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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
Asian Journal of Pharmaceutical Technology & Innovation
ISSN: 2347-8810
Research Article
Received on: 02-11-2014
Accepted on: 15-11-2014
Published on: 15-12-2014
Assessment of Drug Related Problems in
Geriatrics with Polypharmacy and Risk
Measurement
Corresponding Author:
* P. Samarasimha Reddy,
* Md. Waseemuddin
Raghavendra institute of
pharmaceutical education and
research (RIPER)
Anantapur Dt, Andhra Pradesh,
India – 515 721
Md. Waseemuddin*, P. Samarasimha Reddy*
ABSTRACT
Drug related problems are an essential term in the world of
pharmaceutical care. Other terms can be used for the same concept,
such as medication errors, but this term is different from drug
related problems. The fact that the elderly take more medications
for the treatment of several diseases makes them more susceptible
to the occurrence of adverse reactions. The errors refer to the
mistakes in the process that could lead to problems. Drug related
problems
can
originate
when
prescribing,
dispensing
or
taking/administering medicines. The aim of this study was to
analyze the Drug related problems and usage of drugs among
geriatric patients living at old age homes. The results of study
shows that males (59.33%) are more affected with chronic diseases
than females(41.67%). Drug related problems due to drug
interactions followed by drug overdose. Most of the interventions
for inappropriate drug contraindications, adverse drug reactions
were rectified and improved(100%) followed by other problems.
our study concluded that pharmacist can prevent clinical drug
related problems by making a suitable intervention.
*Email [email protected]
Key-words: Polypharmacy, drug reaction, Polypharmacy risk
measurement
Cite this article as:
Md. Waseemuddin, P. Samarasimha Reddy, Assessment of Drug Related Problems in Geriatrics with Polypharmacy and
Risk Measurement, Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014.
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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
Introduction
GERIATRICS
Geriatrics is the branch of general medicine concerned with the clinical, preventive, remedial and
social aspects of illness in the elderly. Officially the term elderly or geriatrics refers to the person or
patient aged 65 years and above. The term elderly is always related to physical incapacity, biological
deterioration, disabilities and psychological failures. Over the previous centuries, there has been a
dramatic rise in the number and proportion of elderly people in the developed countries as well as
developing countries. Developing countries are aging faster than the developed ones and the disability
rates among elderly population were declining in the developed countries but increasing in the
developing countries. Chronologically the elderly can be classified as Young old (65-74 years), old (75-84
years), old-old (85-94 years) and elite old or chronologically gifted (95 years and older).
Population aging is a fundamental transformation of human society. The rising life expectancy at
birth is one of the major achievements of 20th century. But instead of rejoicing over the favorable
demographic indicator, the world is caught in an "age quack" (www.frontlineonnet.com) As life
expectancy increases there is a need to improve the health, quality of life, discovery of new treatment,
prevention strategies, improving health behaviour and the medication use. The increase in life
expectancy has posed one of the toughest challenges to be met by the health care professionals and by
the society. The increases in life expectancy too have been substantial. In 1950, a 65 year man could
expect an average to live until the age of 78 years, now it is increased to 81 years and if current trends
continue, by 2025 the expectancy increased to 83 years) and by 2060 it will be increased to 85 years.
Women's life expectancy is projected to increase about the same way from 81 years to roughly 85 years
today, 86 years in 2025 and 88 years in 2060.
In US, the elderly constitute about 13% of population, but they consume about 30% of all
prescribed medications Dr. Brazeau quoted that "according to Allard, individuals over the age of 75 years
took an average of 6 different medications".Data from Third National Health and Nutrition Examination
Survey (NHANES III) reveals that 74% of elderly people use prescription medications f Among Persons
aged 65-74 years) half of them use 2 or more prescription drugs, 12% use 5 or more prescription drugs
and those aged 75 and above, 60% use at- least two prescription drugs and 16% use at least five. Recent
studies indicated that as much as 28% of hospitalizations of elderly patients are related to medication
misadventures. 95% of these events are predictable and approximately 66% are preventable. (Mildred et
al, 2005)
If drug related problems were ranked as a disease by cause of death, it would be the 5tn leading
cause of death in United States (www.premierinc.com). According to a news release from Duke
University medical center, Durham NC, many Americans older than 65 years of age have prescriptions for
medications considerable potentially risky for elderly (www.findarticles.com). The inappropriate
medication
use
was
one
of
the
reasons
for
polypharmacy
(www.globalaging.org.health/world/2004/growing.htm). According to a study released by the university
of Arizona Health Sciences center for education and research on therapeutics (CERTS) 21% of elderly
patients filled a prescription for more than one drug considered potentially inappropriate for person over
the age of 65 years.
