FACULTY
OF
M EDIC INE – U NIVERSITY
OF
P ORTO
Department of Biostatistics and Medical Informatics
Introdução à Medicina 2005/2006
Drug Allergy Prevalence in the Adult Population
Flores Santos LAQ,
Pinho da Costa JL,
Maia LA,
Brosseron L,
laqfs@med.up.pt
med05009@med.up.pt
med05017@med.up.pt
med05014@med.up.pt
Gomes JM,
Ferreira S,
Coelho L,
Sá JA,
med05011@med.up.pt
med05091@med.up.pt
med05013@med.up.pt
med05008@med.up.pt
Marques JP,
Magalhães J,
med05010@med.up.pt
med05003@med.up.pt
Adviser: Azevedo LF, lazevedo@med.up.pt, Class: 13
Abstract
Introduction: Although drug allergy is a common and complicated problem in clinical practice, its
diagnosis is normally difficult. It is the most common iatrogenic illness, complicating 5 to 15 % of
therapeutic drug courses. In the USA, more than 100,000 deaths are attributed annually to serious
adverse drug reactions. 3 to 6 % of all hospital admissions are because of adverse drug reactions.
Aim: Determine the lifetime prevalence of drug allergy in the general adult population. Identify the drugs
more frequently associated to it and establish some associations between drug allergies and other type of
allergies diseases.
Participants and Methods: Cross-sectional and descriptive study in which the target population
consisted of individuals, 18 years old or older, residents in Porto and with household telephone . 204
phone questionnaires were applied, using Two Stages Random Digit Dialling as a method for random
sampling. A descriptive analysis was made. For all the statistical tests we used a confidence level of
95%. The program SPSS® was used to analyse data.
Results: The sample self-reported lifetime prevalence of adverse drug reactions was of 19.7% (30/152)
with a confidence interval from 13 to 26%. 11.2% (17/151) with a confidence interval from 6% to 16% of
the inquired had had drug allergies confirmed by a doctor. In our sample, 17.6% (25/142), with a
confidence interval from 11 to 24%, of the people thought that they were allergic to drugs. We found no
association between reported adverse drug reactions and allergic diseases (Qui-square test, p=0.614),
but between drug allergies confirmed by a doctor and allergic diseases there is a statistical evidence of
an association (Qui-square test, p=0.005). Antiinfectious drugs, such as penicillin, were the drugs
reported to be responsible for most self-reported adverse drug reactions and drug allergies.
Discussion: We were able to conclude that though 19.7% inquired had had problems after taking drugs,
at least once in their lives and only 36.7% had this reaction confirmed by a doctor as an allergic
reaction. These prevalences are high, but if it is considered that only 25% of adverse drug reactions are
drug allergy, the values are closer to ones in other studies. We also concluded that antiinfectious drugs,
such as penicillin, were the drugs reported to be the responsible for most self-reported drug allergies.
Key-words: Drug Hypersensitivity, Prevalence, Telephone, Interviews, Cross-Sectional
Studies, Statistics.
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
Introduction
Adverse reactions to drugs include all non therapeutic consequences of the drug with
the exception of treatment failures, intentional or accidental poisoning, and drug
abuse.[1] The terms "drug allergy“, "drug hypersensitivity" and "drug reaction" are
often used interchangeably. Drug reactions encompass all adverse events related to drug
administration, regardless of etiology; drug hypersensitivity is defined as an immunemediated response to a drug agent in a sensitized patient; drug allergy is restricted
specifically to a reaction mediated by IgE [2]. Drug hypersensitivity reactions are
thought to represent 25% of adverse drug reactions [1].
In the perspective of our study, and due to our incapacity to distinguish by means of our
data collection methods drug allergy and drug hypersensitivity, we decided to use the
term "drug allergy" in both cases.
