Download Drug Therapy in Geriatric Patients

Drug Therapy in Geriatric
Patients
NURS 310 Winter 2016
Drug Therapy in Geriatric Patients : Learning objectives
1.
1. Stages of adulthood; patterns of health and illness
2. Demographics of the aging population:
3. Demographics of prescription and over-the-counter drug use in people
over the age of 50 is disproportionately high
a.Why does polypharmacy occur?
b.Why is it a problem?
c. What can be done about it?
4. Physiologic changes associated with aging are coupled with
pathologic changes in older adults
a.Impact of physiologic changes on pharmacokinetics
i. Absorption, distribution, metabolism, elimination
ii. Use the Cockroft-Gault Equation to calculate an age and genderadjusted creatinine clearance
b.Impact of physiologic changes on pharmacodynamics
Drug Therapy in Geriatric Patients : Learning objectives
5. Older adult patients experience more adverse drug reactions
and drug-drug interactions than younger patients.
6. How can the nurse decrease the incidence of adverse drug reactions
and drug-drug interactions in the elderly?
7. Strategies to promote adherence in the adult population
8. Application of reliable sources of drug information:
 Beers list of potentially inappropriate meds for the older patient
9. References & resources for further learning
Stages of adulthood
Patterns of health & illness
1
stages of adulthood
Young adulthood = 18 – 40 years of age
Middle adulthood = 40 – 65 years of age
Older adulthood = over 65 years of age
The United States' older adult population can be
divided into three life-stage subgroups:
young-old (approximately 65 –74)
middle-old (ages 75 – 84)
old-old (over age 85)
https://lumen.instructure.com; and Adams, Holland and Urban, 2014
patterns of health & illness
 Young adulthood; health status is usually good; absorption,
distribution, metabolism and excretion are at their peak;
relatively minimal need for px drugs (except contraception,
STI); risk of drug and alcohol use, especially among younger
adults
 Middle adulthood; increased stress; “sandwich generation”;
meds are often taken when therapeutic lifestyle measures
would be the optimal choice; health impairments (for
example) r/t CVD, HTN, DM2, obesity, arthritis, cancer,
depression, anxiety, childbirth, smoking/drug and alcohol use,
begin to surface around mid to late middle-age
 Older adulthood; improved therapies for disease and
improved living conditions have resulted in greater longevity;
polypharmacy is commonplace; overall general decline in
most body systems
Demographics of the aging population
2
United States
Overall life expectancy at birth 78.37
Male life expectancy at birth
75.92
Female life expectancy at birth 80.93
(2012 data)
Drug Therapy in Geriatric Patients:
Demographics of the aging population
BABY BOOMERS: BORN 1946 - 1964
People born in 1946 became 65 years old in 2011; retirement began.
Demographics of drug use
in the aging population
3
Demographics r/t drug use in the aging population:
Disproportionate drug use
• Drug use among adults age 65 years or older is
disproportionately high
•Represent 13% of current US population
•Consumers of 33% of prescription drugs
•Consumers of 40% of OTC drugs
• Ambulatory older adults use 2 to 4 prescription drugs
regularly
• Long-term care residents use an average of 7-8 medications
(Tindall, Sedrak & Boltri, 2014)
Demographics r/t drug use in the aging population:
Adverse Drug Reactions
Adverse Drug Reactions are seven times more likely
in the elderly
1/3 of drug-related hospitalizations
1/2 of drug-related deaths
Demographics r/t drug use in the aging population:
polypharmacy & associated risks
Greater prevalence in older adults due to increased prevalence
and/or severity of disease
Drugs to manage disease(s)
Drugs to manage symptoms (of disease or aging)
Drugs to treat side effects of other drugs
Multiple prescribers, excessive prescribing
Multiple pharmacies
Drug advertising (…pills to cure all…stay young..)
