ch05 nutrition and theories of aging

Theories of AgingTheories of Aging

Copyright ©2010 by Pearson Education, Inc.Upper Saddle River, New Jersey 07458

All rights reserved.

Gerontological Nursing, Second EditionPatricia A. Tabloski

ObjectivesObjectives

• This presentation will describe aging from both a biological/physiological and a psychosocial perspective.

• Biological/physiological theories will be presented in two main categories, program theories and error theories.

• Psychosocial theories will be discussed in two main categories, full-life theories and mature-life theories.




What is Aging?What is Aging?

The gradual and spontaneous changes that occur in maturation from infant to young adult. These changes create a normal physiologic decline seen in middle and late adulthood.

• Changes during puberty

• Graying of hair




SenescenceSenescence

The process by which a cell looses its ability to divide, grow, and function. This loss of function ultimately ends in death.

• A degenerative process, only.

• Has no positive features.





“The link between genes and lifespan is unquestioned. The simple observation that some species live longer than others -- humans longer than dogs, tortoises longer than mice -- is one convincing piece of evidence.”

The National Institute on Aging





• All aging begins with genetics

• Aging changes the biochemical and physiological processes in the body

• Cell and molecular biologists examine and propose theories to explain the aging process– What causes aging?– How can you influence aging …prolong life?




The Two Main Aging Theory The Two Main Aging Theory CategoriesCategories

• Programmed TheoriesAging has a biological timetable or internal biological clock.

• Error TheoriesAging is a result of internal or external assaults that damage cells or organs so they can no longer function properly.

Many theories are a combination of programmed and error theories.




Programmed vs. Error TheoriesProgrammed vs. Error Theories

Programmed Theories

• Programmed Senescence Theory

• Endocrine Theory• Immunology Theory

Error Theories• Wear and Tear Theory• Rate-of-Living Theory• Cross-linking Theory• Free Radical Theory• Error

CatastropheTheory• Somatic Mutation

Theory

Programmed TheoriesProgrammed Theories

Programmed Senescence Theory

Endocrine Theory

Immunology Theory




Programmed Senescence TheoryProgrammed Senescence Theory

• The result of sequential switching “off” or “on” of specific genes.




Telomeric Theory Telomeric Theory

• Telomeres are specialized DNA sequences at the end of chromosomes.– They shorten with each cell division.– When the telomeres become too short, the cell enters

the senescence stage.

• In the normal process of DNA replication, the end of the chromosome is not copied exactly, which leaves an unreplicated gap.




Telomeric TheoryTelomeric Theory• The enzyme, telomerase, fills the gap by

attaching bases to the end of the chromosomes.

• As long as the cells have enough telomerase to do the job, they keep the telomeres long enough to prevent any important information from being lost as they go through each replication.– With time, telomerase levels decrease.– With decreasing telomerase levels, the

telomeres become shorter and shorter.




Telomeric TheoryTelomeric Theory

Shortened telomeres are found in:– Atherosclerosis – Heart disease– Hepatitis– Cirrhosis




Telomeric Theory and CancerTelomeric Theory and Cancer

• 90% of cancer cells have been found to possess telomerase.– Telomerase prevents the telomere from

shortening.– This allows the cancer cells to reproduce, resulting

in tumor growth.

• Research areas– Measuring telomerase may help detect cancer.– Stopping telomerase may fight cancer by causing

death of cancer cells.– Telomerase may be used to help with wound

healing or the immune response.




Endocrine TheoryEndocrine Theory

• Biological clocks act through hormones to control the pace of aging. Hormones effects growth, metabolism, temperature, inflammation and stress.

• Examples- Menopause– Decreased level of estrogen & progesterone– Hot flashes, insomnia




Immunologic TheoryImmunologic Theory

• A programmed decline in the immune system leads to an increased vulnerability to disease, aging and death

• Example- Decreased T cells (helper cells) in adults– Increased diseases in older adults– Increased autoimmune diseases in adults

Error TheoriesError TheoriesWear and Tear Theory Error

Free Radical Theory

Rate-of-Living Theory CatastropheTheory

Cross-linking Theory

Somatic Mutation Theory




Wear and Tear TheoryWear and Tear Theory

• Years of damage to cells, tissues and organs eventually wears them out, killing both them and the body

• Example- Wearing out of the skeletal system such as in osteoarthritis

• Wear and tear can be viewed as a result of aging and not the cause of it.




Rate-of-Living TheoryRate-of-Living Theory• The greater an organism’s basal metabolic

rate, the shorter the life span.• Free radicals or other metabolic by-

products play a role in senesce.• Example

Animals with the most rapid metabolisms tend to have the shortest lifespans, i.e, birds have a shorter lifespan than humans.

