Longevity

Life Expectancy and Life-Span

• life span: maximum number of years an individual can live

• improvements in medicine, nutrition, exercise, and lifestyle have increased our life expectancy

• life expectancy: number of years that the average person born in a particular year will probably live

• Life Expectancy

  • the US is considerably better than some and somewhat worse than others in life expectancy compared to other countries

  • differences in life expectancies across countries reflect factors such as health conditions and medical care throughout the lifespan

  • US has one of the lowest growth rates in life expectancy

    • highest child and maternal mortality rates, homicide rate, and bmi index of high-income countries

  • african americans have the lowest life expectancy, then non-latino whites, then latinos

    • latino health paradox: latinos live 3.3 years longer than non-latino whites despite having lower educational attainment and income levels

      • migration patterns, extended family connections, and rates of smoking

  • women have a higher life expectancy than men

    • health attitudes, habits, lifestyles, and occupations

    • men are more likely than women to die from most of the leading causes of death in the US

      • cancer of the respiratory system, motor vehicle accidents, cirrhosis of the liver, emphysema, and heart disease

    • women are more likely than men to die from alzheimers and some aspects of cardiovascular disease

    • biological factors

      • women have more resistance to infections and degenerative diseases

  • longest average longevity in the US belongs to Seventh Day Adventists

• Centenarians: individuals 100 years and older

  • in developed countries, the number of centenarians is increasing at 7% a year

  • The US has the most centenarians, then China, Japan, and England

  • supercentenarian: applied to individuals who live to be 110

The Young-Old and the Oldest-Old

• young-old: 65-84 yrs

• oldest-old: 85+

  • mostly female - widowed and live alone, if not institutionalized

    • majority hospitalized and die alone in a hospital or institution

• functional age: person’s ability to function

• oldest-old face a number of problems

  • sizable losses in cognitive potential and ability to learn

  • increase in chronic stress

  • substantial prevalence of physical and mental disabilities

  • high levels of frailty

  • increased loneliness

  • difficulty of dying with dignity

• compared with the oldest-old, the youngest-old have a substantial potential for physical and cognitive fitness, higher levels of emotional well-being, and more effective strategies for mastering the gains and losses of old age

• three fourths of oldest-old are not institutionalized and continue to live in the community with good health and no activity limitations

Biological Theories of Aging

• Evolutionary Theory of Aging: benefits conferred by evolutionary selection decrease with age

  • natural selection has not eliminated many harmful conditions and nonadaptive characteristics in older adults bc natural selection is linked to reproductive fitness

  • this theory doesn’t account for cultural differences

• Genetic/Cellular Process Theories

  • Cellular Clock / Telomere Theory

    • cells can divide a maximum of 75-80 times

    • as we age our cells become less capable of dividing

    • upper limit of the human life-span potential is 120-125 yrs

    • each time a cell divides, the telomeres become shorter

      • after 70 or 80 replications, the telomeres are dramatically shortened and the cell can no longer reproduce

  • Free-Radical Theory

    • people age because when cells metabolize energy, the by-products include unstable oxygen molecules known as free radicals

    • free radicals ricochet around the cells, damaging DNA and other cellular structures

    • overeating is linked with an increase in free radicals

  • Mitochondrial Theory

    • aging is due to the decay of mitochondria

    • decay is caused by oxidative damage and loss of critical micronutrients supplied by the cell

    • defects in mitochondria are linked w cardiovascular disease, neurodegenerative diseases, parkinsons, diabetic kidney disease, and impaired liver functioning

    • mitochondria play important roles in neuronal plasticity

  • Sirtuin Theory

    • sirtuins: family of proteins that have been linked to longevity, regulation of mitochondria functioning in energy, possible benefits of calorie restriction, stress resistance, etc etc

  • mTOR Pathway Theory

    • mTOR pathway: cellular pathway that involves the regulation of growth and metabolism

    • pathway is linked to longevity and reducing cognitive decline

• Hormonal Stress Theory

  • aging in the body’s hormonal system can lower resistance to stress and increase the likelihood of disease

  • allostasis: when faced with external challenges such as stressful situations, the human body adapts by altering internal physiological processes

    • allostatic load: a wearing down of body systems due to constant activity

The Course of Physical Development in Late Adulthood

The Aging Brain

• The Shrinking, Slowing Brain

  • the brain loses 5 to 10 percent of its weight between the ages of 20 and 90

  • brain volume also decreases

  • decrease in brain volume is due mainly to

    • shrinkage of neurons

    • lower numbers of synapses

    • reduced length and complexity of axons

    • reduced tree-like branching in dendrites

  • declines in memory functioning were linked to lower gray matter volume

  • brain volume loss occurs in individuals with disorders such as alzheimers

  • some areas of the brain shrink more than others

    • prefrontal cortex shrinks the most with aging

      • decreased working memory

      • slower motor behavior

    • sensory regions are less vulnerable to the aging process

  • slowing of function in the brain and spinal cord begin in middle adulthood and accelerates in late adulthood

