How and Why Older People Get Sick

Epidemiology of Aging

In the UK, the population of individuals over 85 years has seen substantial growth:

  • 1981: 600,000
  • 2011: 1.5 million
  • 2026 (projected): 2.4 million

The prevalence of chronic illness or disability that restricts daily activities also increases with age.

  • 50-64 years: 25%
  • >85 years:
    • Men: 66%
    • Women: 75%

Life expectancy at birth in the UK:

  • Males: 79.5 years
  • Females: 83.1 years

In 2021, 18.6% of the UK population was aged >65 (compared to 16.4% in 2011), including 500,000 people aged >90.

Physiological Changes and Clinical Consequences in Aging

The aging process leads to several changes in various body systems, which can have significant clinical consequences:

Central Nervous System (CNS)

  • Changes:
    • Neuronal loss
    • Cochlear degeneration
    • Lens rigidity
    • Lens opacification
    • Anterior horn cell loss
    • Dorsal column loss
    • Slowed reaction time
  • Clinical Consequences:
    • Increased risk of delirium
    • Hearing loss
    • Presbyopia
    • Cataract
    • Muscle wasting
    • Reduced proprioception
    • Increased risk of falls

Respiratory System

  • Changes:
    • Reduced lung elasticity
    • Increased chest wall rigidity
    • Increased V/Q mismatch
    • Reduced cough/ciliary action
  • Clinical Consequences:
    • Reduced vital capacity/peak flow
    • Increased residual volume
    • Reduced oxygen saturation
    • Increased risk of infection

Cardiovascular System

  • Changes:
    • Reduced maximum heart rate
    • Dilatation of aorta
    • Reduced elasticity of vessels
    • Reduced number of pacing myocytes in the sinoatrial node
  • Clinical Consequences:
    • Reduced exercise tolerance
    • Widened pulse pressure
    • Increased risk of postural hypotension

Gastrointestinal System

  • Changes:
    • Reduced motility
  • Clinical Consequences:
    • Constipation

Renal System

  • Changes:
    • Loss of nephrons
    • Reduced glomerular filtration rate
    • Reduced tubular function
  • Clinical Consequences:
    • Impaired fluid balance
    • Increased risk of dehydration/overload
    • Impaired drug excretion/metabolism

Endocrine System

  • Changes:
    • Deterioration in pancreatic beta-cell function
  • Clinical Consequences:
    • Increased risk of impaired glucose tolerance

Bones

  • Changes:
    • Reduced bone mineral density
  • Clinical Consequences:
    • Increased risk of osteoporosis and fragility fractures

Frailty

Frailty is defined as the loss of physiological reserve, which leads to increased vulnerability to poor health outcomes. It is important to note that frailty is not the same as disability or comorbidity.

  • Disability = Established loss of function
  • Co-morbidity = Number of diagnoses

Prevalence of frailty:

  • 60-69 years: 6.5%
  • >90 years: 65%

Clinical Issues in Older Patients

  • Multiple comorbidities: Older patients often have several coexisting diseases.
  • Nonspecific symptoms: Symptoms may be vague or not directly related to a specific disease.
  • Atypical/late presentation: Diseases may manifest differently compared to younger patients.
  • Lack of physiological reserve: Illnesses can develop quickly, recovery takes longer, and complications are more likely.
  • Altered drug metabolism: Doses may need adjustment due to changes in metabolism, increasing the risk of side effects and polypharmacy.

Common Presentations of Frailty

  • Postural hypotension
  • Falls
  • Neck of femur fracture
  • Delirium
  • Poor nutrition

Case Study: Doreen

  • 76-year-old woman
  • PMHx (Past Medical History):
    • Osteoarthritis
    • Chronic Kidney Disease
    • Hypertension
    • Postural hypotension
  • SHx (Social History):
    • Lives with her husband, who has dementia
    • Has three daughters: Maggie (nearby), Elsa (Birmingham), and Jane (New Zealand)
    • Handles all cooking and shopping, mobilizes independently but with limited walking ability
    • Maggie assists with cleaning once a week
    • No formal carers
    • Smokes 20 cigarettes per day

Clinical Frailty Scale: Rockwood Score

The Clinical Frailty Scale is used to assess the overall fitness and frailty level of an individual.

  • 1 Very Fit
  • 2 Well
  • 3 Managing Well
  • 4 Vulnerable
  • 5 Mildly Frail
  • 6 Moderately Frail
  • 7 Severely Frail
  • 8 Very Severely Frail
  • 9 Terminally Ill

The degree of frailty corresponds to the degree of dementia.

Case Progression

  • Doreen’s husband develops a cough and fever, with increased confusion.
  • Doreen tries to manage independently, leading to a fall due to postural hypotension and a broken hip.
  • Doreen is then admitted to hospital.

Postural Hypotension

A fall in systolic blood pressure of ≥20mmHg\ge 20mmHg and/or a fall in diastolic blood pressure of ≥10mmHg\ge 10mmHg from lying to standing.

Causes:

  • Aging
  • Hypovolaemia
  • Medications (diuretics, anti-hypertensives)
  • Autonomic dysfunction (e.g., diabetes mellitus, Parkinson’s Disease)

Management:

  • Stop medications that can interfere
  • Lifestyle factors:
    • Adequate fluid intake
    • Standing slowly
    • Compression stockings
  • Fludrocortisone (promotes Na+Na^+ and water retention)

Polypharmacy

Commonly defined as taking 5 or more medications simultaneously.

