Co-Principal Investigators: Claudia Kawas, MDMaria Corrada, ScD
Co-Investigators: Annlia Paganini-Hill, PhD; Dana Greenia, RN, MS

Grandmother Reading with Granddaughter --- Image by © Royalty-Free/Corbis

The 90+ Study was initiated in 2003 to study the oldest-old, the fastest growing age group in the United States.  The 90+ Study is one of the largest studies of the oldest-old in the world. More than 1,600 people have enrolled.  Because little is known about people who achieve this milestone, the remarkable increase in the number of oldest-old presents a public health priority to promote the quality as well as the quantity of life.

The 90+ Study participants

Initial participants in The 90+ Study were once members of The Leisure World Cohort Study (LWCS), which was started in 1981.  The LWCS mailed surveys to every resident of Leisure World, a large retirement community in Orange County, California (now incorporated as the city of Laguna Woods).  Using the 14,000 subjects from the LWCS, researchers from The 90+ Study were able to ask, What allows people to live to age 90 and beyond?

Studying the oldest-old

Participants of The 90+ Study are visited every six months by researchers who perform neurological and neuropsychological tests. Our researchers at the Clinic for Aging Research and Education (CARE), located in Laguna Woods, obtain information about diet, activities, medical history, medications and numerous other factors. Additionally, participants are given a series of cognitive and physical tests to determine how well people in this age group are functioning.

Goals of the study
  • Determine factors associated with longevity:  What makes people live to age 90 and beyond?  What types of food, activities or lifestyles are associated with living longer?
  • Examine the epidemiology of dementia in the oldest-old: How many people aged 90 and older have dementia?  How many become demented each year?  What are ways to remain dementia-free into your 90s?
  • Examine rates of cognitive and functional decline in the oldest-old: How do memory loss and disability affect those in their 90s?  How can people prevent memory loss and disability at this age?
  • Examine clinical pathological correlations in the oldest-old:  Do the brains of people in their 90s show evidence of memory loss and dementia?  Do people with dementia have differences in their brains that can be detected and treated?  Determining Modifiable Risk Factors for Mortality and Dementia: What kinds of things can people change in their lives to live longer?  Can people change their risk of dementia through diet, exercise or supplements?
Major findings

Researchers from The 90+ Study have published many scientific papers in premier journals.  Some of the major findings are:

  • People who drank moderate amounts of alcohol or coffee lived longer than those who abstained.
  • People who were overweight in their 70s lived longer than normal or underweight people did.
  • Over 40% of people aged 90 and older suffer from dementia while almost 80% are disabled. Both are more common in women than men.
  • About half of people with dementia over age 90 do not have sufficient neuropathology in their brain to explain their cognitive loss.
  • People aged 90 and older with an APOE2 gene are less likely to have clinical Alzheimer’s dementia, but are much more likely to have Alzheimer’s neuropathology in their brains.

The 90+ Study is seeking new participants. If you are at least 90 years old and are willing to participate in twice annual visits and donate your brain to research after death, you may be eligible to enroll in The 90+ Study.

Please contact 949.768.3635 or for more information.

The 90+ Study Team

Co-Principal Investigators

Claudia Kawas, M.D.

Maria Corrada, Sc.D


Annlia Paganini-Hill, Ph.D

S. Ahmad Sajjadi, M.D., Ph.D

Dana Greenia, RN, MS

Neurological Examiners

Farah Mozaffar, M.D.

Neuropsychological Testers

Colette Aguirre, BA

Christina Whittle, BS

Jaime Demoss, BA

Zarui A. Melikyan, Ph.D

Study Coordination/Administration

Montez Hester, BS

Sara Ashrafnia, BS

Maria Kirkwood

Maria Kirkwood

Data Management/Statistical Analysis

Natalie Bryant, BS

Blinda Li, MS


Sara Sabeti

Zeinah Al-darsani

Tim Lee


Prevalence of Frailty and Factors Associated with Frailty in Individuals Aged 90 and Older: The 90+ Study. Lee DR, Kawas CH, Gibbs L, Corrada MM. J Am Geriatr Soc. 2016 Nov;64(11):2257-2262. PMID: 27590837.

