analysis of various effects of polypharmacy in geriatrics...
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Analysis of Various Effects of Polypharmacy in Geriatrics in the
Department of General Medicine at Tertiary Care Teaching Hospital
S.Ahmed Hussaini1, *Sameera Gouher1, Shawana Nazim1, Marya Fairdous1,
Syeda Kareema Sobia1, Musa Khan2 1 MESCO College of Pharmacy, Mustaidpura, Karwan Road, Hyderabad.
2 Department of General Medicine, Osmania General Hospital (OGH), Afzal Gunj, Hyderabad,T.S,
Email: [email protected]
Corresponding author: *Sameera Gouher
ABSTRACT: The principle aim of our study was to analyze prevalence and the effects of Polypharmacy in
geriatric patients in a tertiary care setup. This study was carried out for duration of 6months at the Inpatient
department of General medicine in Osmania general hospital, Afzalgunj, Hyderabad.
The data of 150 patients was collected by using prepared forms and was examined to explore the relationship
between polypharmacy in geriatrics and adverse clinical outcomes through drug interactions and adverse drug
reactions. The effects of polypharmacy on patient’s awareness level and prescription adherence had also been
analysed.
In the data collected the following out comes were recorded of 150 patients among which the most common
subject of our study lies in between 60 – 65 yrs of age group. Out of 150 patients more than 102 patients were
given more than 7 – 8 and more than 8 medications. Very few patients received less than 3 - 4 medications.
Majority of adverse drug reactions were observed in patients given 7 – 8 and more than 8 medications. There
was more number of moderate drug interactions with an increase in medications. A total of 140 patients were
found to be satisfied with the treatment given.
On analyzing the results it was noted that polypharmacy is very common in old patients of above 60years and
observed that number of medications was factor associated with adverse drug reactions, drug interactions,
patient adherence and awareness of medications.
INTRODUCTION
POLYPHARMACY
Polypharmacy is the use of four or more medications by a patient, generally adults aged over 60years.
Polypharmacy is most common in the elderly, affecting about 40% of older adults living in their own homes.
the prevalence of many diseases increases with age. Therefore elderly people often suffer from multiple
coexisting health problems. Many of this are chronic problems which required long term drug therapy and
sometimes combination drug therapy; so older people are frequently prescribed multiple medications
(polypharmacy). Studies have consistently reported a positive association between the number of medication
and the risk of adverse drug reactions (ADR’S), drug interactions, unplanned hospital admissions and
medication non-compliance therefore although the use of multiple medications may be unavoidable in patients
with multiple co-existing medical conditions, care must be taken to avoid unnecessary polypharmacy.
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Volume 7, Issue IX, September/2018
ISSN NO: 2236-6124
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GERIATRICS
Geriatrics is the branch of medicines that is concerned with the medical and social aspects of health and illness
in the elderly. The term “elderly” generally refers to people aged 65years and above. However, the
physiological changes associated with ageing occur gradually over a lifetime, with significant patient-to-patient
variability, so the choice of 65years is arbitrary, and sometimes the definition is extended to include people
aged 60years and above.
The use of multiple medications is recognized as an increasingly serious problem in the current healthcare
system. Older people have higher rates of chronic illness and are more likely to be taking multiple medications.
Polypharmacy increases the risk of adverse drug events such as falls,
Confusion and functional decline.
Changes in physiology and social and physical circumstances contribute to the risk of adverse drug events.
Older people are more likely to experience poor vision, hearing and memory loss and have altered metabolic
rates, such as declining renal function. Adverse reactions may go undetected because symptoms may mimic
problems associated with older age such as forgetfulness, weakness or tremor. Adverse reactions may also be
misinterpreted as a medical condition and lead to the prescription of additional drugs.
Concerns about polypharmacy include increased adverse drug reactions, drug interactions, prescribing
cascade and higher costs. Polypharmacy is often associated with a decreased quality of life, decreased mobility
and cognition.
