Epi of Aging Flashcards
Change in shape of age pyramid due to increasing proportion of older adults in population
Rectangularization
Falling fertility rates & rising life expectancy
Reasons for Increased Number of Older Adults
Time required/expected for percentage of population aged ≥ 65 to rise from 7% to 14%; greatest in developing countries
Hyperaging
Decrease in infectious disease (communicable, maternal, perinatal, & nutrition conditions) vs. increase in non-communicable disease (chronic conditions)
Epidemiologic Transition
Physical, cognitive, & social
Domains of Aging
Numerical age since birth
Chronological Age
Rate of aging; dependent on other factors (e.g. gender, education, BMI, sleep, etc.)
Biological Age
Major contributor to lower quality of life (loss of autonomy, decreased social interaction, emotional burden); risk factor for disease; increased healthcare utilization & costs; predictor of mortality
Disability
Mobility, complex function (IADLs), basic self-care (ADLs), upper-extremity function
Domains of Physical Function
Walking 1/4-1/2 mile, climbing stairs, heavy housework
Mobility
Higher functioning tasks required for independent living; shopping, using telephone, balancing checkbook/managing money, preparing meals, housekeeping, managing/taking medications
Instrumental Activities of Daily Living
Basic self-care tasks required for independent living; bathing/showering, transferring in/out of bed/chair, dressing, toileting, eating
Activities of Daily Living
Grasping or handling, lifting, carrying objects
Upper-Extremity Function
Self-report; more common & easy to collect (gold standard); questions about ability, difficulty, & dependency
Subjective Assessments of Function
Performance-based measures; more sensitive in showing change over time; SPPB, gait speed, 400-meter walk, chair stands, muscle strength (e.g. grip strength), dexterity & fine motor skills, static balance
Objective Assessments of Function
Time to walk 4-meters at usual pace, time to complete 5 chair stands, & standing balance tests; 10-12 = high, 4-9 = intermediate, 0-3 = low; predictive of disability
Short Physical Performance Battery
Declines with age; < 1.0 m/s predictive of negative health outcomes
Gait Speed
Disability framework; pathology –> physiological impairment –> limitations in function & performance –> disability
Nagi Scheme
Disability Framework; pathology –> functional impairment –> functional limitation –> disability; risk factors for impairment & intra-/extra-individual factors for limitation
Verbrugge & Jette
Age-related state of vulnerability; progressive syndrome with clinical & sub-clinical stages; high risk for mortality, falls, disability, & hospitalization; characteristics include weakness/sarcopenia, deconditioning/fatigue, poor appetite, weight loss, balance/gait abnormalities, risk of falls, delirium, incontinence, disability, dependency
Frailty
Frailty model; weight loss, weakness, exhaustion, slowed walking speed, low activity (at least 3)
Fried Frailty Phenotype
Frailty model; global measure of fitness & frailty in older adults (many criteria)
Rockwood Model
Frailty model; score of 1-7 based on descriptions (very fit to severely frail)
Canadian Study of Health & Aging Clinical Frailty Score
Collection of mental processes controlled by brain; attention, memory, language, learning, reasoning, problem solving, decision making
Cognitive Functioning
Memory, attention, perceptual/visuospatial ability, language, executive function
Cognitive Domains
Recall words after hearing them read aloud; tests memory, language (sum of words recalled), attention (trial 1 recall), & executive function (order of recalled items, types of errors); Hopkins Verbal Learning, Auditory Verbal Learning, California Verbal Learning, Bushke Selective Reminding
Word-List Learning Tests
Trail making, digit symbol
Timed Tests
Name as many items (e.g. animals) as possible over certain time (e.g. 60 seconds)
Count Tests
Most common measure of global mental status; orientation, registration, attention, calculation, recall (memory), language; valid as screening test for all-cause dementia in clinical but not community samples; poor measure of longitudinal change
Mini-Mental State Exam
Planning, problem solving, strategizing (candle problem, semantic fluency); shifting (trail making, Wisconsin card sort); inhibiting (Stroop, Wisconsin card sort); goal-directed behavior (tests that simulate real-world experience)
Executive Function Tests
Brief test of attention, digit span
Attention Tests
Boston naming test, phonemic fluency
Language Tests
Visual search, pattern comparison
Visuospatial Tests
Pre-clinical –> mild cognitive impairment –> dementia; distinct trajectory from normal cognitive decline
Continuum of Alzheimer’s Disease
Increase in Alzheimer’s biomarkers during pre-clinical & MCI stages before clinical disease; beta-amyloid –> tau –> brain structure –> memory –> clinical function
Jack’s Dynamic Biomarkers Hypothesis
Intermediate state between normal & impaired cognition; problems/complaints about memory or other domain but everyday functioning not yet impaired
Mild Cognitive Impairment
Progressively debilitating, chronic disorder characterized by loss of independent functioning; pathology understood but not etiology; poor episodic memory but procedural memory relatively well-preserved
Alzheimer’s Disease
Acute change in cognitive function (particularly attention & memory); marker of absence of cognitive reserve; most common among patients with AD or in ICU; associated with significant decline in cognitive function
Delirium
Selection bias (recruitment, attention, survival), measurement error/instrument reliability, unequal interval scaling properties (floor/ceiling effects), time scale, high-dimensional exposure data, practice effects
Methodological Challenges of Studying Cognitive Aging
Participants improve with repeat testing due to familiarity, procedural memory, or episodic memory; difficult to know true pace of cognitive decline without adjusting; different ways to model based on varying assumptions
Practice Effects
Change which characterizes populations born at particular point in time; independent of aging process (e.g. Flynn Effect)
Cohort Effect
On average everyone in successive generations tends to perform better on tests than their parents’ generation
Flynn Effect
Change which occurs at particular time & affects all age groups/cohorts uniformly
Period Effect
Measure of global mental status; orientation to time/place, registration, mental speed/flexibility, memory
Montreal Cognitive Assessment
Gender with significantly higher incidence of hip fracture; gender with significantly higher 1-year mortality after hip fracture
Women vs. Men
Bone turnover, bone mass, bone quality, risk of fall, force of impact
Methods to Assess Risk of Hip Fracture
18-33% die within 1-year; average 3-8 days in hospital, 15-25% institutionalized for at least 1-year; 25-75% do not regain function; loss of bone & muscle mass; increase in functional limitations & disability; inflammatory response; increase body fat
Consequences of Hip Fracture
Osteoporosis, sarcopenia, chronic conditions, etc.