Microinfarcts are common and strongly related to dementia in the oldest-old: The 90+ study. Corrada MM, Sonnen JA, Kim RC, Kawas CH. Alzheimers Dement. 2016 Aug;12(8):900-8. PMID: 27243907.

Sound Body Sound Mind? Physical Performance and the Risk of Dementia in the Oldest-Old: The 90+ Study. Bullain SS, Corrada MM, Perry SM, Kawas CH. J Am Geriatr Soc.  2016 Jul;64(7):1408-15. PMID: 27377238.

Impact of interventions to reduce Alzheimer’s disease pathology on the prevalence of dementia in the oldest-old. Brookmeyer R, Kawas CH, Abdallah N, Paganini-Hill A, Kim RC, Corrada MM. Alzheimers Dement. 2016 Mar;12(3):225-32. PMID: 26900132.

Synaptic Aβ oligomers precede p‐tau and differentiate high pathology control cases. Bilousova T, Miller CA, Poon WW, Vinters HV, Corrada MM, Kawas CH, Hayden EY, Teplow DB, Glabe C, Albay R 3rd, Cole GM, Teng E, Gylys KH. Am J Pathol. 2016 Jan; 186(1):185‐198. PMID: 26718979.


Brain‐derived neurotrophic factor and TrkB expression in the “oldest‐old,” the 90+Study: correlation with cognitive status and levels of soluble amyloid‐beta. Michalski B, Corrada MM, Kawas CH, Fahnestock M. Neurobiol Aging. 2015 Dec.; 36(12):3130‐3139. PMID: 26410307.

Multiple pathologies are common and related to dementia in the oldest-old: The 90+ Study. Kawas CH, Kim RC, Sonnen JA, Bullain SS, Trieu T, Corrada MM. Neurology. 2015 Jul 15. PMID:26180144.

Lifestyle Factors and Dementia in the Oldest-old: The 90+ Study. Paganini-Hill A, Kawas CH, Corrada MM. Alzheimer Dis Assoc Disord. 2015 Mar 6. PMID:25710250.

Antioxidant vitamin intake and mortality: the Leisure World Cohort Study. Paganini-Hill A, Kawas CH, Corrada MM. Am J Epidemiol. 2015 Jan 15;181(2):120-6. PMID:25550360.


Intracellular amyloid and the neuronal origin of Alzheimer neuritic plaques. Pensalfini A, Albay R 3rd, Rasool S, Wu JW, Hatami A, Arai H, Margol L, Milton S, Poon WW, Corrada MM, Kawas CH, Glabe CG. Neurobiol Dis. 2014 Nov;71:53-61. doi: 10.1016/j.nbd.2014.07.011. Epub 2014 Aug 1. PMID:25092575.

ABCC9 gene polymorphism is associated with hippocampal sclerosis of aging pathology. Nelson PT, Estus S, Abner EL, Parikh I, Malik M, Neltner JH, Ighodaro E, Wang WX, Wilfred BR, Wang LS, Kukull WA, Nandakumar K, Farman ML, Poon WW, Corrada MM, Kawas CH, Cribbs DH, Bennett DA, Schneider JA, Larson EB, et al. Acta Neuropathol. 127(6):825-843, 2014. PMID: 24770881.

Exponential increases in the prevalence of disability in the oldest old: a Canadian national survey. Guay M, Dubois MF, Corrada M, Lapointe-Garant MP, Kawas C.  Gerontology. 60(5):395-401, 2014. PMID: 24818716.

Perforant path synaptic loss correlates with cognitive impairment and Alzheimer’s disease in the oldest-old. Robinson JL, Molina-Porcel L, Corrada MM, Raible K, Lee EB, Lee VM, Kawas CH, Trojanowski JQ.  Brain. 137(Pt 9):2578-2587, 2014. PMID: 25012223. PMCID: 4132652.

