Evaluation of medical risk in dental practice through using the EMRRH questionnaire

CHANDLER-GUTIÉRREZ L, MARTÍNEZ-SAHUQUILLO A, BULLÓN-FERNÁNDEZ P. EVALUATION OF MEDICAL RISK IN DENTAL PRACTICE THROUGH USING THE EMRRH QUESTIONNAIRE. MED ORAL 2004;9:309-20.

ABSTRACT

Object: Due to the fact that the population is getting older and to new medical and dental techniques, the number of medical complications during treatment is tending to increase. In order to avoid these complications a correct clinical history should be obtained of all these patients. The search for a suitable questionnaire which would be able to take into account all these factors is therefore necessary. Material and Method: In this study we have used the questionnaire EMRRH which has been proposed by a group of European investigators, in order to study the prevalence of past medical problems in a population that attends a dental clinic for treatment. Results: A total number of 716 patients were registered. Of these, 219 had a medical history that was of some interest to us. There were significant differences between the average age of the population with or without former medical problems (p<0´0005). Secondly, out of the 30´6% of the population with medical problems (N=219), we separated into groups those patients who would have a low, medium or high risk of complications when submitted to dental treatment. 17´31% of the patients were classified as risk ASA II; 949´% as ASA III, and 2´51% as ASA IV. Among the diverse pathologies the highest percentage was hypertension (13´8%), followed by allergies to different drugs (8´37%), palpitations (7´82%), respiratory pathologies (5´16%) and diabetes (4´3%). Conclusion: We can see the obvious need for a detailed medical history to be taken because of the existing prevalence of these above pathologies taking into account that without one we could seriously harm the patient´s health with our dental treatment.

Key Words: ASA risk, medical history, medical background.

INTRODUCTION

Due to recent advances in Medicine, patients have a longer life-expectancy and many diseases can be controlled with a maintenance programme. This means that some patients may have to take long-term medication, which tends to make illness chronic. So “apparently healthy” patients, although they have serious chronic or past medical problems now have a good quality of life and may need dental treatment. The increase in age of the population, which has taken place in the last few years and will continue, means that there will be more patients taking medication, therefore more patients with a complicated medical history will need dental treatment (1, 2). In 2000, 15% of the European population was over the age of 65. It has been calculated that in the next 25 years this number will have doubled (2). As there is a higher incidence of illness due to age, the number of systemic illness will therefore increase. Patients often have significant medical problems and complications may arise during dental treatment. There is a direct relationship between patients with severe medical problems and age. Older patients now make up the “new” part of the population that attends dental clinics (2). It should be taken into account that these patients retain more of their teeth than in the past and need to attend a dental clinic more frequently.

Upon commencing treatment the dentist should make sure that these patients will not suffer any medical risk to their health. The study carried out by Abraham-Inpijn et al (1) in 7 countries shows that: in Great Britain there have been 120 deaths in dental surgeries over the last 10 years. In Holland, where there are 288 dentists, there were 208 emergencies in one year, including sudden death produced by a myocardial infarction.

This information shows the necessity of singling out patients with a high medical risk by means of recording their history. This is a legal document which lays down exactly the dentist / patient relationship. The information in this document should state the date of commencement of treatment, personal and family medical background anamnesis, the patients clinical history, examinations, check-ups and treatment carried out. This document should be considered of great legal importance and it is absolutely vital for every patient. The patient often denies having certain medical problems, as he considers them to be of no importance to the dentist. For this reason direct questioning should be the norm, in order to find out about any illnesses that could influence dental treatment. The search for an appropriate questionnaire has been the subject of several studies in recent years. One group of researchers, headed by Dr. Abraham-Inpijn from Holland, has drawn up a questionnaire: the European Medical Risk Related History questionnaire (EMRRH). It is hoped that in the future there will be the same questionnaire used by all European dentists.

The objective of this present study has been to use this questionnaire in order to find out the prevalence of medical risk related histories in the population that has attended our dental unit.

MATERIALS AND METHOD

All patients who attended the University Dental unit for the first time from 16th December 1998 to 26th May 1999 took part in this study. These patients completed the questionnaire before commencing treatment.