Almost 80% of adverse drug reactions are predictable reactions (type A). Some
examples of type A reactions are toxicity, side effects and drugs interaction. Type B
reactions are not predictable, are dose independent, are not related with the
pharmacologic actions of the drug and are extremely important because they can cause
serious diseases and even death. Allergic reactions, pseudo-allergic reactions and
idiosyncratic reactions are examples of type B reaction. [3]
Although drug allergy is a common and complicated problem in clinical practice, its
diagnosis is normally difficult, due to the variability of the clinical picture, to the
insufficient
understanding of
the
pathophysiologic
reactions
of
most
drug
hypersensivities and to some weakness of the classification of allergic reactions in four
types according to Gell and Coombs, which is helpful for some drug-allergic reactions
but fails to explain the most common (exanthema).[4,5]
Reactions may be immediate (as in anaphylaxis, bronchospasm, urticaria, or
angio-oedema); accelerated (occurring within 3 days (as in urticaria, asthma); or late
(occurring >3 days after first receiving the drug). Late reactions include mucocutaneous
syndromes
(rashes, exfoliative dermatitis) or haematological type (anaemia,
thrombocytopenia, neutropenia). [5]
Epidemiological studies about the prevalence of adverse drug reactions have been
focussed mainly on hospitalized patients and in hospital admissions. It has been
estimated that 3 to 6% of all hospitalized admissions are because of adverse drug
reactions and that 6 to 15 % of hospitalized patients in USA experience a serious
adverse drug reaction, placing the consequences of drug hypersensitivity between the
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
4th and 6th leading cause of death of hospitalized patients in the USA. [3,5] In this
country, more than 100,000 deaths are attributed annually to serious adverse drug
reactions. They are also the most common iatrogenic illness, complicating 5 to 15 % of
therapeutic drug courses. [2]
The main drugs implicated are antibiotics and non-steroidal anti-inflammatory drugs
(ampicillin, amoxicillin, trimethoprim-sulfamethoxazole and penicillin are the most
observed causes of adverse drug reactions). [3,1]
Aim
The aim of this study is to determine the prevalence of drug allergy in the adult
population of Porto and also to identify the drugs that are more frequently associated to
allergic reactions, to describe the different types of allergic expression and to relate the
allergic reactions already described with the presence of some diseases.
Participants and Methods
Study Design
This study is a cross-sectional (observational and retrospective) descriptive study, via
telephone, where we are able to determine prevalence.
Study Participants
The target population of our study is the adult population (18 years old or above)
resident in the Porto region that has a telephone in their household. The unit of analysis
is, therefore, the person.
Sampling Methods
The sampling methods that were used are the Two Stages RDD Sampling methods, one
of the subdivisions of the “Random digit dialling” (RDD) methods, that was invented
by Mitofsky in 1970 and was developed by Waksberg. [6]
The first stage of these methods is the random choice of seven digit prefixes, which in
our case are able to include the telephone numbers of the Porto region, thus, defining a
group with the same general characteristics. Similarly, at the second stage, two figure
suffixes are chosen in a random form. In this way, it is possible to obtain the nine digit
numbers in which the telephone numbers consist.
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
The objective is to form a cluster of combinations between the list of prefixes and the
list of suffixes. These clusters are useful in obtaining five residential numbers at the
most, having used the same prefix.
Having obtained a number, we then proceeded to the dialling of the number. If the
number was not recognized, it was instantly deleted, and then we passed on to the next
prefix. If the number was indeed recognized we had to establish that the number really
did belong to a residence. All other possibilities were excluded beforehand, such as
commercial institutions, companies, offices, faxes and others, and if the number
corresponded to one of these pre-excluded categories it was also eliminated.
If the number was a residential one, we then dialled a number with the same prefix, but
with a different suffix, until a total of five residential numbers were obtained. If the call
was not answered, the number was redialled for the following two days at different
times of the day, and if it was not answered then, the number was deleted, and we
proceeded as if it was a non-residential number. Refusals to answering the questionnaire
were included as residential numbers, thus taking part in the five residential number
clusters. The advantage of this method is that, having a prefix corresponding to a
residence, there is a large probability that this prefix corresponds to a number of
residences in a certain residential area. (See Figure 1)
The main advantage of this method in comparison to that of the phone list is that the
phone list does not have all existing phone numbers in it, but only the registered ones.
However, there are some disadvantages, such as the fact of having to find out if the
phone number belongs to a residence or even if the number is actually available.
Another disadvantage is the existence of more than one phone in the same household,
contributing to an imprecision within the sampling.
Data Collection Methods
The questionnaire was supposed to be made to the person that will be the next to
celebrate his/her birthday and that belongs to the target population, thus, lowering the
possibility of imprecision of the sample and making it as random as possible. This is
because the population that answers the phone or is in the household at the time is
obviously different to in comparison to the target population. However, it was verified,
in the pilot stage, that the answer rate was extremely low, due to factors like
unavailability of the required person or refusal to call him/her, which would imply a
huge amount of phone calls and an exaggerated quantity of time spent.
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
In order to solve this problem the questionnaire was firstly made to the person who
answered the phone call, asking afterwards if there was the possibility to interview the
next person to celebrate his/her birthday. If the next person to celebrate his/her birthday
was available, the first questionnaire was eliminated, and if not it was accepted.
This option was taken after recognizing that the interviewed persons were gentler and
more receptive in the end of the interview, therefore with an increased predisposition to
call the next person to celebrate his/her birthday and convince that person to answer the
questionnaire.
This method, on one hand, increased significantly the answer rate, but on the other hand
diminished the randomization of the sample, which may have led to some bias.
The only exclusion criteria used for the application of the questionnaire were the
non-belonging to our target population and the incapacity of answering it properly, due
to deafness or other physical or psychological incapacity. All the remaining persons
were included.