Pathology Leading to Hip Fracture
Medical conditions existing simultaneously, either independently or with related medical condition; conditions can exacerbate each other & confound effects; associated with current & future risk of disability & mortality
Comorbidity
Diabetes & heart disease
Lower Extremity Limitations
Diabetes & osteoarthritis
Mobility Limitations
Prevent disease onset
Primary Prevention
Identify disease in sub-clinical phase (e.g. screening) & prevent progression
Secondary Prevention
Minimize symptoms of disease & maximize quality of life
Tertiary Prevention
Vascular conditions, hearing impairment, diabetes, & arthritis
Most Common Chronic Conditions
Recruitment & retention (burden), loss to follow-up, missing data, competing risks, reverse causation, heterogeneity
Challenges of Studies of Older Adults
Risk factor influencing health vs. health influencing risk factor
Reverse Causation
Predicts 10-year mortality for patient with range of chronic conditions; weighted score summed to predict mortality
Charlson Index
Complex treating concurrent diseases (interactions, contraindications, prioritizing treatment, polypharmacy, continuum of care)
Healthcare Implications of Comorbidity
Need for rehabilitation/community services to decrease risk of social isolation, dependency, & mortality
Healthcare Implications of Disability
Vulnerability to stressors; treat underlying conditions & prevent adverse events
Healthcare Implications of Frailty
Extrinsic factors play negative role vs. neutral or positive role in aging
Usual vs. Successful Aging (Rowe & Kahn)
Slower rate of metabolism associated with greater longevity; resting metabolic rate decreases with age but may be truncated by comorbidities (diseases require extra energy to maintain body function)
Rate of Living Theory
Mood disorder; symptoms include sadness, irritability, overreacting, change in appetite, listlessness, restlessness, sleep changes, forgetfulness, brain fog, feeling worthless, feeling guilty, thoughts of death or suicide
Depression
Depressed mood or loss of interest/pleasure for more than 2 weeks + impaired function + 5 symptoms
Major Depressive Disorder
Depressed mood or loss of interest/pleasure for over 2 weeks + 2-4 symptoms; not linked to substance abuse or grief
Minor Depression
Depressed mood for over 2 years + 2-5 symptoms; not linked to chronic condition
Dysthimia
Triggers include social isolation, life losses, physical illness, & medications; signs include physical complaints, mood changes that don’t let up, problems concentrating, apathy, deficits in executive function & processing speed; vascular risk factors
Depression in Older Adults
Proportion of true positives correctly identified by test; A/(A+C)
Sensitivity
Proportion of true negatives correctly identified by test; D/(B+D)
Specificity
Proportion of those with disease among those that test positive; A/(A+B); depends on disease prevalence
Positive Predictive Value
Proportion of those without disease among those that test negative; D/(C+D); depends on disease prevalence
Negative Predictive Value
PHQ-9 (cut-off 10), CES-D (cutoff 21), GDS (cutoff 10)
Questionnaires for Depression
2 leading cause of disability-adjusted life years, cause of 2/3 suicides, risk factor for mortality, risk factor for MCI & dementia
Consequences of Depression
CVD depression (unknown directionality); cardinal features include vascular disease/risk factors, secondary features include cognitive impairment, guilt, poor insight, & disability, cardiovascular risk factors
Vascular Depression
Percent of cases in population that would be avoided if exposure eliminated; depends on prevalence of exposure in population
Population Attributable Fraction
Under-recognition, lack of trained staff members, stigma, overlap with symptoms of physical illness/medications
Barriers & Diagnostic Challenges for Depression
Rapid development in early life –> short maintenance period –> gradual decline in function
Trajectory of Aging
Changes in body composition, energy imbalance production/utilization, homeostatic dysregulation, & neurodegeneration
Aging Phenotypes & Geriatric Syndromes
Reduced lean body mass, increased fat mass, reduced bone density, reduced muscle mass/quality
Body Composition Changes
Loss of muscle mass late in life; associated with decreased mobility, function, & energy regulation
Sarcopenia
High basal metabolic rate & lower fitness (VO2 max)
Energy Imbalance
Energy use at rest
Basal Metabolic Rate
Energy use at maximum capacity
VO2 Peak
Insulin resistance, low testosterone, anemia, low-grade chronic inflammation, immunosenescence
Homeostatic Dysregulation
Brain atrophy, decreased cognitive function, amyloid plaques, impaired balance
Neurodegeneration
Traditional method of measurement; surveys to assess frequency, intensity, & duration of activity & function; subject to error, failure to capture variability of activity, difficult to discern benefits of lifestyle activities, burden, difficult interpretation of responses