This questionnaire was the “European Medical Risk Related History” (EMRRH) (Fig.1) translated from the original Dutch questionnaire. At the same time the following information was also registered: sex, age, occupation.

There are 23 main questions in the “EMRRH” (in italics) and each contains one or more further specific questions. All questions are allotted an ASA grade from I to IV. When there is a negative reply to the main question the ASA risk is I. If the reply is affirmative the risk will be II, III or IV. The higher degree of ASA determines the level of risk in each question.

This information was kept on a data-base with a Microsoft Access 97 programme. The analysis was carried out with the SPSS programme. The standard median and deviation of the age of the general population and the population with and without medical histories was recorded. Within the group of patients with risk related histories information about each particular disease was taken and the percentage of people suffering from these diseases in relation to the general population was calculated. The average age of the population with and without risk related histories was compared using the Mann-Whitney test.

RESULTS

A total of 716 patients were studied. Their average age was 36.77 years with a standard deviation of 20.91 years. The age range was from 3 years to 83 years, 60% women, and 40% men. Their occupations were the following: students (31.8%), full-time employment (30%), housewives (27%), retired people (6.7%), unemployed (3.35%) and people unable to work living on a state pension (2%). 1.3% held a university degree, or similar.

Within this group of 716 patients, 219 had medical risk related histories (30.6%), 497 patients did not (69.4%). The average age of patients with medical risk related histories was 49.39 years with a standard deviation of 19.61 and ages ranging from 4 to 83 years. The group of patients without risk related histories had an average age of 31.20 years, a standard deviation of 18.97, and ages ranging from 3 to 82 years. These differences were statistically significant (Mann-Whitney test p<0.0005).

Within the group of patients with cardiovascular diseases 13.8% (n=99) of the total population suffered from hypertension. 9% of those patients (n=9) were classified as stage 1 (140-159; 90-99), 12.1% (n=12) as stage 2 (160-179; 100-109), and 38.3% (n=38) as stage 3 (>180; >110). The remaining 40.4% (n=40), in spite of taking medication to control their hypertension did not know their readings.From the following group of the total population, 7.82% (n=56) suffered from palpitations, 2.3% (n=17) had suffered from angina, 2.3% (n=17) had a heart murmur, 1.8% (n=13) had cardiac insufficiency, 0.5% (n=4) had suffered a myocardial infarction, 0.2% (n=2) had undergone cardiac surgery, and finally 0.1% (n=1) had a pace-maker.

The second most frequent medical risk related history group out of the total population of 716 patients suffered from drug-related allergy: 8.37% (n=60). No data was recorded from those patients suffering from other allergies, such as to dust, mites, pollen, etc. Within the group of patients with drug-allergies, 36% (n=22) were allergic to penicillin, 10% (n=6) to sulphamide , 5% (n=3) to both penicillin and sulphamide, 11.6% (n?7) to aspirin, 3.3% (n=2) to AINES, 3.3% (n=2) to amoxicillin, 1.6% (n=1) to local anaesthetics (procaine), 23.3% (n=14) of patients were allergic to other substances, such as mercuric iodide, latex, iodine, calcium, iron, acusine, codeine, etc. 3.3% (n=2) knew they suffered from some sort of allergy, but could not remember to what. From this group of allergic patients, 1.5% (n=11) when compared with the general population, had suffered a previous complication: they had needed to be hospitalised or take medication, and 0.2% (n=2) of these complications had occurred after taking medication prescribed by their dentist.

In the group of patients with respiratory problems, 5.16% (n=37) out of the total population frequently suffered from coughs, faringitis or the common cold. 3.77% (n=27) suffered from asthma or chronic bronchitis.

4.3% of the total population (716 patients) had diabetes; type I (insulin-dependent)1.5% (n=11) and type II (non-insulin dependent) 2.7% (n=20).

Patients having some type of infectious disease compared with the total population were classified as following: 3.77% (n=27) with hepatitis, 1.11% (n=8) had a medical history of hepatitis A; 1.53% (n=11) hepatitis B; 0.27% (n=2) hepatitis C; 0.13% (n=1) hepatitis A and B, and 0.13% (n=1) hepatitis b and C. 0.55% of patients within this group did not know which type of hepatitis they had suffered from. Out of the total population studied there were 1.53% (n=11) HIV carriers and 0.83% (n=6) claimed to be drug-addicts.