The questionnaire used to obtain the necessary data was an adapted questionnaire,
provided by our adviser, in which it was possible to answer all the objectives we had
proposed to. (See Attachment 1: Questionnaire). This questionnaire is not a validated
one, but it was tested on the pilot stage and all the necessary modifications and
adaptations were then introduced.
Trying to understand the difficulties which accompany the questionnaire and in order to
promote the familiarization of the instrument, we conducted a preparatory test, in the 1st
of March.
The telephone interviews were done between the 2nd of March and the 26th of April of
2006 at the SBIM offices.
Variables Description:
The analysed and studied main variables were the following: the existence of an adverse
drug reaction at least once in life, the drug that caused the reaction, the type of reaction
to the drug, the time that it took for the reaction to begin and how long it went on for,
the need for any medical appointment and the exams that confirmed the presence of a
specific reaction, the presence of allergic illnesses or allergies to any other substances,
the age of the person and the sex of the person.
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
Figure 1: Flowchart of Two Stages Random Digit Dialling Method.
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
Statistical Analysis
We classified the drugs in families like the classification used in the INFARMED
database. This pharmacological/therapeutic classification system of “Prontuário
Terapêutico” corresponds to the Anatomical Therapeutic Chemical (ATC) classification
system, recommended by the World Health Organization. The purpose of the ATC
system is to serve as a tool for drug utilization research in order to improve quality of
drug use and to allow trends in drug consumption to be studied without the
complication of frequent changes to the system at an international level. One component
of this is the presentation and comparison of drug consumption statistics at international
and other levels. In the Anatomical Therapeutic Chemical (ATC) classification system,
the drugs are divided into different groups according to the organ or system on which
they act and their chemical, pharmacological and therapeutic properties. Drugs are
classified in groups at five different levels. The drugs are divided into fourteen main
groups (1st level), with one pharmacological/therapeutic subgroup (2nd level). The 3rd
and 4th levels are chemical/pharmacological/therapeutic subgroups and the 5th level is
the chemical substance.[7]
We made a descriptive analysis for all the variables. To determine prevalence
proportions graphs and tables were used. We used the non-parametric Qui-square or
Fisher’s tests to find associations between the main nominal variables. The Wald
method was used to determine an approximated confidence interval for the most
important proportions in our study. For all the statistical tests we used a significance
level of 5% (=0,05), thus a confidence level of 95%.
The gathered data was organized and analysed using an electronic data base, via the use
of the software SPSS® 13.0 for MS Windows®.
Results
Data collection
All phone calls were made between the 2nd March and 26th April and the time-table
included the period between 9 a.m. and 6.30 pm.
A total of 1750 phone calls were made, 51% of which were phone numbers that were
not available, 12% corresponded to households, 22% were commercial establishments
and 15% were non answered phone calls, faxes, or other non-households numbers.
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
Having contacted 204 households, we were able to obtain 152 answered questionnaires.
Therefore, our answer rate (between the number of answered questionnaires and the
number of contacted households) was 75%.
Amongst the inquired that were asked about if they were the next to celebrate birthday,
only 40% answered negatively.
Characterization of sample
The sample obtained consists of 152 adults (18 years old or older) resident in the Porto
region, that have a phone in their household, and that were able to answer to the
questionnaire in an appropriate form. Of the 152 people, 89 were of the feminine sex
(59%), 50 (33%) were of the masculine sex and 13 (8%) did not answer this question.
As the variable “age” does not have a normal distribution in our sample, the median of
this variable was calculated and it is 54.
Figure 2 shows the distribution of the people that participated in the study. Although the
variable age is continuous, we transformed it into a categorical one by grouping people
into age groups of a range of twenty years.
Figure 2: Distribution of people that participated in the study, using age groups of a range of ten years.
Numbers inside bars and the bars represent absolute frequencies.
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Answers of the inquired
Of the total number of people that answered our questionnaire (152), 19.7% reported
they had an adverse drugs reaction, at least once in their lives, and 11.2% had had an
allergy confirmed by a doctor. In those who reported adverse reactions, 36.7% had this
reaction confirmed by a doctor as an allergy reaction to a drug.
Figure 3 shows the distribution of people that had presented adverse reactions to drugs
and its confirmation by a doctor.
Figure 3: Percentage of people that had felt sicker or had had any problems after having taken a drug and
confirmations by a doctor. Numbers in graph represent the absolute frequencies and the area of the
sections is proportional to the relative frequency (%) of each category.
We concluded that there is an association between the group that have felt sick due to
drug’s intake and the group that have medical confirmation of drug allergy (p<0.000).
In addiction to this, we presented on Figure 4 the distribution of the people that reported
adverse drug reactions according to their age groups. The Chi-Square Test indicated no
statistical association between the occurrence of allergy and the different age groups
(p=0.708).