Intracellular amyloid and the neuronal origin of Alzheimer neuritic plaques. Pensalfini A, Albay R, 3rd, Rasool S, Wu JW, Hatami A, Arai H, Margol L, Milton S, Poon WW, Corrada MM, Kawas CH, Glabe CG.  Neurobiol Dis. 71C:53-61, 2014. PMID: 25092575.


Dementia in the oldest-oldBullain SS, Corrada MM.  Neurology Continuum (Minneap Minn) 19(2 Dementia):457-469, 2013. PMID: 23558489.

DRD4 genotype predicts longevity in mouse and human. Grady D, Thanos P, Corrada MM, Barnett J, Ciobanu V, Shustarovich D, Napoli A, Grandy D, Moyzis A, Rubinstein M, Wang G-J, Kawas C, Chen C, Dong Q, Wang E, Volkow N, Moyzis R. Journal of Neuroscience 33:286-291,2013. PMID: 23283341.

Responders Versus Nonresponders in a Dementia Study of the Oldest Old: The 90+ Study. Paganini-Hill A, Ducey B, Hawk M. American Journal of Epidemiology. 2013 Apr 7. PMID: 23568592.

Amyloid imaging and cognitive decline in non-demented oldest-old: The 90+ Study. Kawas CH, Greenia DE, Bullain SS, Clark CM, Pontecorvo MJ, Joshi AD, Corrada MM.  Alzheimer’s & Dementia. 2013 Mar 9:199-203. [Epub 2012 Nov 1]. PMID: 23164550. PMCID: 3604036.

Neocortical b-amyloid area is associated with dementia and APOE in the oldest-old. Berlau DJ, Corrada MM, Robinson JL, Geser F, Arnold SE, Lee, VM-Y, Kawas CH, Trojanowski JQ. Alzheimer’s & Dementia. 2013 Mar 6: pii: S1552-5260. PMID: 23474043.

Aging in Place in a Retirement Community: 90+ Year Olds. Paganini-Hill A. J Hous Elderly. 2013 Jan 1;27(1-2):191-205. PMID: 25288828.

APOE genotype, dementia, and mortality in the oldest-old: The 90+ Study. Corrada MM, Paganini-Hill A, Berlau DJ, Kawas CH. Alzheimer’s & Dementia. 2013 Jan 9(1):12-8. [Epub 2012 Nov 2]. PMID: 23123227.

Poor Physical Performance and Dementia in the Oldest-Old: The 90+ Study. Bullain SS, Corrada MM, Shah BA, Mozaffar FH, Panzenboeck M, Kawas CH. JAMA Neurology. 2013 Jan 7(1):107-13. PMID: 23090391.


Hypertension and dementia in the elderly: the leisure world cohort study. Paganini-Hill A. Int J Hypertens. 2012;2012:205350. PMID: 22229084.

Alzheimer disease pathology and longitudinal cognitive performance in the oldest-old with no dementia. Balasubramanian AB, Kawas CH, Peltz CB et al.  Neurology. 2012 Aug 28;79:915-921. PMID: 22895581.

Cognitive impairment in non-demented oldest-old:  prevalence and relationship to cardiovascular risk factors. Peltz CB, Corrada MM, Berlau DJ, Kawas CH. Alzheimer’s & Dementia. 2012; 8(2):87-94. [Epub Nov 4, 2011]. PMID: 22055654. PMCID: 3276712.

A population-based clinicopathological study in the oldest-old: The 90+ Study. Corrada MM, Berlau DJ, Kawas CH. Curr Alzheimer Res. 2012;9:709-717. PMID: 22471863. PMCID: 3409303.

Disability in the Oldest-old: Incidence and Risk Factors in The 90+ Study. Berlau DJ, Corrada MM, Peltz CB, Kawas CH.  Am J Geriatr Psychiatry. 2012, 20:159-168. PMID: 22273736. PMCID: 3266513.