According to Indian council of medical research (ICMR) studies, the paramedics can be trained to
recognize major physical illness and find appropriate medical, community or social interventions among
elderly population. According to Beer "the interventions of the health care providers decreases both drug
related costs and overall cost thus minimizing the drug related problems". The prevalence of many
disease increases with advancing age and as a result, elderly population often suffer from multiple
coexisting conditions. Elders tend to be more sensitive to the effect of medication compared to younger
patients. This is a result of Physiological changes that occurs with advancing age. resulting in altered
pharmacokinetics and pharmacodynamics for many drugs. Many of the problems that affect the elderly
are of chronic nature and may require long term drug therapy. As a result of increased disease
prevalence, older people tend to use more medications compared to younger people. So polypharmacy is
of greater concern in the geriatric population (Beers, MH 2005, the Merck manual of geriatrics).
PHARMACODYNAMIC CHANGES
There is some evidence in elderly of altered drug response. Altered response may be due to
changes in receptor numbers, changes in receptor affinity, post receptor alterations, age related
impairment of homeostatic mechanisms. Evidence from epidemiological and experimental studies
suggests that independent of pharmacokinetic alterations, the elderly are more sensitive to the drugs
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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
having adverse effects on CNS. e.g. elderly are more sensitive to the CNS effects of benzodiazepines i.e.
adverse effects of benzodiazepines occurs at lower drug concentration in elderly than in young.
S.No.
1.
Table A : The physiological changes in elderly
Organ system
Manifestation
Decreased Total body water, lean body mass, serum
Body composition
albumin and increased body fat
2.
Cardiovascular system
3.
Central Nervous System
4.
Gastrointestinal system
5.
Renal system
6.
7.
Liver
Immune system
8.
Pulmonary system
Decreased baroreceptor activity, cardiac output
Decrease in the weight and volume of brain
Alterations in several aspects of cognition.
Increased gastric pH, delayed gastric emptying.
Decreased gastrointestinal flows, and slowed
intestinal transit blood
Decreased Glomerular filtration rate, renal blood
flow, tubular secretory functions, and renal mass
and Increased filtration fraction
Decreased liver size and liver blood flow
Decreased cell mediated immunity
Decreased respiratory muscle strength, total
alveolar surface and vital capacity
Similarly they are sensitive to drugs having anticholinergic properties e.g. Dicyclornine. This is
because ageing causes reduction in the cerebral blood flow, and therefore selective decline in the
cholinergic neurons in some parts of brain occurs leading to cognitive impairment and memory loss.
Mono amino oxidase activity increases with ageing, resulting in decline in noradrenaline and
dopamine levels in brain, associated with increased sensitivity to dopamine blocking agents and
antipsychotic drugs. Elderly demonstrate increased or enhanced response to anticoagulants such as
warfarin, heparin. Reflex tachycardia commonly seen with vasodilator therapy due to dampened
baroreceptor function.
Parameter
Table B : The Pharmacokinetic changes associated with aging
Change
Cause
Effect
ABSORPTION
Rate reduced ;
amount
usually
unchanged
Decreased acid
secretion,
motility, gastric
blood flow,
Delayed gastric
emptying,
slowed
intestinal
transit and
increased
gastric pH
DISTRIBUTION
a) Body
composition
Decreased
muscle mass,
total body
b) Protein
Low serum
Generally no significant effect
because most of drugs are
absorbed by passive diffusion and
no change in bioavailability of most
of drugs.
Decrease active transport Increased bioavailability for some
drugs
Absorption may be affected due
to concomitant use of drugs that
affect GI function (laxative
antacids).
Delayed gastric emptying allows
more contact time in the stomach
for potentially ulcerogenic drugs
such as NSAIDs
Fat soluble drugs: Prolonged half
life and so accumulation occurs and
increased volume of distribution.
Water soluble drugs: High serum
concentrations so decreased
volume of distribution
Protein binding of highly bound
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Examples
of drugs
affected
Diazepam,
lignocairte,
thiopentone,
tricyclic
antidepressants.,
propranolol,
cimetidine, digoxin,
ethanol
Phenytoin,
P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
METABOLISM
EXCRETION
binding
Reduced
albumin
drugs are decreased
Decreased plasma concentration of
highly albumin bound drugs.
Increase in the plasma
concentration of basic drugs
diazepam, NSAIDs,
tolbutamid
c) Protein
binding
Increased
Reduced first
Pass
metabolism
Increased
cdglycoprotein
Decreased liver
blood flow and
liver mass
Greater bioavailability of some dru
Aspirin,
chlorpromazine.
veraparnil,
propranolol
Diazepam.
imiprainme,
fentanyl, phenytoin,
chlordiazepoxide,
theophylline
Reduced
oxidative
(phasel)
metabolism
Reduced
oxidative
microsomal
enzymes
Prolonged elimination half life,
accumulation, arid greater
steady state concentrations of
some drugs
Unchanged
conjugative
(phasell)
metabolism
Reduced
clearance
Preserved
conjugative
enzymes
Drugs which are conjugated are
largely unaffected
Reduced
glomerular
blood flow,
glomerular
filtration rate,
decreased
renal mass and
tubular
secretory
function
Prolonged elimination half life,
accumulation, greater steady state
concentration of some drugs or
their metabolites
Propranolol
Digoxin, lithium,
aminoglycosides,
metformin,
glidenclamide,
vancomycin,
fluoroquinolonses,
etc.
