PHYSICAL CHANGES OF AGING

Physiologic aging may be the most significant factor challenging quality of life. It is not known exactly how and why people change as they get older, and there are many theories about it. Some changes always occur with aging, but they occur at different rates and to different extents. There is no way to predict exactly how any given individual will age.

Musculoskeletal Changes

Bones lose calcium and other minerals, and bone mass or density decline occurs, especially in postmenopausal women. Vertebral disks lose fluid and become thinner. Vertebrae lose some mineral content, resulting in thinning, and bone spurs may form. The spinal column curves and compresses, posture may become stooped, and postural hyperkyphosis may occur.

Joints become stiffer and less flexible, and fluid may decrease. Cartilage may start to rub together and wear away. Calcifications may occur, commonly around the shoulder. Hip and knee joints also begin to lose cartilage, as well the finger joints, which may also develop bony osteophytes.

Muscle tissue may be replaced with tough, fibrous tissue, most noticeable in the hands. Muscles lose tone and are less able to contract as a result of muscle tissue and nervous system changes. Muscles may become rigid and lose tone, even with regular exercise. Lean body mass decreases partly due to atrophy of muscle tissue. The loss of muscle is associated with decreased strength, slower movement, and movement limitations. Recovery of older muscle after injury is slowed and frequently incomplete, and muscle contractions may occur in those who are unable to move on their own or who do not stretch their muscles with exercise.

Common problems that occur with musculoskeletal aging include:

• Osteoporosis, especially for older women
• Compression fractures of the vertebrae, which can result in pain and reduced mobility
• Muscle weakness, contributing to fatigue, weakness, and reduced activity tolerance
• Joint problems ranging from mild stiffness to debilitating osteoarthritis
• Increased risk of injury due to gait changes, instability, and loss of balance that can lead to falls
• Reduced reflexes, most often due to changes in muscles and tendons, rather than changes in nerves; decreased knee or ankle jerk reflexes; and positive Babinski reflex
• Involuntary movements such as muscle tremors (fasciculations) and fine movements
• Weakness or abnormal sensations (paresthesias)
• Inability to move, or lack of stretching of muscle, resulting in muscle contractures
  (Brodkey, 2022)

MANAGEMENT AND PREVENTION

Management strategies for musculoskeletal disorders include:

• Physical exercise, alone or in combination with nutritional intervention, including high-intensity resistance training, a balanced program of endurance, and strength exercises
• Nutritional supplements, including vitamin D
• Programs to prevent falls and optimize bone health

Recommendations for arthritis include:

• Weight loss
• Physical therapy
• Supervised progressive exercise
• Provision of custom or prefabricated orthotic devices

Falls are the most common cause of fractures in older people. Most older adults can benefit from targeted programs to prevent falls and optimize bone health (Minetto et al., 2020).

Integumentary Changes

Skin changes are the most visible signs of aging. Growths such as skin tags, warts, rough patches (keratoses), and other blemishes are more common. Skin cancers are common and usually located in sun-exposed areas. More than 90% of all older people have some type of skin disorder, such as xerosis, pruritus, eczematous dermatitis, and purpura. Aging skin repairs itself more slowly. Wound healing may be up to four times slower, contributing to pressure ulcers and infections. The skin’s ability to produce vitamin D declines, affecting bone health (Brodkey, 2022; Rosen, 2023).

Sebaceous glands produce less oil, resulting in dryness and itchiness. Sweat glands produce less sweat, making it hard to keep cool.

Changes in nails can impair ability to perform daily activities. Pits, ridges, lines, and changes in shape may be related to iron deficiency, kidney disease, and nutritional deficiencies (Brodkey, 2022).

MANAGEMENT AND PREVENTION

Maintaining skin integrity is essential, requiring a holistic and interdisciplinary approach, and includes:

• Performing regular skin assessments
• Maintaining mobility
• Relieving pressure
• Using safe manual handling techniques
• Providing skin care, paying attention to high-risk areas
• Encouraging good nutrition and hydration
• Inspecting feet daily
• Consulting a podiatrist if necessary

Because many older adults had chicken pox as children, they are risk for shingles and should obtain a vaccine if there are no contraindications (Fraser, 2020; Consultant 360, 2023; EHS, 2023; Brodkey, 2022).

Cardiovascular Changes

Some cardiovascular changes in the older adult are normal and inevitable, while others are influenced by modifiable factors such as lifestyle and health conditions.