Neocortical and hippocampal amyloid-beta and tau measures associate with dementia in the oldest-old. Robinson JL, Geser F, Corrada MM, Berlau DJ, Arnold SE, Kawas CH, Lee VM, Trojanowski JQ.  Brain. 134(Pt 12):3705-3712, 2011. PMID: 22120149. PMCID: 3235569.

Lifestyle practices and cardiovascular disease mortality in the elderly: the Leisure World Cohort Study. Paganini-Hill A. Cardiol Res Pract. 2011;2011:983764.

Activities and mortality in the elderly: the Leisure World Cohort Study. Paganini-Hill A, Kawas CH, Corrada MM. J Gerontol A Biol Sci Med Sci. 2011;66:559-567. PubMedCentID: 3074957.

Incidence of dementia in oldest-old with amnestic MCI and other cognitive impairments. Peltz CB, Corrada MM, Berlau DJ, Kawas CH. Neurology. 2011; 77:1906-1912. PMID: 22076544. PMCID: 3233189

Bathing as a potential target for disability reduction in the oldest old. Berlau DJ, Corrada MM, Peltz CB, Kawas CH. Am J Public Health. 2011 Feb;101:200-201.

Diagnosing dementia in the oldest-old. Brumback-Peltz C, Balasubramanian AB, Corrada MM, Kawas CH. Maturitas. 2011 Oct;70:164-168. PubMedCentID: 3171568.


Being overweight in adults aged 70-75 is associated with a reduction in mortality risk compared with normal BMI. Corrada MM, Paganini-Hill A. Evid Based Med. 2010;15:126-127.

Dementia incidence continues to increase with age in the oldest-old: The 90+ Study. Corrada MM, Brookmeyer R, Paganini-Hill A, Berlau D, Kawas CH. Ann Neurol. 2010;67:114-121.

Abnormal EEGs in cognitively and physically healthy oldest old: findings from The 90+ Study. Peltz CB, Kim HL, Kawas CH. J Clin Neurophysiol. 2010;27:292-295.


High levels of serum C-reactive protein are associated with greater risk of all-cause mortality, but not dementia, in the oldest-old: Results from The 90+ Study. Kravitz BA, Corrada MM, Kawas CH. J Am Geriatr Soc. 2009;57:641-646.

The prevalence of disability in the oldest-old is high and continues to increase with age: findings from The 90+ Study. Berlau DJ, Corrada MM, Kawas CH. Int J Geriatr Psychiatry. 2009;24:1217-1225.

APOE epsilon2 is associated with intact cognition but increased Alzheimer pathology in the oldest old. Berlau DJ, Corrada MM, Head E, Kawas CH. Neurology. 2009;72:829-834.

Synaptic proteins, neuropathology and cognitive status in the oldest-old. Head E, Corrada MM, Kahle-Wrobleski K, Kim RC, Sarsoza F, Goodus M, Kawas CH. Neurobiol Aging. 2009;30:1125-1134.

Elevated C-reactive protein levels are associated with prevalent dementia in the oldest-old. Kravitz BA, Corrada MM, Kawas CH. Alzheimers Dement. 2009;5:318-323.


Prevalence of dementia after age 90: results from The 90+ Study. Corrada MM, Brookmeyer R, Berlau D, Paganini-Hill A, Kawas CH. Neurology. 2008;71:337-343.

The oldest old and The 90+ Study. Kawas CH. Alzheimers Dement. 2008;4:S56-59.


Sensitivity and specificity of the mini-mental state examination for identifying dementia in the oldest-old: The 90+ Study. Kahle-Wrobleski K, Corrada MM, Li B, Kawas CH. J Am Geriatr Soc. 2007;55:284-289.

Type of alcohol consumed, changes in intake over time and mortality: the Leisure World Cohort Study. Paganini-Hill A, Kawas CH, Corrada MM. Age Ageing. 2007;36:203-209.