Some drugs such as calcium channel blockers shows both enhanced pharmacodynamic sensitivity
as demonstrated by greater reduction in blood pressure and decreased sensitivity as demonstrated by
reduced atrioventricular nodal blockade occurs simultaneously in elders. So the important rule of thumb
to follow when initiating drug therapy in elderly population is "start low, go slow"(Rohan et al 2004)
POLYPHARMACY
Polypharmacy is wide spread in the population, especially among the elderly. The concomitant
use of several drugs increases the risks of DRP and drug related costs. There is also a clear relation
between falling and the use of higher number of medications. Reducing polypharmacy is not always easy.
Definition
The use of multiple drugs in a single prescription; The use of multiple drugs to treat multiple
concurrent disorders in the same patient; especially the indiscriminate prescription of many drugs to
elderly patients
The term polypharmacy generally refers to the use of multiple medications by a patient. The term
is used when too many forms of medication are used by a patient, when more drugs are prescribed than
is clinically warranted
CAUSES OF POLYPHARMACY
The polypharmacy stems from two distinct sources.
1.
Polypharmacy due to health care providers
2.
Polypharmacy due to patients.
Polypharmacy due to health care providers
Many physicians do not request the patient to compile a complete list of drugs taken (including all
over the counter drugs) or do not review the patients drug list to evaluate medications that could be
stopped. Similarly, symptoms that may be an adverse drug reaction are easily and wrongly attributed to a
new illness, leading to prescription of additional drugs. Drug adverse effects are treated with another
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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
drug in 80% of visits to the physician. The extent of repeat prescriptions is also alarming. They can
represent up to 75% of all items prescribed and their number increases with age, reacting more than
90% for patients aged 85 years and over.
The health care providers are recognized to contribute excessive (or) inappropriate prescribing
practices either directly (or) indirectly through their inability to resist patient's demand for
pharmacological interventions. Clinicians contribute significantly to the problem if they prescribe
medications without considering changes that occur with aging and also failure to assess for adverse
drug events and drug interactions while introducing a new drug.
Polvpharmacy due to patients
Patient's demographics such as female sex, increasing age, rural residence and low education,
increase the risk of polypharmacy. In any age category, 50% of the patients also expect the physicians to
prescribe a drug at each visit because prescription of medication is seen as acknowledging the patient's
ailment. Two other factors frequently encountered in the elderly population are self-medication with OTC
drugs, and borrowing medications from family members and friends and hoarding the medications. The
elderly often believe that they need "Pill for every ill". Over the counter drugs are frequently used and
also the patient does not want to report to his prescribing physician. Elderly patients take over the
counter analgesics more often, for longer periods and in combinations with a greater number of
prescribed medications than younger patients.
FACTORS OF POLYPHARMACY
 Increasing number of chronic illnesses.
 Use of Multiple medications.
 Concept of "a pill for every ill"
 Susceptibility to product advertisements.
 Availability of non-prescription drugs.
 Tendency towards self-treatment.
 Hoarding of older medications.
 Prohibitive cost of prescription products.
 Use of multiple prescribers.
 Use of different sources for medication.
 Lack of knowledge about one's medication and medical conditions (Rollason & Vogt 2003)
CONSEQUENCES OF POLYPHAMACY
The consequences of polypharmacy fall into the following categories.
 Non-adherence or non-compliance.
 Adverse drug reactions.
 Drug - Drug interactions.
 Increased risk of hospitalization
 Inappropriate prescribing
 Increased costs.
Non-adherence (or) non-compliance
The compliance depends upon the process of medication selection, choice of the initial dose, dose
intervals, and the number of drugs prescribed. Several studies suggest that non-adherence increases with
the complexity of drug regimen. Specific non-compliance problems are encountered with the elderly. A
need for elderly to take multiple drugs (use of 4 or more drugs daily) place them at risk of Poor
compliance. The elderly may exhibit non-compliance due to forgetfulness, confusion, impaired physical
function, especially decreased vision and side effects of the medications.
The non-compliance is the main reason for the outpatient treatment failure. Rates of noncompliance have been estimated at 25% to 59% in the elderly. Compliances also decrease when the older
patient does not understand the directions for medication use. The consequence of non-adherence is that
the patient does not receive the full benefit of treatment, and the risk of under (or) over dosage, with an
outcome that can range form a simple inefficacy of treatment to life threatening consequences.
