Self-medication with antibiotics in Europe and its determinants Grigoryan, Larissa

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Are cultural dimensions relevant for explaining cross-national differences in antibiotic use in Europe?

Reginald Deschepper, Larissa Grigoryan,

Cecilia Stålsby Lundborg, Geert Hofstede, Joachim Cohen, Greta van der Kelen,

Luc Deliens, and Flora M Haaijer-Ruskamp on behalf of the SAR consortium

Submitted Chapter 6

AbstractAbstractAbstract

Objectives:Objectives:Objectives: To explore whether differences between national cultures as described in Hofstede’s model of cultural dimensions (, Individualism, Masculinity and ) are associated with cross-national differences in use of antibiotics (prescribed and non-prescribed). Methods:Methods:Methods: A survey on reported use of systemic antimicrobial drugs in the last 12 months (SAR- study) was conducted in 19 European countries. Country-level data from this survey were correlated to country-specific scores of cultural dimensions obtained from Hofstede. Results were verified by doing the same for data from 3 other studies on antibiotic use. Results: The SAR-study resulted in a response rate higher than 20% in 17 countries for which scores on the cultural dimensions were also available. The three other studies provided data on antibiotic use for 27 European countries in total, for which scores of cultural dimensions were also available. Significant positive correlations were found between Power Distance and prescribed (0.59) and non-prescribed (0.54) use of antibiotics. Data from the other 3 studies gave similar results. Uncertainty Avoidance was not significantly correlated with the data on antibiotic use from the SAR-study but was significantly positively correlated to the antibiotic use as reported in the three other studies. Individualism was significantly negatively correlated with self-medication (-0.41), but not with prescribed antibiotics. No significant correlations between Masculinity and antibiotic use were found. ConclusionsConclusions: Of the dimensions of national culture, in particular Power Distance seems to be associated with antibiotics use. Campaigns aimed at more rational antibiotics use thus require good understanding of national culture.

80 Are cultural dimensions relevant for explaining cross-national differences in antibiotic use in Europe?

Introduction

Antibiotics are important and widely used medicines (1,2). There is, however, a growing concern that the use and especially the unnecessary use of these medicines leads to resistance, avoidable costs and adverse reactions (1-3). Hence, a more prudent use of antibiotics has been advocated (4). There are considerable cross-national differences in public attitudes towards antibiotics use (5) as well as in actual use of prescribed antibiotics (2,6,7) and self-medications with antibiotics (8). These cross-national differences in use of antibiotics can only partially be explained by epidemiological differences and differences in health care structure. Cultural factors also are known to play an important role in illness behaviour and consumption of antibiotics (9). Most cross-cultural comparisons are about factors directly related to illness behaviour (e.g. labelling and presumed causes of illnesses). Few studies have explored the broader and general cultural characteristics of a country that at first sight are not directly related to illness behaviour (10). One of the difficulties in many studies is that the concept of culture is often used as a general concept for all inexplicable cross-national differences. It is also hard to operationalise the concept of culture into quantifiable measures that can be used in comparative studies. A possible solution is the use of cultural dimensions. These dimensions are aspects from which a culture can be compared with other cultures. They provide a relatively general framework for analysis that can be easily applied because it reduces the complexities of culture and its interactions into quantifiable dimensions (11-13). Based on surveys in more than 50 countries, Hofstede initially found 4 cultural dimensions on which countries can be scored: (i) Power Distance, (ii) Individualism, (iii) Masculinity and (iv) Uncertainty Avoidance. Power Distance refers to the degree of hierarchy in a country, it has been defined by Hofstede as the extent to which the less powerful members of organizations and institutions accept and expect that power is distributed unequally. Individualism refers to the prevalence of the interests of an individual versus the group. This dimension is defined as the degree to which individuals are integrated into groups. Masculinity, as opposed to femininity, refers to a culture in which the emotional roles between the genders are clearly separated; masculine cultures are for instance very assertive and competitive. Uncertainty Avoidance deals with a society's tolerance for uncertainty and ambiguity; this cultural dimension indicates to what extent a culture programs its members to feel either uncomfortable or comfortable in novel, unknown or surprising situations. Later, a fifth dimensions (Long Term versus Short Term Orientation) was found, based on Asian studies. While the influence of cultural dimensions on illness behaviour and use of medicines has been suggested in previous studies (14,15), very few studies have actually linked the scores on cultural dimensions with diseases and illness behaviour (16)

81 Chapter 6 and, to our knowledge, no study did this with regard to use of antibiotics. The aim of this study is to explore whether cultural dimensions, are associated with cross-national differences in the prescribed use of antibiotics and self-medication with antibiotics.