    • affects physical coordination and intellectual performance

  • reduced synaptic functioning and decreased production of some neurotransmitters

    • reductions in acetylcholine are linked to small declines in memory function and to the severe memory loss linked to alzheimers

    • normal age-related reductions in dopamine may cause problems in planning and carrying out motor activities

    • severe reductions in dopamine are linked to age-related diseases characterized by a loss of motor control, like parkinsons

• The Adapting Brain

  • even in late adulthood, the brain loses only a portion of its ability to function

  • activities older adults engage in can influence the brain’s development

    • higher levels of aerobic fitness were linked with greater volume in the hippocampus and better memory

  • adaptiveness of the human brain in older adults

    • possibility that the brain might be able to generate new neurons

      • neurogenesis: generation of new neurons

      • neurogenesis has only been documented in the hippocampus and the olfactory bulb

    • role of dendritic growth

      • dendritic growth might compensate for the possible loss of neurons through the seventies but not through the nineties

      • lack of dendritic growth in older adults could be due to a lack of environmental stimulation and activity

    • adaptive potential of delateralization

      • brain activity in the prefrontal cortex is lateralized less in older adults than in younger adults when they engage in cognitive tasks

      • using both hemispheres may improve the cognitive functioning of older adults

Sleep

• 5% or more of older adults complain of having difficulty sleeping

• engage in more light sleep and less deep sleep

  • more likely to occur in men

• older adults who slept 6 hours or less per day were more likely to have fair or poor health

• poor sleep is a risk factor for falls, obesity, lower cognitive function, and earlier death

• sleep duration of more than seven hours per night in older adults was linked to longer telomere length

• even just one night of partial sleep deprivation activated DNA damage characteristic of biological aging

• excessively long sleep duration is often an indicator of less effective physical and cognitive functioning

  • long sleep duration predicted an increase in all-cause mortality in individuals

  • more likely to have cardiovascular disease and diabetes

• older adults who engaged in a higher level of overall physical activity, leisure-time exercise, and household activity were less likely to have sleep problems

Physical Appearance and Movement

• in late adulthood, the changes in physical appearance that began occurring during middle age become more pronounced

• wrinkles and age spots

• we become shorter in late adulthood because of bone loss in our vertebrae

• weight usually drops after 60 yrs because of muscle loss

  • gives our bodies a sagging look

  • long-term aerobic exercise was linked with greater muscle strength

• older adults move more slowly than young adults

  • obesity contributes to mobility limitations in older adults

  • regular walking decreases the onset of physical disability and reduces functional limitations in older adults

• decreased walking speed in older adults is associated with limited mobility, less community participation, greater cognitive decline, and increased risk of falls

• risk of falling in older adults increases with age and is greater for women than for men

  • exercise reduces falls in adults 60+

  • walking was more effective than balance training for reducing falls in older adults

Sensory Development

• Vision

  • visual decline in late adulthood is linked to cognitive decline and having fewer social contacts and engaging in less challenging social/leisure activities

  • cognitive decline was steepest in individuals with both visual and hearing problems

  • declining visual acuity, color vision, and depth perception are associated with aging

  • Visual Acuity

    • in late adulthood, the decline in vision that began for most adults in early or middle adulthood becomes more pronounced

    • visual processing of information declines in older adults

    • night driving is difficult because of diminishing sensitivity to contrasts and reduced tolerance for glare

    • older individuals take longer to recover their vision when going from a well-lighted room to semidarkness

    • visual decline can be traced to a reduction in the quality or intensity of light reaching the retina

      • might be accompanied by degenerative changes in the retina, causing severe difficulty in seeing

    • sensory decline in older adults is linked to a decline in cognitive functioning

    • visual decline was related to slower speed of processing info, which was associated with greater cognitive decline

  • Color Vision

    • may decline in age as a result of the yellowing of the lens of the eye

    • most likely to occur in the green-blue-violet part of the color spectrum

  • Depth Perception

    • changes little after infancy until adults become older

    • depth perception typically declines in late adulthood

    • can make steps and street curbs difficult to manage

  • Diseases of the Eye

    • Cataracts: thickening of the lens of the eye that causes vision to become cloudy and distorted

      • partial loss of vision due to cataracts experienced by 30% of people by age 70

      • cataracts can be treated by glasses

      • if they worsen, the cloudy lens can be surgically removed and replaced

      • diabetes is a risk factor for the development of cataracts

    • Glaucoma: involves damage to the optic nerve because of the pressure created by a buildup of fluid in the eye