Older adult patients experience more adverse drug reactions
and drug-drug interactions than younger patients do
Demographics r/t drug use in the aging population:
common drugs in community-dwelling older adults
Classes most commonly used in community-dwelling older adults:
Analgesics
Diuretics
Cardiovascular drugs
Sedative hypnotics
(Tindall, Sedrak & Boltri, page 419, 2014)
?Antidepressants, anxiolytics
? Bowel meds? Fiber, stool softeners
Age-related physiologic changes
Age and/or disease- related physiologic changes
• profoundly affect pharmacokinetics
• whereas pharmacodynamic effects not understood
4
Age-related physiologic changes
affect organ systems, organs, and the molecular level
General reduction in function occurs throughout body
CNS and PNS
Vision, hearing, dexterity, balance, taste, olfaction,
Cardiac muscle, heart valves, blood vessels
Respiratory system
Gastrointestinal, liver, kidney, all vital organs
Hair, Skin and Mucosa
With the exception of estrogen and testosterone, the level
of hormone secretion remains relatively constant
Menopause (average age 51 years)
Male and female reproductive systems/ sexual
Musculoskeletal changes: skeletal muscle, bones
And more.(BOLD font indicates most vulnerable tissues, which cannot regenerate effectively)
Age-related physiologic changes
Individuals do not “age” uniformly at the same rate
Rate of aging and effects on physiology vary
“Biologic age” may not match “chronologic age”
Rate of change dependent on “lifelong health”
 Genetic makeup
 Lifestyle
 Health status
− presence or absence of disease, injury)
 Cardiovascular fitness
Age-related physiologic changes
pose unique considerations to geriatrics
Age-related changes COMBINE with disease-related changes
to impact pharmacokinetics and pharmacodynamics
Most commonly, effects of drugs are increased in older adults
Older adults are “more sensitive” to drugs than younger
adults
However, effects of some drugs may be decreased
(eg beta blockers)
Older adults show wider individual variation in responses
18
Which pharmacokinetic change is responsible for
most ADRs in older adults?
→ Reduced renal excretion
Age-related Physiologic changes: gastrointestinal changes
affect pharmacokinetics r/t absorption
Age-related changes to GI tract
 Reduced GI blood flow
 Reduced motility
 Atrophy of mucosa and glands
Reduces digestive secretions
Decrease in number of absorptive cells; decreased absorptive
surface area
gastric acid production may be unchanged or reduced
(ie increased pH)
delayed gastric emptying
Effect on pharmacokinetics
 The rate of absorption may slow with age, but overall percentage
(amount) absorbed from an oral med does not change with age
peak onset is delayed
Age-related Physiologic changes: body composition changes
affect pharmacokinetics r/t distribution
Body composition/ other changes & volume of distribution
Decreased percentage of lean body mass
Increased percentage of body fat
Storage depot for lipid-soluble drugs
Increased half-life of fat-soluble drugs
Decreased total body water
Increases serum concentration of water soluble drugs;
effects more intense
Reduced concentration of plasma proteins (especially serum
albumin)
Reduced protein binding of drugs and increased levels of free drug
In some people, albumin levels and “physiologic reserve” may be
significantly reduced and depleted
21
Age-related Physiologic changes: hepatic changes
affect pharmacokinetics r/t hepatic metabolism
Age-related changes to liver
—reduced hepatic blood flow
—reduced liver mass
—decreased activity of some hepatic enzymes occurs
Hepatic metabolism declines with age
Age – related changes combine with effects of concomitant
disease or social impacts such as decreased nutritional status
Half-lives of some drugs may increase, responses may be prolonged
Responses to some oral drugs may be enhanced
(eg drugs that undergo extensive first-pass effect)
Age-related Physiologic changes: renal changes
affect pharmacokinetics r/t renal excretion
Age-related changes to kidney:
Renal function undergoes progressive decline beginning in
early adulthood:
Reduction in number of functional nephrons,