It is well accepted in pharmacology that it is impossible to accurately predict the side effects or clinical effects
of a combination of drugs without studying that particular combination of drugs in test subjects. Knowledge of
the pharmacologic profiles of the individual drugs in question does not assure accurate prediction of the side
effects of combinations of those drugs.
Whether or not the advantages of polypharmacy (over monotherapy) outweigh the disadvantages or a risk
depends upon the particular combination and diagnosis involved in any given case.The use of multiple drugs,
even in fairly straightforward illnesses, is not an indicator of poor treatment. A perfectly legitimate treatment
regimen could include, for example, the following: a statin, an ACE inhibitor, a beta-
blocker, aspirin, paracetamol and an antidepressant in the first year after a myocardial infarction.
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ALTERED DRUG RESPONSE:
Elderly patients, especially the very old (over 75years) and the frail, tend to be more sensitive to the effects of
medications compared to younger adults. This is a result of physiological changes that occur with aging
resulting in altered Pharmacokinetics and Pharmacodynamics, Older patients are therefore more prone to
adverse effects and often require low doses. Moreover the elderly patients have higher rates of co morbidities
and conditions that can alter drug metabolism and excretions therefore there may be increased incidences of
adverse events found in them.
ADR’S may present insidiously without typical symptoms in the elderly and therefore they can be difficult to
distinguish from new onset of illness. This can result in misdiagnosis and the introduction of an additional drug
to treat the symptoms there by contributing to Polypharmacy.
INAPPROPRIATE PRISCRIBING
Inappropriate prescribing by the physicians is one of the problems apart from this inappropriate drug selection,
under prescribing and over prescribing is also common.
PATIENTS’ NON-COMPLAINCE
Compliance is defined as the extent to which the behavior of the patients coincides with the prescribe drug
regimen. Non-compliance with the drug therapy is most common among geriatrics due to the following…
a) Multiple drug prescriptions
b) Polypharmacy
c) Complex drug regimen
d) Cognitive impairment
e) Lack of proper adequate patient counseling
f) Poverty and illiteracy.
ADVERSE DRUG REACTION
Incidence of ADR’S among the elderly is relatively higher in India due to self medications and lack of proper
patient counseling. polypharmacy coupled with multiple diseases and inappropriate in elderly may also
increases the risk of ADR’S.
BASIC PRINCIPLES OF DRUG THERAPY IN GERIATRICS:
1) Saftey and efficacy
Providing safe and effective treatment is the primary objective of drug therapy in elderly to fulfill this
objectives through the knowledge of pharmacokinetics and pharmacodynamic aspects is essential in order to
select an appropriate drug therapy which can prove to be safe, beneficial and efficacious.
2) Choice of an appropriate drug
Various pharmacokinetics and pharmacodynamic parameters should be taken into consideration while
choosing the drugs in elderly. As geriatrics are at an increased risk of ADR’s, the drugs chosen should be safe,
effective and posses less risk of drug related adverse effect.
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Drugs effecting multiple organs should be avoided the prescriber should also consider other coexisting diseases
or disorder while prescribing the medication
3) Dose adjustment
Since geriatrics require less doses of drugs therefore the prescriber should start with a low dose while
prescribing, the prescriber should always abide by the golden rules go low and go slow.i.e.,start with a low dose
and titrate upwards slowly as tolerated by the patients.
Table 1: Dosage adjustment in Geriatrics
4) Drug history
Drug history of elderly patients should be taken into consideration to avoid adverse effects and potential drug
interactions.
5) Concomitant medical illness
As elderly people suffer from multiple disorders such as cardiac failure, renal failure etc., concomitant disease
should be taken into consideration while prescribing drugs so as to minimize the risk of adverse effects.
6) Packaging and labeling
Majority of elderly patients with arthritis find it difficult to open containers and blister packs while those with
visual impairment are unable to read and follow the written instructions on labels. Hence, for geriatric patients
medicines shouled be dispensed in easy-to-open containers that are clearly labeled using large prints and colour
coders.