One of our secondary objectives was to identify the drugs that are most frequently
associated to adverse reactions. We concluded that the drugs that were most frequently
associated to these reactions were mainly the antiinfectious drugs, such as Penicillin.
We observed that 16.5% of the inquired people think that is allergic to at least one drug
(95% confidence interval: 11% - 24%). Using a qui-square test, we also found out that
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
there is an association between the group that have felt sick due to drug’s intake and the
group that thinks they have allergy to drugs, (p<0.000).
Adverse drug reactions by age group
100%
Proportion in age group
85%
80%
Felt sicker throughout
his/her life after taking
a drug?
83%
79%
76%
No
60%
40
41
34
Yes
5
40%
24%
20%
21%
15%
7
13
9
17%
1
0%
From 18 to
39 years
From 40 to
59 years
From 60 to
79 years
80 years
or more
Age groups
Figure 4: Distribution of the people that reported adverse drug reactions according to their age groups.
Numbers inside bars are the absolute frequencies; numbers above the bars and the area of the bars are
proportional to the relative frequency of yes/no for each age group.
It is important to point out that 16.4% of the inquired did some test or analysis to
confirm drug allergy and that 23.3% of the people who experienced adverse drug
reactions did some test or analysis.
17.8% of the inquired people reported that they had an allergic disease. We can see on
Figure 5 the most common allergic diseases reported. However we were not able to
establish an association between the occurrence of allergic disease and people who
experienced adverse drug reactions (p=0.614). Nevertheless, between drug allergies
confirmed by a doctor and allergic diseases there is a statistical evidence of an
association (Qui-square test, p=0.005). 21.7% of the inquired people stated they had
other kinds of allergy such as allergy to pollen, food, dust, animals.
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
50%
40%
Proportion
40%
30%
30%
20%
25%
8
6
5
10%
5%
1
0%
rhinitis
asthma
other
urticaria
Figure 5: Most common allergic diseases reported. Numbers inside bars are the absolute frequencies;
numbers above the bars and the area of the bars are proportional to the relative frequencies.
The majority of the people that reported adverse drug reactions had problems with one
or two drugs (24 people – 92.3%).
The most common allergy symptoms were associated with the skin (20 people, 53% of
those who answered which type of adverse reaction they had). 7 people (18%) reported
having had a digestive reaction and 4 (11%) stated having had a respiratory reaction. 7
people (18%) had other types of reactions like dizziness or agitation.
67% of those who experienced adverse drug reactions stated that they looked for
medical assistance and 30% stated they needed medical treatment.
Finally we show on Figure 6 some values that allow us to have an idea of the
distribution of the adverse drug reactions and drug allergies in the adult population of
the region of Porto.
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
Adverse drug reactions
Drug allergy
95% confidence interval: 13%-26%
95% confidence interval: 6% - 16%
Think is allergic to some drugs
95% confidence interval: 11% - 24%
Figure 6: Prevalence of adverse drug reactions and drug allergies in the adult population of Porto.
Discussion
Questionnaire application limitations
At the “pilot stage” we verified that the questionnaire introduction was not adequate,
due to both its extension and the complexity of phrasal structure and lexicon used. In
order to overcome these limitations, we tried to adjust the introduction to an oral
register and also turn it briefer.
We had some problems with the inquired population. This can be explained by different
reasons which we dealt with, such as: understanding difficulties about the phone call
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objective and also about the applied questions, brought by the advanced age of many of
those who were inquired; individuals who belong to a younger stratus, mainly active
class, shown reticent to participate in the study, alleging they did not have time to spare,
and gave no possibilities to further contact.
It is worthy of note that the time-table available to realize the phone calls did not
include the totality of day periods – phone calls were made during the morning and the
afternoon – leading to a certain bias. The active population presumably working at the
time was nearly excluded.
Moreover, we dealt with huge difficulties to contact people in their domiciles due to
several factors such as: often, the person who answered the phone did not live in that
residence (for example: the housekeeper ) and wasn’t able to give us the information
about the possibility of future contact with the residents; at the pilot stage we tried to
interview the full-aged resident that was next going to celebrate birthday, so as to
effectuate a participants random choice, but this method dramatically increased our
difficulties and made the contact with the required person frequently impossible.
Consequently, we proceeded with some changes in the participants’ selection method:
first we interviewed the individual who answered the phone if this one was resident and
adult, and then, at the end of the questionnaire, we asked if it was possible to speak with
the adult person which would be the next to celebrate birthday. If the answer was
affirmative, the first interview was then cancelled and the last one considered in the
matter of the study. This procedure, although indispensable in order to fulfil our
deadlines, led certainly to a bias that must be present while discussing the results.
