Age Related Changes

Age-associated changes are most pronounced in advanced age of 85 years or older, may alter the older person’s response to illness, show great variability among individuals, are often impacted by genetic and long-term lifestyle factors, and commonly involve a decline in functional reserve with reduced response to stressors.


Gerontological changes are important in nursing assessment and care because they can adversely affect health and functionality and require therapeutic strategies; must be differentiated from pathological processes to allow development of appropriate interventions; predispose to disease, thus emphasizing the need for risk evaluation of the older adult; and can interact reciprocally with illness, resulting in altered disease presentation, response to treatment, and outcomes.


A.  Definition

  1. Isolated systolic hypertension: Systolic BP 140 mmHg and diastolic BP 90 mmHg

B.  Etiology

  1. Arterial wall thickening and stiffening, decreased compliance
  2. Left ventricular and atrial hypertrophy; sclerosis of atrial and mitral valves
  3. Strong arterial pulses, diminished peripheral pulses, cool extremities

C.  Implications

  1. Decreased cardiac reserve
    • At rest: No change in heart rate, cardiac output
    • Under physiological stress and exercise: Decreased maximal heart rate and cardiac output, resulting in fatigue, shortness of breath, slow recovery from tachycardia
    • Risk of isolated systolic hypertension; inflamed varicosities
    • Risk of arrhythmia, postural, and diuretic-induced hypotension; may cause syncope

D.  Parameters of cardiovascular assessment

  1. Cardiac assessment: EKG; heart rate, rhythm, murmurs, heart sounds; palpate carotid artery and peripheral pulses for symmetry (Bush, 2016)
  2. Assess BP (lying, sitting, and standing) and pulse pressure (Bettelli, 2018; Butt & Harvey, 2015)


A.  Etiology

  1. Decreased respiratory muscle strength; stiffer chest wall with reduced compliance
  2. Diminished ciliary and macrophage activity, drier mucous membranes; decreased cough reflex
  3. Decreased response to hypoxia and hypercapnia

B.  Implications

  1. Reduced pulmonary functional reserve
    • At rest: No change
    • With exertion: Dyspnea, decreased exercise tolerance
  2. Decreased respiratory excursion and chest/lung expansion with less effective exhalation; respiratory rate of 12 to 24 breaths per minute
  3. Decreased cough and mucus/foreign matter clearance
  4. Increased risk of infection and bronchospasm with airway obstruction

C.  Parameters of pulmonary assessment

  1. Assess respiration rate, rhythm, regularity, volume, depth (Bush, 2016), and exercise capacity (Hassel et al., 2015). Ascultate breath sounds throughout lung fields (Mick & Ackerman, 2004).
  2. Inspect thorax appearance, symmetry of chest expansion. Obtain smoking history.
  3. Monitor secretions, breathing rate during sedation, positioning (Clayton, 2008;), arterial blood gases, pulse oximetry (Bush, 2016).

D.  Nursing care strategies

  1. Maintain patent airways through upright positioning/repositioning (Clayton, 2008).
  2. Provide oxygen as needed (Tran et al., 2018); maintain hydration and mobility (Miller, 2015).
  3. Assess incentive spirometry as indicated, particularly if immobile or declining in function (Cao et al., 2017; Clayton, 2008).
  4. Educate patient on cough enhancement (Cao et al., 2017), smoking cessation (NCCDPHP Office on Smoking and Health, 2014).


A.  Definitions

  1. To determine renal function (GFR):
    • Cockcroft–Gault equation: Calculation of creatinine clearance in older adults (Péquignot et al., 2009). For men:

  Cockcroft-Gault Equation: Men

For women, the calculated value is multiplied by 85% (0.85).

MDRD: See National Kidney Disease Education Program calculator (National Kidney Disease Education Program, 2012).

B.  Etiology

  1. Decreases in kidney mass, blood flow, GFR (10% decrement/decade after age 30 years); decreased drug clearance
  2. Reduced bladder elasticity, muscle tone, capacity
  3. Increased postvoid residual, nocturnal urine production
  4. In males, prostate enlargement with risk of BPH

C.  Implications

  1. Reduced renal functional reserve; risk of renal complications in illness
  2. Risk of nephrotoxic injury and adverse reactions from drugs
  3. Risk of volume overload (in heart failure), dehydration, hyponatremia (with thiazide diuretics), hypernatremia (associated with fever), and hyperkalemia (with potassium-sparing diuretics); reduced excretion of acid load
  4. Increased risk of urinary urgency, incontinence (not a normal finding), UTI, nocturnal polyuria; potential for falls

D.  Parameters of renal and genitourinary assessment

  1. Assess renal function (GFR through creatinine clearance; Lederer & Nyak, 2017; National Kidney Disease Education Program, 2012; Péquignot et al., 2009).
  2. Assess choice/need/dose of nephrotoxic agents and renally cleared drugs (Cutler & Clark, 2018; see Chapter 24, Reducing Adverse Drug Events in the Older Adult).
  3. Assess for fluid/electrolyte and acid/base imbalances (Miller, 2015).
  4. Evaluate nocturnal polyuria, urinary incontinence, and BPH (Lederer & Nayak, 2017). Assess UTI symptoms (see “Atypical Presentation of Disease” section; Rowe & Juthani-Mehta, 2017).
  5. Assess fall risk if nocturnal or urgent voiding (see Chapter 19, Late Life Depression).