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Adverse drug reactions
Polypharmacy is clearly related to adverse drug reactions. It has been consistently shown thai the
number of ADRs increases with the number of drugs taken. This increase is exponential rather than
linear. It was showed that the intake of more than four medications was correlated with a higher risk of
ADRs. Several hospital inpatient studies report that patients experiencing ADRs take an average of twice
as many drugs as patients with no ADRs.
Older persons with more co-morbidities and lower physical, function scores, use greater numbers
of medications. The presence of multiple disorders, severe disease and altered pharmacokinetics
introduces additional elements contributing to ADRs in elderly patients. The inappropriate prescribing
also contributes the ADRs. Drug Interactions.
Drug-Drug Interactions increases with the number of medications taken. It has even been
suggested that when the number of drugs prescribed to a patient reaches eight, the risk of drug-drug
interaction approaches 100%.
In large groups of geriatric inpatients. the proportion of patients exposed to potential drug-drug
interaction was estimated at 35-60%, even though a clinically significant adverse event was
demonstrated in only 5 -15% of the patients.
Interactions resulting in reduced efficacy of medications may be overlooked more often than
those resulting in a synergistic effect, because other reasons may be used to explain the lack of efficacy
e.g. poor adherence, resistant disease.
A study showed that nearly all the elderly patients were taking two or more drugs and 32% were
taking five or more drugs. Potential drug-drug interactions were registered for 42% and drugs
accounting for the highest percentage of interactions were digoxin, furosemide and antidiabetics, which
were also the drugs most frequently prescribed.
Increased Risk of Hospitalization
The link between polypharmacy and hospitalization seems quite clear when considering that
polypharmacy increases non-adherence, ADR and drug-drug interactions. It was also estimated that
11.4% of hospitalization of the elderly patients in an acute care hospital were due to non adherence,
16.8% due to ADRs etc.
Apart from the above reasons, the drug related falls is one of the main reasons for the
hospitalization among the elderly. Reports of many studies showed that intervention aimed at reducing
polypharmacy among individuals taking 4 or more drugs lead to a greater reduction in the number of
falls.
Inappropriate prescribing (or) inappropriate medication use
Inappropriate use is the prescribing of a medication that has more potential risks than potential
benefit or prescribing that does not f agree with accepted medical standards. Categories of inappropriate
I use includes improper drug selection, use of a drug without indication (including continuing the use of
drug after the indication is no longer) choosing an appropriate drug but the wrong dose (for low or too
high), or any of several other elements of the drug treatment plan.
Inappropriate prescribing for elderly patients are common with studies throughout the world
reporting that 14- 46% of elderly people were prescribed at least one inappropriate medication. It may
cause ADRs leading to poorer health and health care outcomes. The most frequently used inappropriate
medications were long acting benzodiazepines, dipyridamole, propoxyphene, amitriptyline, etc.
Increased Cost
Polypharmacy increases the cost directly via prescription cost and indirectly via the five
consequences such as noncompliance, ADRs, drug interactions, inappropriate prescribing and increased
risk of hospitalization (Corcoran 1997).
DRUG RELATED PROBLEMS
Drug related problems are an essential term in the world of pharmaceutical care. Other terms can
be used for the same concept, such as medication errors, but this term is different from drug related
problems. The errors refer to the mistakes in the process that could lead to problems. Drug related
problems can originate when prescribing, dispensing or taking/administering medicines. Drug use
problems by the patient are probably the most frequent, but are not always noticed. There are several
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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
classifications for drug related problem, but in this article the classification of the Pharmaceutical Care
Network Europe (PCNE) is used to clarify the concepts. Some of the known classifications seem difficult
to be used in practice, and especially the reproducibility of the existing classifications should be
researched further.