Neuropsychological data in nondemented oldest-old: The 90+ Study. Whittle C, Corrada MM, Dick M, Ziegler R, Kahle-Wrobleski K, Paganini-Hill A, Kawas CH. J Clin Exp Neuropsychol. 2007;29:290-299.

Dissociation of neuropathologic findings and cognition: case report of an apolippoprotein E e2/e2 genotype. Berlau DJ, Kahle-Wrobleski K, Head E, M G, Kim R, Kawas CH. Arch Neurol. 2007;64:1193-1196.

Non-alcoholic beverage and caffeine consumption and mortality: the Leisure World Cohort Study. Paganini-Hill A, Kawas CH, Corrada MM. Prev Med. 2007;44:305-310.


Increased longevity in older users of postmenopausal estrogen therapy: the Leisure World Cohort Study. Paganini-Hill A, Corrada MM, Kawas CH. Menopause. 2006;13:12-18.

Association of body mass index and weight change with all-cause mortality in the elderly. Corrada MM, Kawas CH, Mozaffar F, Paganini-Hill A. Am J Epidemiol. 2006;163:938-949.

Alzheimer’s and dementia in the oldest-old: a century of challenges. Kawas CH, Corrada MM. Curr Alzheimer Res. 2006;3:411-419.


Computerized neuropsychiatric assessment of geriatric subjects by content analysis of brief samples of their speech. Gottschalk LA, Kawas CH, Hoang A, Bechtel RJ. Comput Inform Nurs. 2004;22:351-355.

Old News is Good News is the The 90+Study newsletter designed to keep you informed of our research progress.
  • 2014

  • We are excited to share a few of the articles that have been written about The 90+ Study throughout the course of our research since 2003

    Current News

    Late-age onset of high blood pressure may reduce risk of dementia, UCI study finds

    Los Angeles Times- January 2017 

    When the Pressure Is High the Dementia Is Low

    Sounds of Science Podcasts- January 2017

    Past News

    The 90+ Study was featured on the May 4th, 2014 broadcast of 60 Minutes with Leslie Stahl. You can watch the full episode with the link below.

    The 90+Study on CBS’s 60 Minutes 2014


    Run on the local Laguna Woods Village channel, Dr. Claudia Kawas discusses the 90+ Study and the study’s recently reopened recruitment


    Dr. Claudia Kawas also made an appearance on Fox’s Good Day LA to respond to the 60 Minutes episode after it aired.



    Every year The 90+ Study hosts a luncheon to appreciate and honor those individuals that have given their time and efforts to the research study. With more and more people volunteering for the research, the attendance continues to grow.


    The staff of The 90+ Study is truly grateful for all you have done to further our understanding of ways to aid future generations in leading long, productive and healthy lives. This is YOUR LEGACY.

    Through all of your passion and dedication to our mission, The 90+ Study at the University of California, Irvine has achieved a number of great successes. Our investigators, Drs. Claudia Kawas, Maria Corrada, and Annlia Paganini-Hill, are extremely well published in the field of aging and dementia and continue to be very successful in break-through research around the world.

    Ways to donate

    Click an option below:

    1. Click the button above, print the PDF and complete the form
    2. Checks are payable to “UCI FOUNDATION” with “THE 90+ STUDY” written in the memo area
    3.  Mail the filled in form and your check to:

             Claudia Kawas M.D., 1121 Gillespie, Irvine, CA 92697-4540

    1. Click the “Online Donations” button above and complete the online form.
    2. Be sure that The 90+ Study is the selected designation


    Interested in volunteering or know someone over 90 years old who might want to participant in
    The 90+Study?

    Take a look at the eligibility criteria listed below


    Click on the photo for a larger view.


    Contact us today to get started!

    Phone: (949) 768-3635


    Mailing address:

    24361 El Toro Road Suite 150

    Laguna Woods, CA 92867


    (949) 768-3635

    Mailing address:

    24361 El Toro Road Suite 150

    Laguna Woods, CA 92867