MaterialsMaterialsMaterials and methods

Data on prescribed use of antibiotics and self-medication were obtained from a survey in 2003 on reported use of systemic antimicrobial drugs in the last year in 19 European countries (SAR: Self-medication with antibiotics and Resistance in Europe). A multistage sampling design was used in each participating country. Within each country, a region with average prescribed antibiotic consumption was chosen, based on available national data on use of medicines. In each region an urban (with a population 75,000- 350,000) and a rural area (population 5,000- 10,000) were selected. Persons > 18 years of age were randomly selected from population registries in the selected regions. The questionnaire was developed specifically for this survey in English, translated into national languages, and back-translated for consistency. The questionnaire is available in English from the corresponding author. More information is provided elsewhere (8). Respondents were classified as self-medicating if they reported that they had taken any antimicrobial drugs in the previous 12 months without a prescription from a physician, dentist, or nurse and as prescribed users if antimicrobial drugs had been prescribed. For all countries in the SAR-study with a response rate higher than 20%, prevalence of reported self-medication and prescribed use of antibiotics in the previous 12 months per 1000 population were estimated (8). To verify whether the findings based on our data were consistent with results based on other studies and other European countries, we also made use of country-data on outpatient antibiotic use published by the European Surveillance on Antimicrobial Consumption (2), on reported use of antibiotics in the last year published by Eurobarometer (7), and on outpatients antibiotics sales using IMS data (6). In contrast to the data of the SAR-study, these other studies could not differentiate between prescribed antibiotics and self-medication with antibiotics. Data on cultural dimensions were obtained from Hofstede (13). We only used the 4 initial dimensions because data about the fifth dimension (Long Term Orientation) were only available for a limited number of countries. Scores on these dimensions, called indexes, indicate the relative positions of countries with regard to each other. For an initial set of 40 countries they were derived from carefully matched samples of employees in different national subsidiaries of the same multinational corporation (17). These relative positions turned out to be remarkably stable over time; they were replicated in a number of successive studies by different researchers using a variety of other matched samples of respondents (for an overview see Hofstede, 2001). Later additions used a simplified questionnaire, the Values Survey Module 1994 (18). It consists of 20 content questions and 6 demographic questions. The most recently

82 Are cultural dimensions relevant for explaining cross-national differences in antibiotic use in Europe? published lists contain index values on the first four dimensions for 74 countries and regions (13). Spearman’s correlation coefficient rho was used to calculate correlations between country- aggregated use of antibiotics and country-specific scores of cultural dimensions.

ResResResultsResultsultsults

There were 17 countries from the SAR-study (including 14,877 respondents) for which we had information on reported self-medication with antibiotics, prescribed use of antibiotics in the last 12 months and the scores on Hofstede’s cultural dimensions (table 1). Via the ESAC- study (24 countries), the Eurobarometer study (15 countries) and the study by Cars et al (15 countries) we disposed over similar data for in total 27 European countries (2,6,7). Significant positive correlations were found for Power Distance Index with prescribed use of antibiotics (0.59) and self-medication (0.54). Comparison with data available from other studies and other countries demonstrated significant correlations in the same directions (table 2). The Individualism Index is significantly negatively correlated with self-medication of antibiotics (-0.41). Moderate but non-significant correlations were found for prescribed use in the SAR-study and antibiotic use as reported in the other 3 studies. The Masculinity Index correlates moderately but non-significantly with self-medication (0.31) and prescribed use (0.42). This is consistent with the correlations based on the other studies. The finding of a positive correlation of Uncertainty Avoidance Index with self-medication (0.43) and prescribed use (0.32) is consistent with those of the other data sets. The correlations based on data of the SAR-study are however not significant, which they are for the data based on the other studies. The differences between correlation coefficients for prescribed use and self-medication are very small with regard to Power Distance and Individualism. For Masculinity and Uncertainty Avoidance they are somewhat higher.

83 84 Chapter 6

Table 1. SelfTable Self-Self---medication,medication, prescribed use of antibiotics in the past 1122 monthsmonths (prevalence rate per 1000 respondents) and indindexexeses of four cultural dimensions.