2.5% (n=18) of patients had thyroid disease. Within this group 1.3% (n=10) with goitre (struma), 0.8% (n=6) with hypothyroidism, 0.27% (n=2) with hyperthyroidism.

Further data showed that 1.53% (n=11) of the total population had a tendency to bleed, 1.11% (n=8) had epilepsy, 0.4% (n=3) were pregnant women, 0.1% (n=1) had anaemia, 6.9% (n=49) had anxiety attacks, 1.9% (n=14) had renal pathology, 1.6% (n=12) claimed to need antibiotic prophylaxis before dental treatment, 1.11% (n=8) had fainted in the course of a medical or dental treatment, and 0.4% (n=3) of the total population had suffered from cancer or leukaemia.

The question referring to the medication taken by patients showed that 24.1% (n=173) of the total population of 716 patients were taking some sort of medication. The highest percentage were patients taking medication for hypertension (10.75%; n=77), followed by 5.02% (n=36) who were taking anxiolytic medication. 4.6% (n=33) were taking analgesic medication, 3.63% (n=26) cardiac medication, 3.35% (n=24) antidiabetic drugs, 3.21% (n=23) medication for respiratory disease, 2.23% (n=16) medication for the skin or for the digestive system, 1.81% (n=13) anticoagulants, 1.67% (n=12) for thyroid disease, 1.25% (n=9) medication for HIV, 0.83% (n=6) anti-allergy drugs, 0.69% (n=5) antibiotics, 0.55% (n=4) claimed to take creative drugs, 0.41% (n=3) medication for epilepsy and 0.41% (n=3) steroids. Finally, 3.07% (n=22) of the total population were taking other medication, such as calcium, iron, diuretics, contraceptives or methadone hydrochloride and 1.39% (n=10) of patients did not know what medication they were taking.

The analysis of the level of risk according to the ASA classification showed that out of 716 patients, 69.4% (n=497) were within the ASA I group (they had no medical risk related history of any importance), 17.31% (n=124) were classified in group II. 9.49% (n=68) group III, and 2.51% (n=18) group IV. 1.25% (n=9) of patients with medical risk-related histories were not classified in any of these groups because their particular disease was not covered by the European medical questionnaire (EMRRH): 2 patients suffered from Crohn´s disease, 1 from celiac disease, 2 with Down's syndrome, 1 patients was 85% physically handicapped, 2 patients with Parkinson's disease, and 1 patient was deaf.

DISCUSSION

All patients who attended our unit at the University School of Dentistry were evaluated and studied during one academic year. The sample of the population does not correspond to a representative sample of the general population. But it does refer to a population that requires dental treatment and, at the same time, it can be considered representative of the type of patient that attends a dental practice. This fact is of utmost importance to dentists. One of the main characteristics of the patients in this study was the fact that very few had a university degree or similar. Therefore it can be deduced that they belong to a lower socio-economic society. The diseases included in this questionnaire have not been proven to be more prevalent according to the economic or educational levels of society. Therefore , these results can be considered to be valid when applied to the population in general. It must also be stressed that the sample is very large and that the patients attended the dental surgery not because of their medical risk related histories, but simply because they required dental treatment. For these reasons the results obtained in this study are relevant to the population that attends any dental surgery.

It has been seen in this study that there is a great prevalence of patients who suffer from some type of serious significant systemic disease, which is to be taken into account when they require dental treatment. When analysing the data for this study there was no other former similar study in our country, therefor the comparison has been made with studies carried out abroad.