E.  Nursing care strategies

  1. Monitor nephrotoxic and renally cleared drug levels (Cutler & Clark, 2018).
  2. Maintain fluid/electrolyte balance (Bettelli, 2018). Minimum ingestion of 1,500 to 2,500 mL/d from fluids and foods for 50- to 80-kg adults to prevent dehydration (Miller, 2015).
  3. For nocturnal polyuria, limit fluids in evening, avoid caffeine, use prompted-voiding schedule (Lederer & Nayak, 2017).
  4. Institute fall prevention strategies for nocturnal or urgent voiding (see Chapter 19, Late Life Depression)


A.  Definition(s)

  1. BMI: Healthy, 18.5 to 24.9 kg/m2; overweight, 25 to 29.9 kg/m2; obese, 30 kg/m2 or greater

B.  Etiology

  1. Decreases in strength of muscles of mastication, taste, and thirst perception
  2. Decreased gastric motility with delayed emptying
  3. Atrophy of protective mucosa
  4. Malabsorption of carbohydrates, vitamins B12 and D, folic acid, calcium
  5. Impaired sensation to defecate
  6. Reduced hepatic reserve; decreased metabolism of drugs

C.  Implications

  1. Risk of chewing impairment, fluid/electrolyte imbalances, poor nutrition
  2. Gastric changes: Altered drug absorption, increased risk of GERD, maldigestion, NSAID-induced ulcers
  3. Constipation not a normal finding; risk of fecal incontinence with disease (not in healthy aging)
  4. Stable liver function tests; risk of adverse drug reactions

D.  Parameters of oropharyngeal and gastrointestinal assessment

  1. Assess abdomen, bowel sounds.
  2. Assess oral cavity (see Chapter 8, Sensory Changes in the Older Adult); chewing and swallowing capacity, dysphagia (coughing, choking with food/fluid intake; Landi et al., 2017). If aspiration occurs, assess lungs (rales) for infection and typical/atypical symptoms (High, 2017; Mandell et al., 2007; see “Atypical Presentation of Disease” section,
  3. Monitor weight, calculate BMI, and compare to standards (Lichtenstein et al., 2006). Determine dietary intake and compare to nutritional guidelines (USDA & USDHHS, 2015; Visvanathan & Chapman, 2009; see Chapter 10, Assessment of Physical Function in the Older Adult).
  4. Assess for GERD, constipation and fecal incontinence, and fecal impaction by digital examination of rectum or palpation of abdomen.

E.  Nursing care strategies

  1. Monitor drug levels and liver function tests if on medications metabolized by liver. Assess nutritional indicators (USDA & USDHHS, 2015; Visvanathan & Chapman, 2009).
  2. Educate patient on lifestyle modifications and OTC medications for GERD.
  3. Educate patient on normal bowel frequency, diet, exercise, and recommended laxatives. Encourage mobility, and provide laxatives if on constipating medications (Mounsey et al., 2015).
  4. Encourage participation in community-based nutrition programs (Visvanathan & Chapman, 2009); educate on healthful diets (USDA & USDHHS, 2015).


A.  Definition

Sarcopenia: Reduced muscle mass, physical performance, and grip strength associated with aging

B.  Etiology

  1. Sarcopenia evokes increased weakness and poor exercise tolerance
  2. Lean body mass replaced by fat with redistribution of fat
  3. Bone loss in women and men after peak mass at age 30 to 35 years
  4. Decreased ligament and tendon strength; intervertebral disc degeneration; articular cartilage erosion; changes in stature with kyphosis, height reduction

C.  Implications

  1. Sarcopenia: Increased risk of disability, falls, unstable gait (Ko et al., 2018)
  2. Risk of osteopenia and osteoporosis
  3. Limited ROM, joint instability, risk of osteoarthritis

D.  Nursing care strategies

  1. Encourage physical activity through health education and goal setting (Fuggle et al., 2017) to maintain function (Chodzko-Zajko et al., 2009).
  2. Administer pain medication to enhance functionality (see Chapter 18, Preventing Functional Decline in the Acute Care Setting). Implement strategies to prevent falls (see Chapter 19, Late Life Depression and Chapter 23, Assessing, Managing, and Preventing Falls in Acute Care).
  3. Prevent osteoporosis by adequate daily intake of calcium and vitamin D, physical exercise, and smoking cessation (Bijelic et al., 2017; NCCDPHP Office on Smoking and Health, 2014). Advise routine bone mineral density screening (AHRQ, 2014; Curry et al., 2018).


