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Two character traits associated with adherence to long term therapies
diabetes research and clinical practice 98 (2012) 19–25
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Diabetes Research and Clinical Practice journ al h ome pa ge : www .elsevier.co m/lo cate/diabres
Review
Two character traits associated with adherence to long term therapies Ge´rard Reach * Department of Endocrinology-Diabetology-Metabolic Diseases, Hospital Avicenne APHP and EA 3412, CRNH-IdF, University Paris 13, Bobigny, France
article info
abstract
Article history:
Adherence is defined as the adequacy between the behaviours of patients and their medical
Received 26 June 2012
prescriptions. Adherence is a general behaviour, which can explain why patients in the
Accepted 26 June 2012
placebo arm of randomised clinical trials have a lower mortality rate when they are
Published on line 13 July 2012
adherent. We propose that this behaviour is related to two character traits: patience
Keywords:
claim, we bring arguments from the literature and from two published personal studies. We
Adherence
previously showed that type 2 diabetic patients who respond as non-adherers to a ques-
Clinical myopia
tionnaire on adherence to medication and to whom one proposes a fictitious monetary
(capacity to give priority to the future) and, more provocatively, obedience. To support this
Patience
choice between receiving 500 euros today or waiting one year to receive 1500 euros never
Obedience
make the remote choice. We also showed that obese diabetic patients who declare that they
Empowerment
do not fasten their seat belt when they are seated in the rear of a car are more often non-
Patient education
adherent concerning medication than those patients who claim that they follow this road safety recommendation. Thus, one of the roles of empowerment and patient education could be to encourage the patients, if they wish it, to replace passive adherence behaviours with conscious active choices. # 2012 Elsevier Ireland Ltd. All rights reserved.
Contents 1. 2.
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Non-adherence, a major issue in contemporary medicine. . . . . . . . . . . . . . . . . . . . . . Non-adherence, a syndrome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1. A puzzling observation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2. The concept of homology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . First example of homology: non-adherence and addictions. . . . . . . . . . . . . . . . . . . . . 3.1. Non-adherence and addictions are often associated . . . . . . . . . . . . . . . . . . . . . 3.2. Provisional common mechanism: the weakness of the will . . . . . . . . . . . . . . . Behind the weakness of the will: impatience or the inability to prioritise the future . 4.1. The concepts of intertemporal choice and temporal horizon . . . . . . . . . . . . . . 4.2. Impatience, addictions and non-adherence . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3. Neurophysiological basis of impatience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
* Tel.: +33 148955158. E-mail address: [email protected]. 0168-8227/$ – see front matter # 2012 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.diabres.2012.06.008
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diabetes research and clinical practice 98 (2012) 19–25
Second example of homology: adherence to medication and seat belt use in the back of 5.1. Interpretation: homologous phenomena. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Practical implications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
How is it possible that some people can risk their lives by not adhering to a medical prescription? Consider the puzzling observation of non-adherence to immunosuppressive drugs in organ transplantation [1]. We propose that patient nonadherence represents a general behaviour related to the presence of two character traits, impatience and disobedience, and we will present some data in favour of this claim.
1. Non-adherence, a major issue in contemporary medicine Non-adherence or the absence of adequacy between the behaviours of the patients and the medical prescriptions represents a frequent phenomenon. A study using the Medication Possession Ratio (i.e. the ratio of the total days of the supply of medication dispensed divided by the number of days of the evaluation period) as a marker of adherence showed insufficient adherence (MPR < 80%) in approximately 25% of patients treated for hypertension, 35% of patients treated for diabetes and 63% of patients treated for hypercholesterolaemia [2]. This ratio decreases gradually to approximately 50% after two years of treatment, regardless of which drug is considered [3]. Studies showed a correlation between the degree of adherence and the percentage of patients with blood pressure [4], circulating LDL-cholesterol [5], and HbA1c [6] that are controlled by the treatment. In the diabetes field, a multivariate analysis showed that non-adherence is a determinant of the rate of hospitalisation and mortality of any cause [7]. Conversely, a good adherence is associated with a reduction in health expenses, primarily by a reduction in hospitalisations [8,9]. Not surprisingly, the World Health Organization declared that improving the effectiveness of interventions aimed at improving adherence would be more beneficial to health than any biomedical progress [10].
2.
Non-adherence, a syndrome
2.1.
A puzzling observation
In the Beta-Blocker Heart Trial, which evaluated the risk of death one year after a first myocardial infarction and compared the effect of an active drug with a placebo, the mortality rate of the patients who were non-adherent with the placebo was twice more important than that of the patients who took the placebo conscientiously [11]. The same result was found in a meta-analysis of all the studies in which this type of data was available [12]. More recently, better adherence to placebo was found to be associated with improved survival and lower rate of cardiovascular events in the Studies of Left Ventricular Dysfunction [13]. Moreover, a study investigating the effects of replacement hormonal therapy suggested that
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the women who were non-adherent in the placebo arm were at greater risk of death or developing cancer than the women who were adherent with the placebo [14]. In the same way, in the placebo arm of a study on the prevention of osteoporosis, the non-adherent women had more aggravation of their osseous mineral density score [15]. Being adherent to something, even when this thing does not contain anything (e.g., a placebo), suggests that one is adherent to all recommendations. For example, a study showed that women who are adherent to bisphosphonates are also adherent to statins; that they are more often nonsmokers; and that the results of a mammography or a colonoscopy are more commonly found in their files, which suggests that they comply with prescriptions [3]. Thus, a patient who is adherent to a recommendation, whatever it is, is also adherent to recommendations in general. Recommendations are in general supposed to protect health: by avoiding smoking and performing exercise, the adherent patient has a lower risk of dying of an infarction or experiencing worsening osteoporosis. These surprising observations led to the concept of the ‘‘healthy adherer’’ [12]. They also suggest that being an adherer could be explained by certain character traits.
2.2.