As people age, heart muscle thickens and becomes stiffer, reducing the amount of blood the heart can pump, leading to decline in exercise capacity and a higher risk of heart failure.

The electrical system of the heart becomes less sensitive, increasing risk for abnormal rhythms such as atrial fibrillation, likewise increasing risk for stroke.

Large arteries stiffen and lose elasticity, causing hypertension, which can damage blood vessels and organs and increase the risk of heart attack and stroke. Walls of the smaller arteries and arterioles also become harder and thicker (arteriosclerosis). Deposits of yellowish plaque containing lipids and cholesterol (atherosclerosis) build up on the artery walls, narrowing the lumen.

Capillaries thicken and become less permeable, slowing down exchange of oxygen and nutrients to the tissues, which can affect wound healing and the function of organs such as the skin and muscle.

Baroreceptors become less responsive, causing orthostatic hypotension, increasing risk for falls.

Cardiac aging is associated with left ventricle hypertrophy, fibrosis, and diastolic dysfunction, resulting in reduced cardiac output and risk of heart failure.

Since arteries and arterioles become less elastic, blood pressure cannot adjust quickly, putting people at risk for dizziness or fainting (NIH, 2022a).

MANAGEMENT AND PREVENTION

Management and prevention of cardiovascular issues in the older adult include patient education regarding modifying controllable risk factors such as diabetes, hypertension, overweight, diet, exercise, smoking, and alcohol intake.

Hypertension management requires lifestyle changes and pharmaceutical therapy, education on stress management, and encouragement of some form of relaxation technique (Egan, 2023).

Atrial fibrillation is often managed with anticoagulation therapy such as warfarin (Coumadin) and antiplatelet drugs such as aspirin or clopidogrel (AHA, 2023).

Peripheral vascular disease management includes avoiding prolonged standing or sitting, and exercising on a regular basis. Pharmaceutical therapy includes antiplatelet or anticlotting agents, statins, and medications that increase blood supply. Nonpharmaceutical therapy includes extremity elevation, compression stockings, exercise, and wound care for ulcerations caused by chronic venous insufficiency. Treatment for claudication is a supervised exercise program and may include the antiplatelet agent cilostazol (Berger & Davies, 2023).

Thermoregulatory Changes

Older adults have reduced autonomic and behavioral thermoregulatory responses, attenuated sweat gland output, increased threshold for onset of sweating, decreased skin blood flow, reduced cardiac output, and impaired thermal perception, placing them at high risk for hypothermia and hyperthermia (Mauk, 2023).

MANAGEMENT AND PREVENTION

Management and prevention include avoiding environmental extremes of heat or cold. Patient education includes:

• Wearing proper clothing for environmental conditions
• Maintaining a proper temperature-controlled environment in the home
• Maintaining appropriate hydration
• Using a fan or water spray when exercising or in a hot environment
• Avoiding alcohol intake in cold environments
  (Velez, 2021)

Urinary System Changes

Kidney efficiency is impaired due to halving of the number of nephrons, halving of renal blood flow, and halving of glomerular filtration rate and maximum excretory capacity by age 75, affecting ability to excrete ammonium, sodium, potassium, or medications.

However, kidneys have a large reserve capacity, and functional ability remains relatively stable unless stressed. The kidneys can maintain normal homeostasis mechanisms and waste disposal within limits, but they are less efficient, need more time, and have minimal reserves. As a result, minimal dehydration, infection, or impaired cardiac output may lead to chronic kidney failure (Physiopedia, 2023; Mauk, 2023).

With age, the bladder decreases in size, and bladder walls develop fibrous matter, affecting overall stretchability and contractibility. Filling capacity declines, along with the ability to withhold voiding. The ability of the detrusor muscle to contract declines, causing involuntary bladder muscle contractions resulting in a sudden urge to void, frequent urination, and frequent voiding at night.

In about 50% of men with benign prostatic hyperplasia (BPH), enlargement of the prostate causes obstruction of the bladder outlet, resulting in urinary dysfunction. In response, the bladder walls become thicker and stronger to compensate. If untreated, blockage may become nearly complete or complete, causing urinary retention and possibly kidney damage.

In women, due to a declining level of estrogen during menopause, the urethra shortens and the lining becomes thinner causing a decrease in the ability of the urinary sphincter to close tightly, increasing risk for urinary incontinence (Mauk, 2023; Preminger, 2022).