Decreased glomerular filtration rate,
Decreased active tubular secretion;
Diminished ability to adapt to changes in electrolyte, acid levels
Reduction in renal blood flow
All the above lead to decreased renal excretion
Drug accumulation as a result of reduced renal excretion is the
most important cause of adverse drug reactions, drug-drug
interactions, and may lead to toxicity in older adults
23
Age-related Physiologic changes:
Assessment of Renal Function
Age-related Physiologic changes:
Assessment of Renal Function
Renal function should be assessed for all pts taking drugs that
are eliminated primarily by the kidneys
In older adults:
Use creatinine clearance to assess renal function
(rather than serum creatinine), because lean muscle mass
(source of creatinine) declines in parallel with kidney
function
Creatinine levels may be normal even though kidney
function is greatly reduced
25
Age-related Physiologic changes:
Assessment of Renal Function, cont’d
• Serum creatinine is not reliable but still important to assess
• Older adults have decreased muscle mass, and decreased
muscle metabolism, therefore less creatinine production
• Cockcroft – Gault Equation is adequate for most adult patients
with normal muscle mass and serum creatinine (Scr) < 4.5 mg/dL
Creatinine
clearance
(ml/min)
=
_140 - age in yrs x weight in kg _
72 x serum creatinine (% mg/100mL
(for women, multiply result by .85)
Age-related Physiologic changes:
Assessment of Renal Function: example of Cockcroft– Gault Equation
40 year old male weighs 72 kg
80 year old male weighs 72 kg
Years kg
cr cl =
(140 - 40) 72
72 (1.0)
cr cl =
(140 - 80) 72
72 (1.0)
Serum
Creatinine
cr cl = 100 ml/min
cr cl = 60 ml/min
* To estimate cr cl in women, multiply result by .85
Question 1
The nurse is assessing an 82-year-old patient before the
administration of medications. Which laboratory result
would provide the best index of renal this patient’s
function?
A. Serum creatinine
B. Blood urea nitrogen
C.Urinalysis
D. Creatinine clearance
28
Question 2
An older adult patient is taking a new prescription medication.
After reviewing the patient’s medical record, the nurse is most
concerned about an adverse drug reaction if what is
documented?
A. The patient is currently taking eight prescription medications.
B. The patient’s urinary creatinine clearance is 70 mL/min/1.73 m2.
C. The patient regularly takes herbal and dietary supplements.
D. The patient takes a medication with a high therapeutic index.
29
Age-related physiologic changes
impact pharmacodynamics
Alterations in receptor properties may underlie altered sensitivity
to some drugs. Examples:
Some drugs have more intense effects in older adults
Warfarin and certain central nervous system depressants
→ possibly due to increases in number of receptors,
affinity or both
Beta blockers are less effective in older adults, even in the
same concentrations
→ possible reduction in number of beta receptors ,
affinity of beta receptors for beta-receptor blocking
agents, or both
30
Adverse drug reactions and drug-drug interactions
are HIGH in the older adult patient population
Why?
What do ADE/ ADR look like in the elderly?
5
Drug Therapy in Geriatric Patients:
Predisposing Factors that increase rate of ADR
Drug accumulation secondary to reduced renal function is the
most important cause of adverse drug reactions and drug-drug
interactions in older adults
Polypharmacy
Greater severity of illness
Multiple pathologies
Greater use of drugs that have a low therapeutic index (for
example, digoxin)
Increased individual variations secondary to altered
pharmacokinetics
Inadequate supervision of long-term therapy
Poor patient adherence
32
Drug Therapy in Geriatric Patients:
Examples of ADE/ ADR
May be undetected in older adults because they can mimic
characteristics of problems, disease, or symptoms commonly
present in the elderly
Symptoms of ADR in older adults are often nonspecific
Examples:
−Oversedation
−Cognitive changes such as confusion
−Dizziness
−Hallucinations
−Accidents/ Falls
−Bleeding
What measures can the nurse use to decrease
incidence of adverse drug events/ reactions
and drug-drug interactions?