7) Choice of suitable dosage forms
Since it is quite difficult geriatric patients swallow tablets and capsules therefore, syrups, suspensions and
effervescent tablets should be prescribed.
DRUG
NORMAL DOSE IN
ADULTS
DOSE ADJUSTMENTS IN
GERIATRICS
Cimetidine 300 mg q.i.d Plasma clearance is drastically decrease
the oral dose should be reduced by 1/3
to 1/2
Allopurinol 800 mg /day Dose is decreased in renally impaired
patients
Diazepam 2 to 10 mg b.i.d to q.i.d Dose is reduced to 2 to 2.5 mg O.D or
b.i.d
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Table 2: Prescription Risk in Geriatrics
Class Drug Prescription risks in elderly
Analgesics Indomethacin Produces CNS adverse effects.
Antidepressants
___ Produces severe anticholinergic and sedative effects.
Antihistamines ___ Produces anticholinergic effects, hence should be avoided.
Cardiovascular
drugs
Digoxin
Dipyridamole
Methyldopa
Decreases renal clearance in elderly.
Produces orthostatic hypotension in elderly. May cause
bradycardia and aggravate depression in geriatric patients.
8) Avoiding polypharmacy
Avoiding polypharmacy and drug prescribing cascade keeps a check on adverse effects, drug interactions and
nocomplaince.
Example: piroxicam (NSAID) indicates in inflammation and pain is associated with edema and hypertension.
misconstruction of these adverse effects as a new medical conditions and prescribing another drug such as
chlorthalidone (diuretic) to relieve the oedema may results in newer adverse effects like low serum k+ levels,
dizziness, cramps etc. these adverse effects may further be misinterpreted requiring medical intervention with
another drug.
9) Record keeping
Maintenance of the past and presented drug record of patients is very important as this helps the physician to
know about the patients response to prevent medications, presence of allergies, complications etc.
10) Cost effectiveness
Generally, most of the geriatric populations either have fixed incomes or are dependent on their families.
Therefore, while prescribing drug, physicians should also take the cost factor into account. A drug which is
cheaper and effective should be preferred while prescribing.
11) Monitoring of drug therapy
Close and careful monitoring of drugs therapy and periodic review of the prescriptions helps to avoid
undesirable drug effects and would provide better results.
PRECAUTIONS IN DRUG USAGE IN GERIATRICS
Precautions to be taken by health professionals
1) Prescribing two or more drugs for a single disorder should be avoided without avoiding the drug with known
clinical benefits.
2) Drugs whose potential benefits are less when compared to their adverse effects should be avoided.
3) Drugs that commonly produce harmful effects in elderly should be avoided.
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4) Selection and adjustment of dosage should be based on the age, weight, liver or renal function and other
conditions of the patients.
5) Non-pharmacological or non-drug approaches should be used for symptoms like anxiety, chronic pain
insomnia and in conditions which can be treated by modifications in lifestyle.
Example: Reduction in sodium intake and loss of weight can reduce the use of antihypertensive drugs in about
40% individuals with high B.P.
6) Safest possible drug should be chosen and the drug dosge should be low especially when administered a new
drug so as to reduce the adverse effects associated with it.
Example: CNS active drug used in low doses resulted in leser adverse effects when compared to high doses.
7) patient’s drug regimen should be evaluated periodically for,
a) Simplifications of drug dosage regimen.
b) Determining the interaction between the drug and minimizing side effects.
8) Usage of drugs with limited therapeutic benefit and high risk of adverse effects should be avoided.
Example: Digoxin with its low therapeutic benefit may cause toxic effects in patients with renal impairment or
temporary dehydration.