Country Response Rate No. Self-medication Prescribed use PDI IDV MAS UAI

(%) Respondents with antibiotics of antibiotics The 55 1634 1 152 38 80 14 53 Sweden 69 704 4 135 31 71 5 29 Denmark 63 1881 7 172 18 74 16 23 Luxembourg 50 675 9 288 40 60 50 70 Belgium (Flanders) 54 1734 9 222 61 78 43 97 Malta 54 541 56 422 56 59 47 96 Czech. Rep. 59 1169 7 253 57 58 57 74 Slovakia 55 546 42 569 104 52 110 51 Romania 43 430 198 307 90 30 42 90 Austria 28 442 9 159 11 55 79 70 United Kingdom 23 675 12 221 35 89 66 35 Ireland 26 793 14 353 28 70 68 35 Italy 21 213 62 512 50 76 70 75 Slovenia 38 1143 17 293 71 27 19 88 Croatia 31 615 31 439 73 33 40 80 Poland 32 935 33 199 68 60 64 93 Lithuania 25 747 210 275 42 60 19 65

Note: PDI (Power Distance Index); IDV (Individualism index); MAS (Masculinity); UAI (Uncertainty avoidance index)

Are cultural dimensions relevant for explaining cross-national differences in antibiotic use in Europe?

Table 2. Correlations between use of antibiotics and cultural dimensiondimensionssss

Power Individualism Masculinity Uncertainty

Distance Avoidance

SAR data

Self-medication 0.54* -0.41* 0.31 0.43 Prescribed use 0.59* -0.45 0.42 0.32

Other data sets

ESAC (N=24) 0.59** -0.29 0.22 0.59**

Eurobarometer (N=15) 0.62* -0.30 0.31 0.58*

Cars et al. (N=15) 0.78** -0.38 0.16 0.78**

** Correlation is significant at the 0.01 level (2-tailed). * Correlation is significant at the 0.05 level (2-tailed).

DiscussionDiscussionDiscussion

Power distance is positively correlated with self-medication and prescribed use of antibiotics in all the data sets. Uncertainty Avoidance, at first sight, does not seem to be relevant but significant positive correlations were found with antibiotic use as reported in other previous studies (partially based on other European countries). The findings for the Individualism and Masculinity are not conclusive, since not all data point out to significant correlations.

Power Distance

In countries with a high Power Distance inequality is expected and preferred. Subordinates will expect their superior to tell them what to do. In countries with a low Power Distance, to the contrast, people in less powerful positions will feel less dependent of more powerful people. They are expected to take initiatives and there is a preference for consultation. This may have implications for collaboration between doctors and other health care providers, such as pharmacists and nurses, as well as in the doctor-patient communication. An example of the former, is the collaboration between physicians and pharmacists. In countries with high Power Distance, hierarchic differences will be more manifested and doctors will have a more pronounced (therapeutic) autonomy, in other countries doctors feel more part of a team. In the Netherlands (a country with a low Power

85 Chapter 6

Distance and one of the lowest use of antibiotics) Pharmacotherapy Counselling Groups, in which GPs and local community pharmacists regularly meet to exchange information about drug therapy, has been the spearhead of a successful policy for more rational use of antibiotics and other medicines (10,19,20). Power Distance will also affect the doctor patient- relationship, besides the relations between professionals. In countries with a high Power Distance patients look up to their doctor. They expect great expertise of them and feel little need for being involved in the decision-making. Asking “what do you think yourself of taking an antibiotic?” would embarrass the ‘modal’ patient. Either so, a physician acknowledging that he is not sure whether it is a viral or bacterial infection and hence says: “well, let us wait and see” will, in such a cultural context, not inspire much confidence. Prescribing antibiotics has strong symbolic connotations and it can be seen as a sign of power and expertise. Hence, antibiotics not only have a pharmaceutical but also a communicative aspect. The clinician-patient encounter has been described as ‘one of the most important battlegrounds’ in the struggle with the microbe (21). Countries with low Power Distance, to the contrast, show a preference for shared decision- making in which the patient discloses his concerns and point of view, e.g. with regard to pros and cons of antibiotics. It is true that patients often put pressure on the physician to prescribe antibiotics but doctors often overestimate patients demand (22). Taking the time to talk about patients concerns and to make patient expectations explicit has been promoted as a good strategy to attain a more rational use of antibiotics (23-26). The finding that Power Distance is relevant with regard to use of antibiotics is in line with other studies (24) that indicate that doctor-patient relationship and dissatisfaction with the doctor is an important determinant of antibiotic misuse. Of four types of patients (involved, deferent, ignored and critical types), the Involved, i.e. patients which ensure they are part of the decision-making process and seeing themselves as equal to the doctor, have views on and use of antibiotics most in line with the medical views. Therefore, changing the patient to the more involved type is suggested as a strategy to limit the use of antibiotics. However this might be more difficult in countries with high Power Distance.