The concept of homology
Thus, non-adherence or adherence may represent a syndrome of which the various aspects may have a common mechanism. This property defines homology as opposed to analogy. To observe that the wings of a bird or a fly resemble each other is to note that they are similar objects and represents an analogy. To understand the reason of the resemblance of the two bones of the distal part of the upper limb of the human, the wing of the bird, the leg of the tortoise or the leg of the elephant is to notice the homology of these phenomena. When phenomena are homologous, they have a common mechanism that is a part of their explanation. This distinction can be applied to biological problems (the common mechanism being located at the level of embryogenesis) and human behaviours [16]. This can represent the basis of a method aimed at understanding the mechanisms behind non-adherence. In turn, understanding the mechanisms of adherence could be an essential step towards defining strategies aimed to improve it. We propose therefore to seek phenomena that are homologous with non-adherence and to investigate their mechanism. Those mechanisms would in turn represent explanations of the phenomenon of non-adherence. We will take two examples of homology: (1) that which exists between nonadherence and addictions, which will put us on the track of a first character trait, an impatient relationship to temporality and (2) that which exists between non-adherence to medication and the respect of the road code, which will suggest a role for a second character trait, disobedience.
diabetes research and clinical practice 98 (2012) 19–25
3. First example of homology: non-adherence and addictions 3.1.
Non-adherence and addictions are often associated
If addictions and non-adherence are homologous phenomena that depend on a common mechanism, then they should be often associated. Indeed, one can show for example that good adherence to antihypertensive therapy (more than 80% of the prescribed medication is purchased) is less often observed in the presence of addictions to drugs or alcohol [17] or that the practice of self-monitoring of blood glucose by diabetic patients is less frequent in smoking and alcoholic patients [18].
3.2. will
21
progressive loss of volitional control over drug taking’’ [23]. One can also find the intervention of the weakness of the will in tobacco addiction. A study of medical doctors showed that the majority of the non-smokers thought that individual will represents the most important force enabling them not to smoke [24]. In people who are not physically active, 39.2% of them refer to having a lack of will [25]. Approximately one-third of obese patients also refer to the lack of will to explain why they do not follow a prescribed diet [26], and one patient said before bariatric surgery: ‘‘I knew that nothing was going to change unless something stopped me’’ [27].
4. Behind the weakness of the will: impatience or the inability to prioritise the future
Provisional common mechanism: the weakness of the
If addictions and non-adherence are homologous phenomena, then they must have a common mechanism. Let us propose on a provisional basis the weakness of the will, or the lack of willpower, whose existence has long been recognised under the term akrasia. According to Plato [19], Socrates rejected the possibility that a person could knowingly act poorly: Socrates was entirely opposed to the view in question, holding that there is no such thing as incontinence; no one, he said, when he judges acts against what he judges best – people act so only by reason of ignorance. Aristotle answered [20]: Now this view plainly contradicts the apparent facts, and we must inquire about what happens to such a man; if he acts by reason of ignorance, what is the manner of his ignorance? It can appear strange to propose the intervention of a philosophical concept to explain a medical phenomenon. However, there are currently attempts to pave interdisciplinary links between philosophical and neurophysiological descriptions of dysfunctional decision making [21]. Furthermore, a quotation from a contemporary philosopher, Richard Holton, in connection with the strength of the will (willpower) can bring us back to the concept of ‘‘healthy adherer’’, which may explain, as shown above, the patient’s adherence to any prescription (which may be a placebo in a randomised clinical trial). For Holton, willpower is exerted on all the intentions of the person, who becomes able to abide by all of her resolutions [22]: ‘‘resolutions not to drink, not to smoke, to eat well, to exercise, to work hard, not to watch daytime television, or whatever, etc.’’ The weakness of the will is explicitly evoked in the case of the addictions. The poet Coleridge said about his addiction to laudanum: ‘‘an accursed habit, a wretched vice, a species of madness, a derangement, an utter impotence of the volition’’. More recently, addiction is described as an inability of individuals to manage their own consumption, consuming longer or more than they want, with unfruitful efforts to control consumption (DSM-IV). The psychiatrist George Loewenstein wrote: ‘‘as an individual becomes addicted to a drug, there is a
4.1. The concepts of intertemporal choice and temporal horizon With regard to non-adherence, treatments in chronic diseases primarily have the objective of prevention. The reward of nonadherence is abstract and bears on the long run (in fact, it is paradoxically never received – when they finally died, the patients did not have the complication of the disease!), whereas being non-adherent can be associated with a concrete and immediate pleasure (for example, avoiding the side-effects of the drugs or saving the time required to implement the treatment). In such an ‘‘intertemporal’’ choice [28], the remote and immediate rewards are often abstract and concrete, respectively, which is not fortuitous. The psychological theory of the Conceptual Levels of Trope and Liberman [29] predicts that the human mind often characterises concepts in this manner (if we think about reading in a remote way, we think in an abstract way that it enriches the mind; if we think about reading in an immediate way, we concretely think of the book that we are currently reading). Under these conditions, weakness of the will could represent an inability of some patients to prioritise the future by preferring immediate pleasures. Thus, impatience could represent a character trait associated with non-adherence to long-term therapies. On the contrary, prioritising the future could be the condition of adherence in chronic diseases [30]. The inability to project oneself into the future may explain the fact that non-adherence, in chronic diseases, is more frequent in younger patients [2], particularly in type 2 diabetes [31]. Indeed, a study suggested that the younger one is, the more one has difficult visualising oneself in the future [32]. Thus, the patient may think: why all these efforts, today, for somebody whom I have difficulty imagining? What is the link between this person and me? In Reasons and Persons, the English philosopher Derek Parfit wrote [33]: ‘‘My concern for my future may correspond to the degree of connectedness between me now and myself in the future [. . .] Since connectedness is nearly always weaker over longer periods, I can rationally care less about my further future’’. This effect of the relationship to temporality, considered here not within the immediate framework of the intertemporal
22
diabetes research and clinical practice 98 (2012) 19–25
choice but in the long run, could partly explain the phenomenon of non-adherence to long-term therapy, which we described as clinical myopia [34]. One arrives at the concept of a temporal horizon, which can be explored in the following way [35]: one asks people to make a list of ten events that will occur to them and to indicate the age at which they will experience them; one can thus determine the delay between their current age and the average date of the described events and the delay between this age and the latest event. Then, one presents to them two short stories that one asks them to complete and to indicate their duration (Story 1: Joe is drinking a cup of coffee. He thinks about what will occur when. . . Story 2: while awaking, Bill started to think about the future. In general, he expected that. . .). A study showed that, compared to non-smoking women, smokers had a shorter temporal horizon, evaluated by the events that one asked them to imagine. The temporal horizon, determined by the manner of completing the stories, was shorter in individuals with a low income [36]. In agreement with this assumption, one can also quote a study showing that women who favour the future more than the present are generally those women who request breast cancer screening [37].
4.2.