The concept of pharmaceutical care started developing in the early 1990s after the milestone
publication of Hepler and Strand on this subject and some years later Hepler depicted pharmaceutical
care as a quality improvement process (a circle of Denning) in which the professional improves the
outcomes of pharmacotherapy. During the quality improvement process, the causes that potentially lead
to problems resulting from pharmacotherapy should be identified and corrected. This philosophy around
optimizing the outcomes of pharmacotherapy and pharmaceutical care lead to the concept of Drug
Related Problems (DRPs), indicating some problem in the pharmacotherapy of the patients. DRPs
therefore are defined as problems in the pharmacotherapy of the individual patient that actually or
potentially interfere with desired health outcomes (definition PCNE 1999). The essential element of this
definition is the impact of the problem on the health-outcome of the pharmacotherapy. If there is no
potential impact, then there is no drug-related problem. It would be much better to prevent drug related
problems than to correct them, but this is not always possible because of the complexity of
pharmacotherapy, lack of training and knowledge of health care providers and the behaviour of the
medicine users. Also, some pharmacotherapy problems are the result of an unexpected reaction of the
individual, like allergies, and cannot always be predicted. Therefore, even if one could analyse the
medication and patient related factors during a medication review before a medicine is handed over to
the patient, the evaluation of the pharmacotherapy after it has been initiated still remains necessary to
detect DRPs and optimise outcomes. A drug related problem is essentially different from a medication
error. According to the NCC MERP a medication error is 'any preventable event that may cause or lead to
inappropriate medication use or patient harm while medication is in the control of a health care
professional, patient, or consumer. A medication error is much more process orientated than outcome
orientated. If something goes wrong in me prescribing or dispensing process, then it is automatically
regarded as a medication error whether or not there is an impact on patient outcome. Additionally, errors
in medication use by patients seem not to be included but such errors can be causes for drug related
problems.
Classification of Polypharmacy
Terminology
The term 'Drug Related Problem' is not unique for a problem with pharmacotherapy. Other terms
have been proposed. For instance 'drug-therapy problem' is often used too, and was introduced by the
group of Cipolle, Morley and Strand. Krska introduced the term 'Pharmaceutical Care Issue' in 2002. That
term is sometimes used in the UK. Fernandez-Llimos et al. recently proposed 'pharmacotherapy failure',
corresponding to negative clinical outcomes resulting from the use or the lack of use of medicines. Those
pharmacotherapy failures then include necessity, effectiveness and safety problems. All these terms may
stand for similar concepts as drug-related problems and therefore it remains important to define the
concept properly before using it in research or publications.
How and where do DRPs originate
In the entire course of installing pharmacotherapy there are three main processes where a drug-related
problem can be generated: the prescribing, dispensing and drug use process as illustrated in Fig. 1
DRPs can also be split into real and potential DRPs. Additionally some of those problems cannot
be avoided without reducing the effect of the pharmacotherapy, e.g. nausea as a side effect of oncolytic
medicines, or interactions between different medications for AIDS.
Prescribing problems originate usually behind the physicians' desk, or sometimes at the bedside.
Usually negligence or lack of knowledge may cause such problems, sometimes lack of information
regarding the full therapeutic profile of the patient, and at times possibly also missing laboratory data.
The physician can also be influenced by external entities, such as the pharmaceutical industry, and may
not prescribe the most appropriate medicine. Nurses may also cause DRPs by wrongly copying the
physicians' instructions on a chart or order form, or by not providing medication as intended.
Dispensing problems also are often a result of negligence. Misinterpreting the physicians"
handwriting, not performing a drug use review, taking the wrong box or bottle may all cause DRPs, Drug
use problems by the patient probably occur very frequently, but are not always noticed. In general, half of
the patients do not adhere to the pharmacotherapy. This leads to a significant amount of drug related
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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
problems, but only part of those problems are detected e.g. when the patient is taken to the emergency
department of a hospital for not taking insulin.
List of DRP classifications
 ABC system
 ASHP classification
 Cipolle et al.
 Granada consensus
 Hanlon
 Hepler/Strand
 Krska et al.
 Mackie PAS
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 PCNE Classification Pi-doc SHB-SEP Westerlund classification
There are eight criteria that should be considered in the selection of drug related problem
classification and those criteria in the mean time also constitute criteria for validation.
Appropriateness: is the classification content appropriate to the questions which the application
seeks to address?
Acceptability: is the classification acceptable to pharmacists and researchers?
Feasibility: is the classification easy to use and process?
Interpretability: how interpretable are the codes of the classification?
Precision: how precise are the codes of the classification?
Reliability: does the classification produce results that are reproducible and internally consistent?
Validity: does the classification document what it claims to measure?
Responsiveness: does the classification offer options to follow interventions and outcomes of
interventions? These criteria are not uniformly described in the literature; nor can they be prioritised in
terms of importance, rather they should be considered in relation to the proposed application of a DRP
classification.
The concept of drug related problems is essential for pharmaceutical care, and the pharmaceutical care
process. Nevertheless, documenting DRPs systematically in practice or for research is difficult. There are
a number of instruments available. But the available validation data for some instruments show poor
reproducibility. There seems to be a difference in how different professionals assess the drug treatment
process, and identify the problems. This difference in skills is enhanced by varying levels of actual
knowledge. Documentation systems for other professions also pose problems in practice. The quality and
correlates of medical records in the ambulatory care setting are debatable too. It is certain that actual and
potential drug related problems occur, and can be corrected in order to improve the outcome of
pharmacotherapy. But there seems to be little agreement on how to name and classify these problems
between both researchers and practitioners alike (Foppe van, 2005).