The most numerous group of patients with a risk-related medical history belonged to those suffering from cardio-vascular disease. It is main cause of death in nearly all western countries. In 1994 the American Heart Association estimated that in the United States one out of every 6 men and one out of every 7 women aged between 45 and 64 years suffered from some type of cardio-vascular disease. This number increases with age and affects one in three people over the age of 65. Within the different types of cardio-vascular disease, one out of 4 patients suffers from hypertension. This means it is the highest factor of risk for suffering cardiac insufficising, and highest cause of renal insufficiency and myocardial infarction. Hypertension affects from 15% to 20% of adults in the United States (3). The prevalence of hypertension clearly increases with age. In our study the most frequent medical risk related histories belonged to patients suffering from hypertension, 13.8% of patients of the total population studied. The second most frequent cardiac related disease was palpitations (7.82% of patients). Little et al (3) proved there was a 17.2% prevalence of cardiac arrhythmia in a numerous population of patients (>10.000) and that over 4% of these were serious cardiac arrhythmias, or even potentially lethal. Simons et al (4), in a study of over 2.300 dentists found a prevalence of 15.6% of arrhythmias of which 4% were acute. Furberg et al (5) have calculated there is a global prevalence of cardiac arrhythmias in the United States of approximately 10%. This is according to the Cardiovascular Health Study, carried out in 1995 by the Heart, Lung and Blood Institute.

Within the group of patients suffering from ischemic cardiovascular disease a division has been made between those patients suffering from angina (2.3%) and those who have had a myocardial infarction (1.8%). It has been estimated that 20 million North Americans (8% of the population) have some form of heart disease. One out of every three men and one out of every ten women suffers from a cardiovascular disease before the age of 60 (6). In our study, cardiac insufficiency affected 1.8% of the population. Between one and two million people are affected in the United States. There are approximately 400.000 new cases every year (7). Patients over age 65 generally require hospitalisation, and at any age is the fourth most frequent method of treatment. Although mortality rates for myocardial infarction and ictus are decreasing, congestive cardiac insufficiency continues to be one of the main causes of death. The most common causes of this disease in the United States are coronary arterial disease, hypertension, myocardial disease and valvulopaty (8).

In this present study only 0.1% of the population required a pacemaker. In 1984 there were 500.000 permanent pacemaker users in the United States. In 1994 this figure had doubled and stood at one million people. At this moment in time more than 1.5 million people in the world require pacemakers. Each year 100.000 new pacemakers are fitted and the possible risks to users during treatment should be taken into account (9).

8.7% of the 716 patients in our study suffered from some kind of allergy. Only drug related allergies were studied as these are responsible for complications in dental treatment. Within this group 1.5% of the general population had suffered form a severe allergic reaction requiring hospitalisation and two cases had occurred after taking drugs prescribed after dental treatment. This fact is important as the dentist should take into account that patients may formerly have suffered from a severe allergy attach. It is estimated that 15-25% of United States citizens are allergic to some substance, and 6-10% of these allergies are drug-related (10). These allergies were manifest as erithema and skin rashes in 46%, urticaria 23%, permanent drug-related exanthemas 10%, multiform erithema 5% and anaphylactic shock 1% (10). There is a 1-3% risk entailed when administering a drug, and a 0.1% risk of allergic reaction leading to death.

There were 36.6% of patients with drug related allergies who were allergic to penicillin (3.07% of the total population). Different studies have shown that 5 to 10% of patients taking penicillin will have an allergic reaction, and 0.04%-0-2% will suffer an anaphylactic shock (10, 11). In a study of 151 deaths in the world caused by anaphylactic shock to penicillin (11), death was shown to have occurred 15 minutes after administration of the drug in 85% of cases, and the allergic reaction had commenced immediately after administration in 50% of cases. In 70% of cases these patients had formerly been administered penicillin (11). An interesting fact is that 0.6% of the general population are allergic to latex which should be considered important for dentists. Sussman et al (12) reported that latex had produced hypersensitivity in 14 people including workers in the health field. All 14 cases presented positive allergic reactions to latex and 4 cases had an anaphylactic reaction.

3.77% of patients from the general population (n=716), suffered from chronic bronchitis or asthma. In the United States EPOC is the fifth cause of death and it is estimated that 13.5 million people suffer from this disease. 14% of men and 8% of women are affected, and only arthrosis causes more physical handicaps and functional alterations over time. The incidence, prevalence and death rate of this disease, increases with age. White males are most at risk (13). However, asthma should be considered mainly a childhood disease which affects 10% of children (14). Although it is a world-wide problem, the incidence of asthma is still not clear. Its prevalence in Japan has tripled since the 60's, from 1.2 to 3.14% (15), and in the United States it has risen 40% from 1982-1992, from 3.47% to 4.94% (16).

