Alzheimer's disease epidemiology and demographics
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
|
Alzheimer's disease Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Alzheimer's disease epidemiology and demographics On the Web |
|
American Roentgen Ray Society Images of Alzheimer's disease epidemiology and demographics |
|
Alzheimer's disease epidemiology and demographics in the news |
|
Risk calculators and risk factors for Alzheimer's disease epidemiology and demographics |
Overview
Alzheimer's disease is the most frequently seen form of dementia, and it typically develops in elderly patients.
Epidemiology
Alzheimer's disease is the most frequent type of dementia in the elderly and affects almost half of all patients with dementia. Correspondingly, advancing age is the primary risk factor for the disease. [1] [2] An estimated 35 million people worldwide have Alzheimer's disease.
Prevalence
Two main measures are used in epidemiological studies: incidence and prevalence. Incidence is the number of new cases per unit of person–time at risk (usually number of new cases per thousand person–years); while prevalence is the total number of cases of the disease in the population at a given time.
Prevalence of AD in populations is dependent upon different factors including incidence and survival. Since the incidence of AD increases with age, it is particularly important to include the mean age of the population of interest. In the United States, Alzheimer prevalence was estimated to be 1.6% in the year 2000 both overall and in the 65–74 age group, with the rate increasing to 19% in the 75–84 group and to 42% in the greater than 84 group.[3] Prevalence rates in less developed regions are lower.[4] The World Health Organization estimated that in 2005, 0.379% of people worldwide had dementia, and that the prevalence would increase to 0.441% in 2015 and to 0.556% in 2030.[5] Other studies have reached similar conclusions.[4] Another study estimated that in 2006, 0.40% of the world population (range 0.17–0.89%; absolute number 26.6 million, range 11.4–59.4 million) were afflicted by AD, and that the prevalence rate would triple and the absolute number would quadruple by the year 2050.[6]
Age
Generally it is diagnosed in people over 65 years of age,[7] although the less-prevalent early-onset Alzheimer's can occur much earlier.
| Age | Incidence (new affected) per thousand person–years |
|---|---|
| 65–69 | 3 |
| 70–74 | 6 |
| 75–79 | 9 |
| 80–84 | 23 |
| 85–89 | 40 |
| 90– | 69 |
References
- ↑ Gorelick P (2004). "Risk factors for vascular dementia and Alzheimer disease". Stroke. 35 (11 Suppl 1): 2620–2622. doi:10.1161/01.STR.0000143318.70292.47. PMID 15375299.
- ↑ Hebert L, Scherr P, Bienias J, Bennett D, Evans D (2003). "Alzheimer disease in the U.S. population: prevalence estimates using the 2000 census". Archives of Neurology. 60 (8): 1119–1122. doi:10.1001/archneur.60.8.1119. PMID 12925369.
- ↑ 2000 U.S. estimates:
- Hebert LE, Scherr PA, Bienias JL, Bennett DA, Evans DA (2003). "Alzheimer disease in the US population: prevalence estimates using the 2000 census". Arch. Neurol. 60 (8): 1119–22. doi:10.1001/archneur.60.8.1119. PMID 12925369. Unknown parameter
|month=ignored (help) - "Profiles of general demographic characteristics, 2000 census of population and housing, United States" (PDF). U.S. Census Bureau. 2001. Retrieved 2008-08-27.
- Hebert LE, Scherr PA, Bienias JL, Bennett DA, Evans DA (2003). "Alzheimer disease in the US population: prevalence estimates using the 2000 census". Arch. Neurol. 60 (8): 1119–22. doi:10.1001/archneur.60.8.1119. PMID 12925369. Unknown parameter
- ↑ 4.0 4.1 Ferri CP, Prince M, Brayne C; et al. (2005). "Global prevalence of dementia: a Delphi consensus study" (PDF). Lancet. 366 (9503): 2112–7. doi:10.1016/S0140-6736(05)67889-0. PMID 16360788. Retrieved 2008-06-13. Unknown parameter
|month=ignored (help) - ↑ World Health Organization (2006). Neurological Disorders: Public Health Challenges. Switzerland: World Health Organization. pp. 204–207. ISBN 978-92-4-156336-9.
- ↑ 2006 prevalence estimate:
- Brookmeyer R, Johnson E, Ziegler-Graham K, MH Arrighi (2007). "Forecasting the global burden of Alzheimer's disease". Alzheimer's and Dementia. 3 (3): 186–91. doi:10.1016/j.jalz.2007.04.381. Retrieved 2008-06-18. Unknown parameter
|month=ignored (help) - Template:Cite paper
- Brookmeyer R, Johnson E, Ziegler-Graham K, MH Arrighi (2007). "Forecasting the global burden of Alzheimer's disease". Alzheimer's and Dementia. 3 (3): 186–91. doi:10.1016/j.jalz.2007.04.381. Retrieved 2008-06-18. Unknown parameter
- ↑ Brookmeyer R, Gray S, Kawas C (1998). "Projections of Alzheimer's disease in the United States and the public health impact of delaying disease onset". Am J Public Health. 88 (9): 1337–42. PMC 1509089. PMID 9736873. Unknown parameter
|month=ignored (help) - ↑ Bermejo-Pareja F, Benito-León J, Vega S, Medrano MJ, Román GC (2008). "Incidence and subtypes of dementia in three elderly populations of central Spain". Journal of the Neurological Sciences. 264 (1–2): 63–72. doi:10.1016/j.jns.2007.07.021. PMID 17727890. Retrieved 2012-08-15. Unknown parameter
|month=ignored (help)