Final Research Plan

Cognitive Impairment in Older Adults: Screening

October 19, 2017

Recommendations made by the USPSTF are independent of the U.S. government. They should not be construed as an official position of the Agency for Healthcare Research and Quality or the U.S. Department of Health and Human Services.

The final Research Plan is used to guide a systematic review of the evidence by researchers at an Evidence-based Practice Center. The resulting Evidence Review will form the basis of the USPSTF Recommendation Statement on this topic.

The draft Research Plan was available for comment from June 29 to July 26, 2017.

Figure 1 is the analytic framework that depicts the five Key Questions to be addressed in the systematic review. The figure illustrates how screening for cognitive impairment in adults age 65 years or older may result in improved intermediate outcomes (decisionmaking) and health outcomes (patient, family/caregiver, and societal outcomes) (Key Question 1). There is also a question related to the accuracy of screening instruments used to detect cognitive impairment (Key Question 2) and potential harms of screening (Key Question 3). Additionally, the figure illustrates how interventions for early-stage dementia may have an effect on intermediate outcomes (decisionmaking) and health outcomes (patient, family/caregiver, and societal outcomes) (Key Question 4), and whether these interventions result in any harms (Key Question 5).

Abbreviation: MCI=mild cognitive impairment.

  1. Does screening for cognitive impairment in community-dwelling older adults in primary care–relevant settings improve decisionmaking, patient, family/caregiver, or societal outcomes?
  2. What is the accuracy of screening instruments to detect cognitive impairment in community-dwelling older adults?
  3. What are the harms of screening for cognitive impairment in community-dwelling older adults?
  4. Do interventions for mild to moderate dementia or mild cognitive impairment in community-dwelling older adults improve decisionmaking, patient, family/caregiver, or societal outcomes?
  5. What are the harms of interventions for mild to moderate dementia or mild cognitive impairment in community-dwelling older adults?

Contextual questions will not be systematically reviewed and are not shown in the Analytic Framework.

  1. Does diagnosis of cognitive impairment (either dementia or mild cognitive impairment) improve patient, family/caregiver, or clinician decisionmaking?
  2. What is the effectiveness of interventions to prevent mild cognitive impairment or dementia in adults without current cognitive impairment?

The Research Approach identifies the study characteristics and criteria that the Evidence-based Practice Center will use to search for publications and to determine whether identified studies should be included or excluded from the Evidence Review. Criteria are overarching as well as specific to each of the key questions (KQs).

  Included Excluded
Condition KQs 1–3: Any cognitive impairment (mild cognitive impairment* or dementia)

KQs 4, 5: Mild cognitive impairment* or mild to moderate dementia
KQs 4, 5: Severe dementia
Populations KQs 1–3: Community-dwelling older adults (including those residing in independent living facilities) age ≥65 years (or studies with a mean age ≥65 years) without a current diagnosis of mild cognitive impairment or dementia; informal caregivers taking some responsibility for the care of the patient, such as a spouse, partner, relative, or friend

KQs 4–5: Community-dwelling older adults (including those residing in independent living facilities) age ≥65 years (or studies with a mean age ≥65 years) with a current diagnosis of mild cognitive impairment or dementia; informal caregivers taking some responsibility for the care of the patient, such as a spouse, partner, relative, or friend
  • Studies comprised exclusively of persons diagnosed with depression or psychosis, alcohol use disorder, HIV/AIDS, Down syndrome, posttraumatic brain injury, metabolic disorders, Parkinson’s disease, Huntington’s disease, or stroke
  • Persons living in special settings outside of the community (e.g., hospitals, nursing or care homes, rehabilitation centers, other long-term care facilities)
  • Professional caregivers who are formally or professionally trained and paid a salary
Settings Primary care outpatient settings (ambulatory care), home, residential care facilities, assisted living facilities, and adult foster care All KQs: Hospitals, intermediate care facilities (e.g., nursing homes, rehabilitation facilities, subacute care facilities), emergency departments, or other settings not generalizable to primary care

KQs 1–3: Studies in which participants are recruited from memory, dementia, geropsychiatry, or neurology clinics
Screening Screening instruments that can be delivered in primary care in ≤10 minutes by the clinician or ≤20 minutes by the patient; informant instruments Screening instruments that take >10 minutes for clinician administration or >20 minutes for self-administration; biomarkers (cerebrospinal fluid, blood plasma, urine) or imaging (computed tomography, magnetic resonance imaging, positron emission tomography)
Interventions
  • Use of medications approved by the U.S. Food and Drug Administration (alone or in combination) for the treatment of dementia:
    • Acetylcholinesterase inhibitors (donepezil, galantamine, rivastigmine)
    • NMDA (N-methyl-D-aspartate) receptor antagonists (memantine)
  • Use of other medications or dietary supplements:
    • Medications aimed at cardiovascular risk reduction for treatment of vascular dementia (antiplatelet medications, antihypertension medications, HMG-CoA reductase inhibitors)
    • Nonsteroidal anti-inflammatory drugs (ibuprofen, naproxen, indomethacin, celecoxib)
    • Gonadal steroids (estrogen, progesterone, testosterone)
    • Vitamins, minerals, and antioxidants (B vitamins and folate, vitamins C and E, beta-carotene, omega-3 fatty acids)
  • Cessation of medications that may be contributing to cognitive impairment (e.g., anticholinergic medications, benzodiazepines)
  • Nonpharmacologic interventions aimed primarily at the patient, including cognitive training, rehabilitation, or stimulation, with or without motor skills training interventions; exercise interventions; nutrition counseling; multidisciplinary care interventions involving assessment and care coordination; and education-only interventions
  • Nonpharmacologic interventions aimed primarily at the caregiver or caregiver-patient dyad
  • Treatments for symptom management (e.g., agitation, psychosis, depression) of dementia (i.e., antipsychotics, antiepileptics, antidepressants, selective serotonin reuptake inhibitors)
  • Medications not approved by the U.S. Food and Drug Administration for the treatment of dementia or not available in the United States (e.g., tacrine)
  • Herbal supplements (e.g., ginkgo biloba)
  • Medical foods or fluids or nutrition therapy (e.g., meal replacement therapy)
  • Experimental or emerging therapies (e.g., amyloid disease-modifying treatments)
  • Interventions aimed at noncognitive symptom management (e.g., music, light, pet, reminiscence, or psychodynamic interpersonal therapy; nighttime home monitoring systems; Snoezelen® multisensory environments)
  • Respite care or day care interventions
Comparisons KQs 1, 3: No screening, usual care

