Geriatrics and Aging

Young-old

Individuals aged 65 to 74 years.

Middle-old

Individuals aged 75 to 84 years.

Old-old

Individuals older than 85 years.

Average lifespan

Women: 85 years; Men: 83 years.

Senescence

Progressive loss of cell replication ability.

Physiological reserve

Decreases ability to repair and adapt.

Multicausality

Senescent changes from internal and environmental factors.

Immunosenescence

Decline in immune response with aging.

Cytokine secretion

Decreased levels, especially tumor necrosis factor.

Respiratory response

Decreased reaction to hypoxia and hypercapnia.

Tachypnea

Rapid breathing, often absent in older adults.

Dyspnea

Shortness of breath, may be less noticeable.

Renal function

85-year-olds have 50% efficiency of 30-year-olds.

GI motility

Slowed and less coordinated due to nerve decline.

Presbyesophagus

Weakened lower esophageal sphincter causing GERD.

Intrinsic factor

Needed for Vitamin B12 absorption, decreases with age.

Clostridium Difficile

Increased infection risk due to gut changes.

Insulin resistance

Decreased insulin production leads to type 2 diabetes.

Genitourinary Syndrome

Changes due to decreased estrogen in women.

Benign prostatic hypertrophy

Enlargement of the prostate gland in men.

Skin changes

Drier, thinner, less elastic skin in older adults.

Muscle changes

Muscle replaced by fat and connective tissue.

Neurotransmitter decrease

May cause sleep and memory issues.

Chronic Pain

Persistent pain condition common in older adults.

Dementias

Includes Alzheimer's, vascular, Lewy body, and frontotemporal.

Geriatric syndromes

Includes urinary incontinence, falls, and delirium.

Frailty

Constellation of symptoms indicating increased vulnerability.

Beers criteria

Guidelines to avoid inappropriate medications in elderly.

Altered medication effectiveness

Changes in absorption and metabolism in older adults.

Greater body fat

Lipid-soluble drugs remain longer in the body.

Physiological reserve decreases with aging

The ability to repair damage and adapt to physiological stressors decreases.

Multicausality

Both internal processes and influences from the environment cause senescent cell changes

inflammation

Process of inflammation declines

external signs and symptoms

Decreased external signs and symptoms

white blood cell (WBC) numbers

With infection, white blood cell (WBC) numbers do not rise to the same level as in younger adults

Fever

 commonly absent

Immunizations

may be less effective in the older adult

Behavioral or mental status changes

should increase suspicion of a covert infection in the older adult.

hypoxia and hypercapnia.

Decreased response

Older adults with serious respiratory conditions

may not exhibit the “early warning signs” of tachypnea and dyspnea. This can lead to delayed diagnosis.

Decreased ability to respond to hypoxia

Switch to anaerobic respiration earlier in illness to make energy. They develop acid-base imbalances earlier in illness.

Less effective ventilation

• Decreased elasticity of the thoracic rib cage and lung tissue

• Diminished respiratory muscle strength

Less effective gas exchange:

• Alveoli lose surface area

  • Diameter of the bronchioles and smaller airways

Older adults are more dependent on

•  the abdominal muscles for ventilation, less use of the diaphragm muscle.

  • *Weaker cough reflex: this leads to pooling of secretions in the lungs and a greater risk for infections.

Renal decline causes

• • Nephrons (decreases are normal part of aging but not to point of renal insufficiency/failure)

• • Activity, number, and length of proximal tubules

• • Blood flow to the kidney due to atrophy of the arterial blood vessels (esp. in the renal cortex)

• • Response to ADH

• • Ability to correct acid-base imbalances

• ◦ Leads to decreased ability to respond to fluid overload and to concentrate urine.

Gastrointestinal

• GI motility slows, less coordinated

  • ◦ Due to autonomic nerve decline in the GI tract; this is most severe in the distal portions (rectal & sigmoid)

  • ◦ Leads to decreased peristalsis and constipation

  • ◦ Denervation of intestines & colon-contribute to diverticulosis

Eating & Appetite Changes

• ◦ Senses (taste & smell) decline

• ◦ Swallowing impairments occur due to muscle weakness, less coordinated

• ◦ Presbyesophagus-weaker lower esophageal sphincter, leads to GERD (acid reflux)

Gastrointestinal

• Nutrient & electrolytes deficits

• Atrophy of gastric lining leads to less intrinsic factor (this is needed for Vitamin B12 absorption). This condition is called __________________.

