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Aging changes

Last updated: July 8, 2021

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Aging is the time-related progressive functional decline that affects all organ systems. It is believed to be caused by the accumulation of DNA damage, hormonal changes, and internally programmed cellular changes. Effects of aging include stiffening of the arteries and calcification of valves (cardiovascular system), osteoporosis and increased risk of fracture (musculoskeletal system), decreased chest wall compliance and increased ventilation-perfusion mismatch (respiratory system), susceptibility to recurrent infections and malignancies (immune system), and decline in cognitive function and changes in sleep patterns (nervous system).

All cells are subject to the natural processes of aging. Aging is believed to be caused by the accumulation of DNA damage, hormonal changes, and internally programmed cellular changes. Aging affects all organ systems and leads to progressive functional decline.

Aging changes in the bones, muscles, and joints

Regular exercise and a diet rich in protein, vitamin D, creatine, and omega-3 fatty acids are essential to ensure muscle growth and help prevent sarcopenia!

Aging changes in the skin

There is an increased incidence of:

Aging changes in the nails and hair

Aging changes in the cardiovascular system

Aging changes in the respiratory system [2]

Bodily changes Consequences
Weaker chest wall muscles
  • Chest wall stiffness ↓ chest wall compliance
Calcification of costochondral junctions
Osteoporosis-induced kyphosis
Decreased elastin in pulmonary parenchyma
  • ↓ Elastic recoil → lung compliance
Weakened baroreceptor/chemoreceptor response
  • Poor ventilatory response to ↓ O2 and ↑ CO2 levels
Weakened respiratory muscles
Weakened immune system
  • ↑ Susceptibility to infection

Aging changes in the genitourinary system

Aging changes in the immune system [3][4][5][6][7][8]

Among the elderly, a decreased immune response leads to an increased need for booster vaccinations.

Aging changes in the endocrine system

Aging changes in the nervous system [9]

  • Hearing impairments: presbycusis
  • Visual impairments
  • Decreased sense of smell and taste
  • Reduced ability to detect vibration, touch, temperature, and pressure changes (increased risk of pressure ulcers, hypothermia, and burns)
  • Decreased/absent deep tendon reflexes (e.g., ankle jerk reflex)
  • Decline in balance and gait stability (e.g., slow speed, reduced tandem gait ability)
  • Lower-extremity weakness
    • Delay in the onset of muscle activation due to a greater contraction of antagonistic muscles
    • Decline in the ability to develop joint torque using lower extremity muscles (e.g., compromised balance recovery during a postural disturbance)
    • Decline in physical function due to increased muscle tone, decreased muscle mass and increased muscle adiposity
  • Decreased cerebral blood flow and brain volume
  • Fluid intelligence declines, whereas crystallized intelligence increases
  • Altered sleep patterns in the elderly: early morning awakening, later sleep onset, decreased REM, and decreased slow-wave sleep
  • After the 6th decade of life
    • Decline in executive function, working memory, processing speed, and attention span
    • In most cases, no clinically significant impairment in social and occupational functioning
    • Increased suicide risk in case of physical and mental illnesses (particularly depression), functional impairment, and stressful life events (e.g., loss of a partner)

Falls in elderly individuals

  • Identification of risk factors: The risk for falls in elderly individuals is often multifactorial.
  • Individual risk assessment: Individuals who have fallen or with gait and balance deficits should undergo a risk assessment.
    • Past medical history; (e.g., history of previous falls, circumstances of the falls, current medication)
    • Physical examination including postural vital signs, visual acuity, cognitive, neurological, musculoskeletal, and hearing function tests
    • Postural stability tests
      • Timed Up and Go test
        • The individual is asked to get up from a chair, walk a certain distance, turn around, walk back, and sit down again.
        • Used to assess musculoskeletal function and postural stability in a patient who has fallen.
      • Performance-oriented mobility assessment
        • Evaluates an individual's balance abilities in a chair, standing, and dynamic balance during gait (e.g., gait initiation, step continuity and path deviation when asked to walk, trunk position, ability to maintain balance when someone slightly pulls on the individual)
        • Used to assess balance and gait
  • Preventive measures
    • Minimize the number of medications that may contribute to falls (See “Beers criteria” for details).
    • Physical therapy
    • Elimination of potential hazards in the individual's home environment
  1. John D. Furber. Extracellular Glycation Crosslinks: Prospects for Removal. Rejuvenation Research. 2006; 9 (2): p.274-278. doi: 10.1089/rej.2006.9.274 . | Open in Read by QxMD
  2. Sharma G, Goodwin J. Effect of aging on respiratory system physiology and immunology.. Clinical interventions in aging. 2006; 1 (3): p.253-60.
  3. Watad A, Bragazzi NL, Adawi M, et al. Autoimmunity in the elderly: Insights from basic science and clinics - A mini-review. Gerontology. 2017; 63 (6): p.515-523. doi: 10.1159/000478012 . | Open in Read by QxMD
  4. Eisen HN. Affinity enhancement of antibodies: How low-affinity antibodies produced early in immune responses are followed by high-affinity antibodies later and in memory B-cell responses. Cancer Immunol Res. 2014; 2 (5): p.381-392. doi: 10.1158/2326-6066.cir-14-0029 . | Open in Read by QxMD
  5. Montecino-Rodriguez E, Berent-Maoz B, Dorshkind K. Causes, consequences, and reversal of immune system aging. J Clin Invest. 2013; 123 (3): p.958-965. doi: 10.1172/jci64096 . | Open in Read by QxMD
  6. Mehr R, Melamed D. Reversing B cell aging. Aging. 2011; 3 (4): p.438-443. doi: 10.18632/aging.100313 . | Open in Read by QxMD
  7. Bulati M, Caruso C, Colonna-Romano G. From lymphopoiesis to plasma cells differentiation, the age-related modifications of B cell compartment are influenced by “inflamm-ageing”. Ageing Res Rev. 2017; 36 : p.125-136. doi: 10.1016/j.arr.2017.04.001 . | Open in Read by QxMD
  8. Kogut I, Scholz JL, Cancro MP, Cambier JC. B cell maintenance and function in aging. Semin Immunol. 2012; 24 (5): p.342-349. doi: 10.1016/j.smim.2012.04.004 . | Open in Read by QxMD
  9. Seraji-Bzorgzad N, Paulson H, Heidebrink J. Neurologic examination in the elderly. Elsevier ; 2019 : p. 73-88
  10. Hiroaki Oguro, Kazunori Okada, Nobuo Suyama, Kazuya Yamashita, Shuhei Yamaguchi, Shotai Kobayashi. Decline of vertical gaze and convergence with aging. Gerontology. 2004 .