However, after having done the Fisher’s Exact Test we concluded that there was no
association between being (or not) the next to celebrate birthday and the group that had
experienced an adverse drug reaction (p=0.664).
Random Digit Dialling disadvantages
The prefix and suffix random selection, which meant to reduce the sample slanting, led
however to a large amount of calls to non-attributed phone numbers, which obliged us
to make innumerable unfruitful phone calls in order to attain the necessary domiciles.
This fact contributed to the waste of our disposable time, already very limited.
Besides, even if the first combination of one prefix with one suffix was a domicile (and
so a valid number), the following ones weren’t so, many being commercial or non-
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
attributed. Not so infrequently we had to do dozens of phone calls with the same prefix
in order to get the necessary five domiciles. This led to a very low household rate.
Statistical analysis
We were able to conclude that though 19.7% inquired had had problems after taking
drugs, at least once in their lives and only 36.7% had this reaction confirmed by a doctor
as an allergic reaction. Besides, 16.45% of the inquired people answered positively
when asked if they thought they were allergic to at least one drug.
In agreement with other studies [8, 11] we concluded that antiinfectious drugs, such as
penicillin, were the drugs reported to be the responsible for most self-reported drug
allergies. This can be due to the fact that Portugal has a high consumption of antibiotics
[12,13] and also because it’s a common medical practice to bane the consumption of
these drugs when the patient has already experienced a reaction to one drug of this
group (though it’s possible to occur specific reactions to the different molecules)
leading people to consider themselves allergic to all penicillin without any diagnostic
work-up.
In matter of fact it is important to point out that only 16.4% of the inquired did some
test or analysis to confirm drug allergy (meaning that only 23.3% of the people who
have experienced an adverse reaction did some test or analysis). These data are even
lower than those of identical studies [8].
The latter also explains, at least in part, that only 36.7% had the allergy confirmed by a
doctor. This can be also explained considering that some individuals consider
themselves allergic though they do not have a reasonable explanation, e.g. his/her
parents told him/her. It shows, however, that people were little curious (or they were
already convinced of what diagnose would be) and/or the means of diagnose were not in
reach.
We found no association between the occurrence of allergy (which is in agreement with
[6]) and the different age groups, but there is a statistically significant association
between the group that have felt sick due to drug’s intake and the group that think they
have allergy to drugs (p<0.05). The latter seems to us very reasonable, considering that
most people think that is allergic because they have already experienced a reaction,
though some have no reasonable explanation (vide supra).
The prevalence for having had an allergy confirmed by a doctor (11.2%) was in fact a
bit higher than in other studies [8,5], just like the percentage of inquired people who
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think they are allergic to drugs (16.45%), and as it is difficult to differ adverse drug
reaction and allergy to a drug using our questionnaire, the prevalence for self-reported
adverse drug reaction may also be considered high, in comparison to that studies. The
day periods we used to make the phone calls could have lead to some bias in our
sample, once the population that is at home at that time probably is less healthier than
the people that is not at home (working, shopping, studying, playing some sports, etc...).
However, it is said in the introduction that drug hypersensitivity reactions are thought to
represent 25% of adverse drug reactions [1]. If we bear this in mind, we can assume that
25% of this 19.7% are the actual drug allergy reactions, which will lead to the value of
4.9%, a value lower than the ones stated in other identical studies [8] but, nevertheless,
closer. The value 16.45%, which corresponds to the prevalence of people who think
they are allergic to drugs, can also be reduced by this idea. In the same way, probably,
the value 11.2% for the prevalence of having had an allergy confirmed by a doctor is
also slanted, as it is difficult to confirm that all this allergy reactions confirmed by a
doctor and reported by the inquired people were in fact drug allergy and not adverse
drug reactions. So, if the same principles are used, the actual value of drug allergy
confirmed by doctors will be lower, thus closer to the values presented in other studies.
Another conclusion was that the majority of the people that reported drug allergy were
allergic to one or two drugs. We shouldn’t forget however that the inquired can be
allergic to other drugs which they don’t know/experienced or forgotten.
Other conclusions have to due with the fact that 67% of those who felt sick due to
drug’s intake looked for medical assistance, although only 30% really needed medical
treatment; most common allergy symptoms were associated with the skin. These data
are in agreement with the conclusions of similar studies [8].
Although 17.8% of the inquired people reported that had an allergic disease, we
couldn’t establish an association between the occurrence of allergic disease and having
experienced an adverse drug reaction (p<0.05).
This study indicates highly prevalent self-reported drug allergies being the
dermatological most common; shows however that the reactions continue to be poorly
investigated.
Acknowledgments
To Dr. Luís Filipe Azevedo for the accompanying of the overall work and for solved
many of our problems.
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To Professor Altamiro da Costa Pereira for all the suggestions and critiques that made
us to improve our work.