  • Decreased HCL & flattened villi---deficiencies in calcium & iron.

Changes in gut microbiome

• • Lead to lactose intolerance

• • Increased risk of Clostridium Difficile infection

Insulin and Thyroxine Undergo Changes

• ◦ Pancreatic beta islet activity decrease=decreased insulin production, other changes (more body fat, less physical activity)

  • ◦ Contribute to insulin resistance and type 2 diabetes

• ◦ The thyroid gland shrinks with age; less able to convert T4 to T3

  • ◦ Increased risk of hypothyroidism and obesity (burn less calories)

Gynecological and urological changes that occur due to decline in estrogen levels

• ▪ Thinner, drier genital tissues and less muscle weakness (sexual dysfunction)

• ▪ Weaker pelvic musculature, bladder, and urethra (bladder incontinence)

• ▪ Changes in local vaginal flora (increased risk of UTIs)

Male Genitourinary

• • Enlargement of the prostate gland (benign prostatic hypertrophy)

• • Testicular changes

• • Decreased testosterone; fertility-decreased sperm, more abnormal sperm

Integumentary system 

• Skin is drier, thinner, less elastic, and more fragile.

• Older adults are less able to thermoregulate.

• Develop more skin lesions (discolorations, purpura, ecchymosis, cancerous changes)

• Increased risk of skin breakdown

• Causes

  • Environmental free radicals and sun exposure

  • Several physical changes

Musculoskeletal system 

• Changes in muscle mass, strength, and oxygen uptake

• Muscle is replaced by fat and connective tissue

• Age-related loss of bone, particularly in the trabecular (nonsolid) bones of the body, vertebrae, hip, and wrist.

• Estrogen protects women until menopause

Nervous system 

• Neurotransmitters decrease with increased age.

  • May be cause of sleep pattern change and mild memory loss.

    • Plasticity remains intact (with stimulation)

Peripheral nervous system changes.

• ◦ Loss of myelin

• ◦ Nutritional deficiencies can affect nervous system- Vitamin B12 (pernicious anemia), leads to neuropathy

• ◦ Pain threshold-may take more stimulus for them to detect pain

• ◦ Less able to tolerate unrelieved pain (once detected)

• ◦ May experience greater visceral pain intensity

• ◦ Vison and hearing decline

Common age related diseases

• Chronic Pain

• Chronic Renal Failure

• Dementias

  • • Alzheimer’s Disease

  • • Vascular Dementia

  • • Lewy Body Dementia

  • • Frontotemporal Dementia (Pick’s disease)

• Type 2 Diabetes

• Hypertension

• Heart Failure

• Infections

  • • Remember “wind, water, wounds” when an older adult has a sudden change in mental status. Infections of the respiratory, urinary, or integumentary systems may be the cause.

Geriatric syndromes

• Urinary incontinence, falls, pressure wounds, delirium, and functional decline are some common examples of geriatric syndromes.

• Frailty in an older adult is described as  constellation of symptoms.

  • • These include weakness, weight loss, decreased balance and physical activity, slowness, social withdrawal, cognitive impairments, and fatigue.

  • • Increased vulnerability to stressors--physiological or psychosocial threat.

  • • For example, a frail older adult with coronary artery disease could not endure angioplasty or coronary bypass surgery; therefore, long-acting nitrate medications are used instead.

Geriatric considerations for pharmacology: Altered medication and effectiveness 

• Changes in the kidney, liver, intestine, muscle, and subcutaneous fat of older adults affect how medications are absorbed and distributed in the body.

• Absorption, distribution, metabolism, and excretion may all be affected.

• Decreased muscle mass----intramuscular injections are absorbed faster initially.

  • *Decreased peripheral blood flow may slow down the distribution and subsequent absorption of the medicine.

• Greater body fat----lipid soluble medications remain in the body longer.

• Less body water---water soluble medication is metabolized more quickly.

• Less protein stores---less medication is bound to albumin, more drug free in the bloodstream leads to greater concentrations (greater risk of toxicity).

Altered medication effectiveness

• Liver-less able to metabolize medications; diminished ability to detoxify substances.

• Kidneys-less effective in excreting drug metabolites

• Diminished liver & kidney function increase risk of accidental overdose.

• Diminished immune function makes antibiotic therapy more difficult, they usually need higher doses of antibiotics, this can be challenging in older adults (increased risk of toxicity, side effects, allergies, and adverse reactions).

• Beers criteria- guidelines to help avoid use of inappropriate medications in the elderly.