RISK MEASURES
RELATIVE RISK :
Ratio of risk of an outcome such as disease in one group (say, the exposed group) to that in any
other group (generally the control group – the unexposed group) is called the relative risk (or risk ratio).
FORMULA:
RELATIVE RISK =Incidence rate of the disease in exposed group Incidence rate of
the disease in unexposed group
INTERPRETATION:
RR =1 implies that the two groups have same risk. Thus, significance here implies that RR is
different from one. RR >1 has the usual meaning of increased risk but RR <1 could mean that there is a
protective effect.
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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
ODDS RATIO:
Odds ratio defined as odds in the diseased cases to odds in the non diseased subjects.
FORMULA:
ODDS RATIO= Odds in the diseased cases
Odds in non diseased subjects
INTERPRETATION:
•
•
If OR > 1, there is a positive association
If OR < 1, there is a negative association
ATTRIBUTABLE RISK:
The difference between the risk in exposed subjects and unexposed subjects is called attributable
risk.
FORMULA:
Attributable Risk= Incidence rate of the disease in the exposed group − Incidence rate of the
disease in the unexposed group
NUMBER NEEDED TO TREAT:
Number needed to treat (NNT) is the reciprocal of the absolute risk reduction.
FORMULA:
NNT is the inverse of the absolute risk reduction – the difference between the proportion or rate of
events in the active treatment intervention group (Pa) and the proportion of events in the control group
(Pc).
NNT =1/ (Pa-Pc)
INTERPRETATION:
The ideal NNT would be 1, where all the patients in the treatment group have improved, but no-
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one has in the control arm. In theory, the higher the NNT, the less effective is treatment, because more
people need to receive the treatment to see a benefit in one. However, the value of an NNT should be
interpreted in light of the clinical contact.
AIMS AND OBJECTIVES
Aim: The aim of this study was to analyze the Drug related problems and usage of drugs among geriatric
patients living at old age homes.
Specific objectives:
1. To assess the drug related problems in geriatrics with polypharmacy.
2. To provide pharmaceutical care interventions based on the existing drps.
3. To measure the risks associated for the development of drps in geriatrics.
4. To improve the medication adherence by appropriate patient counseling.
5. to assess the drug usage pattern among geriatric patients.
METHODOLOGY
Study sites:
Oldage homes in and around Anantapur district:
 St.Vincent de’ Paul- home for the aged (ATP)
 Sahara oldage home (ATP)
 Vrudhajanodharana ashram (ATP)
 Vasavi oldage home (ATP)
 Vasavi oldage home (TDP)
 Prashanthi Nilayam (HDP)
 Sri Krishna oldage home (TDP)
 Amma vodi oldage home (ATP)
 Jhansi lakshmi bai oldage home (TDP)
Study design: This was a prospective study conducted in oldage homes, in and around Anantapur
district.
Study period: The study was conducted over a period of 6 months from September to February.
Study criteria:
Inclusion criteria
 Patients of either sex, aged more than 55 years.
 Patients who are on prescription medications for chronic diseases.
 Patients who give consent to participate in the study.
Exclusion criteria
 Patients who are taking other system of medications (Ayurvedic, Homeopathic medications).
 Patients who are not able to give information (Hearing/cognitive impairment).
 Patients who are not willing to or unable to give consent to participate in the study.
Sources of data:
All necessary data was collected from the following sources:
* Patient’s interview
* Patient’s prescription
* Patient’s own medical records/dairy
* Patient’s care takers interview
Study procedure:
 Suitable data collection form was designed for the study. The data collection form includes
various details of patients like demographic, disease and treatment related information.
 Patients satisfying the inclusion criteria were enrolled from the study sites.
 Pharmacist upon visit to old age homes interviewed the patients and reviewed all the
medications used by the patients and this information was documented in the data collection
form.
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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
 The study pharmacist reviewed the data collection form to determine the presence of drug
related problems (such as drug interactions, adverse drug reactions, over dosing, under
dosing, untreated indication, drug used without indication, failure to receive drug, nonadherence, improper selection of drugs).
 The study pharmacist also collected details of current prescribed medications for each
patient. This was done to quantify the occurrence of polypharmacy.
 Upon patient interview if there will be any medication non-adherence, they will be counseled
to improve the adherence.
 Various risk factors like age >65, polypharmacy (>3drugs), co-morbidities, severity of disease
& economic status associated for the development of DRPs will be assessed by using 2X2
contingency table.