More than 200 million people in the world suffer from diabetes mellitus. In the United States 2-4% of the population are diabetics. The prevalence of diabetes is 6 times higher than 40 years ago (17). Our research has shown that 4.3% of the total population were diabetics; 1.5% type I (insulin-dependent) and 2.7% type II. In the United States 90-95% of diabetics have type II diabetes (18). During the last years the incidence of diabetes type I has increased greatly in children and teenagers (18). The proportional distribution of type II diabetes rises from 8 cases per 100.000 at age 15, to 163 cases per 100.000 at age 65. This increase shows the effect of age on this disease. In a recent study it has been shown that diabetics patients (DMID) represent 2% of patients who attend a dental clinic, and that half of them do not even know that they suffer from this disease. This fact means that a detailed medical history should be taken by the dentist and then be forwarded to the patient's own physician.

Hepatitis is a world-wide health problem. There are 5 million new cases every year and over 300 million people are carriers of the virus. In the United States, viral hepatitis is the fifth of the infectious diseases that are obligatorily declared. Over one million North Americans are chronic carriers of the hepatitis virus (19).

In the United States, the incidence of hepatitis A has increased from 21.532 cases in 1983 to 24.238 cases in 1993 (19). Our study showed a prevalence of 1.11% patients with hepatitis A out of the general population.

Every year approximately 300.000 Americans become infected with VHB although only 13.301 cases were reported in 1993 (19). About 10.000 of reported cases require hospitalisation, and 350 people die yearly of acute infection (20). Many people who received blood transfusions and haemophiliacs who received treatment to replace their coagulation factor between 1960 and 1970 are infected with VHB. Our study showed a total of 1.53% of patients who were carriers of VHB out of the total population. As this disease can be asymptomatic or have sub clinical symptoms, most people do not even know they have suffered from this disease in the past or are suffering from it now. This is a medical risk related disease both for the dentist and the patient and great precautions should be taken to avoid infection.

The approximate incidence of hepatitis C carriers is 0.2-2.2% in developed countries. The prevalence among patients undergoing dialysis is 0.5% to 30% (21). In our study only 0.27% of patients had a medical history of infection with VHC. The main cause of infection is from blood transfusions. It has been shown that there is a prevalence of VHC between 0.1% of blood donors in northern Europe (22) and over 7% in some developing African countries (22). In a sample group of 55.587 Spanish blood donors, Muñoz Gomez et al (23) found 0.93% prevalence of anti-VHC, which is higher than that found in northern Europe but comparable with other Mediterranean countries, France (1.2%) or Italy (1.3%) (22, 23).

The World Health Organisation (WHO) has estimated that at the end of 1997 there were 30.6 million cases of HIV/AIDS. Europe is not one of the continents which is most affected by this pandemia. In Europe there have been 680.000 cases of HIV/AIDS reported up to the end of 1997, distributed increasingly from west to east. In 1994 in Spain, France, Italy and Switzerland (19% of the population of Europe) 74% of AIDS cases in the whole of Europe had been diagnosed, whereas in central and eastern Europe (except Rumania) and the new independent States of the Soviet Union (40% of the population of Europe) only 1% of AIDS cases had been diagnosed. At this moment in time in western Europe there are 530.000 cases in comparison to 150.000 cases in eastern Europe and former USSR countries (24). From 1990 onwards Spain has been the European country with the highest yearly/annual incidence of cases: 123 cases per million inhabitants in 1997, followed by Italy (60 cases per million), and Switzerland (50 cases per million). During 1997 there were 3.268 new cases of AIDS reported in Spain, which will have risen to 5.000 when all the relevant information has been received. In our study 1.53% of the total population claimed to be infected by HIV. However, there were some patients who said they were not infected but were drug-addicts (0.83%) and the same precautions should be taken with this group as it can be considered a high risk group.

There are very few reliable studies that show the prevalence by thyroid diseases. Studies carried out in Great Britain revealed 25-30 cases of hyperthyroidism per 10.000 women, and that this disease is 10 times more frequent in women. In our study the cases of hyperthyroidism were also in women. In the United States the incidence is 3 cases per 10.000 women each year.