Impatience, addictions and non-adherence
A means of testing the way in which individuals behave vis-avis an intertemporal choice between a small immediate reward and a great remote reward is to use a fictitious monetary choice individuals are asked what they would choose between a small amount of money given now or a larger sum but given later. Using this monetary test, one finds a higher degree of impatience among smokers [38], alcoholics, other addicts [39] and obese [40] and overweight patients [41]. Recently, we proposed a fictitious monetary choice to a small cohort of 90 type 2 diabetic patients [42]. Thirty-nine patients agreed to wait one year for 1500 euros, 4 patients would wait 6 months for a sum of 800 euros, but 47 of the patients preferred to take 500 euros today. Analysing the answers to an adherence questionnaire derived from the questionnaire proposed by Girerd [43] resulted in 9 patients being classified as non-adherers. None of them waited one year for the 1500 euros ( p = 0.005), and none had a rate of HbA1c < 7% ( p = 0.011).
4.3.
Neurophysiological basis of impatience
Thus, some, but not all, individuals prioritise the present for reasons that may be psychological or genetic. As Jon Elster said [44], ‘‘it would be absurd to say that one preference is more rational than the other. Similarly, it is just a brute fact that some like the present, whereas others have a taste for the future. If a person discounts the future very heavily, consuming an addictive substance may, for him, be a form of rational behaviour’’. A study in which the monetary choice test was coupled with functional MRI analysis of the activity of certain cerebral zones showed the existence of a negative correlation between the degree of activity within a zone that should intervene in the capacity to make long-term decisions, the orbitofrontal cortex, and the degree of monetary
impatience and a positive correlation with cerebral zones that intervene in the reward circuits. Moreover, this study showed that the degree of impulsivity and the operation of these cerebral zones were different according to genetic polymorphism of an enzyme involved in the metabolism of cerebral amines, catechol-O-methyl transferase [45]. These data may therefore provide the foundation for a physiology of patience, the description of which represents one of the objects of the ‘‘neuro-economy’’ [46]. More precisely, from a neurophysiological point of view, impatience and patience are like a competition between two systems: choices for immediate outcomes are related to the limbic brain regions, while choices for delayed outcomes are related to the prefrontal cortex [47]. This last system develops completely after 20 years of age [48,49]. This could explain the particular vulnerability of teenagers to non-adherence. Thus, a study in teenagers and young adults who had had a heart transplant showed that the adherence to the immunosuppressive therapy was related to their degree of maturity [50]. This character trait could be present very early in some people, as shown by the famous marshmallow test. Walter Mischel showed that some 4-year-old children to whom one offers a marshmallow are able to wait 20 min without eating it if they are offered two marshmallows in return for not eating the first marshmallow within the given time frame. These children are able to wait, focusing their mind on an abstract representation of the marshmallow (e.g., it is like a cloud). These children took part in a longer study and about fifteen years later had a better adaptation to social life [51].
5. Second example of homology: adherence to medication and seat belt use in the back of a car Recently, we asked general practitioners to provide a questionnaire to 782 obese diabetic patients; this questionnaire explored their adherence to medication [42], their motivation, and whether they prioritise the future. We also asked them whether they usually attach their seat belt when they are seated in the back of a car [52]. Among these patients, 20.1% were regarded as nonadherent according to their answers to the adherence questionnaire. Table 1 shows that, compared to the adherent patients, the non-adherent patients more often had a HbA1c level higher than 7%, were more often smokers or ex-smokers, were more likely to declare that they do not follow their weight, were not motivated to take their treatment, and did not prioritise the future. This last observation is consistent with the assumption of an association between non-adherence and the relationship to the temporality, suggested in the first part of this text. In addition, we observed that the patients who declared that they did not fasten their seat belt in the back of a car were twice as likely (31.5% of the cases) to be non-adherent to medication than those patients who said that they fastened it (14.5%, p < 0.001). Conversely, in this population of patients, 32.2% of the patients declared that they did not fasten their seat belt in the back of a car. The percentage was twice more as high among non-adherent patients (51.1%) than among adherers to medication (27.5%, p < 0.001). In a multivariate
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diabetes research and clinical practice 98 (2012) 19–25
Table 1 – Characteristics of adherers and non-adherers to medication (results in %).
Non-adherers HbA1c > 7% Smokers, ex-smokers Do not follow their weight Not motivated Prioritise the future: no
All
Adherers
Non-adherers
p
20.1 58.3 25.4 48.7 46.9 60.6
54.3 22.8 43.3 40.9 58.3
74.2 35.8 70.1 70.4 70.0
<0.001 0.003 <0.001 <0.001 0.013
had a fine, and a study in the United States [56] showed that drivers in secondary seatbelt legislation states, where drivers are ticketed only when there is another citable traffic offence, wore their seatbelts significantly less often. This reinforces the idea that obedience to the law is the primary cause of this behaviour rather than the real wish to protect oneself. We thus propose that the adherence of patients to medication could in some cases simply be linked to another character trait, obedience to the recommendations that are given. In agreement with this idea, the patients in our investigation who disagree with the sentence ‘‘it is very good to follow the recommendations of the doctor’’ were more than twice as likely to be non-adherent to medication (48.9%) than those patients who agreed (22.2%, p < 0.001). One can bring this closer to the concept of reactance. Based on this psychological concept [57], an individual who feels that her freedom is threatened can refuse to be adherent simply because what one proposes was prescribed, and reactance can be a cause of non-adherence [58].
analysis, not fastening the seat belt was an independent factor associated with non-adherence to medication (relative risk = 2.3, 95% confidence interval 1.4–3.6, p = 0.0004).
5.1.
Interpretation: homologous phenomena
Fig. 1 presents the results of a multiple correspondence analysis that shows that the answers concerning adherence and seat belt use are very similar, suggesting that they are homologous phenomena. If they are homologous phenomena, the reasons of not fastening the seat belt could provide a psychological insight on the mechanism of non-adherence to medication. Langlie [53] and Williams and Wechsler [54] observed an association between the use of the seat belt and some health behaviours (medical checks-up, dental care, vaccination, exercise or dietary follow-up). However, the use of the seat belt could also have another meaning. A study in Malaysia [55] showed that the principal determinant for using a seatbelt was having already
2,0
1,5
Non-adherers B4 B12
seatbelt
Dimension 2 (8.0%)
1,0
0,5
B1
B3
Adherers A7
A6 A6
0,0
A16 6 A13 A10 A16 A1 A11 A14 A9 A11 A15A A A4 A 2 A2 A5 A 5 A1 A12 A8
-0,5
adherence
B2 B
B5 B15 B7
B6
B14 B 14B B9 B16
movaon B8 B11
B13
A3
B10
priority to the future
-1,0
-1,5 -1,0
-0,5
0,0
0,5
1,0
1,5
2,0
Dimension 1 (19.9%) Fig. 1 – Multiple correspondence analysis of the answers to the questionnaire, from reference [52]. A1, seatbelt fasteners; B1, seatbelt non-fasteners. A2, adherers; B2, non-adherers. A3, HbA1c = 7%; B3, HbA1c > 7%. A4, non-smoker; B4, ex-smoker/ current smoker. A5, follows weight on a regular basis; B5, does not follow weight. A6, motivated; B6, not motivated. A7, prioritise the future: yes; B7, do not prioritise the future. A8, ready to make efforts to improve diabetes control; B8, not ready. A9, recommendations are too strict: disagree; B9, agree. A10, not interested in changing lifestyle: disagree; B10, agree. A11, not a priority: disagree; B11, agree. A12, I have no time: disagree; B12: agree. A13, your health depends on you: agree; B13, disagree. A14, your health is very important: agree; B14, disagree; A15, the opinion of your family is very important: agree; B15, disagree. A16, following doctor’s recommendations is very good: agree; B16, disagree.