• Studies examining the relationship between metabolic rates and longevity have produced inconsistent results, limiting the usefulness of this theory.




Cross-Linking TheoryCross-Linking Theory

• The accumulation of cross-linked proteins damages cells and tissue, slowing down bodily processes.

• ExampleNon-enzymatic glycosylation reactions occur when glucose molecules attach to proteins causing a chain of chemical reactions resulting in a structural change to the proteins.– Loss of flexibility of connective tissue– Microvascular changes in arteries




Free Radical TheoryFree Radical Theory

• During aging, damage produced by free radicals cause cells and organs to stop functioning.

• A free radical is a molecule with an unpaired, highly reactive electron. One type of very reactive free radical is the oxygen free radical, which may be produced during metabolism or as a result of environmental pollution.

Oxygen free radicals are formed in your cells, naturally, during the oxidation of food to water and carbon dioxide.





The free radical “grabs” a electron from any molecule in its vicinity.

It does this because electrons like to exist in pairs.

When it “grabs” an electron from another molecule, it damages the other molecule.





• Some of the molecules that may be damaged by free radicals are fats, proteins, and DNA (both in the nucleus and in mitochondria).

• If membrane fats are attacked, then you get the breakdown of the cell membrane. If it is a red blood cell membrane, you get hemolysis.

• If proteins are attacked, you get the breakdown of proteins, which may result in the loss of biological function and the accumulation of “catastrophic” compounds.

• If DNA is attacked, you will get a mutation that may cause aging or cancer.





• Under normal conditions, your natural defense mechanisms prevent most of the oxidative damage from occurring.

• The free radical theory of aging proposes that, little-by-little, small amounts of damage accumulate and contribute to deterioration of tissues and organs.





For example, when Vitamin E “scavenges” free radicals, it becomes a free radical and may be more carcinogenic than the original free radical.

This is the reason why taking high doses of vitamin E SUPPLEMENTS appears to INCREASE cancer risk in a person, not decrease cancer risk.




Catastrophe TheoryCatastrophe Theory

• Any damage to the enzyme systems that synthesize proteins in the body results in faulty protein synthesis.

• The faulty proteins continue to accumulate in the cell until they reach a level that damages the cells, tissues, and organ

• When enough damage accumulates, this may result in cell malfunctioning ( aging) leading to death.




Somatic Mutation Somatic Mutation

• Genetic mutations occur and accumulate with age in the somatic cell causing the cell to:– Deteriorate– Malfunction

• Accumulation of mutations result in :– Damage to the DNA

The theory states that aging is an imbalance between DNA’s ability to repair itself and accumulating DNA damage.

– When the damage exceeds the repair, the cell malfunctions and this can lead to senesence.

Psychological Theories of Psychological Theories of AgingAging




Psychological Theories of AgingPsychological Theories of Aging

1. Full-Life Development Theories (Erikson’s Theory will be the only one discussed.)

2. Mature-Life Theories1. Robert Peck’s Theory2. The Activity Theory (Neugarten’s Theory will

be the only one discussed.)3. The General Theory of Disengagement




Full-Life Development Theory Full-Life Development Theory

Eric Erickson was one of the first psychological theorists to develop a personality theory that extends to old age.




Full-Life Development TheoryFull-Life Development TheoryMajor ConceptsMajor Concepts

• The ego is a positive driving force for development.– The ego’s job is to establish and maintain

identity.– A lack of identify leads to lack of direction and

non-productivity.

• There are stages of personality and ego development.





• The last stages are “Adulthood” & “Late Life Stage.”

• “Adulthood” is characterized by a struggle between “Generativitiy” and Stagnation.

• “Generativity”– Giving back to society by raising children– Being productive at work– Being involved in the community – Guiding, parenting, and monitoring the next

generation





• Stagnation– Being unproductive– Feeling anger, hurt and self absorption

• As one becomes mature, there is a struggle between “Ego Integrity” & despair

• “Ego Integrity”– Exploring life as a retired person who is not identified

with an occupation– Contemplating accomplishment – Feeling life is successful




Full-Life Development TheoryFull-Life Development Theory

• Despair– Feeling guilt about the past– Not accomplishing life goals– The final pathway:

dissatisfied despair

depression hopelessness

Mature-Life TheoriesMature-Life Theories





NeugartenNeugartenBernice Neugarten describes tasks that must be accomplished for successful aging. Some of these tasks include:

• Accepting reality and the imminence of death.

• Coping with physical illness.

• Accepting the necessity of being dependent on outside support while still making independent choices that can give satisfaction.