Characteristics
GENDER
Male
Female
AGE
65-74 years
75-84 years
85 and above
MEAN AGE ± S.D
SMOKERS
ALCHOLICS
No: of patients(%) or mean ± S.D
89(59.33%)
61(41.67%)
54(36%)
77(51.33%)
19(12.67%)
50±29.206
50(33.33%)
56(37.33%)
Table 1 shows that males (59.33%) are more affected with chronic diseases than
females(41.67%).most of the patients fall between the age group 75-84 years (77(51.33%)) and mean
of the ages was found to be 50±29.206.Most of the patients were alcoholics (37.33%)than
smokers(33.33%) in their social habits
Table: 2 MAJOR DIAGNOSIS (n=150)
No: of
Diagnosis
patients(%)
Diabetes mellitus 49 ( 32.66% )
Hypertension
26(17.34%)
LRTI
15(10%)
COPD
2(1.33%)
IHD
10(6.67%)
CCF
2(1.33%)
PT
3(2%)
Liver Cirrhosis
9(6%)
Anemia
15(10%)
Asthma
19(12.67%)
Total
150
Table: 2 shows that most of the patients were suffering with diabetes mellitus(32.66%) and
hypertension (17.34%).
Table: 3 COMORBID CONDITIONS
Co morbid
Percentage
conditions
No: of patients (%)
Diabetes mellitus
32
21.33%
Pneumonia
11
7.33%
IHD
14
9.33%
Seizures
7
4.66%
UTI
12
8%
Stroke
3
2%
CHF
3
2%
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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
Diabetic Nephropathy
Renal failure
Anemia
COPD
LRTI
TB
7
1
12
5
10
10
4.66%
0.66%
9%
3.33%
6.66%
6.66%
Pericardial effusion
10
6.66%
Parkinsonism
1
0.66%
Dyslipedimia
7
4.66%
Table: 4 DRUGS DISTRIBUTION IN GERIATRICS
Percentage
Drug class
No: of patients (%)
Antihypertensive
26
10%
Anti anginals
17
6.53%
Lipid lowering agents
11
4.23%
8
23
3.07%
8.84%
81
31.15%
Anti ulcers
12
4.61%
Anti asthmatics
19
5.27%
NSAID s
19
5.27%
Anticonvulsants
7
2.69%
Anti thrombotic
5
1.92%
Antidepressants
2
0.76%
Antiemetic
9
3.46%
Anti tubercular
10
3.84%
Coronary vasodilators
11 =260
4.23%
Anxiolytics, Sedatives
Anti bacterial
Oral hypoglycemic agents
and insulin
From table 3 it shows that most of the patients have diabetes mellitus as co morbid condition
(21.33%) irrespective of their chronic condition. Table 4 shows that oral
hypoglycemic(31.15%)are more frequently used than other medications followed by
antibacterial(8.84%).
Table:5 INTERVENTIONS MADE FOR DRP’S
No: of
Primary domain No: of DRP’S Interventions
Drug overuse
Inappropriate
drug
54
52(96.29%)
20
20(100%)
Drug duplication
34
19(12.66%)
No clear indication 32
31(96.87%)
Drug underuse
18
18(100%)
ADR
13
13(100%)
DI
62
57(91.93%)
Total
233
210
Table 5 shows that most of the patients faced drug related problems due to drug interactions(62)
followed by drug overdose(54).Most of the interventions for inappropriate drug, contraindication,
adverse drug reactions were rectified and improved(100%) followed by other problems.
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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
Table:6 FREQUENCY OF DRP’S WITH VARIOUS DRUG CLASS
Drug
Adverse
overus Inappropriate Inappropriate
No clear
Drug under Drug
ed
drug
duplication
Indication use
reactions
Drug
Total (Drug
Interact related
ion
problems)
Anti
hypertensive
Anti diabetics
Anti asthmatics
Anxiolytics
Anti thrombotics
Antibiotics
NSAIDS
Anti lipidemics
Anti inflammatory
Anti emetics
19
6
12
11
3
2
12
53
12
1
2
1
7
12
-
6
3
-1
3
1
-
2
5
--5
6
4
-
1
1
7
-1
11
12
-
4
1
2
2
3
-2
1
--
-2
-3
4
2
----
8
10
12
11
---9
--
33
23
23
18
15
10
24
34
0
Total
54
20
34
32
18
13
62
233
Drug classes
Table: 7 COMPARISON OF MEDICATION ADHERENCE BEFORE AND AFTER INTERVENTION
Group
Low
Medium
Chi square
adherence
High
adherenc
e
adherence
BEFORE
64
76
10
29.129
AFTER
42
62
46
P-value
P<0.0001
Level of
significanc
e
Highly
Significant
DRP’S WITH VARIOUS CLASSES OF DRUGS
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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
1. ANTI HYPERTENSIVES
2. ANTI DIABETIC
3. ANTIASTHMATIC
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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
4. ANXIOLYTICS
5. ANTITHROMBOTICS
6. ANTIBIOTICS
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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
7. NSAID’S
8. ANTILIPEDIMICS
9. ANTI-INFLAMMATORY
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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
RISK FACTOR ASSESSMENT IN DIFFERENT GROUPS
Age wise risk assessment
Age>65
Age<65
DRP’P
52
28
NO DRP’S
28
42
The one-sided P value is 0.0019, considered very significant. The row/column association is statistically
significant.