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diabetes research and clinical practice 98 (2012) 19–25
references
6.
Conclusion
We propose that two character traits could be associated with adherence to medication: motivation, largely directed by the patient’s relationship to temporality, and a more passive character trait, mere obedience. Some patients could have the two reasons to be adherent. The French word for adherence, ‘‘observance’’, initially had a religious connotation: adherence to the rule. Reintroducing such a notion of obedience in terms of the behaviours of the patients appears provocative nowadays when the autonomy of the patient is preached. We think that this new paradigm [59] may deny something obvious: certain patients are adherent, simply because they have the habit, in general, to be obedient to the recommendations that one gives them, for example, to fasten their seat belt when they sit in the rear of a car. One should not see here a breach in the respect of the principle of autonomy [60], but rather an illustration of the complexity of what is at stake in the doctor–patient relationship. Thus, the very role of empowerment, or more simply of patient education, could be to encourage patients, if they wish it, to be adherent not by mere obedience but by an active, conscious choice. The patient would become an agent, according to the definition given by Descartes in Passions of the Soul: a patient is somebody to whom things arrive, whereas an agent is somebody by whom the things arrive.
7.
Practical implications
The assumptions developed here could have practical implications in terms of interventions aiming at improving adherence. If non-adherence is due to a weakness of the will, one understands the interest of interventions relying on the techniques of motivational interview, aiming at helping the patients to clarify not only the barriers that they see in the effective realisation of their treatment but also the advantages of the treatment. The assistance of others could appear beneficial. If non-adherence is due to an inability to project oneself into the future (think in particular about the impact of social deprivation on non-adherence [61]) a solution could consist of seeking intermediate objectives closer than the abstract and remote idea ‘‘to avoid complications’’; perhaps, in our medical interview, when looking at the ‘‘history’’ of the patients, we may well look too much at their ‘‘antecedents’’ and not sufficiently at their projects. Lastly, if non-adherence is due to a disobeying character expressing reactance, presenting a treatment in a nonauthoritative way and suggesting that the final decision is in the patient’s hands could take all its significance within the framework of a modern medical practice.
Conflict of interest The author declares that he has no conflict of interest.
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patients with hypertension. Circ Cardiovasc Qual Outcomes 2009;2:451–7. Karter AJ, Ferrara A, Darbinian JA, Ackerson LM, Selby JV. Self-monitoring of blood glucose: language and financial barriers in a managed care population with diabetes. Diabetes Care 2000;23:477–83. Plato, Protagoras, 352b–358d.. Aristotle. Nicomachaen Ethics, Book VII, 2, p. 1–2. Kalis A, Mojzisch A, Schweizer TS, Kaiser S. Weakness of will, akrasia, and the neuropsychiatry of decision making: an interdisciplinary perspective. Cogn Affect Behav Neurosci 2008;8:402–17. Holton R. How is strength of will possible? In: Stroud S, Tappolet C, editors. Weakness of will and practical irrationality. Oxford: Clarendon Press; 2003. p. 39–67. Loewenstein G. A visceral account of addiction. In: Elster J, Skog OJ, editors. Getting hooked, rationality and addiction. 1999. p. 236. Memon SB, Memon AM. Why physicians and lay people smoke and how can it be reduced? J Pak Med Assoc 1999;49:2–4. Olmsted MP, McFarlane T. Body weight and body image. BMC Womens Health 2004;4(Suppl. 1):S5. Lo´pez-Azpiazu I, Martı´nez-Gonza´lez MA, Kearney J, Gibney M, Martı´nez JA. Perceived barriers of, and benefits to, healthy eating reported by a Spanish national sample. Public Health Nurs 1999;2:209–15. Ogden J, Clementi C, Aylwin S. The impact of obesity surgery and the paradox of control: a qualitative study. Psychol Health 2006;21:273–93. Loewenstein G, Read D, Baumeister RF, editors. Time and decision, economic and psychological perspectives on intertemporal choice. New York: Russel Sage Foundation; 2003. Trope Y, Liberman N. Temporal construal. Psychol Rev 2003;110:403–21. Reach G. Obstacles to patient education in chronic diseases: a transtheoretical analysis. Patient Educ Couns 2009;77:192–6. Lee R, Taira DA. Adherence to oral hypoglycemic agents in Hawaii. Prev Chronic Dis 2005;2:A09. Frederick S. Time preference and personal identity. In: Loewenstein G, Read D, Baumeister RF, editors. Time and decision, economic and psychological perspectives on intertemporal choice. New York: Russel Sage Foundation; 2003. p. 104. Parfit D. Reasons and persons. Oxford: Clarendon Press; 1984. pp. 313–314. Reach G. Patient non-adherence and healthcare-provider inertia are clinical myopia. Diabetes Metab 2008;34:382–5. Wallace M. Future time perspective in schizophrenia. J Abnorm Psychol 1956;52:240–5. Jones BA, Landes RD, Yi R, Bickel WK. Temporal horizon: modulation by smoking status and gender. Drug Alcohol Depend 2009;104(Suppl. 1):S87–93. Gurmankin Levy A, Micco E, Putt M, Armstrong K. Value for the future and breast cancer-preventive health behaviour. Cancer Epidemiol Biomarkers Prev 2006;15:955–60. Bickel WK, Yi R, Kowal BP, Gatchalian KM. Cigarette smokers discount past and future rewards symmetrically and more than controls: is discounting a measure of impulsivity? Drug Alcohol Depend 2008;96:256–62. Perry JL, Carroll ME. The role of impulsive behaviour in drug abuse. Psychopharmacology (Berl) 2008;200:1–26. Weller RE, Cook EWIII, Aswar KB, Cox JE. Obese women show greater delay discounting than healthy-weight women. Appetite 2008;51:563–9.
