Dementia in the Oldest Old (Dementia 2013)

Educational Objectives

The goal of this program is to improve the diagnosis and management of dementia in the elderly. After hearing and assimilating this program, the clinician will be better able to:

1. Diagnose and manage dementia in patients >90 years old.

Summary

María M. Corrada, ScM, ScD
Associate Adjunct Professor of Neurology, University of California, Irvine, Irvine, CA

Population: Oldest old originally defined as age >85 years, now defined as age >90 years; fastest growing segment of population in United States.

Epidemiology of dementia: Prevalence — dementia occurs in ≈45% of women and ≈28% of men ≥90 years old; incidence — no difference in rates between men and women; rate increases with age (13% per year in ages 90 to 94; 21% per year in ages 95 to 99; 41% per year in centenarians); longer life span may explain higher prevalence among women.

Risk factors: Age — strongest risk factor for dementia; apolipoprotein E (APOE) ´4 allele — although associated with risk in younger elderly, allele not associated with increased risk in oldest old; hypertension — midlife hypertension increases risk for dementia and Alzheimer disease (AD) in younger elderly but appears protective in oldest old; proposed explanations include (1) prevention of hypoperfusion caused by stiffening of arteries, (2) beneficial effects of certain antihypertensive medications on risk for dementia and AD, (3) uncontrolled hypertension may be marker for differential health care, and (4) neurodegenerative pathology leads to hypoperfusion (ie, hypertension may signal absence of neurodegenerative process).

Diagnosis: Standard criteria used for diagnosis; challenge lies in differentiating cognitive impairment from effects of normal aging; based on comparison with normative data from neuropsychological testing, cognitive impairment defined as performance below 10th percentile or 1.5 standard deviations below mean for age group; special needs — potential effects of sensory loss should be mitigated by eg, larger font size, amplified audio, and offering testing in print and audio formats; frequent breaks may counteract fatigue.

Pathology: AD pathology — amyloid plaques and neurofibrillary tangles most commonly associated with dementia in oldest old but also occur in those without dementia; vascular pathology — seen in 75% to 90% of individuals at autopsy; in oldest old, large-vessel infarcts less common but lacunar and microinfarcts more common compared to rates seen in younger populations; other neuropathologies — hippocampal sclerosis seems to increase with age but rarely seen in elderly patients without dementia; diffuse Lewy body disease and frontotemporal dementia relatively rare in oldest old patients; mixed subclinical pathologies — ≈25% of oldest old with dementia do not have obvious underlying pathology; additive or synergistic effects of multiple (low-level) pathologies may result in dementia.

Management: Similar approach as in younger elderly, but age-related changes in pharmacokinetics and pharmacodynamics often result in lower dosage requirements; careful monitoring and frequent reassessment help prevent adverse events; nonpharmacologic interventions (eg, behavioral therapies, music, exercise) especially important in oldest old; development and adherence to strict daily routine can help these patients remain oriented and reduce risk for agitation and behavioral disturbances (see Continuum article for more detailed discussion).

Readings

Bullain SS, Corrada MM. Dementia in the oldest old. Continuum (Minneap Minn) 2013;19(2); Bullain SS, Corrada MM, Shah B, et al. Poor physical performance and dementia in the oldest old: the 90+ study. JAMA Neurol. 2013;70(1):107-13.

Disclosures

For this program, the following was disclosed: Dr. Bullain has received a travel scholarship from the Orange County Chapter of the Alzheimer’s Association to attend an international conference and receives grant support and other salary support from the National Institute on Aging; Dr. Corrada receives research support from the Alzheimer’s Association and the National Institute on Aging. Unlabeled Use of Products/Investigational Use Disclosure: Drs. Bullain and Corrada report nothing to disclose. To view disclosures of planning committee members with relevant financial relationships, visit: audiodigest.org/continuumaudio/committee. All other members of the planning committee report nothing to disclose.

Acknowledgements

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0 CE contact hours.

Lecture ID:

CA020801

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.