Urinary incontinence (UI) is a significant health problem for older adults, both physically and psychologically. Incontinence can occur due to weak bladder or pelvic floor muscles, overactive bladder muscles, damage to nerves that control the bladder related to diabetes or Parkinson’s disease, pelvic organ prolapse, medications, delirium, sensory impairment, and environmental barriers.

Most incontinence in men is related to prostatitis, injury or damage to nerves or muscles from surgery, and benign prostatic hyperplasia (NIA, 2022).

MANAGEMENT AND PREVENTION

Management and prevention of chronic kidney disease involves lowering risk by making healthy lifestyle changes, maintaining normal blood pressure, and controlling diabetes. There is no intervention for chronic kidney disease. Once damaged, kidneys cannot be repaired. Management in the event of kidney failure requires dialysis (CDC, 2023).

Bladder and urethra dysfunction management includes placing patients presenting with symptoms of urinary tract infection on an appropriate antibiotic.

Management of urinary retention caused by benign prostatic hypertrophy (BPH) includes:

• Active surveillance by a urologist
• Medications: alpha blocker tamsulosin (Flomax) and 5-alpha reductase inhibitor finasteride (Proscar)
• Less invasive procedures, such as a prostatic urethral lift (PUL) that lifts and compresses the prostate to prevent urethral blockage; water vapor thermal therapy and transurethral microwave therapy (TUMT) that destroys prostate cells; and catheterization, intermittent or indwelling
• Invasive surgical procedures, including transurethral resection of the prostate (TURP)
  (AUA, 2020)

Management of urinary incontinence depends on the type of incontinence, severity, and underlying cause, and a combination of treatments may be used (see table).

INTERVENTIONS FOR URINARY INCONTINENCE

Type	Interventions
(Mayo Clinic, 2023a)
Lifestyle changes	Weight loss Increased physical activity Smoking cessation Alcohol avoidance Decreased caffeine intake Prevention of constipation Avoiding heavy lifting Reducing intake of acidic foods Reducing liquid consumption
Behavioral techniques	Scheduled or delayed timed urination Double voiding
Physical therapy / occupational therapy	Pelvic floor exercises (e.g., Kegel’s) Muscle-strengthening exercises Electrical stimulation Biofeedback
Medications	Anticholinergics Alpha blockers for men (Flomax, Rapaflo) Antimuscarinic (mirabegron [Myrbetriq]) Topical estrogen for women
Medical devices	Vaginal rings and urethral inserts Pessary (prosthetic device inserted into the vagina for structural purposes)
Surgery	Single sling procedures Bladder neck suspension Prolapse surgery Artificial urinary sphincter implants
Supportive interventions and devices	Absorbent pads Protective undergarments, modified clothing Intermittent catheterization Indwelling catheter Condom catheter for men Urethral plugs and penile clamps

(See also the Wild Iris Medical Education course “Incontinence.”)

Respiratory Changes

Aging of the respiratory system reduces the capacity of all pulmonary functions, which may lead to decompensation when the system is stressed.

The effects of aging in other areas of the body affect the lungs. Thinning of bone and changes in shape alter the ribcage, decreasing expansion and contraction. The diaphragm weakens, impairing inhalation and exhalation, resulting in a lower oxygen level in the body and increased carbon dioxide level.

Muscles and other tissues adjacent to the airways may lose the ability to keep airways completely open, and progressive calcification of the walls of the trachea and bronchi causes increasing rigidity, resulting in a decrease in maximum breathing capacity. Walls of the alveoli deteriorate, lose shape, and become baggy, allowing air to become trapped in the lungs, making it hard to breathe and impairing gas exchange.

The nervous system, which monitors respiratory volume and blood gas levels and regulates respiratory rate, may lose some of its function. Breathing may become more difficult and gas exchange impaired. Nerves in the airways that trigger the protective cough reflex become less sensitive. Dysphagia or impaired esophageal motility may exacerbate the tendency to aspirate (Brodkey, 2022).

MANAGEMENT AND PREVENTION

Because older people are at highest risk of developing pneumonia, both influenza and pneumococcal pneumonia vaccines are highly recommended.

