Early Theories of AgingEarly Theories of Aging
Thanatophobia
Extend maximum life spanHippocrates – gradual loss of body heatErasmus Darwin – reduced responses to stimuli,
loss of excitabilityOthers – metabolic rate, irradiation, genetics“geriatrics” coined in 1914First geriatric medical journal published in 1945ACSM founded in 1954NIA created in 1974
Theories of AgingTheories of AgingPsychological
◦ Maslow’s Hierarchy of Needs (1943)◦ Erikson’s Psychological Stages (1956)◦ Selective Optimization with Compensation (SOC,
1980)Sociological
◦ Activity◦ Continuity
Biological◦ Damage◦ Genetic◦ Gradual Imbalance
Theories of AgingTheories of AgingPsychological
◦Primarily related to success◦Personal development
Sociological◦Engagement◦Experience & environment
Maslow’s Hierarchy of Needs: Theory of Successful Aging
Theories of AgingTheories of AgingErikson’s Psychosocial Stages
◦Development through late adulthood◦Positive/Negative Outcomes
Late Adulthood◦Pride & satisfaction vs. lack of
accomplishment◦Dignity & acceptance vs. frustration
Keys: close relationships; productivity with family and/or work; evaluation of the rear view
Theories of AgingTheories of AgingSelective Optimization with
Compensation (Baltes & Baltes, 1990)◦Select priorities/likes/most important◦Optimize skills and talents◦Compensate for decrements in ability
Examples◦Playing music◦Lifting weights◦Running
Theories of AgingTheories of AgingSOC
◦ Functional competence is keyRelated concepts
◦ Self-efficacy (Bandura, 1977)◦ Self-esteem◦ Control ◦ Cognitive capacity
Theories of Aging: Theories of Aging: SociologicalSociologicalActivity Theory (Havighurst, 1961)
◦Engaged in mental and physical activities
◦Community/family/professionContinuity (Atchley, 1971)
◦Carry forward positive habits, relationships, regardless of advancing age
Can social beings successfully age without solid social connections?
Cognitive function?
Theories of AgingTheories of Aging
Theories of AgingTheories of AgingDamage from wear and tear
◦Chemical reactions that occur naturally in the body begin to produce a # of irreversible defects in molecules.
◦What is the source of “microinsults”? Physical Chemical Infectious Mechanical
Injury
Loss of function &System failure
Repair
Theories of AgingTheories of Aging
Theories of AgingTheories of AgingFree-radical theory (damage)
◦Chemical compounds that contain an unpaired electron in an outer orbital
◦Able to link to tissue and cause damage
Theories of AgingTheories of Aging
Mitochondrial respiration– “leaking intermediates”
Superoxide dismutase
Theories of AgingTheories of AgingFree radical targets
◦Cell membranes◦DNA & RNA◦Enzymes
Damage to tissues, ultimately systems
Theories of AgingTheories of AgingAccumulation of defects in
metabolic pathwaysDoes aging originate in the
mitochondria?Oxidation of mitochondrial DNAWidespread impact
Theories of AgingTheories of AgingStrategy for reducing free
radicals:◦Consumption of Vitamins E and C
“anti-oxidants”
◦Mechanism?◦Use of supplements?
Theories of AgingTheories of Aging
Cross-linkage (damage)◦Corrupted DNA not repaired◦Cross-linking occurs in protein-based
collagen fibers◦Over time, results in
Stiffening of tissue Rigidity of blood vessels Tight ligaments & tendons Cataracts Atherosclerosis
Theories of AgingTheories of Aging
Genetic theories◦Genes related to
pathologies ◦Could dictate cellular
aging◦DNA mutations of
mitochondria build during lifetime
Theories of AgingTheories of Aging
Hayflick Limit Cells will divide & reproduce only a limited
number of times “Cell Clock” Number is genetically programmed
Limitations
Theories of AgingTheories of Aging
Telomere Hypothesis◦Shortens with each
replication of the chromosome
◦Replication at a fixed rate may indicate that the telomere is the “clock” that determines the lifespan of any given cell
◦Dolly’s fate
Theories of AgingTheories of AgingGradual Imbalance Theory
◦Nervous system◦Endocrine system◦Impaired relationship btwn the two
Hormones impactedAdaptation impairedIs aging the result of decreased
ability to survive stress??
Theories of AgingTheories of AgingThere is no overwhelming support for just one biological theory of aging.
Likely theories overlap and each explain some aspect(s) of aging
Slowing the Aging ProcessSlowing the Aging Process
Improve nutrition total food consumedMaintain general activity levels
Have social/community involvement
Perform moderate amounts of physical exercise
Slowing the Aging ProcessSlowing the Aging ProcessCaloric restriction
◦Total amt of food is reduced How much?
◦Major nutrients, minerals, & vitamins necessary for health are maintained
Slowing the Aging ProcessSlowing the Aging ProcessBiosphere 2 experimentsN = 8; ~2 yearsLower
◦ Metabolic rate◦ Body temperature◦ SBP & DBP◦ Blood glucose◦ Insulin◦ Thyroid hormones
Okinawan populationExperimental data in
humans?
Slowing the Aging ProcessSlowing the Aging ProcessGeneral activity level
◦Active in life◦Social contacts◦Taking care of self◦Living the “good life”
Role of PA/Exercise/Sport?Role of PA/Exercise/Sport?Compression of morbidity?Decrease premature mortality?SOC?Social opportunities?
Quality of LifeQuality of Life
The difference between active living & just being alive.
Active life expectancy
Quality of Life (more to Quality of Life (more to come)come)Activities of
Daily Living (ADLs)◦Walking◦Dressing◦Bathing/
toileting◦Eating◦Getting up from
a bed or chair
Instrumental Activities of Daily Living (IADLs)◦Managing
finances◦Using the
telephone◦Light housework◦Heavy housework◦Meal preparation◦Shopping
Spiritual health: Relationships, values, purpose
SummarySummaryFactors that optimize
successful aging:◦Avoiding disease◦Engaging in life activities◦Maintaining high cognitive
and physical function