6
Drug Therapy in Geriatric Patients:
Measures to Reduce ADE/ ADRs
Consider pharmacokinetic and pharmacodynamic changes
due to age
Use the simplest regimen possible:
− Consider illnesses and multiple-drug therapy
Periodically review the need for continued drug therapy
Take steps to promote adherence and to avoid drugs on the
Beers list
Monitor the patient’s clinical response, adverse effects,
Monitor plasma drug levels when appropriate
Monitor for drug-drug interactions
Provide effective teaching to pt and family/ caregiver
Encourage the patient to dispose of old medications
35
How can the nurse decrease the incidence of
adverse drug reactions and drug-drug interactions
based on altered pharmacokinetics?
How can the nurse decrease incidence of
adverse drug reactions and drug-drug interactions
based on altered pharmacoKINETICS?
Identify the organs involved
Monitor organ functioning
Liver-
PT/INR good indicators of hepatic function
AST, ALT are markers for hepatic inflammation
Ammonia
albumin
Kidneys – creatinine clearance
Assess for symptoms that suggest a decline in organ function
Assess for desired and adverse responses to the drug
How can the nurse decrease the incidence of
adverse drug reactions and drug-drug interactions
based on altered pharmacodynamics?
How can the nurse decrease the incidence of
adverse drug reactions and drug-drug interactions
based on altered pharmacodynamics?
Differences in receptor number and binding = UNPREDICTABLE
Assess for desired and adverse responses to the drug
Use caution with drugs that can have serious adverse effects,
especially with low therapeutic index drugs
Use less toxic analgesics first (e.g., acetaminophen versus NSAID)
Watch for delayed signs of drug-related toxicity
Start with low doses of meds… titrate up as needed
at appropriately spaced time intervals, carefully monitoring for effect
Remember: it takes between 4 – 5 doses of meds administered at
properly spaced/timed intervals (r/t half-life) to achieve plateau
Start low . . . . Go slow!
How can the nurse decrease the incidence of
adverse drug reactions and drug-drug interactions
based on multiple severe illnesses & multi-drug therapy?
How can the nurse decrease the incidence of
adverse drug reactions and drug-drug interactions
based on multiple severe illnesses & multi-drug therapy
Assess polypharmacy
Obtain a thorough drug history that includes:
prescription, OTC, herbals, & supplements
doses, timing, routes, reason, and prescriber
Create a complete list
 Share list with all prescribers and pharmacist
Teach patient when to contact the prescriber
Teach to get meds from ONE pharmacy and work with pharmacist
Identify risks for difficulty and develop individualized interventions
that address these problems.
Teach pt to dispose of old medications
How can the nurse decrease the incidence of
adverse drug reactions and drug-drug interactions
by addressing poor adherence?
 Prevalence of non-adherence ranges 40-70%
7
 Nonadherence issues may be intentional or
unintentional
 First step: identify contributing factors
How can the nurse decrease the incidence of
adverse drug reactions and drug-drug interactions
by addressing poor adherence?
Promoting adherence with Unintentional Nonadherence
Simplify drug regimen
Clear and concise verbal and written instructions
Appropriate dosage form
Containers should be clearly labeled and easy-to-open
Daily reminders, timers, pill dispensers
Support system
Frequent monitoring
43
How can the nurse decrease the incidence of
adverse drug reactions and drug-drug interactions
by addressing poor adherence?
Promoting Adherence with Intentional Nonadherence
Most cases (75%) of nonadherence are intentional
Reasons include the following:
High cost of drugs, side effects, and the patient’s belief
that the drug is unnecessary or that the dosage is too high
44
How can the nurse decrease the incidence of
adverse drug reactions and drug-drug interactions
by addressing poor adherence?
Is non-adherence due to Health Status?
Vision
Hearing
Dexterity
Cognition
Depression
Finances
How can the nurse decrease the incidence of
adverse drug reactions and drug-drug interactions
by addressing poor adherence?
Is non-adherence due to Behavioral/ Attitudinal Factors?
Social isolation
Health beliefs (perceptions! Self and societal)
severity of illness
susceptibility to illness
side effects and efficacy of treatment
Financial status
How can the nurse decrease the incidence of
adverse drug reactions and drug-drug interactions
by addressing poor adherence?