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[41] Ikeda S, Kang MI, Ohtake F. Hyperbolic discounting, the sign effect, and the body mass index. J Health Econ 2010;29:268–84. [42] Reach G, Michault A, Bihan H, Paulino C, Cohen R, Le Cle´siau H. Impatience is an independent determinant of poor diabetes control. Diabetes Metab 2011;37:497–504. [43] Girerd X, Hanon O, Anagnostopoulos K, Ciupek C, Mourad JJ, Consoli S. Evaluation de l’observance du traitement antihypertenseur par un questionnaire: mise au point et utilisation dans un service spe´cialise´. Presse Med 2001;30:1044–8. [44] Elster J, Skog OJ. Getting hooked, rationality and addiction. Cambridge University Press; 1999. p. 17. [45] Boettiger CA, Mitchell JM, Tavares VC, Robertson M, Joslyn G, D’Esposito M, et al. Immediate reward bias in humans: fronto-parietal networks and a role for the catechol-Omethyltransferase 158Val/Val genotype. J Neurosci 2007;27:14383–91. [46] Kalenscher T, Pennartz CM. Is a bird in the hand worth two in the future? The neuroeconomics of intertemporal decision-making. Prog Neurobiol 2008;84:284–315. [47] Bickel WK, Miller ML, Yi R, Kowal BP, Lindquist DM, Pitcock JA. Behavioral and neuroeconomics of drug addiction: competing neural systems and temporal discounting processes. Drug Alcohol Depend 2007;90S:S85–91. [48] Giedd JN. Adolescent brain development: vulnerabilities and opportunities. Ann NY Acad Sci 2004;1021:77–8. [49] Christakou A, Brammer M, Rubia K. Maturation of limbic corticostriatal activation and connectivity associated with developmental changes in temporal discounting. Neuroimage 2011;54:1344–54. [50] Stilley CS, Lawrence K, Bender A, Olshansky E, Webber SA, Dew MA. Maturity and adherence in adolescent and young adult heart recipients. Pediatr Transplant 2006;10:323–30. [51] Mischel W, Shoda Y, Rodriguez MI. Delay of gratification in children. Science 1989;244:933–8. [52] Reach G. Obedience and motivation as mechanisms for adherence to medication: a study in obese type 2 diabetic patients. Patient Prefer Adherence 2011;5:523–31. [53] Langlie JK. Interrelationships among preventive health behaviors: a test of competing hypotheses. Public Health Rep 1979;94:216–25. [54] Williams AF, Wechsler H. Interrelationship of preventive actions in health and other areas. Health Serv Rep 1972;87:969–76. [55] Mohamed N, Mohd Yusoff M, Isah N, Othman I, Syed Rahim SA, Paiman N. Analysis of factors associated with seatbelt wearing among rear passengers in Malaysia. Int J Inj Contr Saf Promot 2011;18:3–10. [56] Gillespie G, Al-Natour A, Marcum M, Sheehan H. The prevalence of seatbelt use among pediatric hospital workers. AAOHN J 2010;58:483–6. [57] Brehm JW. A theory of psychological reactance. New York: Academic Near; 1966. [58] Fogarty JS. Reactance theory and patient not-compliance. Soc Sci Med 1997;45:1277–88. [59] Lutfey KE, Wishner WJ. Beyond ‘‘compliance’’ is ‘‘adherence’’. Improving the prospect of diabetes care. Diabetes Care 1999;22:635–9. [60] Beauchamp T, Childress J. Principles of biomedical ethics. Oxford, New York, Toronto: Oxford University .Press; 2001 [61] Wamala S, Merlo J, Bostrom G, Hogstedt C, Agren G. Socioeconomic disadvantages and primary non-adherence with medication in Sweden. Int J Qual Health Care 2007;19:134–40.
Contents available at Sciverse ScienceDirect
Diabetes Research and Clinical Practice journ al h ome pa ge : www .elsevier.co m/lo cate/diabres
Review
Two character traits associated with adherence to long term therapies Ge´rard Reach * Department of Endocrinology-Diabetology-Metabolic Diseases, Hospital Avicenne APHP and EA 3412, CRNH-IdF, University Paris 13, Bobigny, France
article info
abstract
Article history:
Adherence is defined as the adequacy between the behaviours of patients and their medical
Received 26 June 2012
prescriptions. Adherence is a general behaviour, which can explain why patients in the
Accepted 26 June 2012
placebo arm of randomised clinical trials have a lower mortality rate when they are
Published on line 13 July 2012
adherent. We propose that this behaviour is related to two character traits: patience
Keywords:
claim, we bring arguments from the literature and from two published personal studies. We
Adherence
previously showed that type 2 diabetic patients who respond as non-adherers to a ques-
Clinical myopia
tionnaire on adherence to medication and to whom one proposes a fictitious monetary
(capacity to give priority to the future) and, more provocatively, obedience. To support this
Patience
choice between receiving 500 euros today or waiting one year to receive 1500 euros never
Obedience
make the remote choice. We also showed that obese diabetic patients who declare that they
Empowerment
do not fasten their seat belt when they are seated in the rear of a car are more often non-
Patient education
adherent concerning medication than those patients who claim that they follow this road safety recommendation. Thus, one of the roles of empowerment and patient education could be to encourage the patients, if they wish it, to replace passive adherence behaviours with conscious active choices. # 2012 Elsevier Ireland Ltd. All rights reserved.
Contents 1. 2.
3.
4.
Non-adherence, a major issue in contemporary medicine. . . . . . . . . . . . . . . . . . . . . . Non-adherence, a syndrome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1. A puzzling observation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2. The concept of homology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . First example of homology: non-adherence and addictions. . . . . . . . . . . . . . . . . . . . . 3.1. Non-adherence and addictions are often associated . . . . . . . . . . . . . . . . . . . . . 3.2. Provisional common mechanism: the weakness of the will . . . . . . . . . . . . . . . Behind the weakness of the will: impatience or the inability to prioritise the future . 4.1. The concepts of intertemporal choice and temporal horizon . . . . . . . . . . . . . . 4.2. Impatience, addictions and non-adherence . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3. Neurophysiological basis of impatience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
* Tel.: +33 148955158. E-mail address: [email protected]. 0168-8227/$ – see front matter # 2012 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.diabres.2012.06.008
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diabetes research and clinical practice 98 (2012) 19–25
Second example of homology: adherence to medication and seat belt use in the back of 5.1. Interpretation: homologous phenomena. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Practical implications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
How is it possible that some people can risk their lives by not adhering to a medical prescription? Consider the puzzling observation of non-adherence to immunosuppressive drugs in organ transplantation [1]. We propose that patient nonadherence represents a general behaviour related to the presence of two character traits, impatience and disobedience, and we will present some data in favour of this claim.