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Available from: http://www.whocc.no/atcddd/
8. Gomes E, Cardoso MF, Praca F, Gomes L, Marino E, Demoly P. Self-reported drug
allergy in a general adult Portuguese population. Clin Exp Allergy. 2004
Oct;34(10):1597-601.
9. Gruchalla RS. Drug metabolism, danger signals, and drug-induced hypersensitivity.
J Allergy Clin Immunol. 2001 Oct;108(4):475-88.
10. Gruchalla RS. Drug allergy. J Allergy Clin Immunol. 2003 Feb;111(2
Suppl):S548-59.
11. Lazarou J, Pomeranz BH, Corey PN. Incidence of adverse drug reactions in
hospitalized patients: a meta-analysis of prospective studies. JAMA. 1998 Apr
15;279(15):1200-5.
12. Molstad S, Lundborg CS, Karlsson AK, Cars O. Antibiotic prescription rates vary
markedly between 13 European countries. Scand J Infect Dis. 2002;34(5):366-71.
DEPARTMENT OF BIOSTATISTICS AND MEDICAL INFORMATICS
FACULTY OF MEDICINE OF THE UNIVERSITY OF PORTO
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13. Cars O, Molstad S, Melander A. Variation in antibiotic use in the European Union.
Lancet. 2001 Jun 9;357(9271):1851-3.
DEPARTMENT OF BIOSTATISTICS AND MEDICAL INFORMATICS
FACULTY OF MEDICINE OF THE UNIVERSITY OF PORTO
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
Attachment 1: Questionnaire
Entrevistador:
Nome:___________________________________
Data:_____________
Número de telefone: Prefixo: _______________ Sufixo:_____
Hora de início da entrevista:________
Apresentação 1
Bom dia/tarde, o meu nome é …..
A Faculdade de Medicina da Universidade do Porto está a realizar um estudo acerca de alergias a
medicamentos na população adulta da região do Porto. Com a sua participação poderá contribuir para
melhorar os nossos conhecimentos nesta área, ajudando a tornar mais segura a toma de medicamentos a
quem deles precisa.
Para garantir a qualidade do estudo teremos que fazer uma selecção aleatória da pessoa a entrevistar em
sua casa. Por este motivo precisamos de entrevistar a próxima pessoa a fazer anos entre as pessoas com
mais de 18 anos que moram em sua casa.
A1 – Será possível falar com essa pessoa?
Sim
1
Não
0
Se sim passar para apresentação 2 abaixo, se não passar para A2
A2 – Será possível falar com essa pessoa numa outra altura?
Sim
1
Não
0
Se sim questionar sobre a melhor altura para contactar, se não considerar uma não resposta.
A3 – Quando poderei então contactar essa pessoa?
Dia ________________________________
Hora_____________________________
Apresentação 2
Bom dia/tarde, o meu nome é …..
A Faculdade de Medicina da Universidade do Porto está a realizar um estudo acerca de alergias a
medicamentos na população adulta da região do Porto. Com a sua participação poderá contribuir para
melhorar os nossos conhecimentos nesta área, ajudando a tornar mais segura a toma de medicamentos a
quem deles precisa.
A sua colaboração é por isto muito importante e requer unicamente a resposta a algumas perguntas
breves, que demorarão cerca de 5 minutos.
Q1 – Alguma vez, ao longo da sua vida, sentiu-se mal ou teve problemas por ter tomado um medicamento? (ao
responder a esta questão pense só nas ocasiões em que um medicamento lhe possa ter provocado uma reacção
indesejável para além das reacções mais banais e habituais, como por exemplo diarreia de curta duração, dores de
estômago ligeiras ou prisão de ventre passageira). Alguma vez, ao longo da sua vida, teve algum tipo de reacção a
medicamentos para além destas situações mais banais e habituais?
Sim
1
Não
0
Q2 – (Se sim em Q1) Com quantos medicamentos já lhe aconteceu sentir-se mal?
Nº ________
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
Q3.0 – (Se sim em Q1) Em alguma dessas ocasiões a reacção foi na pele (por exemplo manchas na pele, borbulhas,
comichão, inchaço, etc)?
Sim
1
Não
0
Se sim passar para Q3.1, se não passar para Q4.0
Q3.1 – Qual ou quais os medicamentos que estava a tomar nessa altura e que podem ter provocado essa
reacção? (se mais que uma ocasião mencionar só os da última dessas ocasiões)
Med 1 _____________________________
Med 2 ________________________________
Med 3 _____________________________
Med 4 ________________________________
Med 5 _____________________________
Med 6 ________________________________
Q3.2 – Era a primeira vez, ao longo da sua vida, que tomava esse(s) medicamento(s)?
Sim
1
Não
0
Q3.3 – Que idade tinha a última vez que teve este tipo de reacção na pele provocada pelo(s)
medicamento(s)?