Self-Reported Physical Activity
Oxygen consumption of 70 kg, 40-year-old at rest; higher values associated with more vigorous activities; may not translate to older adults
Metabolic Equivalents (METs)
Use of technologies to detect accelerations in 1-3 orthagonal planes; shows diurnal daily pattern of activity; limited ability to assess non-impact activities, provides little information on activity type/purpose/context, cannot assess relative intensity without calibration, can be difficult to interpret
Objectively Reported Physical Activity
Average number of years individual of given age is expected to live if current mortality rates continue to apply
Life Expectancy
Longest documented survival of member of species; 122 years for humans
Life Span
Summarizing technique used to describe pattern of mortality & survival in populations
Life Table
Average number of years of remaining life which is disability free for individual of given age
Active Life Expectancy
Average number of years of remaining life with disability for individual of given age; total life expectancy - active life expectancy
Disabled Life Expectancy
When maximum life expectancy reached, postponement of onset of disease & disability over time; when maximum life expectancy not reached, this, dynamic equilibrium, or expansion of morbidity may occur
Compression of Morbidity
Prevalent rate model (exit = death only), double-decrement model (exit for death or disability, but recovery from disability possible), or multistate/increment-decrement model (multiple exits & re-entries)
Life-Table Models to Account for Active Life Expectancy
Higher education, lower prevalence of chronic conditions, improvements in nutrition & public hygiene, better health promotion/medical therapy
Factors Influencing Decline in Disability Rates
Coronary heart disease & cancer
Chronic Conditions Causing Death without Disability
Arthritis
Chronic Condition Causing Most Disability
Information processing speed & motor skills
Link Between Cognition & Mobility
Learned movement that is smooth & efficient due to neural mapping; activate neurons to activate muscles to make smooth, coordinated movements; irregular velocity, stiff movement, & unpredictable sub-movements during learning
Motor Skill
Generalized slowing (motor & psychomotor functions), inefficiency (increased energetic cost & variability), reduced reserve, & reduced plasticity
Signs of Loss of Motor Skill
Secondary prevention; presumptive identification of unrecognized disease or defect by application of tests; not intended to be diagnostic but to detect & treat sub-clinical disease
Screening
Independent panel of non-federal experts in prevention & evidence-based medicine composed of primary care providers; conducts scientific evidence reviews of clinical preventive health care services & develops recommendations
United States Preventive Services Task Force (USPSTF)
Adapting USPSTF to Older Adults
Consider heterogeneity in life expectancy, health status, & goals
Act of providing unpaid assistance & support to family members/acquaintances who have physical, psychological, or developmental needs
Caregiving
Family member, friend, or neighbor of person with disability who provides regular, ongoing assistance to person because of disability; unpaid caregiving; can be primary vs. secondary, spouse vs. non-spouse, living vs. not living with recipient
Informal Caregiver
Difficult to construct comparable samples & convenience samples biased from population-based findings
Methodological Challenges of Studying Caregiver Health
Caregiving often chronic stressor (primary stressor –> care provision vs. secondary stressor –> life changes); stress depends on how challenge is perceived, external resources, & cultural expectations
Stress Process Model
20% informal caregivers report high strain –> greater risk for depression & worse physical health
Effects of Caregiving
Caregivers experience longevity benefit as compared to non-caregivers; healthier individuals may be more likely to take on caregiving roles
Healthy Caregiver Hypothesis
Decreasing birth rates, decreasing marriage rates, projected increase in proportion of older adults, middle-aged population projected to remain constant
Factors Contributing to Caregiver Shortage
Puts individuals & populations in context; tasks & challenges vary depending on transition point & within relevant social fields/contexts; tasks & challenges determined by normative age-graded influences (ontogenic), normative history-graded influences (cohort effects), & non-normative life events
Life Course Approach
Accelerometers for physical activity, biomarkers for AD progression, big data, data sharing panels, etc.
Examples of Objective Measurement
Meyer –> observe patients; psychoanalytic –> interact with patients; empirical –> identify patients, count them, & sensitivity/specificity
Psychiatric Epidemiology Epochs