Precautions to be taken by patients
1) patients should follow the directions for taking medications and seek help from care givers, doctors, family
members or pharmacists especially when they are,
a) Taking three or more drugs, non-prescription drugs, herbal drugs and dietary supplements.
b) Visiting several different health care professionals or clinics for care.
c) Living alone.
d) Using both community and online pharmacies.
e) Having short term memory or memory problems.
2) They should always read the label of the medicine carefully.
3) The medicines’ name and direction for use said by the physician should be checked at the pharmacist after the
prescription is filled.
4) They should strictly adhere to the prescribed regimen.
5) Concomitant use f dietary supplements, herbal products, non-prescriptions drugs that may significantly interact
with prescribed drug should be avoided.
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6) Intake of foods and beverages that have potential to interact with drugs should be avoided.
Examples:
i. Grape juice – Antihypertensive drugs
ii. Milk and milk products – Antibiotics and antifungal drugs
Table 3: Drugs Contraindicated in Elderly
DRUGS ADVERSE EFFECTS PRODUCED
Tetracycline Increase in blood urea levels in case of renally impaired patients.
Reserpine Depression
Cabenoxolone CHF and oedema
Barbiturates Dilemma
Streptomycine Ototoxicity
Guanethidine Postural hypotension
Pentazocine Dilemma
Chlorthalidone Incontinence, prolonged dieresis
Bethanidine Severe postural hypotension
Debrisoquine Postural hypotension
NEED OF STUDY
Geriatric patients are compounded multiple complications and co morbid conditions due their altered
physiological changes, they may highly require the use of multiple drugs for their conditions but their capacity
to metabolise and eliminate the given drugs also get altered. So treatment in these patients gets complicated
therefore should be done highly through the evidence gathered through different researches.
During our review and search for articles on this subject we found that there is lack of comprehensive research
done covering different aspects and effects of polypharmacy in geriatrics, so we found that there was an
absolute need to carry out a study to assist in practicing geriatrics.
This study had analysed the prevalence of polypharmacy in a tertiary care hospital (Osmania General Hospital)
and its effects in increasing patient’s mortality and morbidity. As previous studies also suggested patient’s
medication compliance and prescription adherence is low in polypharmacy practice that was also analysed.
Through the process counselling the patient’s adherence was improved and the adverse effects and drug
interactions were reported or reduced with consultation with the physicians.
This study can be helpful for medical professionals in understanding the consequences of polypharmacy
practices so that it could reduce poor effects and improve management of disease among geriatrics.
AIMS AND OBJECTIVES
The aim of our study is to analyze prevalence and the effects of polypharmacy in geriatric patients.
The purpose of this study was to explore the relationship between polypharmacy and adverse clinical
outcomes through drug interactions and adverse drug effects.
The effects of polypharmacy on patients awareness level and prescription adherence were also analysed.
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Study Design: An Observational prospective study.
Sample Size: Patient size selected for the study is 150.
Site of Study: The study was conducted in the General medicine department Osmania
General Hospital (Afzalgunj, Hyderabad, Telangana,) which is
Study Duration: The study was carried out for the period of 6 Months.
Plan of Work:
During the study researchers had collected data on suitable data collecting form from hospital case sheets and
questionnaire prepared to achieve objectives required to accomplish aim of the study.
To estimate prevalence of polypharmacy and summaris
geriatric patients.
Data was collected based on number of patients receiving polypharmacy, their gender, prescription pattern of
drugs will be derived.
As the increase in number of medications prescribe
adherence to their medications, so through questionnaire data is collected and analysed to asses the patient
awareness and adherence.
To count the number of adverse effects or complications developed wh
relation with the increase of number of medication administered.
With the use polypharmacy there may be chances of Drug interactions so
and its relation with increase in number of medica
Table 4: Tabular description showing the Age Groups of Subjects enrolled in the Study
Table 5: Tabular description showing
MALE
116
77.3%
METHODOLOGY
An Observational prospective study.
Patient size selected for the study is 150.
The study was conducted in the General medicine department Osmania
General Hospital (Afzalgunj, Hyderabad, Telangana,) which is a tertiary care hospital.
