220,000 in 2015, and 260,000 in The scientists calculate that current estimates for Alzheimer s disease and other dementias in Colombia might be too low by as much as 50 percent. (The prevalence estimate of dementia for Colombia in people over 65 used in the study was 6 percent, according to Takeuchi.) To our knowledge, this is the first attempt to model and estimate dementia prevalence by stage of disease in the developing world; it is certainly the first attempt in Colombia, said Takeuchi. The fastest growth in aging is happening in developing countries such as Colombia. This has profound implications not only for older people themselves, but for their households, social and community infrastructure, and social policy. These estimations by stage of disease are key information for policymakers because both the social burden and social costs are substantially different depending on the stage of disease. 3

4 Dementia in Germany Declined between 2007 and 2009 Gabriele Doblhammer, Ph.D. of the German Center for Neurodegenerative Diseases (DZNE) and colleagues conducted a study exploring short-term dementia trends in Germany, and reported the results at AAIC The research is based on claims data from the largest public health insurance company in Germany which covers about one-third of the total population aged 50+ and more than half of the oldest-old. The data include complete records of the inpatient and outpatient services, including dementia diagnosis. The complete insured population of roughly 5 million people at risk of dementia and about 600,000 dementia cases was used to study the prevalence; a 2.5 percent sample was the basis for the incidence study. The researchers found that between 2007 and 2009, the total number of people with dementia decreased significantly among German women age 74 to 85. Dementia prevalence in 2009 was 3.6 percent lower than in 2007 and 1.8 percent lower than in Over that period, new cases of dementia decreased significantly for both men and women. According to the researchers, over the last decade there was reduction in new cases of cerebrovascular disease in Germany and a better treatment of vascular risk factors such as high blood pressure, hypercholesterolemia, and diabetes mellitus. Among the elderly, increasing levels of education and wealth also were observed. This was the first study to explore dementia trends in Germany, said Doblhammer. The ageing of the babyboomers and the increasing life expectancy will lead to more dementia cases in old age. It is necessary to explore the modifiable risk factors of dementia in order to prevent the occurrence of the disease. In addition, more research is needed whether the increasing obesity epidemic and related diseases, such as the metabolic syndrome, may counterbalance the positive trends we are observing today. About AAIC The Alzheimer s Association International Conference (AAIC) is the world s largest gathering of leading researchers from around the world focused on Alzheimer s and other dementias. As a part of the Alzheimer s Association s research program, AAIC serves as a catalyst for generating new knowledge about dementia and fostering a vital, collegial research community. Scientists leading the advancement of research gather to report and discuss the most current data on the cause, diagnosis, treatment and prevention of Alzheimer s disease and related disorders. About the Alzheimer s Association The Alzheimer s Association is the world s leading voluntary health organization in Alzheimer care, support and research. Our mission is to eliminate Alzheimer s disease through the advancement of research; to provide and enhance care and support for all affected; and to reduce the risk of dementia through the promotion of brain health. Our vision is a world without Alzheimer s. Visit or call # # # EMBARGOED FOR RELEASE Kenneth Langa, University of Michigan and Ann Arbor VA. Is the Risk of Alzheimer's Disease Declining? A Review of Evidence From Around the World. (Funders: U.S. National Institute on Aging) Gabriele Doblhammer, German Center for Neurodegenerative Disease (DZNE), et al. Short-term Trends in German Dementia Prevalence, Incidence, and Mortality. (Funder: German Center for Neurodegenerative Disease) Claudia L. Satizabal, Boston University School of Medicine, Framingham Heart Study, et al. Temporal trends in Dementia Incidence in the Framingham Study. (Funder: U.S. National Institutes of Health) Yuri Takeuchi, Universidad Icesi, et al. Prevalence estimates of dementia in Colombia ( ). Transitions and stage of disease. (Funders: Universidad Icesi; Centro de Estudios en Protección Social y Economía de la Salud (PROESA), Cali - Colombia) Marc Wortmann, Alzheimer's Disease International. New global prevalence data on dementia. (Funder: Alzheimer's Disease International) 4

5 Proposal Number: Topic: Epidemiology Is the Risk of Alzheimer's Disease Declining?: A Review of Evidence From Around the World Presenting Author: Kenneth Langa, University of Michigan and Ann Arbor VA Background: The number of older adults with dementia will increase around the world in the decades ahead as populations age. Current estimates suggest that about 4.2 million adults in the United States have dementia and the attributable economic cost of their care is about US$200 billion per year. Worldwide dementia prevalence is estimated at 35.6 million people with a total cost of US$604 billion per year, and it is expected that worldwide prevalence will nearly triple to 115 million by However, a number of recent population-based studies from countries around the world suggest that the age-specific risk of dementia may be declining, which could help moderate the expected increase in dementia cases that will accompany the growing number of older adults. Methods: This presentation will review the current published evidence on the prevalence and economic costs of dementia in countries around the world, and whether the age-specific risk of Alzheimer's disease and dementia has declined over the past twenty years. Results: At least 5 recent population-based studies of dementia incidence or prevalence have shown a declining age-specific risk in the United States, Rotterdam, Stockholm, and England. A number of factors, especially rising levels of education and more aggressive treatment of key cardiovascular risk factors such as hypertension and hypercholesterolemia, may be leading to improving "brain health" and declining agespecific risk of AD and dementia in countries around the world. Conclusions: Whether this optimistic trend of declining dementia risk will continue in the face of rising levels of obesity and diabetes, and whether this trend is also occurring in low- and middle-income countries are key unanswered questions which will have enormous implications for the extent of the future world-wide impact of AD and dementia on patients, families, and societies in the decades ahead. 5