Risk for COPD and emphysema can be reduced through lifestyle management including:

• Encouraging smoking cessation
• Avoiding polluted air
• Weight reduction to improve diaphragm function
  (NIH, 2022b)

Management for COPD includes:

• Inhaled medication (bronchodilators, steroids)
• Smoking cessation
• Oxygen therapy
• Pulmonary rehabilitation
  (Health in Aging, 2023)

Emphysema, a form of COPD, can be treated with the Zephyr valve, a one-way valve placed in three to five airways that reduces hyperinflation of a portion of the lung (Dransfield et al., 2020).

Endocrine Changes

Endocrine function generally declines with age as hormone receptors become less sensitive. Some hormones that decrease with aging include:

• Growth hormone and serum IGF-1
• Gonadotropin-releasing hormone
• Luteinizing hormone (LH)
• Follicle-stimulating hormone (FS)
• Melatonin
• Insulin
• Vasopressin
  (Utiger, 2023)

Thyroid and adrenal function do not significantly change, but normal aging results in subtle changes in adrenal secretion of both ACTH and cortisol (NIH, 2022c).

With the decline in sex hormones, menopause in women may cause vaginal dryness, irritation/itching, inadequate lubrication, and dyspareunia (painful intercourse). Andropause in men may include erectile dysfunction (ED), and some may develop testosterone deficiency that can severely reduce libido.

MANAGEMENT AND PREVENTION

Management for the symptoms of menopause include vaginal moisturizers and lubricants, vaginal estrogens, and oral or transdermal hormone therapy. Gabapentin may be prescribed for those who cannot use estrogen.

Management and prevention for erectile dysfunction includes:

• Healthy lifestyle choice
• Managing existing chronic health conditions
• Screening for depression or other psychological cause
• Moderate to vigorous aerobic exercise
• Oral, rectal, or injected drugs (Viagra, alprostadil self-injection or suppository)
• Testosterone replacement
• Penis pumps
• Penile implants

Testosterone treatment may be considered in men who want to improve their sexual function. Risks include stimulating the growth of metastatic prostate cancer, increased risk of heart attack and stroke, and blood clot formation in the veins (Mayo Clinic, 2023b).

Management of hyperparathyroidism includes parathyroidectomy (Rizk et al., 2023).

Management of excess adrenal secretion includes exercise, adequate sleep, a healthy diet, and mind-body practices such as yoga (Cleveland Clinic, 2020a).

Patients with hyperthyroidism may be started on antithyroid medications such as methimazole (Tapazole) or beta blockers. For those with hypothyroidism, management includes thyroid replacement medication such as levothyroxine (Cleveland Clinic, 2020a).

For patients with diabetes, management includes a medical nutrition evaluation and exercise counseling. Metformin and insulin are considered first-line therapy (Munshi, 2023).

Gastrointestinal Changes

Aging has less effect on digestive system function than on other organ systems. Older adults are more likely to develop diverticulosis and to have digestive tract disorders, such as constipation, as a side effect of taking certain medications.

Taste and smell gradually begin to diminish, less saliva is produced, and gums recede slightly. Tooth enamel tends to wear away, increasing susceptibility to decay.

Contractions of the esophagus and tensions in the upper esophageal sphincter decrease, but the movement of food is not impaired. Some older adults, however, can be affected by diseases or disorders that interfere with esophageal contractions.

The stomach lining’s capacity to resist damage decreases, which in turn may increase risk of peptic ulcer disease, especially in those who use aspirin or NSAIDs. Conditions such as atrophic gastritis become more common, resulting in problems such as vitamin B₁₂ deficiency or small intestinal bacterial overgrowth.

Minor changes occur in the structure of the small intestine, but excessive growth of certain bacteria can lead to pain, bloating, and weight loss, as well as decreased absorption of nutrients such as iron and calcium.

The pancreas decreases in weight, and some tissue is replaced by fibrosis. These changes, however, do not decrease the pancreas’s ability to produce digestive enzymes and sodium bicarbonate.

As the liver and gallbladder age, structural and microscopic changes occur. The ability of the liver to metabolize many substances decreases, and some drugs are not inactivated as quickly.

The large intestine does not undergo much change with aging, but the rectum does enlarge somewhat, and constipation becomes more common. Bowel movements may become infrequent or painful, and stools may be hard and dry. Constipation can be triggered as a side effect of medication or a symptom of another disorder. Other changes include a slight slowing in the movement of contents, a modest decrease in rectal contractions, and pelvic floor weakness in women, which can contribute to fecal incontinence (Bartel, 2022).