The study was carried out for the period of 6 Months.
During the study researchers had collected data on suitable data collecting form from hospital case sheets and
questionnaire prepared to achieve objectives required to accomplish aim of the study.
To estimate prevalence of polypharmacy and summarise prescription pattern of drugs
Data was collected based on number of patients receiving polypharmacy, their gender, prescription pattern of
As the increase in number of medications prescribed to patients may effect on the patient awareness and
adherence to their medications, so through questionnaire data is collected and analysed to asses the patient
To count the number of adverse effects or complications developed which were than analysed for their
relation with the increase of number of medication administered.
With the use polypharmacy there may be chances of Drug interactions so the prevalence
and its relation with increase in number of medications prescribed to the patient is analysed.
Table 4: Tabular description showing the Age Groups of Subjects enrolled in the Study
Tabular description showing the gender of Subjects enrolled in the Study
FEMALE
34
22.6%
The study was conducted in the General medicine department Osmania
tertiary care hospital.
During the study researchers had collected data on suitable data collecting form from hospital case sheets and
questionnaire prepared to achieve objectives required to accomplish aim of the study.
e prescription pattern of drugs prescribed in
Data was collected based on number of patients receiving polypharmacy, their gender, prescription pattern of
d to patients may effect on the patient awareness and
adherence to their medications, so through questionnaire data is collected and analysed to asses the patient
ich were than analysed for their
the prevalence of such interactions
tions prescribed to the patient is analysed.
Table 4: Tabular description showing the Age Groups of Subjects enrolled in the Study
enrolled in the Study
FEMALE
22.6%
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Table 6: Tabular description showing
Fig 2: Graphical Presentation showing the no. of medications of Subjects enrolled in the study
Table 7: Tabular description showing the
Fig 2: Graphical Presentation showing the
0
10
20
30
40
50
60
3 to 4
NO. OF PATIENTS
0.00%
20.00%
40.00%
60.00%
80.00%
100.00%
3 to 4
No. ofpatients
Tabular description showing the no. of medications of Subjects
Fig 2: Graphical Presentation showing the no. of medications of Subjects enrolled in the study
Table 7: Tabular description showing the awareness and adherence of Subjects
Fig 2: Graphical Presentation showing the awareness & adherence of Subjects enrolled in the study
3 to 4 5 t0 6 7 to 8
NO. OF MEDICATIONS
5 to 6 7 to 8 >8
Awareness for doses % of Pts
Awareness for frequency % of Pts
Awareness for instructions % of Pts
Reported missing dose % of Pts
enrolled in the Study
Fig 2: Graphical Presentation showing the no. of medications of Subjects enrolled in the study
awareness and adherence of Subjects enrolled in the study
of Subjects enrolled in the study
>8
Awareness for doses % of Pts
Awareness for frequency % of Pts
Awareness for instructions % of Pts
Reported missing dose % of Pts
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Table 7: Tabular description showing the
study
Fig 3: Graphical Presentation showing the
study
Table 9: Tabular description showing the
0
10
20
30
40
50
60
No issue of compliance
No. of patients
Table 7: Tabular description showing the Compliance and Satisfaction of Subjects
: Graphical Presentation showing the Compliance and Satisfaction of Subjects enrolled in the
Tabular description showing the Adverse Drug Reactions of Subjects
No issue of compliance
Satisfied with the current treatment
issue of compliance Not satiesfied with the treatment
of Subjects enrolled in the
of Subjects enrolled in the
of Subjects enrolled in the study
Not satiesfied with the treatment
3 to 4
5 to 6
7 to 8
>8
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Fig 4: Graphical Presentation showing the
Table 10: Tabular description showing the
Fig 5: Graphical Presentation showing the
0
5
10
15
20
03 to 04
No. of patient
0
10
20
30
40
50
60
70
03 to 04
No. of patients
Presentation showing the Adverse Drug Reactions of Subjects enrolled in the study
Tabular description showing the Drug Interactions of Subjects enrolled in the study
: Graphical Presentation showing the Drug Interactions of Subjects enrolled in the study
05 to 06 07 to 08 >8
05 to 06 07 to 08 >8
of Subjects enrolled in the study
enrolled in the study
Subjects enrolled in the study
>8
No ADRS
1-2 ADRS
3-4 ADRS
5-6 ADRS
>6 ADRS
>8
No ADRS
1-2 ADRS
3-4 ADRS
5-6 ADRS
>6 ADRS
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Results and Discussion
Our study demonstrates that polypharmacy is very common in old patients (above 60 yrs) and we have
observed that number of medications was a factor associated with difference in clinical outcomes,
independently of the age. Type of medications prescribed and accompanied co-morbidities. As the number of
co-morbid conditions was increasing the number of prescription medications will also get increased but that
also led to increased frequency of Drug Interactions & Adverse drug reactions. Sometimes it might also be due
to the medications co-morbid conditions get evolved.