A.  Etiology

  1. Decrease in neurons and neurotransmitters
  2. Modifications in cerebral dendrites, glial support cells, synapses
  3. Compromised thermoregulation

B.  Implications

  1. Impairments in general muscle strength, deep tendon reflexes, nerve conduction velocity; slowed motor skills and potential deficits in balance and coordination
  2. Decreased temperature sensitivity; blunted or absent fever response
  3. Slowed speed of cognitive processing. Some cognitive decline is common but not universal. Most memory functions are adequate for normal life
  4. Increased risk of sleep disorders, delirium, neurodegenerative diseases

C.  Parameters of nervous system and cognition assessments

  1. Assess, with periodic reassessment, baseline functional status (Cholerton et al., 2017; see Chapter 9, Assessing Cognitive Function in the Older Adult, Chapter 10, Assessment of Physical Function in the Older Adult, and Chapter 19, Late Life Depression). During acute illness, monitor functional status and delirium (see Chapter 17, Advance Care Planning).
  2. Evaluate, with periodic reassessment, baseline cognition and sleep disorders (Moraes et al., 2014).
  3. Assess impact of age-related changes on level of safety and attentiveness in daily tasks (Klaming et al., 2017).
  4. Assess temperature during illness or surgery (Kuchel, 2017).

D.  Nursing care strategies

  1. Institute fall-prevention strategies (see Chapter 19, Late Life Depression).
  2. To maintain cognitive function, encourage lifestyle practices of regular physical exercise (Harada et al., 2013) intellectual stimulation (Puglielli & Mattson, 2017), and healthful diet (Schwingshackl, et al., 2018).
  3. Recommend behavioral interventions for sleep disorders.


A.  Etiology

  1. Immune response dysfunction, reduced efficacy of vaccinations (Liang, 2016), and chronic inflammatory state (Hunt et al., 2010).

B.  Nursing care strategies

  1. Follow CDC immunization recommendations for the older adult for pneumococcal infections, seasonal influenza, zoster, tetnaus, and hepatitis (CDC, 2018: High 2017).


A.  Etiology

  1. Diseases, especially infections, may manifest with atypical symptoms in older adults.
  2. Symptoms/signs are often subtle and include nonspecific declines in function or mental status, decreased appetite, incontinence, falls (Liang, 2016), fatigue, and exacerbation of chronic illness (Gentleman, 2014; High, 2017).
  3. Fever blunted or absent in very old (High, 2017), frail, or malnourished (Tieland et al., 2017) adults. Baseline oral temperature in older adults is 97.4°F (36.3°C) versus 98.6°F (37°C) in younger adults (Lu et al., 2010).

B.  Parameters of disease assessment

  1. Note any change from baseline in function, mental status, behavior, appetite, or chronic illness (High, 2017).
  2. Assess fever. Determine baseline and monitor for changes 2°F to 2.4°F (1.1°C–1.3°C) above baseline (Liang, 2016). Oral temperatures above 99°F (37.2°C) or greater also indicate fever (High, 2017).
  3. Note typical and atypical symptoms of pneumococcal pneumonia (Liang, 2016; Mandell et al., 2007), tuberculosis (Kuchel, 2017), influenza (Talbot, 2017), acute myocardial infarction (Gray-Vickrey, 2010), UTI (Rowe & Juthani-Mehta, 2017), peritonitis (Dumic et al., 2019; Scannapieco & Cantos, 2016), and GERD (Hall, 2017).


A.  The older adult will experience successful aging through appropriate lifestyle practices and healthcare.

B.  Healthcare provider will

  1. Identify normative changes in aging and differentiate these from pathological processes.
  2. Develop interventions to correct for adverse effects associated with aging.

C.  Institution will

  1. Develop programs to promote successful aging.

D.  Provide staff education on age-related changes in health.


A.  Continue to reassess effectiveness of interventions.

B.  Incorporate continuous quality-improvement criteria into existing programs.


AHRQ         Agency for Healthcare Research and Quality

BMI             Body mass index

BP               Blood pressure

BPH            Benign prostatic hyperplasia

CDC            Centers for Disease Control and Prevention

EKG            Electrocardiogram

GERD         Gastroesophageal reflux disease

GFR            Glomerular filtration rate

JNC             Joint National Committee

MDRD        Modification of diet in renal disease

NSAID        Nonsteroidal anti-inflammatory drug

OTC            Over the counter

ROM           Range of motion

USDA         U.S. Department of Agriculture

USDHHS    U.S. Department of Health and Human Services

UTI              Urinary tract infection


Updated: November 2020

Boltz PhD, RN, GNP-BC, FGSA, FAAN, M., Capezuti PhD, RN, FAAN, E., Zwicker DrNP, APRN, BC, D., & Fulmer PhD, RN, FAAN, T. T. (2020). Evidence-Based Geriatric Nursing Protocols for Best Practice (6th ed.). Springer Publishing. Retrieved November 4, 2020, from

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