6 Proposal Number: Topic: Health Economics and Policy Short-term Trends in German Dementia Prevalence, Incidence, and Mortality Author Block: Gabriele Doblhammer, German Center for Neurodegenerative Diseases (DZNE); Anne Fink, German Center for Neurodegenerative Diseases; Stephanie Zylla, University of Rostock; Thomas Fritze, German Center for Neurodegenerative Diseases (DZNE); Frans Willekens, Max Planck Institute for Demographic Research; Presenting author Background: Recent studies have been cautiously optimistic about declining trends in dementia prevalence and incidence. This study explored short-terms trends in dementia prevalence, incidence and mortality in Germany using health claims data. We hypothesized that the period prevalence of dementia has been declining while the incidence of dementia has been shifting to higher ages. Methods: We used claims data of the largest public health insurance company in Germany. The data contained complete inpatient and outpatient diagnoses according to ICD-10. For the analysis of prevalence we used 6.5 million persons and 600,000 dementia cases for each of the years 2007, 2008, and 2009 applying negative binomial regression models. For the analysis of incidence and mortality two independent age-stratified samples of all insured persons aged 65 were taken. The first sample consisted of 139,617 persons in 2004 with a follow- up until 2007; the second sample of 134,653 persons in 2007 with a follow-up until Dementia was defined by the ICD numbers G30, G31.0, G31.82, G23.1, F00, F01, F02, F03, and F05.1. We estimated Cox- proportional hazard models to compare the incidence of dementia and the mortality of dementia patients between the two samples. Results: Over the period of 2007 to 2009, the prevalence of dementia decreased significantly among German women at ages 74 to 85. Compared to 2009, the prevalence was 3.6 per cent higher in 2007 (p=0.001) and 1.8 per cent higher in 2008 (p=0.019). A similar, albeit statistically not significant trend, was found for males of the same age. Also incidence decreased in the more recent sample: for females the relative risk (RR) of dementia in the 2004 sample was 1.25 (p=0.000) as compared to the most recent 2007 sample. For males it was 1.23 (p=0.000). Mortality of dementia patients increased significantly among women (RR 2004 as compared to 2007: 0.90; p=0.000), while it remained stable among men (RR 2004 as compared to 2007: 0.99; p=0.746). Conclusions: This is the first study that explored trends in dementia in Germany. The decline observed in this study, both in dementia prevalence and incidence, is of major consequences for the number of future dementia cases. 6

7 Proposal Number: Topic: Epidemiology Temporal trends in Dementia Incidence in the Framingham Study Author Block: Claudia L. Satizabal, Boston University School of Medicine, Framingham Heart Study; Alexa Beiser, Boston University Schools of Medicine and Public Health, Framingham Heart Study; Geneviève Chêne, Inserm U897 and CIC-EC7; University of Bordeaux, Isped (Bordeaux School of Public Health); Vincent A. Chouraki, Boston University School of Medicine, Framingham Heart Study; Jayandra J. Himali, Boston University School of Medicine, Framingham Heart Study; Sarah R. Preis, Boston University School of Public Health, Framingham Heart Study; Sanford Auerbach, Boston University School of Medicine, Framingham Heart Study; Rhoda Au, Framingham Heart Study/Boston University; Philip A. Wolf, Boston University School of Medicine, Framingham Heart Study; Carole Dufouil, INSERM U708 & CIC-EC7, University of Bordeaux, Isped (Bordeaux School of Public Health); Sudha Seshadri, Boston University School of Medicine, Framingham Heart Study; Presenting author Background: Recent studies from Europe suggest age-specific dementia incidence is declining, although the overall burden of dementia grows as life-expectancy increases. This has been attributed to an improved control of vascular risk factors. However, a large US study observed no decline in dementia incidence despite a lower risk of cognitive impairment. We studied temporal trends in dementia incidence over three decades among Framingham Study participants. Methods: Framingham participants periodically undergo comprehensive assessments for risk factors once every 2-4 years, and remain under intensive surveillance for incident disease including dementia and stroke. We defined four epochs across the past three decades, each anchored at a baseline examination, and studied 5-year dementia incidence among all dementia-free participants aged 60 years who attended that examination. We examined the baseline prevalence of vascular risk factors and calculated dementia incidence in each epoch. Age- and sex-adjusted Cox proportional-hazard models were used to compare the incidence across epochs. In secondary analyses, we examined both whether these trends differed within age, gender and education categories, and the impact of additional adjustment for interim stroke. Results: Compared to the first epoch, there were 17%, 32% and 42% reductions in dementia incidence in the second, third and fourth epochs respectively. Additional adjustment for stroke did not modify our results. This reduction was strongest in younger participants (60-69 years) and in the last epoch for all age categories. Reductions in dementia incidence were similar for women and men in the last epoch. Interestingly, participants with at least high school education had a consistent reduction in dementia incidence across all time-periods, while those less educated did not. We observed significant improvements in educational status, use of antihypertensive and statin medication, blood pressure and HDL levels and in prevalence of smoking, heart disease and stroke, whereas prevalence of obesity and diabetes increased. Conclusions: In the last three decades, age-specific incidence rates of dementia have declined in the Framingham cohort. These reductions might be partly explained by beneficial trends in educational attainment, vascular risk factors (acting only partly through clinical stroke) and lifestyle, leading to cautious optimism that some dementia may be preventable. 7