POLYPHARMACY
DRP’S
>3
<3
No DRP’S
55
23
25
47
Calculation details:
Chi-square statistic (with Yates correction) = 8.397 Degrees of freedom
=1
Relative Risk
Relative risk = 1.625
95% Confidence Interval: 1.169 to 2.258 (using the
approximation of Katz.)
The one-sided P value is < 0.0001, considered extremely significant. The row/column association
is statistically significant.
Chi-square statistic (with Yates correction) = 17.858
Relative Risk
Relative risk = 2.092
95% Confidence Interval: 1.451 to 3.017
DISEASE SEVERITY
DRP’S
No DRP’S
35
24
SINGLE DISEASE
24
47
MULTIPLE DISEASE
The one-sided P value is 0.0031, considered very significant. The row/column association is statistically
significant.
Chi-square statistic (with Yates correction) = 7.468.
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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
Relative Risk
Relative risk = 1.755
95% Confidence Interval: 1.190 to 2.587336
SOCIOECONOMIC STATUS
INCOME
DRP’S
No DRP’S
>3000
65
15
<3000
59
11
The one-sided P value is 0.3921, considered not significant. The row/column association is not
statistically significant. Chi-square statistic (with Yates correction) = 0.07498.
Relative Risk
Relative risk = 0.9640
95% Confidence Interval: 0.8330 to 1.116
DISCUSSION
From the above study , 1 shows that males (59.33%) are more affected with chronic diseases than
females(41.67%).Most of the patients fall between the age group 75-84 years (77(51.33%)) and mean of
the ages was found to be 50±29.206.Most of the patients were alcoholics (37.33%)than
smokers(33.33%) in their social habits.
Most of the patients were suffering with diabetes mellitus (32.66%) and hypertension (17.34%)
followed by other diseased conditions.
From table 3 it has shown that diabetes mellitus (21.33%) is prevalent as co morbid condition
followed by ischemic heart disease(9.33%).
Table 4 shows that oral hypoglycemic (31.15%) are more frequently used than other medications
followed by antibacterial (8.84%).So, it suggests that diabetes mellitus is the most common chronic
condition to be treated in this geographical area irrespective of all sociodemographic characteristics.
Interventions are made to the patients with polypharmacy to treat drug related problems which
were depicted in the above table 5.It shows that most of the patients faced drug related problems due to
drug interactions (62) followed by drug overdose(54).Most of the interventions for inappropriate
drug,contraindication,adverse drug reactions were rectified and improved(100%) followed by other
problems. Frequencies of DRP’s are with various drug classes are depicted in the table 6 has shown that
antihypertensive have maximum DRP’S(53) followed by anti-inflammatory(34).in that maximum
problems were drug interactions(62) followed by drug overdose (54) and inappropriate duplication. The
frequencies of each category of drugs are depicted as graphs above.
After pharmacist interventions, that is patient counseling most of the DRP’s are overcome and the
adherence of the patients were increased to the treatment after the intervention. A statistical chi square
test was done to identify the level of significance before and after the interventions. Chisquare value was
found to be 29.129 and Pvalue<0.0001.So,there exists a significant association between patient
counseling and level of adherence.
Risk ratio assessment of various risk factors like age, polypharmacy, disease severity and income
status were assessed in the above results.
Age factor, Polypharmacy, Disease severity had significant association between the risk factors of
Drug related problems as their p value<0.0001 and there is no statistically significance between the
income status and DRP’S on the adherence where its p value was found to be p>0.05 respectively. Overall
study shows that drug related problems are more seen from this study and can be improved by
pharmacist mediated intervention.
CONCLUSION
An increase in the number of medications may pose higher risk of polypharmacy because the
elderly population has higher prevalence of chronic diseases, multiple drug use is very common. The fact
that the elderly take more medications for the treatment of several diseases makes them more
susceptible to the occurrence of adverse reactions. In this study drug overuse and drug interactions were
common in older people taking five or more medications. Drug overuse is most frequent drug related
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P. Samarasimha Reddy & Md. Waseemuddin., Asian Journal of Pharmaceutical Technology & Innovation, 02 (09); 2014; 39-58
problem in patients taking many medications, but drug interactions are also common. . In this sample,
patients reported very high medication adherence rates regardless of number of medicines they
administered. Among patients on multiple medicines, most patients with suboptimal adherence were
perfectly adherent to all. Age, polypharmacy, severity of disease has a significant association with the risk
measures ( Relative risk, Attributable risk, Odds ratio, Number needed to treat ).
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