NeugartenNeugarten

A person must remain as active as possible. This falls under the category of “activity theory.”





General Theory of DisengagementGeneral Theory of DisengagementThis theory is controversial and has these

features:• Both older people and society mutually withdraw

from each other.• A person gradually disconnects from other people

in anticipation of death.• Intrinsic changes in personality occur which allow

a person to psychologically withdraw from society’s expectations.

Note: This is the opposite of “Activity Theory.”




SummarySummary

This presentation has described aging from both a biological/physiological and a psychosocial perspective.

Biological/physiological theories are divided into two main categories, program theories and error theories.

Psychosocial theories are divided into two main categories, full life theories and mature life theories.




The EndThe End



CHAPTER


Nutrition and Aging

5Lecture Note PowerPoint Presentation




LEARNING OUTCOME 1

Describe the normal changes of aging in body composition and digestion, absorption,

and metabolism of nutrients.




Causes of Sarcopenia (Excessive Loss of Lean Muscle Mass)

• Disability or disease

• Sedentary (inactive) lifestyle

• Decreased anabolic hormone production

• Increased cytokine activity

• Decreased nutrition• Cytokine: Any of several regulatory proteins, such as the interleukins and

lymphokines, that are released by cells of the immune system and act as intercellular mediators in the generation of an immune response.




Effects of Loss of Muscle Function

• Functional decline in strength and endurance

• Predisposition to falls

• Lower total body water (TBW)




At Age 65, 33.1% of Adults are Edentulous (having lost teeth)having lost teeth)

• Effects amounts and types of foods consumed




Saliva Production Declines (Xerostomia)

• Hindered taste and swallowing




Atrophic Gastritis

• Reduction in stomach size

• Reduction in size and number of glands and mucous membranes




Achlorhydria (Lack of Hydrochloric Acid)

• Impaired absorption of B12 and iron– Reduced gastric production of intrinsic factor

can also impair B12 absorption




Constipation Reduces Intake and Can Be Caused by

• Slowed intestinal peristalsis

• Inadequate intake of fluid and fiber

• Illness or medications

• Sedentary lifestyle




Causes of Increased Risk of Uncompensated Dehydration

• Altered thirst mechanism

• Impaired angiotensin




Dehydration Risks Increase as a Result of Voluntary Fluid Restriction Due to

• Incontinence

• Nocturia

• Need for assistance with toileting

• Cognitive or physical limitations– Inadequate access to free fluids– Thirst dysregulation




Sensory Changes

• Impact the ability to obtain, prepare, and enjoy food




Causes of Altered Nutritional Adequacy

• More sedentary lifestyle

• Social isolation

• Changes in economic status




LEARNING OUTCOME 2

Differentiate between normal and disease-related changes in risk factors for undernutrition in the older person.




How Chronic Disease Impacts Nutritional Status

• Changes in nutritional needs

• Therapeutic diets

• Changes in nutrient utilization and absorption

• Medication side effects– Impact on appetite and taste– Decreased saliva– Gastrointestinal side effects




LEARNING OUTCOME 3

Identify normal nutrition requirements of the older person.




Nutritional Dietary Standards

• Provide nutritional recommendations

• Work well as an assessment tool

• Types– Dietary reference intakes

Provide specific nutrient recommendations Recommended dietary allowances (RDAs) Adequate intakes (AIs) Tolerable upper limits (TULs)

– Food Guide Pyramid




Differences in Dietary Reference Intake (DRI) for the Older Adult Versus General Adult Population

• Vitamin D

• Calcium

• Vitamin B12

• Vitamin B6

• Energy




Recommended Dietary Allowance for the Older Person

• Protein 0.8 g/kg body weight




DRI for Energy, or Estimated Energy Requirements (EER), Based On

• Gender

• Age

• Body mass index (BMI)

• Activity level




EER Adjusts for Age to Account for Losses in Lean Muscle Mass and Diminished Physical Activity

• Following the lowest daily recommended values for all the food groups will result in approximately 1,600 kcal of energy




Figure 5-1Modified MyPyramid for the older adult.

Source: Copyright 2007 Tufts University. Reprinted with permission from Lichtenstein, A. H., Rasmussen, H., Yu, W. W., Epstein, S. R., and Russell, R. M. (2008). Modified MyPyramid for Older Adult. J Nutr. 2008, 138, 78–82.