our study has shown that out of 150 subjects males (77.3%) were more in count when compaired to females
(22.6%). the age groupm of 60 – 65 years (79 ptns) was having more number of patients similar to the study
done by Maher RL, et al.-2014. On evaluatiojn of the collected samples it was found that categories like 7 – 8 (49 ptns) and more than 8 drugs
(55ptns) have more number of patients respectively. Which accounts for more number of moderate drug
interactions ( medscape drug interaction checker) which is similar to study conducted by Wang R – 2015. Numbers of
moderate reactions were found to be more in number (126 DI’s) rather than major (06) and minor (19).
Medscape Drug Interaction Checker
Mild – Minimally clinically significant minimize risk assess risk and considered on alternative drug.
Moderate – Moderately clinically significant usually avoid combinations use under special circumstances.
Major – Highly clinically significant avoid combinations.
A total number of 150 patients were assessed for their knowledge regarding the medication compliance and
prescription adherence out of which categories like 7 – 8 (83.6%) and more than 8 drugs (80%) have more
number of patient’s adherence respectively. which is incontrast with the survey done by Walid F. Gellad – 2012
Assessment was conducted to identify Adverse Drug Reaction in the recorded prescriptions and was observed
that, as the number of medications were increasing their were also an increase in number of Adverse Drug
Reactions generally under the category of 7 – 8 (44 ptns) and more than 8 drugs (57 ptns) have more number
of patients respectively which is similar to the study done by Stephen J. Evans- 2014 It was analyzed that as no. of co-morbid conditions were increasing there was an increase in number of
medications.Upon the assessment of the recorded data the category of dugs i.e., 7 – 8 and more than 8 drugs
were more prone to Adverse Drug Reactions and Drug Interactions.
CONCLUSION
This study provides an insight in analyzing the effects of polypharmacy in geriatrics which is very common in
old patients and observed that number of medications was a factor associated with difference in clinical
outcomes independently of age, type of medications prescribed and accompanied co morbidities. The
discontinuation of medications both when risks outweigh benefits and when regimens are not feasible or do
not aligns with the goals.
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The risks of adverse drug reaction and drug interactions can be minimize through identifying the prevalence of
this potential problem in high risk population and by increasing awareness among patients and healthcare
professionals. Physicians and clinical pharmacist have the potential to combating this problem through a
variety of interventions such as reducing number of medications taken, reducing number of doses taken,
increasing patient adherence, preventing adverse drug reactions, drug interactions and improving patient
quality of life.
When prescribing drugs for elderly general practitioner’s should to take into account the specificities of the
elderly, their biological and chronological framework and should always apply the principles of rational,
conservative and evidence based pharmacotherapy. Analyzing the results, we conclude that polypharmacy is
very common in old patients and observed that number of medications was a factor associated with adverse
drug reactions, drug interactions, patient adherence and awareness of medications.
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