1. Non-adherence, a major issue in contemporary medicine Non-adherence or the absence of adequacy between the behaviours of the patients and the medical prescriptions represents a frequent phenomenon. A study using the Medication Possession Ratio (i.e. the ratio of the total days of the supply of medication dispensed divided by the number of days of the evaluation period) as a marker of adherence showed insufficient adherence (MPR < 80%) in approximately 25% of patients treated for hypertension, 35% of patients treated for diabetes and 63% of patients treated for hypercholesterolaemia [2]. This ratio decreases gradually to approximately 50% after two years of treatment, regardless of which drug is considered [3]. Studies showed a correlation between the degree of adherence and the percentage of patients with blood pressure [4], circulating LDL-cholesterol [5], and HbA1c [6] that are controlled by the treatment. In the diabetes field, a multivariate analysis showed that non-adherence is a determinant of the rate of hospitalisation and mortality of any cause [7]. Conversely, a good adherence is associated with a reduction in health expenses, primarily by a reduction in hospitalisations [8,9]. Not surprisingly, the World Health Organization declared that improving the effectiveness of interventions aimed at improving adherence would be more beneficial to health than any biomedical progress [10].
2.
Non-adherence, a syndrome
2.1.
A puzzling observation
In the Beta-Blocker Heart Trial, which evaluated the risk of death one year after a first myocardial infarction and compared the effect of an active drug with a placebo, the mortality rate of the patients who were non-adherent with the placebo was twice more important than that of the patients who took the placebo conscientiously [11]. The same result was found in a meta-analysis of all the studies in which this type of data was available [12]. More recently, better adherence to placebo was found to be associated with improved survival and lower rate of cardiovascular events in the Studies of Left Ventricular Dysfunction [13]. Moreover, a study investigating the effects of replacement hormonal therapy suggested that
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the women who were non-adherent in the placebo arm were at greater risk of death or developing cancer than the women who were adherent with the placebo [14]. In the same way, in the placebo arm of a study on the prevention of osteoporosis, the non-adherent women had more aggravation of their osseous mineral density score [15]. Being adherent to something, even when this thing does not contain anything (e.g., a placebo), suggests that one is adherent to all recommendations. For example, a study showed that women who are adherent to bisphosphonates are also adherent to statins; that they are more often nonsmokers; and that the results of a mammography or a colonoscopy are more commonly found in their files, which suggests that they comply with prescriptions [3]. Thus, a patient who is adherent to a recommendation, whatever it is, is also adherent to recommendations in general. Recommendations are in general supposed to protect health: by avoiding smoking and performing exercise, the adherent patient has a lower risk of dying of an infarction or experiencing worsening osteoporosis. These surprising observations led to the concept of the ‘‘healthy adherer’’ [12]. They also suggest that being an adherer could be explained by certain character traits.
2.2.
The concept of homology
Thus, non-adherence or adherence may represent a syndrome of which the various aspects may have a common mechanism. This property defines homology as opposed to analogy. To observe that the wings of a bird or a fly resemble each other is to note that they are similar objects and represents an analogy. To understand the reason of the resemblance of the two bones of the distal part of the upper limb of the human, the wing of the bird, the leg of the tortoise or the leg of the elephant is to notice the homology of these phenomena. When phenomena are homologous, they have a common mechanism that is a part of their explanation. This distinction can be applied to biological problems (the common mechanism being located at the level of embryogenesis) and human behaviours [16]. This can represent the basis of a method aimed at understanding the mechanisms behind non-adherence. In turn, understanding the mechanisms of adherence could be an essential step towards defining strategies aimed to improve it. We propose therefore to seek phenomena that are homologous with non-adherence and to investigate their mechanism. Those mechanisms would in turn represent explanations of the phenomenon of non-adherence. We will take two examples of homology: (1) that which exists between nonadherence and addictions, which will put us on the track of a first character trait, an impatient relationship to temporality and (2) that which exists between non-adherence to medication and the respect of the road code, which will suggest a role for a second character trait, disobedience.
diabetes research and clinical practice 98 (2012) 19–25
3. First example of homology: non-adherence and addictions 3.1.
Non-adherence and addictions are often associated
If addictions and non-adherence are homologous phenomena that depend on a common mechanism, then they should be often associated. Indeed, one can show for example that good adherence to antihypertensive therapy (more than 80% of the prescribed medication is purchased) is less often observed in the presence of addictions to drugs or alcohol [17] or that the practice of self-monitoring of blood glucose by diabetic patients is less frequent in smoking and alcoholic patients [18].
3.2. will
21
progressive loss of volitional control over drug taking’’ [23]. One can also find the intervention of the weakness of the will in tobacco addiction. A study of medical doctors showed that the majority of the non-smokers thought that individual will represents the most important force enabling them not to smoke [24]. In people who are not physically active, 39.2% of them refer to having a lack of will [25]. Approximately one-third of obese patients also refer to the lack of will to explain why they do not follow a prescribed diet [26], and one patient said before bariatric surgery: ‘‘I knew that nothing was going to change unless something stopped me’’ [27].