Is non-adherence due to Treatment Factors?
Dosing frequency
Complexity
Duration of treatment
Number of medications
Types of medications (dosing forms)
Drug Therapy in Geriatric Patients:
Assessment of Adherence
Ask client to bring all medications to clinic
Open-ended questions regarding each medication
what drugs are they taking? how are they taking?
Direct questions:
• “do you ever forget to take your medicines?”
• “how many times in the last week have you missed a dose?”
• “when you feel better do you stop taking your medicines”
• “sometimes if you feel worse do you stop taking your
medicines?”
Pharmacy refill patterns
Observation of home environment
Question 3
An older adult patient frequently forgets to take an oral
medication that has been prescribed to be taken three times per
day.
Which action by the nurse is best?
A. Assess the patient’s ability to swallow the medication.
B. Arrange for a neighbor to call the patient three times a day.
C. Call the prescriber for a sustained-release form of the drug.
D. Give the patient verbal and written instructions about the drug.
49
Certified Geriatric Pharmacists
Application of reliable sources
of drug information
8
Beers Criteria for Potentially Inappropriate
Medication Use in Older Adults
updated 2015, American Geriatric Society
53 classes of drugs in 3 categories
Potentially Inappropriate Medication Use in Older Adults
Drugs that should be Used with Caution due to drugdisease or drug-syndrome interactions
Drugs that may exacerbate condition
Is a safer drug available?
 “Potentially Inappropriate”
 http://geriatricscareonline.org/ProductAbstract/american-geriatrics-societyupdated-beers-criteria-for-potentially-inappropriate-medication-use-in-olderadults/CL001
Drug Therapy in Geriatric Patients:
Examples of medications from the “Beers list”
First-gen antihistamines – anticholinergic effects
Non-selective COX inhibitors – risk of renal damage and GI
bleed
Clonidine as first-line antihypertensive – risk of CNS effects
and orthostatic hypotension
TCAs – sedating, anticholinergic, can cause orthostatic
hypotension
Benzodiazepined (BZDs) – increased sensitivity to effects, risk
of oversedation, cognitive impairment, falls
Drug Therapy in Geriatric Patients: TAKE-AWAY MESSAGES
►Nursing action tips:
*
 Collaborate with patient, family, & prescriber on treatment goals
 Teach the role of drug therapy in reaching goals
 Identify and address contributing factors, barriers to adherence
 Problem-solve on an individualized basis
 Individualized medical management is essential
 Each patient must be monitored for desired and adverse responses
 Regimen must be adhered to (ie agreement between what the
provider thinks the pt is taking vs. meds the pt actually takes)
 Goals of treatment:
Reduce symptoms and improve quality of life
54
Drug Therapy in Geriatric Patients:
References & resources for further learning
9
 American Geriatric Society
 Centers for Disease Control and Prevention
 The State of Aging and Health in America (2013)
http://www.cdc.gov/aging/pdf/state-aging-health-in-america2013.pdf
http://www.cdc.gov/aging/index.html
 Older Americans (2012): Key Indicators of Well-being
http://agingstats.gov/agingstatsdotnet/Main_Site/Data/2012_Doc
uments/Docs/EntireChartbook.pdf
 American Association of Retired Persons (advocacy)
 http://depts.washington.edu/geront/
Geriatric Case
 Ms. Giordano - 67 YO F
 How would you approach
your analysis of this med list?
 PMH: osteoarthritis both knees and the right
What resources would you
hip, breast cancer, spondylolisthesis with
use?
chronic lumber pain, depression
 Medications
Sertraline 75 mg, daily
Amitriptyline 25 mg PRN for sleep
Acetaminophen 500 mg, q8h, for OA
and back pain as needed
Naproxen, 500 mg, bid for OA pain as
needed
Multivitamin
Vitamin D 2000 IU/day
 What problems do you see?
 What are potential solutions?