___________ anos
Q3.4 – Quando esta reacção aconteceu, quanto tempo antes tinha tomado o medicamento?
Menos de 1 hora depois
1
Entre 1 hora e um dia depois
2
Mais de um dia depois
3
Q3.5 – Quanto tempo aproximadamente durou a reacção (em dias)? ______ dias
Q3.6 – Alguma vez teve essa mesma reacção sem estar a tomar medicamentos (sem que estivesse
relacionada com a toma de medicamentos)?
Sim
1
Não
0
Q4.0 – (Se sim em Q1) Em alguma dessas ocasiões a reacção foi respiratória (por exemplo falta de ar, aperto na
garganta, chiadeira, nariz a pingar, espirros, etc)?
Sim
1
Não
0
Se sim passar para Q4.1, se não passar para Q5.0
Q4.1 – Qual ou quais os medicamentos que estava a tomar nessa altura e que podem ter provocado essa
reacção? (se mais que uma ocasião mencionar só os da última dessas ocasiões)
Med 1 _____________________________
Med 2 ________________________________
Med 3 _____________________________
Med 4 ________________________________
Med 5 _____________________________
Med 6 ________________________________
Q4.2 – Era a primeira vez, ao longo da sua vida, que tomava esse(s) medicamento(s)?
Sim
1
Não
0
Q4.3 – Que idade tinha a última vez que teve este tipo de reacção na pele provocada pelo(s)
medicamento(s)?
___________ anos
Q4.4 – Quando esta reacção aconteceu, quanto tempo antes tinha tomado o medicamento?
Menos de 1 hora depois
1
Entre 1 hora e um dia depois
2
Mais de um dia depois
3
Q4.5 – Quanto tempo aproximadamente durou a reacção (em dias)? ______ dias
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FACULTY OF MEDICINE OF THE UNIVERSITY OF PORTO
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
Q4.6 – Alguma vez teve essa mesma reacção sem estar a tomar medicamentos (sem que estivesse
relacionada com a toma de medicamentos)?
Sim
1
Não
0
Q5.0 – (Se sim em Q1) Em alguma dessas ocasiões a reacção foi digestiva (por exemplo vómitos, diarreia grave
durante vários dias, dor de estômago intensa e persistente)?
Sim
1
Não
0
Se sim passar para Q5.1, se não passar para Q6.0
Q5.1 – Qual ou quais os medicamentos que estava a tomar nessa altura e que podem ter provocado essa
reacção? (se mais que uma ocasião mencionar só os da última dessas ocasiões)
Med 1 _____________________________
Med 2 ________________________________
Med 3 _____________________________
Med 4 ________________________________
Med 5 _____________________________
Med 6 ________________________________
Q5.2 – Era a primeira vez, ao longo da sua vida, que tomava esse(s) medicamento(s)?
Sim
1
Não
0
Q5.3 – Que idade tinha a última vez que teve este tipo de reacção na pele provocada pelo(s)
medicamento(s)?
___________ anos
Q5.4 – Quando esta reacção aconteceu, quanto tempo antes tinha tomado o medicamento?
Menos de 1 hora depois
1
Entre 1 hora e um dia depois
2
Mais de um dia depois
3
Q5.5 – Quanto tempo aproximadamente durou a reacção (em dias)? ______ dias
Q5.6 – Alguma vez teve essa mesma reacção sem estar a tomar medicamentos (sem que estivesse
relacionada com a toma de medicamentos)?
Sim
1
Não
0
Q6.0 – (Se sim em Q1) Em alguma dessas ocasiões teve outro tipo de reacções que não fossem na pele, respiratórias
ou digestivas?
Sim
1
Não
0
Se sim passar para Q6.1, se não passar para Q7.0
Q6.1 – Que tipo de reacção foi?
___________________________________________________________________
Q6.2 – Qual ou quais os medicamentos que estava a tomar nessa altura e que podem ter provocado essa
reacção? (se mais que uma ocasião mencionar só os da última dessas ocasiões)
Med 1 _____________________________
Med 2 ________________________________
Med 3 _____________________________
Med 4 ________________________________
Med 5 _____________________________
Med 6 ________________________________
Q6.3 – Era a primeira vez, ao longo da sua vida, que tomava esse(s) medicamento(s)?
Sim
1
Não
0
Q6.4 – Que idade tinha a última vez que teve este tipo de reacção na pele provocada pelo(s)
medicamento(s)?
___________ anos
DEPARTMENT OF BIOSTATISTICS AND MEDICAL INFORMATICS
FACULTY OF MEDICINE OF THE UNIVERSITY OF PORTO
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
Q6.5 – Quando esta reacção aconteceu, quanto tempo antes tinha tomado o medicamento?