4. Behind the weakness of the will: impatience or the inability to prioritise the future
Provisional common mechanism: the weakness of the
If addictions and non-adherence are homologous phenomena, then they must have a common mechanism. Let us propose on a provisional basis the weakness of the will, or the lack of willpower, whose existence has long been recognised under the term akrasia. According to Plato [19], Socrates rejected the possibility that a person could knowingly act poorly: Socrates was entirely opposed to the view in question, holding that there is no such thing as incontinence; no one, he said, when he judges acts against what he judges best – people act so only by reason of ignorance. Aristotle answered [20]: Now this view plainly contradicts the apparent facts, and we must inquire about what happens to such a man; if he acts by reason of ignorance, what is the manner of his ignorance? It can appear strange to propose the intervention of a philosophical concept to explain a medical phenomenon. However, there are currently attempts to pave interdisciplinary links between philosophical and neurophysiological descriptions of dysfunctional decision making [21]. Furthermore, a quotation from a contemporary philosopher, Richard Holton, in connection with the strength of the will (willpower) can bring us back to the concept of ‘‘healthy adherer’’, which may explain, as shown above, the patient’s adherence to any prescription (which may be a placebo in a randomised clinical trial). For Holton, willpower is exerted on all the intentions of the person, who becomes able to abide by all of her resolutions [22]: ‘‘resolutions not to drink, not to smoke, to eat well, to exercise, to work hard, not to watch daytime television, or whatever, etc.’’ The weakness of the will is explicitly evoked in the case of the addictions. The poet Coleridge said about his addiction to laudanum: ‘‘an accursed habit, a wretched vice, a species of madness, a derangement, an utter impotence of the volition’’. More recently, addiction is described as an inability of individuals to manage their own consumption, consuming longer or more than they want, with unfruitful efforts to control consumption (DSM-IV). The psychiatrist George Loewenstein wrote: ‘‘as an individual becomes addicted to a drug, there is a
4.1. The concepts of intertemporal choice and temporal horizon With regard to non-adherence, treatments in chronic diseases primarily have the objective of prevention. The reward of nonadherence is abstract and bears on the long run (in fact, it is paradoxically never received – when they finally died, the patients did not have the complication of the disease!), whereas being non-adherent can be associated with a concrete and immediate pleasure (for example, avoiding the side-effects of the drugs or saving the time required to implement the treatment). In such an ‘‘intertemporal’’ choice [28], the remote and immediate rewards are often abstract and concrete, respectively, which is not fortuitous. The psychological theory of the Conceptual Levels of Trope and Liberman [29] predicts that the human mind often characterises concepts in this manner (if we think about reading in a remote way, we think in an abstract way that it enriches the mind; if we think about reading in an immediate way, we concretely think of the book that we are currently reading). Under these conditions, weakness of the will could represent an inability of some patients to prioritise the future by preferring immediate pleasures. Thus, impatience could represent a character trait associated with non-adherence to long-term therapies. On the contrary, prioritising the future could be the condition of adherence in chronic diseases [30]. The inability to project oneself into the future may explain the fact that non-adherence, in chronic diseases, is more frequent in younger patients [2], particularly in type 2 diabetes [31]. Indeed, a study suggested that the younger one is, the more one has difficult visualising oneself in the future [32]. Thus, the patient may think: why all these efforts, today, for somebody whom I have difficulty imagining? What is the link between this person and me? In Reasons and Persons, the English philosopher Derek Parfit wrote [33]: ‘‘My concern for my future may correspond to the degree of connectedness between me now and myself in the future [. . .] Since connectedness is nearly always weaker over longer periods, I can rationally care less about my further future’’. This effect of the relationship to temporality, considered here not within the immediate framework of the intertemporal
22
diabetes research and clinical practice 98 (2012) 19–25
choice but in the long run, could partly explain the phenomenon of non-adherence to long-term therapy, which we described as clinical myopia [34]. One arrives at the concept of a temporal horizon, which can be explored in the following way [35]: one asks people to make a list of ten events that will occur to them and to indicate the age at which they will experience them; one can thus determine the delay between their current age and the average date of the described events and the delay between this age and the latest event. Then, one presents to them two short stories that one asks them to complete and to indicate their duration (Story 1: Joe is drinking a cup of coffee. He thinks about what will occur when. . . Story 2: while awaking, Bill started to think about the future. In general, he expected that. . .). A study showed that, compared to non-smoking women, smokers had a shorter temporal horizon, evaluated by the events that one asked them to imagine. The temporal horizon, determined by the manner of completing the stories, was shorter in individuals with a low income [36]. In agreement with this assumption, one can also quote a study showing that women who favour the future more than the present are generally those women who request breast cancer screening [37].
4.2.
Impatience, addictions and non-adherence
A means of testing the way in which individuals behave vis-avis an intertemporal choice between a small immediate reward and a great remote reward is to use a fictitious monetary choice individuals are asked what they would choose between a small amount of money given now or a larger sum but given later. Using this monetary test, one finds a higher degree of impatience among smokers [38], alcoholics, other addicts [39] and obese [40] and overweight patients [41]. Recently, we proposed a fictitious monetary choice to a small cohort of 90 type 2 diabetic patients [42]. Thirty-nine patients agreed to wait one year for 1500 euros, 4 patients would wait 6 months for a sum of 800 euros, but 47 of the patients preferred to take 500 euros today. Analysing the answers to an adherence questionnaire derived from the questionnaire proposed by Girerd [43] resulted in 9 patients being classified as non-adherers. None of them waited one year for the 1500 euros ( p = 0.005), and none had a rate of HbA1c < 7% ( p = 0.011).
4.3.
Neurophysiological basis of impatience
Thus, some, but not all, individuals prioritise the present for reasons that may be psychological or genetic. As Jon Elster said [44], ‘‘it would be absurd to say that one preference is more rational than the other. Similarly, it is just a brute fact that some like the present, whereas others have a taste for the future. If a person discounts the future very heavily, consuming an addictive substance may, for him, be a form of rational behaviour’’. A study in which the monetary choice test was coupled with functional MRI analysis of the activity of certain cerebral zones showed the existence of a negative correlation between the degree of activity within a zone that should intervene in the capacity to make long-term decisions, the orbitofrontal cortex, and the degree of monetary
impatience and a positive correlation with cerebral zones that intervene in the reward circuits. Moreover, this study showed that the degree of impulsivity and the operation of these cerebral zones were different according to genetic polymorphism of an enzyme involved in the metabolism of cerebral amines, catechol-O-methyl transferase [45]. These data may therefore provide the foundation for a physiology of patience, the description of which represents one of the objects of the ‘‘neuro-economy’’ [46]. More precisely, from a neurophysiological point of view, impatience and patience are like a competition between two systems: choices for immediate outcomes are related to the limbic brain regions, while choices for delayed outcomes are related to the prefrontal cortex [47]. This last system develops completely after 20 years of age [48,49]. This could explain the particular vulnerability of teenagers to non-adherence. Thus, a study in teenagers and young adults who had had a heart transplant showed that the adherence to the immunosuppressive therapy was related to their degree of maturity [50]. This character trait could be present very early in some people, as shown by the famous marshmallow test. Walter Mischel showed that some 4-year-old children to whom one offers a marshmallow are able to wait 20 min without eating it if they are offered two marshmallows in return for not eating the first marshmallow within the given time frame. These children are able to wait, focusing their mind on an abstract representation of the marshmallow (e.g., it is like a cloud). These children took part in a longer study and about fifteen years later had a better adaptation to social life [51].
