Chapter 1
 Introduction - Outline
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I. Why study aging?
     A. Personal and professional reasons
     B. Population trends
          1. Rapid increase in number of elders
          2. Rapid increase in proportion of elders in total population
          3. Projected continued increases
          4. Reasons for increases in elders
               a. High birth rates before 1920 and 1946-64
               b. High number of births 1946-64
               c. Decline in infant death rates
               d. Increasing life expectancies at all ages including adults
          5. Baby boomers
          6. Diverse importance of elder demographics
II. What is aging?
     A. Definitions
          1. Developmental changes
          2. Physiological changes
          3. Development
               a. Embryology
               b. Maturation
               c. Aging - age changes
               d. Senescence
     B. Types of aging
          1. Biological aging
               a. Definition
               b. Importance of cells
               c. Importance of homeostasis
               d. Ways of keeping homeostasis
                    (1) Preventing change - barriers and insulators
                    (2) Stopping/reversing - negative feedback
                         (a) Detecting change
                         (b) Communicating information
                         (c) Making adjustment
               e. Effects of aging on keeping homeostasis
                    (1) Weaker barriers and insulators
                    (2) Weaker steps in negative feedback systems
                    (3) Greater speed, number and degree of deviations from homeostasis
          2. Chronological aging
          3. Cosmetic aging
          4. Social aging
          5. Psychological aging
          6. Economic aging
          7. Interactions among types of aging
     C. What aging is not
          1. Abuse, misuse, disuse, disease
          2. Reasons for age-related increase in disease
               a. Timing of genetic diseases
               b. Age-related decline in homeostatic mechanisms
               c. Compensatory strategies
               d. Slow development of some diseases
               e. Gradual loss of reserve capacity
               f. Increased exposures to causes of disease
          3. Importance of prevention
          4. Importance of early detection and treatment
III. Why study biological aging?
     A. Distinguishing age changes from age-related changes
     B. Implementing appropriate prevention and treatment
     C. Evaluating prevention and treatment
     D. Increasing predictability
IV. How is biological aging studied?
     A. Cross-sectional method
          1. Design of method (age categories, measurements, analyzes)
          2. Advantages
               a. Fast
               b. Many subjects
               c. No period effect
          3. Disadvantages
               a. Birth-cohort effect - inferring age changes
               b. Differential mortality - biased results
               c. Cannot detect changes in individuals
               d. Errors in results
          4. Time-lag study
     B. Longitudinal method
          1. Design method (repeat measurements on same individuals)
          2. Advantages
               a. Measures changes over time
               b. Can detect changes in individuals
               c. Can evaluate interactions between aging and other changes
               d. Increases predictability
          3. Disadvantages
               a. Requires much time
               b. Changes in techniques and participants
               c. Expensive
               d. Period effect - influence of historical period
               e. Birth cohort effect
               f. Practice effect
          4. Baltimore Longitudinal Study of Aging (BLSA)
     C. Cross-sequential method
     D. Non-human studies
          1. Advantages
          2. Disadvantages
V. What we know thus far
     A. What happens during biological aging?
          1. When aging begins
          2. Why aging appears after it begins
               a. Reserve capacity
               b. Compensatory mechanisms
          3. Types of variability in aging (onset and rate)
               a. Among individuals
               b. Among body parts within one person
               c. At different ages and times
               d. Effects from genes and environmental factors
          4. Heterogeneity among elders
           a. Reasons for increases
           b. Importance of increases
      5. The concept of biological age
           a. Methods of measurement
           b. Importance
           c. Controversies
     B. Life expectancy
          1. Maximum longevity (XL)
               a. Definition
               b. Human maximum longevity
               c. Altering maximum longevity
          2. Mean longevity (ML) and life expectancy
               a. Definition
               b. Mean longevity at birth
                    (1) Effects of period of history
                    (2) Effects of sex and race
               c. Mean longevity at other ages
               d. Specific factors affecting mean longevity
                    (1) Less modifiable factors
                    (2) More modifiable factors
          3. Status of the individual
     C. Quality of life
          1. Methods for evaluation
          2. Importance of evaluation

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©Copyright 1999 - Augustine G. DiGiovanna - All rights reserved.
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