385

Pharmacological Issues in the Elderly

Hearing Impairment
See HEARING IMPAIRMENT (p. 317)

Pharmacological Issues in the Elderly
PRINCIPLES OF DRUG USE IN THE ELDERLY

PRINCIPLES OF PHARMACOLOGY elderly are at
increased risk of adverse drug reactions because of
altered physiology of aging, multiple co existing
illnesses, reduced homeostatic reserve, polypharmacy,
and medical error. Of the 4 key components of phar
macokinetics (absorption, distribution, metabolism,
excretion), only the last 3 are meaningfully affected by
age. Pharmacokinetic changes are related to decreased
renal (most important) and hepatic function (phase I
reactions #, phase II reactions unaffected), decreased
lean body mass (" fat), decreased total body water, and
increased total body fat
COMPLICATIONS falls, delirium, incontinence,
renal impairment, heart failure, gastrointestinal
hemorrhage, hypoglycemia, drug drug interactions
PRESCRIBING PRINCIPLES initiate most medica
tions at half usual starting dose, increase dose
slowly. Carry out regular medication reviews and
stop any unnecessary medications. Avoid medica
tions with known significant side effects in the
elderly. Avoid treating adverse drug reactions

with further drugs
UNDER PRESCRIBING IN THE ELDERLY

REASONS FOR UNDER PRESCRIBING under
recognitionof medication benefit in older patients,
affordability, and dose availability (i.e. requiring a
dose of medication that is smaller than supplied by
the manufacturer, resulting in more complicated dos
ing strategies such as once every other day dosing)

Lancet 2007 370:9582;
BMJ 2008 336:7644
OVER PRESCRIBING IN THE ELDERLY

POLYPHARMACY AND DRUG INTERACTIONS
57% of elderly use >5 drugs per week, 19% use
>10 drugs per week; 1 in 25 are at risk for major
drug drug interaction, nearly half involve use of
anticoagulants or antiplatelet agents
BEERS LIST list of 33 drugs that should
always be avoided (e.g. meperidine, barbitu
rates, chlorpropamide), drugs that are rarely
appropriate (e.g. diazepam, cyclobenzaprine),
and drugs with some indications but are
often misused (e.g. indomethacin, amitriptyline,
oxybutynin)
SUPPLEMENTS 49% of elderly use herbal or diet
ary supplements and are at increased risk of herb
drug interaction (e.g. ginkgo biloba and warfarin
resulting in increased bleeding risk)

AVOID TREATING ADVERSE DRUG REACTIONS
WITH FURTHER DRUGS medications are often
inappropriately prescribed to symptomatically
treat side effect of another medication. For
example, metoclopramide ! extrapyramidal
effects ! levodopa. Metoclopramide users are
>3 times more likely to be prescribed levodopa
compared to non users, a treatment generally
reserved for management of idiopathic Parkin
son’s disease

COMMON ADVERSE DRUG REACTIONS AND DRUG DRUG INTERACTIONS

CHARACTERISTIC SIDE EFFECTS OF DRUGS FREQUENTLY USED IN THE ELDERLY
Drugs
Adverse effects
a1 blockers (doxazosin)
Falls, orthostatic hypotension, dry mouth
Anticholinergics
Delirium, urinary retention, constipation, dry mouth, blurred vision,
(diphenhydramine)
postural hypotension
Benzodiazepines (lorazepam)
Falls, confusion
NSAIDs (indomethacin)
Gastrointestinal irritation and hemorrhage, renal impairment,
hypertension, heart failure
Sulfonylureas (chlorpropamide) Hypoglycemia
Tricyclic antidepressants
Falls, orthostatic hypotension, sedation, delirium, arrhythmias

(amitriptyline)


386
COMMON ADVERSE DRUG REACTIONS AND
DRUG DRUG INTERACTIONS (CONT’D)

WARFARIN INTERACTIONS many medications
implicated in increasing bleeding risk (" INR) with
warfarin. Most severe interactions described with
trimethoprim sulfamethoxazole,
erythromycin,
amiodarone, propafenone, ketoconazole, flucona
zole, itraconazole, metronidazole. Antibiotics, aceta
minophen, steroids, and ginkgo biloba may also
increase bleeding risk