8 Proposal Number: Topic: Health Economics and Policy PREVALENCE ESTIMATES OF DEMENTIA IN COLOMBIA ( ). TRANSITIONS AND STAGE OF DISEASE Author Block: Yuri Takeuchi, Universidad Icesi; Yoseth Ariza-Araujo, Universidad Icesi; Sergio Prada, Universidad Icesi; Presenting author Background: The only study involving a nationally representative sample to estimate dementia prevalence in Colombia has been the EPINEURO. This was a population-based survey of a stratified random sample of urban and rural residents of five regions of Colombia. The purpose of this paper was to estimate the number of people suffering from dementia and in particular Alzheimer s disease (AD) in Colombia by severity stage. Methods: Using secondary data, updated population estimations and a cohort component population projection method we estimated the number of patients with AD by stage in Colombia. The model rests on three basic elements: prevalence, incidence and mortality rates by disease s stage. We estimated three scenarios. The first one is the baseline in which we applied to the population projection prevalence rates by gender, adjusted dementia cases by 70% to get AD cases and distributed patients annually using the following criteria: 48% mild, 31% moderate, and 21% severe. In this baseline model there is no transition between stages. The second and third scenarios modeled transition dynamic between stages. Results: The number of people with AD could be approximately in 2015, and in We estimated three scenarios to investigate what could be the distribution of the population with the disease by stage. Depending on the assumptions made regarding the stage at which new cases are identified, the share of those in the moderate stage could be up to 20 percentage points higher than a baseline model with fixed proportions. The current estimates in the published literature could be underestimating the number of people with dementias and AD by 50%. Conclusions: The fastest growth in aging is happening in developing countries with profound implications not only for the older people themselves, but for their households, the social and community infrastructure and for social policy. Developing societies, as Colombia, are now faced with an ageing population and a more generous coverage of healthcare needs. Since the services required by patients are differential according to the stage and disease involvement, research involving stage distribution to estimate burden of the disease and costs are required. 8

9 Proposal Number: Topic: Health Economics and Policy New global prevalence data on dementia Author Block: Marc Wortmann, Alzheimer's Disease International Presenting author Background: Alzheimer's Disease International (ADI) published global prevalence data on dementia in the World Alzheimer Report 2009 based on a systematic review of 154 studies conducted worldwide, and United Nations population projections through to the year We estimated 36 million people with dementia in 2010, nearly doubling every 20 years to 66 million by 2030 and to 115 million by 2050.The G8 Dementia Summit on 11 December 2013 in London provided an opportunity to update evidence on the scale and the distribution of the global dementia epidemic. Methods: For the current update, we carried out a limited review, focusing on the new evidence emerging from China and the sub-saharan African regions, and applied the new prevalence proportions to the latest (2012) UN population projections. Results: The prevalence of dementia estimated from the recent review and meta-analysis of China studies and meta-analysis of studies from sub-saharan Africa were substantially higher than those used in the 2009 World Alzheimer Report. Age-standardised prevalence for East Asia increased from 4.98% to 6.99% and in the sub- Saharan African regions from a range of 2.07% to 4.00%, to 4.76% The net effect, as more data becomes available, is a further reduction in the variation of prevalence between world regions. The number of people living with dementia worldwide in 2013 is estimated at million, reaching million in 2030 and million in The updated estimates are higher than our original estimates reported in the 2009 World Alzheimer Report, by 15% in 2030, and by 17% in Conclusions: Dementia, including Alzheimer's disease, is one of the biggest global public health challenges facing our generation. Newly available data suggests that the current burden and future impact of the dementia epidemic has been underestimated, particularly for the Asia East and Sub-Saharan African regions. There is an urgent need to develop policies to face this disease in all countries of the world and to enhance our efforts in finding a cure or treatment that can at least delay the onset of dementia. (end) 9