Uncertainty Avoidance

Uncertainty Avoidance deals with a society's tolerance for uncertainty and ambiguity. Typically, people in such societies can accept known risks but they try to avoid unclear situation and want to have control over things. If applied to medical situations, patients and physicians will have an aversion to diagnostic uncertainty and will prefer a clear labelling of diseases. However, many symptoms, such as coughing, sore throat, mild fever, etc. are difficult to label and remarkable cross-cultural variations have been found (14,27). Based on a clinical examination of the patient, it is often impossible to determine whether the problem is caused by a (self-limiting) viral infection or a bacterial infection, in which cases antibiotics might be

86 Are cultural dimensions relevant for explaining cross-national differences in antibiotic use in Europe? warranted (28). Hence, it is usually good practice to ‘wait and see’. However, there is always a small risk of a dangerous infection. If doctor and patient are not willing to accept risks, they rather start using antibiotics immediately, likely with a preference to the newest and strongest broad spectrum antibiotics. When the Uncertainty Avoidance is high, rather than returning home with the message that ‘the doctor does not know’ neither what disease they have, nor how to cure it, they accept the known risks of using antibiotics. In the latter case, patients feel confident that they have a disease with a clear cause that is under control. The above attitude of avoiding any risk is known as defensive medicine and leads to unnecessary high medical consumption (29).

Prescribed use versus self-medication

We found little differences between the effects of cultural dimensions on prescribed use versus self-medication of antibiotics. This suggests that in countries with high incidence of self-medication with antibiotics, the prescription of antibiotics is also high and that self- medication and prescribing are practices affected by the same cultural dimensions. This adds evidence to the hypothesis that notwithstanding the physician is formally the only person to decide whether or not antibiotics should be used, the final decision is the result of a complex interaction between patient and physicians in a particular cultural context. There is no indication in our data that behaviour with regard to use of antibiotics of physicians is less dependent of the local cultural context than that of the lay people (the patients). Our study had some limitations. First, the response rate for the SAR data was low in some countries. We therefore repeated the analysis, limited to countries with response rates of >40%. We also plotted the results and checked for the effect of possible outliers. These verifications corroborated our results. Second, culture is certainly a much richer phenomenon than the presented reduction into 5 dimensions and Hofstede has been criticized for trying ‘to measure the immeasurable’ (30,31). However, equivalents of Hofstede’s cultural dimensions were found by several other authors and the cultural dimensions were validated in multiple other studies (12). An advantage of the use of cultural dimensions is that they enable quantitative analysis of cultural aspects in relation to other relevant issues such as the use of antibiotics (11). This is not possible using thicker descriptions of cultures, i.e. anthropological descriptions based on qualitative data. In summary, our study indicates that Power Distance is a cultural aspect associated with antibiotic use, suggesting that the culturally-specific way people deal with authority is an important factor in explaining cross-national differences in antibiotic use. Uncertainty Avoidance can lead to defensive medicine which might result in unnecessary use of antibiotics. Further cross-national comparative research is needed to better understand the correlations between the cultural dimensions and the use of antibiotics and the reasons for this so that our

87 Chapter 6 hypothetical explanations can be corroborated or falsified. These findings and the deduced explanations suggest that countries are likely to react differently on campaigns aiming at a more rational use of antibiotics. It should be taken into account that cultural dimensions can be obstacles or facilitators which, by their nature, are hard to change (26,32). The understanding of the effect of cultural dimensions might explain why campaigns are less successful in some countries than in others (21, 26, 33-35). A better understanding of cultural dimensions can be used to anticipate reactions to a campaign in a particular country. For example, our results suggest that in countries with low Power Distance, campaigns for more appropriate use of antibiotics should involve both professionals and the general public, while in countries with high Power Distance campaigns to improve antibiotic use should focus primarily at the physicians.

Acknowledgements

The overall study was funded by the European Commission Public Health Directorate DG SANCO (SPC2002333). In addition, funding was also provided from funds of the participating institutions. The researchers of this study have been independent of funding source.

The SARThe SAR-SAR---consoconsoconsoconsortiumrtium

Antonella Di Matteo (Consorzio Mario Negri Sud, Santa Maria Imbaro, Chieti, Italy); Arjana Tambic-Andrasevic (University Hospital for Infectious Diseases, Zagreb, Croatia); Retnosari Andrajati (Faculty of Pharmacy, Charles University, Prague, Czech Republic); Hana Edelstein (Ha'Emek Medical Center, Afula, Israel); Rolanda Valinteliene (Institute of Hygiene, Vilnius, Lithuania); Reli Mechtler (University of Linz, Linz, Austria).

Transparency dddeclarationdeclarationeclarationeclaration

None to declare.

88 Are cultural dimensions relevant for explaining cross-national differences in antibiotic use in Europe?

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