MANAGEMENT AND PREVENTION

Basic management and prevention involve regular physical exercise, a healthy diet that includes foods high in fiber, reduced salt consumption, adequate fluid intake, and avoiding caffeinated and alcoholic beverages.

Interventions for constipation that increase the sensation of the need to defecate include a high-fiber diet, maintaining adequate fluid intake, physical activity, regular toilet routine, osmotic laxatives, stool softeners, lubricants or stimulant laxatives, suppositories, or small enemas (Cleveland Clinic, 2020c; GI Society, 2022).

Sensory Changes

Sensory changes in later life affect how people perceive and experience the world and can have an enormous impact on independence, safety, and quality of life. All five senses—vision, hearing, taste, smell, and touch—diminish in acuity with age. Aging raises the threshold of the amount of stimulation necessary to become aware of a sensation (NIH, 2022d).

Vision is affected by changes in all of the eye structures. The cornea become less sensitive, making eye injuries less noticeable. Pupils react more slowly to darkness and bright light. The lens becomes yellowed, less elastic, and slightly cloudy. Eye muscles become less able to fully rotate the eye.

Eyes become less able to tolerate glare, and problems with glare, brightness, and darkness may lead to impaired night vision and reduced color discrimination. Visual acuity gradually declines, causing difficulty focusing on close-up objects (presbyopia). Common eye disorders include cataracts, glaucoma, age-related macular degeneration, and retinopathies (NIH, 2022d).

Age-related hearing loss (presbycusis) affects both ears, particularly the ability to hear high-frequency sounds. There may be problems in differentiating between certain sounds or with hearing a conversation in the presence of background noise (NIH, 2022d).

MANAGEMENT AND PREVENTION

Vision loss management and prevention include reminding patients to follow the recommendation of the American Academy of Ophthalmology for a comprehensive vision exam every year or every other year, and to ensure the patient has the proper eyeglass or contact lens prescription and to recommend a diet rich in vitamins C and E, zinc, lutein, zeaxanthin, and omega-3 fatty acids (Boyd, 2023; Gregori, 2023).

Hearing loss management includes examination of the external auditory canal and removal of an accumulation of cerumen. If patient uses hearing aids, they should be removed and examined to determine whether the ear mold or plastic tubing is plugged with wax or the battery is dead (NIH, 2023). Management of conductive hearing loss may include removing wax, draining fluid, or surgery involving the eardrum or bones in the ear. Sensorineural hearing loss cannot be treated, but hearing aids or cochlear implants may be used.

Prevention measures include management of hypertension and diabetes; smoking cessation; limiting alcohol use; avoiding ototoxic drugs whenever possible; eating foods high in vitamins A, C, E, and especially B₁₂; and wearing hearing protection in noisy environments (NIH, 2022d; Victory, 2022).

Nutritional Changes

Older adults generally require fewer calories because decreased muscle mass contributes to a decline in metabolism and mobility. Gastrointestinal function becomes less efficient, making it harder to absorb nutrients, and this can lead to deficiencies in certain vitamins and minerals. The body tends to store more fat with aging, which contributes to the risk of overweight and obesity and further risk for diabetes and cardiovascular disease.

Malnutrition in the older adult can lead to problems such as:

• An increased risk of death and/or hospitalization
• A weakened immune system, increasing risk of infections
• Decreased bone mass and muscle weakness, increasing risk of falls and fractures
• Poor wound healing
  (Swiner, 2023)

During menopause women require more calcium and vitamin D to maintain strong bones. In men who are experiencing reduced testosterone, additional protein is required to maintain muscle mass (Cochran, 2023).

MANAGEMENT AND PREVENTION

Interventions for patients who are malnourished are directed at the underlying cause (e.g., treatment for depression) as well as dietary modification. Nutritional restrictions are lifted for patients with diabetes who may do well with a regular diet and adequate monitoring. High-calorie foods are recommended. Oral nutritional supplementation for patients who do not regain weight are also recommended, with adjustments in meal preparation and diet.

Advice regarding weight loss of the overweight older person is tailored to the individual, assessing the impact of excess weight on quality of life, and includes the need for regular exercise. It is not recommended that people over the age of 80 who are slightly obese be placed on calorie-restricted diets. The best option is to eat at least three meals a day that provide 30 grams of protein each and to engage in two or three weekly sessions of resistance training that taxes all the large muscle groups in order to preserve muscle mass (Ritchie & Yukawa, 2023).