5. Second example of homology: adherence to medication and seat belt use in the back of a car Recently, we asked general practitioners to provide a questionnaire to 782 obese diabetic patients; this questionnaire explored their adherence to medication [42], their motivation, and whether they prioritise the future. We also asked them whether they usually attach their seat belt when they are seated in the back of a car [52]. Among these patients, 20.1% were regarded as nonadherent according to their answers to the adherence questionnaire. Table 1 shows that, compared to the adherent patients, the non-adherent patients more often had a HbA1c level higher than 7%, were more often smokers or ex-smokers, were more likely to declare that they do not follow their weight, were not motivated to take their treatment, and did not prioritise the future. This last observation is consistent with the assumption of an association between non-adherence and the relationship to the temporality, suggested in the first part of this text. In addition, we observed that the patients who declared that they did not fasten their seat belt in the back of a car were twice as likely (31.5% of the cases) to be non-adherent to medication than those patients who said that they fastened it (14.5%, p < 0.001). Conversely, in this population of patients, 32.2% of the patients declared that they did not fasten their seat belt in the back of a car. The percentage was twice more as high among non-adherent patients (51.1%) than among adherers to medication (27.5%, p < 0.001). In a multivariate
23
diabetes research and clinical practice 98 (2012) 19–25
Table 1 – Characteristics of adherers and non-adherers to medication (results in %).
Non-adherers HbA1c > 7% Smokers, ex-smokers Do not follow their weight Not motivated Prioritise the future: no
All
Adherers
Non-adherers
p
20.1 58.3 25.4 48.7 46.9 60.6
54.3 22.8 43.3 40.9 58.3
74.2 35.8 70.1 70.4 70.0
<0.001 0.003 <0.001 <0.001 0.013
had a fine, and a study in the United States [56] showed that drivers in secondary seatbelt legislation states, where drivers are ticketed only when there is another citable traffic offence, wore their seatbelts significantly less often. This reinforces the idea that obedience to the law is the primary cause of this behaviour rather than the real wish to protect oneself. We thus propose that the adherence of patients to medication could in some cases simply be linked to another character trait, obedience to the recommendations that are given. In agreement with this idea, the patients in our investigation who disagree with the sentence ‘‘it is very good to follow the recommendations of the doctor’’ were more than twice as likely to be non-adherent to medication (48.9%) than those patients who agreed (22.2%, p < 0.001). One can bring this closer to the concept of reactance. Based on this psychological concept [57], an individual who feels that her freedom is threatened can refuse to be adherent simply because what one proposes was prescribed, and reactance can be a cause of non-adherence [58].
analysis, not fastening the seat belt was an independent factor associated with non-adherence to medication (relative risk = 2.3, 95% confidence interval 1.4–3.6, p = 0.0004).
5.1.
Interpretation: homologous phenomena
Fig. 1 presents the results of a multiple correspondence analysis that shows that the answers concerning adherence and seat belt use are very similar, suggesting that they are homologous phenomena. If they are homologous phenomena, the reasons of not fastening the seat belt could provide a psychological insight on the mechanism of non-adherence to medication. Langlie [53] and Williams and Wechsler [54] observed an association between the use of the seat belt and some health behaviours (medical checks-up, dental care, vaccination, exercise or dietary follow-up). However, the use of the seat belt could also have another meaning. A study in Malaysia [55] showed that the principal determinant for using a seatbelt was having already
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movaon B8 B11
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1,5
2,0
Dimension 1 (19.9%) Fig. 1 – Multiple correspondence analysis of the answers to the questionnaire, from reference [52]. A1, seatbelt fasteners; B1, seatbelt non-fasteners. A2, adherers; B2, non-adherers. A3, HbA1c = 7%; B3, HbA1c > 7%. A4, non-smoker; B4, ex-smoker/ current smoker. A5, follows weight on a regular basis; B5, does not follow weight. A6, motivated; B6, not motivated. A7, prioritise the future: yes; B7, do not prioritise the future. A8, ready to make efforts to improve diabetes control; B8, not ready. A9, recommendations are too strict: disagree; B9, agree. A10, not interested in changing lifestyle: disagree; B10, agree. A11, not a priority: disagree; B11, agree. A12, I have no time: disagree; B12: agree. A13, your health depends on you: agree; B13, disagree. A14, your health is very important: agree; B14, disagree; A15, the opinion of your family is very important: agree; B15, disagree. A16, following doctor’s recommendations is very good: agree; B16, disagree.
24
diabetes research and clinical practice 98 (2012) 19–25
references
6.
Conclusion
We propose that two character traits could be associated with adherence to medication: motivation, largely directed by the patient’s relationship to temporality, and a more passive character trait, mere obedience. Some patients could have the two reasons to be adherent. The French word for adherence, ‘‘observance’’, initially had a religious connotation: adherence to the rule. Reintroducing such a notion of obedience in terms of the behaviours of the patients appears provocative nowadays when the autonomy of the patient is preached. We think that this new paradigm [59] may deny something obvious: certain patients are adherent, simply because they have the habit, in general, to be obedient to the recommendations that one gives them, for example, to fasten their seat belt when they sit in the rear of a car. One should not see here a breach in the respect of the principle of autonomy [60], but rather an illustration of the complexity of what is at stake in the doctor–patient relationship. Thus, the very role of empowerment, or more simply of patient education, could be to encourage patients, if they wish it, to be adherent not by mere obedience but by an active, conscious choice. The patient would become an agent, according to the definition given by Descartes in Passions of the Soul: a patient is somebody to whom things arrive, whereas an agent is somebody by whom the things arrive.
7.
Practical implications
The assumptions developed here could have practical implications in terms of interventions aiming at improving adherence. If non-adherence is due to a weakness of the will, one understands the interest of interventions relying on the techniques of motivational interview, aiming at helping the patients to clarify not only the barriers that they see in the effective realisation of their treatment but also the advantages of the treatment. The assistance of others could appear beneficial. If non-adherence is due to an inability to project oneself into the future (think in particular about the impact of social deprivation on non-adherence [61]) a solution could consist of seeking intermediate objectives closer than the abstract and remote idea ‘‘to avoid complications’’; perhaps, in our medical interview, when looking at the ‘‘history’’ of the patients, we may well look too much at their ‘‘antecedents’’ and not sufficiently at their projects. Lastly, if non-adherence is due to a disobeying character expressing reactance, presenting a treatment in a nonauthoritative way and suggesting that the final decision is in the patient’s hands could take all its significance within the framework of a modern medical practice.
Conflict of interest The author declares that he has no conflict of interest.
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