Menos de 1 hora depois
1
Entre 1 hora e um dia depois
2
Mais de um dia depois
3
Q6.6 – Quanto tempo aproximadamente durou a reacção (em dias)? ______ dias
Q6.7 – Alguma vez teve essa mesma reacção sem estar a tomar medicamentos (sem que estivesse
relacionada com a toma de medicamentos)?
Sim
1
Não
0
Q7.0 – Em alguma dessas ocasiões teve que ir ao médico por causa dessa reacção?
Sim
1
Não
0
Se sim passar para Q7.1, se não passar para Q8.0
Q7.1 – Das reacções de que já falamos quais foram as que o(a) levaram a ir ao médico?
Da pele
1
Respiratórias
2
Digestivas
3
Outra (a indicada em Q6.1)
4
Q8.0 – Em alguma dessas ocasiões teve que ir fazer algum tratamento médico por causa dessa reacção?
1
Sim
0
Não
Se sim passar para Q8.1, se não passar para Q9.0
Q8.1 – Das reacções de que já falamos quais foram as que precisaram de tratamento médico?
Da pele
1
Respiratórias
2
Digestivas
3
Outra (a indicada em Q6.1)
4
Q9.0 – Alguma vez voltou a tomar de novo algum dos medicamentos que estava a tomar quando teve essa(s)
reacção(ões) indesejada(s)?
Sim
1
DEPARTMENT OF BIOSTATISTICS AND MEDICAL INFORMATICS
FACULTY OF MEDICINE OF THE UNIVERSITY OF PORTO
Não
0
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
Se sim passar para Q9.1, se não passar para Q10.0
Q9.1 – Voltou a ter os mesmos problemas/reacções quando tomou de novo esse(s) medicamento(s)?
Sim
1
Não
0
Q9.1 – Quais os nomes dos medicamentos com que voltou a ter problemas?
Med 1 _____________________________
Med 2 ________________________________
Med 3 _____________________________
Med 4 ________________________________
Med 5 _____________________________
Med 6 ________________________________
Q10.0 – Acha que é alérgico a algum medicamento?
Sim
1
Não
0
Se sim passar para Q10.1, se não passar para Q11.0
Q10.1 – Quais os medicamentos a que acha que é alérgico? (se grupos ou famílias de medicamentos indicar
a designação do grupo ou família)
Med 1 _____________________________
Med 2 ________________________________
Med 3 _____________________________
Med 4 ________________________________
Med 5 _____________________________
Med 6 ________________________________
Q11.0 – Alguma vez um médico lhe confirmou e lhe disse especificamente que era alérgico a algum medicamento?
Sim
1
Não
0
Se sim passar para Q11.1, se não passar para Q12.0
Q11.1 – Quais os medicamentos a que o médico lhe disse que era alérgico? (se grupos ou famílias de
medicamentos indicar a designação do grupo ou família)
Med 1 _____________________________
Med 2 ________________________________
Med 3 _____________________________
Med 4 ________________________________
Med 5 _____________________________
Med 6 ________________________________
Q12.0 – Alguma vez fez algum tipo de teste ou análise para saber se é alérgico a algum dos medicamentos com que
teve problemas e que foram atrás mencionados?
Sim
1
Não
0
Se sim passar para Q12.1, se não passar para Q13.0
Q12.1 – Quais as análises que fez para confirmar as alergias a medicamentos?
_________________________________________________________________________________
_________________________________________________________________________________
Q13.0 – Tem alguma doença alérgica?
Sim
1
Não
0
Se sim passar para Q13.1, se não passar para Q14.0
Q13.1 – Qual?
Asma
1
Rinite
2
Urticária
3
Outra
4
Qual? _________________
Q14.0 – Tem algum outro tipo de alergias (ex: alimentos, animais, pólens)?
Sim
1
DEPARTMENT OF BIOSTATISTICS AND MEDICAL INFORMATICS
FACULTY OF MEDICINE OF THE UNIVERSITY OF PORTO
Não
0
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DRUG ALLERGY PREVALENCE IN THE ADULT POPULATION
Se sim passar para Q14.1, se não passar para Q15.0
Q14.1 –É alérgico(a) a quê?
______________________________________________________________________________________
____________________________________________________________
Q15.0 – Sofre de alguma doença em particular?
Sim
1
Não
0
Se sim passar para Q15.1, se não passar para Q16
Q15.1 – Quais?
______________________________________________________________________________________
____________________________________________________________
Q16 – Qual é a sua idade? ___________ anos
Q17 – Sexo?
Masculino
1
Feminino
0
Q18 – Qual a sua Freguesia de residência? _____________________________________________
Chegamos ao fim da entrevista.
Muito obrigado pela sua valiosa colaboração.
DEPARTMENT OF BIOSTATISTICS AND MEDICAL INFORMATICS
FACULTY OF MEDICINE OF THE UNIVERSITY OF PORTO
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