      • can be treated with eye drops

      • if left untreated, glaucoma can destroy a person's vision

    • Macular degeneration: deterioration of the macula of the retina

      • unable to see clearly what is right in front of them

      • cigarette smoking contributes

      • can be treated with laser surgery

      • difficult to treat

      • leading cause of blindness in older adults

• Hearing

  • age of older adults is important in determining the degree of decline

  • decline in vision and hearing is much greater in individuals 75+ than in individuals 65-74 yrs

  • hearing impairment usually doesn’t become much of an impediment until late adulthood

  • older adults often don’t recognize that they have a hearing problem, deny that they have one, or accept it as a part of being old

  • hearing loss in older adults is linked to declining performance in activities of daily living, cognitive functioning, and language

  • dual sensory loss in vision and hearing

    • linked to reduced social participation and less social support

    • linked to increased loneliness

    • greater functional limitations, cognitive decline, and communication problems

    • more depressive symptoms

• Smell and Taste

  • most older adults lose some of their sense of taste or smell or both

  • older adults show a greater decline in their sense of smell than in their sense of taste

  • smell and taste decline less in healthy older adults

  • poorer sense of smell in older adults was associated with depression and loneliness

• Touch and Pain

  • changes in touch and pain sensitivity are associated with aging

  • decline in touch sensitivity is not problematic

  • older adults who are blind retain a high level of touch sensitivity which is linked to their use of active touch in their daily lives

  • 60-75% of older adults report at least some persistent pain

    • back pain, peripheral neuropathic pain, and chronic joint pain

  • presence of pain increases with age in older adults, and women are more likely to report having pain

  • older adults are less sensitive to pain than younger adults

  • decreased sensitivity to pain can

    • help older adults cope with disease and injury

    • mask injuries and illnesses that need to be treated

  • high levels of pain were linked to memory impairment in older adults

• Perceptual Motor Coupling

  • decline in perceptual-motor skills in late adulthood makes driving a car difficult for many older adults

  • interventions to improve older adults’ driving

    • cognitive training

    • education

The Circulatory and Respiratory Systems

• cardiovascular disorders increase in late adulthood

• more than 70% of older adults who have a stroke or heart attack have preexisting hypertension

• consistent blood pressures above 120/80 should be treated to reduce the risk of heart attack, stroke, or kidney disease

• a rise in blood pressure with age can be linked to illness, obesity, stiffening of blood vessels, or lack of exercise

• various drugs, a healthy diet, and exercise can reduce the risk of cardiovascular disease

• diminished exercise capacity and lack of walking were the best predictors of earlier death in older adults with heart problems

• lung capacity drops 40% between the ages of 20 and 80, even when disease is not present

  • lungs lose elasticity, the chest shrinks, and the diaphragm weakens

  • older adults can improve lung functioning with diaphragm-strengthening exercises

  • severe impairments in lung functioning and death can result from smoking

Sexuality

• orgasm becomes less frequent in males with age

  • more direct stimulation usually is needed to produce an erection

• erectile dysfunction is common but advances in ed meds are helping these old men

• declining levels of serum testosterone is linked to ed

  • can be treated with testosterone replacement therapy to improve sexual functioing in males

  • benefit-risk ratio of trt is uncertain for older males

• a considerable proportion of older adults remain sexually active

• sexual activity declines through the later years of life

• older adults who didn’t have a partner were far less likely to be sexually active than those who did have a partner

  • for older adults with a partner who reported not having sex, the main reason was poor health (especially the male partner’s physical health)

  • older adults are increasingly using online dating sites

• sexual activity, a good-quality sexual life, and interest in sex were positively related to health in middle and late adulthood

  • aspects of secuality were higher for aging men than aging women, and the gap widens with age

  • sexually active life expectancy was longer for men than women

  • men lost more years of sexually active life due to poor health than women did

Health

Health Problems

• majority of adults who are still alive at 80 years of age are likely to have some type of impairment

• chronic diseases: those with a slow onset and a long duration

  • rare in early adulthood, increase in middle adulthood, and more common in late adulthood

  • arthritis is the most common in late adulthood, followed by hypertension

  • older women have a higher incidence of arthritis and hypertension and are more likely to have visual problems, but are less likely to have hearing problems than older men are

• chronic conditions associated with the greatest limitations on work are heart conditions, diabetes, asthma, and arthritis

• low income is strongly related to health problems in late adulthood

• Causes of Death in Older Adults

  • 60% of deaths in US adults 65-74 are caused by cancer or cardiovascular disease

  • cancer is leading case of death in US middle-aged adults

  • decline in cardiovascular disease has been attributed to improved drugs, decreased rates of smoking, improved diets, and increased exercise

  • cardiovascular disease is the leading cause of death in the 75-84 and 85+ age groups