Pharmacological Issues in the Elderly

COMMON ADVERSE DRUG REACTIONS AND
DRUG DRUG INTERACTIONS (CONT’D)

GRAPEFRUIT JUICE INTERACTIONS grapefruit
interferes with drugs that are metabolized by CYP3A4,
including statins (simvastatin/lovastatin > atorvastatin),
calcium channel blockers, and benzodiazepines
HEART FAILURE PRECIPITANTS AND EXACER
BANTS NSAIDs (>2 times risk for admission for
HF, correlating with dose of drug), thiazolidinediones,
sodium polystyrene sulfonate



Notes

Notes

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388

Notes

Notes


14
PALLIATIVE CARE
Section Editors:
Dr. Sriram Yennurajalingam and Dr. Eduardo Bruera
Palliative Care-Specific Issues
INTRODUCTION

DEFINITION according to the World Health Orga
nization, palliative care is ‘an approach that improves
the quality of life of patients and their families facing
the problem associated with life threatening illness,
through the prevention and relief of suffering by
means of early identification and impeccable assess
ment and treatment of pain and other problems,

physical, psychosocial and spiritual. . . Palliative care
is applicable early in the course of illness, in conjunc
tion with other therapies that are intended to prolong
life, such as chemotherapy or radiation therapy, and
includes those investigations needed to better under
stand and manage distressing clinical complications.’’
RELIEF OF SUFFERING suffering is defined as ‘the
state of severe distress associated with events that
threaten the intactness of the person.’’ Living with
advanced disease, particularly at the end of life,
inevitably involves variable degrees of physical, psy
chosocial, and existential suffering
REFERRAL TO PALLIATIVE CARE while palliative
care is commonly associated with end of life care, it is

INTRODUCTION (CONT’D)

most effective when incorporated early in the disease
trajectory of life limiting illnesses. Timely incorpora
tion of palliative care principles can help to optimize
symptom management, improve psychosocial inter
ventions, enhance coordination of care, and facilitate
patients’ transition from active treatment to end of
life care. Thus, patients living with incurable life
threatening conditions, such as advanced cancer,
COPD, end stage cardiac failure, stage V chronic
kidney disease, progressive liver failure, and AIDS
would benefit from palliative care involvement
SYMPTOM COMPLEX AND ASSESSMENT


SYMPTOM COMPLEX patients with advanced dis
ease typically experience multiple symptoms at the
same time. In addition to underlying disease and
associated symptom burden, expression of symptom
is modulated by patients’ psychosocial and existential
distress, cultural background, personality, past
experiences, and comorbidities

SYMPTOM PREVALENCE IN TERMINALLY ILL PATIENTS
Symptom
Cancer
AIDS
Heart Failure
Pain
35 96%
63 80%
41 77%
Depression
3 77%
10 82%
9 36%
Delirium
6 93%
30 65%
30 65%
Fatigue
32 90%
54 85%
69 82%
Dyspnea

10 70%
11 62%
60 88%
Anorexia
30 92%
57%
21 41%

SYMPTOM COMPLEX AND ASSESSMENT (CONT’D)

COMPREHENSIVE PALLIATIVE CARE ASSESS
MENT given the intricate nature of interaction
between physical, psychosocial, and existential, it is
important to perform regular screening to accurately
assess and manage the symptoms
 SYMPTOM BATTERY Edmonton Symptom Assessment
Scale (ESAS, Likert scale of 1 10 for 10 symptoms

COPD
34 77%
37 71%
18 32%
68 80%
90 95%
35 67%

CKD
47 50%
5 61%
18 33%

73 87%
11 62%
25 64%
JPSM 2006 31:1

SYMPTOM COMPLEX AND ASSESSMENT (CONT’D)




including pain, fatigue, nausea, depression, anxi
ety, drowsiness, appetite, well being, shortness of
breath, and sleep), global assessment scale
PAIN Edmonton Pain Classification System
DELIRIUM Mini Mental State Examination, Mem
orial Delirium Assessment Scale

D. Hui, Approach to Internal Medicine, DOI 10.1007/978 1 4419 6505 9 14,
ể Springer ScienceỵBusiness Media, LLC 2006, 2007, 2011

389