Vitamin D

• The Adequate Intake (AI) for vitamin D triples from young adulthood to age 71

• Adults over age 70 require 600 IU of vitamin D

• AI for adults aged 51 to 70 is 400 IU • Tolerable Upper Limit (TUL) of vitamin D is

2,000 IU• The Modified Food Guide Pyramid

recommends a supplement of vitamin D and three dairy servings per day




Calcium

• AI for in adults over 50 years of age is 1,200 mg

• Modified Food Guide Pyramid recommends three dairy servings daily plus a calcium supplement

• TUL is 2,500 mg




Vitamin B12

• Recommended Dietary Allowance (RDA) is 2.4 mcg

• Dietary Reference Intakes (DRI), Modified Food Guide Pyramid, and U.S. Dietary Guidelines recommend B12-fortified foods or a vitamin B12 supplement




Vitamin B6

• DRI for adults over age 50 is 1.5 mg per day for women and 1.7 mg per day for men

• TUL is 100 mg




Fluid Needs

• Total daily water recommendation for adults over age 51 is 3.7 L for men and 2.7 L for women

• RDA based on a general water requirement of 1.0–1.5 ml/cal of energy intake




Fluid Needs

• Modified Food Guide Pyramid recommends 8 cups of water as pyramid foundation

• Do not include alcohol and caffeinated beverages in fluid calculations




LEARNING OUTCOME 4

Outline the causes and consequences of undernutrition in the older person.




Physical and Psychological Causes for Insufficient Intake

• Reduced access

• Rear of incontinence

• Dependence for toileting or feeding

• Depression or cognitive impairment

• Polypharmacy

• Pain

• Chronic diseases

• Dysphagia




Physical and Psychological Causes for Insufficient Intake

• Sensory changes

• Diet– Preferences– Unfamiliarity– Medically restricted diets

• Finances– Quality– Quantity




Box 5-5Causes of Unintentional Weight Loss




Hypermetabolism

• Chronic illnesses

• Fever

• Wounds

• Infection

• Fractures




Nutrient Losses

• Malabsorption or high output from diseases or treatments




Consequences of Undernutrition

• Impact quality and quantity of life, and morbidity and mortality– Poor wound healing– Skeletal muscle loss– Functional decline– Altered immune response– Altered pharmacokinetics– Increased risk of institutionalization




LEARNING OUTCOME 5

Identify tools and parameters used to assess nutritional status.




Comprehensive Nutritional Assessment Reviews

• Anthropometric measurements

• Laboratory values

• Clinical findings from the physical examination

• Patient history




Anthropometric Measurements Include Scientific Measurement of

• Height

• Weight

• Weight history

• Body mass index (BMI)

• Muscle mass

• Fat mass




Laboratory Parameters Used to Assess Nutritional Status

• Albumin• Transferrin • Complete blood count (CBC)

– Mean cell volume (MCV)– Hemoglobin– Hematocrit

• Serum folate • B12 assays




Nursing Assessment Findings May Indicate

• Existing nutritional problems

• Risk factors for undernutrition




Nutritional History Assessment

• 24-hour diet recall

• Food frequency assessment

• 3-day food record (2 weekdays and 1 weekend day)




Screening Tools

• Nutritional Screening Initiative (NSI)

• DETERMINE checklist

• Mini Nutritional Assessment

• Minimum Data Set (MDS)




LEARNING OUTCOME 6

Define appropriate nursing interventions and treatment for nutrition-related problems of

the older person.




Skin Assessment

• Turgor

• Lesions

• Wound healing

• Color variations

• Dryness and cracking

• Oral mucous membranes for hygiene, coatings, and fissures




Hair Assessment

• Distribution and condition




Abdominal Assessment

• Firmness

• Tenderness

• Bowel patterns




Pain Assessment

• Levels of pain

• PRN medications prior to dining




Eating or Drinking Assessment

• Dysphagia

• Positioning

• Need for adaptive equipment




Dining Environment Assessment

• Small, frequent meals

• Avoid distractions and delays

• Pay attention to sights, sounds, and smells

• Include family members




Review of Medications Potentially Causing

• Anorexia

• Depression

• Early satiety

• Taste alterations

• Lethargy

• Appetite suppression




Common Offending Medications

• Digoxin

• Diuretics

• Chemotherapy

• Antibiotics

• Antidepressants




Nursing Interventions

• Individualized nutritional care plans

• Feeding assistance

• Altering the physical environment

• Liberalizing restrictive diets

• Collaborating with registered dieticians

• Making appropriate referrals




LEARNING OUTCOME 7

Identify current dietary approaches to chronic disease in the older person.




Weight Loss and Sodium Restriction May Benefit

• Sleep apnea

• Osteoarthritis

• Hypertension




Taste Deficits

• Provide saltier or sweeter foods




Visual Deficits

• Use the face of a clock for plate food locations

ch05 nutrition and theories of aging

Documents

upper saddle

lean muscle

free radical

free radical

free radicals

telomeric

general theory

activity theory