  • Nearly 50% of older adults take one or more medications that are not medically necessary.
  • Polypharmacy is strongly associated with negative clinical consequences.

Falls

Falls can be a presentation of multiple underlying pathologies:

  • Acute illness (e.g., infection, stroke)
  • Blackouts
  • Gait and balance issues

Statistics:

  • >65-year-olds: 30% fall each year
  • >80-year-olds: 40% fall each year
  • 10-15% of falls result in serious injury

Risk factors include:

  • Age
  • Loss of muscle mass
  • Visual impairment
  • Cognitive impairment
  • Gait or balance abnormality
  • Postural hypotension
  • Previous falls
  • Impaired activities of daily living
  • Alcohol/medications
  • Arthritis/pain
  • Peripheral neuropathy
  • Parkinson’s disease

Prevention:

  • Multi-disciplinary approach
  • Falls clinic
  • Rationalize medications
  • Visual aids
  • Walking aids
  • Appropriate footwear
  • Review home circumstances

Fractured Neck of Femur

Fractured neck of femur is common and associated with high mortality.

  • 10% die within 1 month, and a third die within one year.
  • Can occur with minor trauma in the elderly due to decreased bone density.

Osteoporosis:

  • Low bone mass and micro-architectural deterioration of bone tissue leading to bone fragility and increased fracture risk.
  • Fragility fractures result from falls from standing height or less.
  • Common sites include the spine, wrist, and hip.

Presentation:

  • Usually after a fall
  • Painful, shortened, and externally rotated leg

Investigations:

  • X-ray
  • Sometimes CT scan

Management:

  • Analgesia
  • Surgery
    • Total hip replacement/hemiarthroplasty
    • Dynamic hip screw
  • Excellent, holistic postoperative care is vital.
  • NICE (National Institute for Health and Care Excellence) advise surgery on the day of or day after admission.

Doreen's Post-operative Complications

  • Right total hip replacement.
  • Develops confusion and agitation in hospital.
  • Slow progress with physiotherapy.
  • Develops a small pressure sore.
  • Maggie notices Doreen looks more gaunt.
  • Eric is placed in 24-hour care.

Dementia, Delirium, and Depression

  • All present similarly in the elderly and commonly get mixed up
  • Dementia = syndrome associated with an ongoing decline in brain functioning (NHS definition)
  • Delirium = acute confusional state with reversible* cognitive dysfunction
  • Depression = common mental health problem causing persistent low mood and loss of interest in activities you would normally enjoy

Delirium

Very common in the elderly (up to 30% of older inpatients).

Fluctuating abnormalities of:

  • Thought
  • Perception
  • Levels of awareness

Usually hypoactive or hyperactive.

More common with a background of dementia.

Associated with high rates of mortality (25% to 33%).

Precipitating factors:

  • Pain
  • Infection
  • Nutrition
  • Constipation
  • Hydration
  • Medication
  • Environment

Predisposing factors:

  • Old age
  • Dementia
  • Frailty
  • Sensory impairment
  • Polypharmacy
  • Renal impairment

Assessment:

  • History (may need collateral history)
  • Comprehensive examination (obs, CVS, resp, abdo, GU, neuro, skin)
  • Assessment tools (AMTS, MOCA, 4AT)
  • Other investigations
    • CXR, ECG
    • Urine culture (do not do urine dip in >65)
    • CT head
    • ‘Confusion bloods’ (Full blood count, Urea and electrolytes, Liver function tests, Clotting tests, Thyroid tests, Calcium, B12 and folate (ferritin), Glucose)

Management:

  • Supportive (specialist teams)
  • Medication review (avoid sedatives)
  • Identify and treat the underlying cause

Doreen's Later Life

  • Discharged to residential care.
  • Remains confused.
  • Maggie feels she is “not as sharp as she used to be”.
  • Mobilises with a Zimmer frame.
  • Needs help with washing and dressing.
  • Starts to eat less and refuses most of her meals.

Nutrition

The elderly are particularly at risk of under-nutrition.

  • Reduced muscle mass, increased percentage body fat.
  • Basal metabolic rate is reduced, and energy requirements are reduced.
  • Weight tends to fall over the age of 70.

Reasons for weight loss:

  • Decreased appetite
  • Difficulty preparing food
  • Loss of taste
  • Financial difficulties
  • Difficulties getting shopping
  • Poor dental health
  • Illness
  • Cognition

Clinical consequences of malnutrition:

  • Impaired immunity
  • Muscle weakness
  • Poor wound healing

Frailty and Outcomes in Acute Care

  • The Clinical Frailty Scale (CFS) grade is related to length of stay, readmission rate, in-patient mortality, care intentions, service referrals, and post-discharge support.

Preventable Frailty?

  • "Healthy ageing" reduces the risk of developing frailty.
    • Good nutrition
    • Staying physically active
    • Remaining engaged in the local community/avoiding loneliness

Adapting Care

Moving towards holistic patient-centered care based on the individual patient

Summary

  • We are an aging population.
  • More elderly people now are living with significant comorbidity and frailty.
  • There are several challenges when dealing with elderly patients:
    • They present atypically/non-specifically, have multiple comorbidities, and have reduced physiological reserve.
  • Geriatricians need to take a holistic approach when caring for elderly patients
  • Multiple comorbidities, biopsychosocial aspects to disease.
  • We have highlighted some examples of common conditions affecting elderly patients. There are many, many more…