In Great Britain there are 3 cases per 1000 women per year of hypothyroidism. It is estimated that there are 14 cases per 1000 women and 1 per 1000 men (25). In our study 0.8% of the total population suffered from hypothyroidism. In the United States hypothyroidism is 5-6 times more frequent than hyperthyroidism.

In our study 1.53%% of the total population claimed to have a tendency to bleeding, especially when taking anticoagulant medication. The use of this medication is considered to be high, although bleeding can be caused by other diseases. True haemophilia, or a deficient factor VIII, is the most frequent hereditary coagulation disorder. In the United States the total prevalence of haemophilia is about one case per 20.000 people. But, due to its genetic transmission there may be some areas presenting more cases than others. Von Willebrand's disease is the most frequent hereditary bleeding disease. It affects 1 out of 800-1000 people in the United States and is usually inherited in an autosomic dominant way (26).

It is estimated that 10% of the population will suffer at least one epileptic convulsion in their lives and the global incidence is 0.5% (27). Convulsions are more frequent in children, 4% of children suffer a convulsion during the first 15 years of life. Luckily these convulsions tend to disappear with age in most children. Approximately 1 out of every 15 patient claims that their convulsions take place after exposure to specific circumstances (blinking light, monotonous sounds, loud noises, video games, etc). (27). Convulsions can be controlled completely in 60-80% of epileptic patients. There is only partial control or inadequate control for the remaining patients. In our study it was found that 1.1% of the total population had suffered an epileptic crisis and they were being treated for this disease. It is very important to take this fact into account because in the dental surgery there are certain factors, especially stress, that could possibly trigger off an epileptic attack.

The last factor to be taken into account is the high number of patients who are taking some kind of medication, 173 people, which is nearly 25% of the total population. This is the consequence of the high level of medical backgrounds. It is known that all medication has secondary effects which often interfere with dental treatment. Therefor it is necessary to know exactly which medication the patient is taking.

After finding our the prevalence of the different diseases considered of importance in our study, the patients were classified according to their medical histories using the ASA system. This classification according to risk allows the dentist to distinguish between which patients can be treated with no problems involved and those whose treatment involves a great risk, however minimal that treatment may be. Similar studies using the same type of questionnaire have been carried out in other countries, where it was also shown that many patients had medical risk-related histories. For example, a study (2) carried out in Holland with 29.424 patients who attended a dental surgery, showed that 78% had an ASA risk I (with no medical risk histories); 12.7% ASA II; 5.7% ASA risk III and 3.5% ASA risk IV. In the population studied the most frequent disease was proved to be drug related allergies, having an 8.7% frequency in comparison to the total population. Cardiac disease was second, 6.8%, followed by hypertension (4.4%), chronic respiratory disease (3.2%) and endocrine problems (2.2%). There is a difference between this study and the study carried out in our university faculty. In our study the disease with the highest percentage of incidence was cardiac disease (13.8%), followed by drug related allergies (8.3%). In another study of importance of patient's medical history in relation to the ASA risk (European Medical Risk Related History) carried out by Abraham-Inpijn (28) the prevalence of different diseases suffered by patients attending dental surgeries was shown. For example, in Belgium (28,29) cardiac disease (13%) is the most frequent, followed by hypertension (9%), endocrine diseases (8%). In Germany cardiac disease is also the most frequent (25%), followed by drug related allergies (23%), anaemia (12%) and neurological diseases (9%).

In Belgium a study carried out with 248 patients (29) showed that in relation to risk related diseases 57% had no risk related medical histories (ASA I); 25% had ASA risk II; 11% ASA risk III; 7% ASA risk IV.

Therefore it should be considered that as there is such a high prevalence of patients with medical risk related histories, a correct medical history should be taken by the dentist. This can be carried out by means of a questionnaire which will enable the dentist to classify immediately the state of the patients health as ASA, healthy, or ASA II, III, and IV. This will help to avoid possible complications during dental treatment.

The main conclusion of our study is that it is necessary to carry out a complete clinical history of all patients, thereby avoiding any possible treatment that could put the patient's health or even his very life, at risk. One of the types of clinical histories that can be used is the EMRRH, due to its far-reaching and thorough questions. It is hoped that it will prove to be an invaluable tool for use in the dental practice.

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