KQ 2: Reference standard (clinical assessment or neuropsychologic testing with explicit diagnostic criteria, with or without expert consensus/conference)

KQs 3–5:
  • No intervention
  • Usual care
  • Wait list
  • Attention control
  • Minimal intervention
KQs 4, 5: Active intervention
Outcomes KQs 1, 4: Decisionmaking outcomes:
  • For patients and family/caregivers: Health care, legal, and financial planning (e.g., advanced directives); safety planning; living arrangements
  • For clinicians: Health care planning, including advanced directives; patient and caregiver education; safety planning; monitored medication use; screening and diagnostic decisions (e.g., cancer screening); and other treatment or management decisions
Patient-related outcomes:
  • Health-related quality of life
  • Incident dementia
  • Overall dementia severity
  • Cognitive function
  • Physical function (e.g., activities of daily living, instrumental activities of daily living)
  • Global function
  • Dementia-related symptoms/behaviors (e.g., neuropsychiatric disturbances, insomnia, depression, agitation, verbal aggression, apathy)
  • Safety (falls, other accidents)
  • Unanticipated health care utilization (emergency use/hospitalizations)
  • Institutionalizations/nursing home admissions
  • Medication adherence/compliance/errors

Family/caregiver-related outcomes: (a priori defined as primary or secondary outcomes in the trial)

  • Health-related quality of life
  • Global stress/distress
  • Caregiver burden
  • Depression
  • Anxiety

Societal outcomes: Safety (e.g., automobile accidents)

KQ 2: Sensitivity, specificity, likelihood ratios, positive and negative predictive values, area under the curve

KQ 3: Paradoxical effects (unwanted or unexpected direction of effects of outcomes), psychological harms (depression, anxiety), and harms due to labeling (psychological harms, insurance status, loss of driving privileges)

KQ 5: Serious adverse events (e.g., death, serious adverse drug reactions), adverse reactions from medications, unexpected medical attention (e.g., emergency department visits, hospitalizations), paradoxical effects (unwanted or unexpected direction of effects of outcomes), and psychological harms (depression, anxiety)
KQs 1, 4:

Decisionmaking outcomes: Cost-related outcomes

Patient-related outcomes: Cost-related outcomes; patient satisfaction (other than health-related quality of life); biomarker protein levels, brain matter volume, and brain cell activity level; function markers (e.g., Timed Up and Go Test, 6-meter timed walk, Functional Reach Test)

Family/caregiver-related outcomes: Cost-related outcomes; family/caregiver satisfaction (other than caregiver burden and health-related quality of life)

Societal outcomes: Cost-related outcomes

KQ 2: Cost-related outcomes

KQs 3, 5: Patient or family/caregiver dissatisfaction (other than psychological harms or patient adherence)
Timing of outcome assessment KQs 1, 4: ≥3 months after baseline

KQs 3, 5: No minimum followup
KQs 1, 4: <3 months after baseline
Countries Studies conducted in countries categorized as “Very High” on the 2014 Human Development Index (as defined by the United Nations Development Programme) Studies conducted in countries not categorized as “Very High” on the 2014 Human Development Index
Study designs KQs 1, 4: Randomized, controlled trials; nonrandomized, controlled trials

KQ 2: Diagnostic accuracy studies

KQs 3, 5: Randomized, controlled trials; nonrandomized, controlled trials; open-label extensions of KQ 4 trials; cohort or case-control studies
KQs 1, 4: Observational studies

KQ 2: Case-control studies

KQ 3, 5: Case series, case reports

KQ 5: Cohort or case-control studies with <1,000 participants
Publication language English Languages other than English
Study quality Fair- or good-quality studies Poor-quality studies (according to design-specific USPSTF criteria)

* Mild cognitive impairment is distinguished from dementia by virtue of causing cognitive impairment that is not severe enough to interfere with independence in daily function, although the nomenclature, definitions, and criteria may vary within the included body of evidence.

Includes major dementia syndromes due to Alzheimer’s disease, vascular dementia, frontotemporal dementia, dementia with Lewy bodies, and dementia of mixed etiology.

A draft Research Plan was posted on the USPSTF Web site for public comment from June 29 to July 26, 2017. In response to public comment, the USPSTF defined mild cognitive impairment and clarified the specific etiologies of dementia that will be included, and clarified that studies conducted exclusively among persons with potential reversible causes of dementia will be excluded. The USPSTF made no substantive changes that altered the scope of the review.