  • ethnicity links

    • african americans have high death rates for stroke, heart disease, lung cancer, and female breast cancer

      • asian americans and latinos have low death rates for these diseases

    • in the last decade for most diseases in african americans, latinos, and asian american have decreased

    • death rates for most diseases remain high for african americans

• Arthritis

  • inflammation of the joints accompanied by pain, stiffness and movement problems

  • especially common in older adults

  • can effect hips, knees, fingers, and vertebrae

  • experience pain and stiffness, problems in moving, problems in performing routine daily activities

  • there is no known cure for arthritis but the symptoms can be reduced by meds

  • exercise also helps

• Osteoporosis

  • extensive loss of bone tissue

  • main reason many older adults walk with a marked stoop

  • women are especially vulnerable to osteoporosis

    • leading cause of broken bones in women

    • more common in non-Latina White, thin, and small-framed women

  • related to deficiencies in calcium, vitamin d, and estrogen, as well as a lack of exercise

  • aging women should get bone density checks

• Accidents

  • unintended injuries are the eighth leading cause of death among older adults

  • falls are the leading cause of injury deaths among adults who are 65+

Substance Use and Abuse

• in many cases, older adults are taking multiple meds, which can increase the risks associated with consuming alcohol or other drugs

• percentage of individuals who engaged in binge drinking declined considerable in middle and late adulthood but was highest among older adults

• substance abuse often goes undetected in older adults - illicit and prescription drugs

• late-onset alcoholism: onset of alcoholism after age 65

  • related to loneliness, loss of a spouse, or a disabling condition

• benefits of moderate drinking: better physical well-being and mental performance, greater openness to social contacts, increased ability to assert mastery over one’s life, greater volume in the brain’s hippocampus, reduced risk of cognitive impairment at 85

Exercise, Nutrition, and Weight

• Exercise

  • the more active older adults are, the healthier and happier they are likely to be

  • individuals who increased their fitness level from low to intermediate or high were at a lower risk for all-cause mortality

  • those who had exercise-related personal goals were four times more likely to report high exercise activity eight years later

  • resistance exercises can preserve and possible increase muscle mass in older adults

  • recommends 2 ½ hrs moderate-intensity aerobic activity per week and muscle strengthening activities 2+ days a week

  • exercise helps people to live independent lives with dignity in late adulthood

  • many older adults don’t engage in any exercise

  • in the US physical inactivity increases with age

  • it’s never too late to begin exercising and older adults can significantly benefit from regular exercise

• Nutrition and Weight

  • Healthy Nutrition

    • older adults usually decrease in snacking between meals, which contributes to harmful weight loss, especially in women

    • strategies for increasing weight gain in women: use of taste enhancers and calorie supplements between meals

  • Overweight and Obesity

    • substantial link between being overweight / obese and having a higher mortality risk

    • overweight adults live longer than normal-weight adults

    • being overweight is not a risk factor for earlier death, especially in older adults

    • being overweight was associated with lower all-cause mortality but being obese was associated with higher all-cause mortality

    • the majority of studies have revealed that being overweight is a risk factor for an earlier death

    • obesity is linked to the acceleration of diseases in many older adults

  • Calorie Restriction

    • calorie restriction in lab animals can increase the animals longevity

    • calorie restriction slows rna decline during the aging process

    • chronic problems with the cardiovascular system, kidneys, and liver appear at a later age when calories are restricted

    • calorie restriction may provide neuroprotection for the central nervous system

    • calorie restriction maintained more youthful functioning in the hippocampus

    • the research findings on the effects of calorie restriction in humans are mixed

  • The Controversy Over Vitamins and Aging

    • certain vitamin supplements (mainly antioxidants) might help to slow the aging process and improve the health of older adults

    • theory: antioxidants counteract the cell damage caused by free radicals, which are produced both by the body’s metabolism and by environmental factors

    • no link found between antioxidant vitamin intake and mortality but there is a link with a reduced risk of alzheimers

Health Treatment

• increasing demand for health services among the expanding population of older adults is likely to bring shortages of many types of health professionals

• older adults with health problems receive the recommended medical care they need only half the time

• the quality of health treatment provided to older adults needs to be significantly improved

• development of alternative home and community-based care has decreased the percentage of older adults who live in nursing homes

• as older adults age, their probability of being in a nursing home increases

• more than one-third of nursing homes and other extended-care facilities are seriously deficient

• many specialists in the health problems of the aged stress that home health care, elder-care centers, and preventative medicine clinics are good alternatives to nursing home care

  • less expensive

  • less likely to engender the feelings of depersonalization and dependency

  • increased demand for, but shortage of, home care workers

• important factor related to heath and survival in a nursing home is the patient’s feelings of control and self-determination