Introduction and Definitions
The WHO1 defines adherence as “the extent to which a person’s behaviour – taking medica- tion, following a diet, and/or executing lifestyle changes, corresponds with agreed recommenda- tions from a health care provider” (p. 3). There are numerous ways in which behavior may not corre- spond with recommendations: non-adherence comprises behaviors such as not commencing performance of a recommended behavior (e.g. not exercising), cessation of a behavior too soon (e.g.
stopping medication prematurely), not perform- ing enough of the behavior (e.g. taking insufficient exercise to gain a benefit), and inconsistently per- forming the behavior (e.g. taking some medica- tions some of the time). A distinction is made between intentional and unintentional non- adherent behaviors. Unintentional non-adherence arises from not knowing the treatment regimen, forgetting to perform the behavior, misunder- standing the treatment regimen, dementia or cognitive impairment, stress, or psychological disturbance. In contrast, intentional non- adherence arises from a deliberate decision, which may be based on perceptions of symptom reduc- tion, fear of side-effects, fear of addiction, or per- ceived inefficiency of treatment.
Adherence in the Cardiac Context
Coronary heart disease (CHD) is a complex multifactorial disease and successful management places a variety of demands on the patient. The
explicit goals of cardiac rehabilitation (CR) are to enhance secondary prevention and to improve health-related quality of life. In order to achieve these goals, patients are typically presented with a variety of recommendations, including:
1. Take medication.
2. Follow dietary recommendations.
3. Quit smoking.
4. Perform regular exercise.
5. Manage stress.
6. Change work practices.
Extent of the Problem of Non-Adherence
It has been estimated that 20–80% of patients do not adhere to the basic requirements of a medical regimen2; however, it is important to note that adherence rates vary across regimen, setting, and populations, with the highest levels of non- adherence reported for preventive regimens in asymptomatic patients. Adherence to long-term therapy for chronic illnesses in developed coun- tries averages 50%,1and similar adherence rates have been reported in CHD patients.
Cardiac rehabilitation delivers secondary pre- vention for cardiovascular patients and promotes patient adherence. It is acknowledged that the major changes required of many patients are difficult to do on the basis of professional advice only. Cardiac rehabilitation is, effectively, a sophisticated adherence-promotion program using many techniques proven to promote and
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Adherence to Health Recommendations
David Hevey
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maintain behavior change in terms of promoting health and it has a beneficial effect on mortality, morbidity, and quality of life. However, despite these proven benefits, many eligible patients fail to attend: among those offered CR, the reported uptake rates range from 15% to 50%.3An evalua- tion of lifestyle changes among CHD patients in five European countries found that approximately 50% of patients changed lifestyles in accordance with recommendations.4 Similarly, there is evi- dence that only 50% of patients adhere to cardiac medication (e.g. statins, ACE inhibitors) 1 year after commencing treatment, and of those taking the drug, approximately 50% follow the treatment sufficiently to gain a therapeutic benefit.5 To date the majority of research on adherence among cardiac patients has focused on exercise adherence.6 There is less evidence regarding adherence to other behavioral recommendations of CR.
Consequences of Non-Adherence
Across illnesses, adherence is the single most important modifiable factor that compromises therapeutic outcome. The most efficacious treat- ment is made ineffective if the patient fails to adhere to it.Irrespective of whether non-adherence is intentional or non-intentional, it has substantial health and societal costs in terms of increased mor- bidity, mortality, and economic costs. A recent meta-analysis reported a 50% increase in the risk of adverse outcomes in non-adherent CHD patients.7 For example, in comparison to hypertensive patients who adhere, non-adherent hypertensive patients are four times more likely to be hospital- ized or to die from CHD.8In addition, the economic costs of non-adherence in the United States are considerable; a decade ago, it was estimated that medication non-adherence required $25 billion to pay for additional treatment and hospital admis- sions, and lost productivity due to non-adherence was estimated at $100 billion.9
Non-adherence produces unnecessary medical and psychosocial consequences of CHD, reduces quality of life, and wastes valuable healthcare resources. These consequences impair the ability of healthcare interventions such as CR to achieve therapeutic goals. Non-adherence produces
increased need for expensive health services (e.g., hospitalization, outpatient clinic visits) due to disease progression or relapse. Furthermore, the patient’s resumption and maintenance of normal social and vocational contributions is impaired.
The development of strategies to promote adher- ence offers considerable potential to provide substantial medical, psychological, and economic gains. Before considering possible interventions, it is necessary to examine the main predictors of adherence identified in the literature.
Causes of Non-Adherence
Adherence has typically been regarded as an issue for the patient only; however, it is increasingly recognized that adherence is a multilevel issue10 and consequently requires consideration of the illness and the treatment, the patient, the health- care provider, and the healthcare system.
Illness and Treatment Factors
Adherence is related to the specifics of the illness and treatment recommendations. In general,1 poor adherence is associated with treatments characterized by:
• long duration
• complex recommendations
• frequent changes in treatment
• side-effects
• treatment for asymptomatic conditions
• lack of immediate benefit
• high costs financially
• disruption to valued activities.
Behavior changes recommended for preventive purposes are at high risk for non-adherence.
For example, in asymptomatic conditions such as raised cholesterol levels and hypertension, patients feel no obvious benefit after medicines are taken. Indeed, the patients may report nega- tive side-effects to such medications. Further- more, cardiac patients are often faced with a complex regimen involving a number of different components that may interfere with their daily routine. Non-adherence is associated with the presence of co-morbid conditions, and many cardiac patients have concurrent diagnoses of
hypertension, hyperlipidemia, and type 2 diabetes that may compromise adherence.
Patient-Related Factors
Sociodemographic factors such as age, gender, ethnicity, socioeconomic status, and education have not been consistently related to adherence.1,2 A number of psychological factors have been investigated, including traits, states, knowledge, and beliefs. There is little evidence of personality traits influencing adherence and the search for the
“non-adherent” personality type has provided limited insight. Negative psychological states such as stress, depression, anxiety, and low levels of perceived social support increase the risk of non-adherence.2
Inadequate knowledge of illness and treatment, or misunderstanding of regimes could result in unintentional non-adherence. Nevertheless, knowledge alone is not sufficient for successful behavioral performance as there is substantial evidence that knowledge alone does not con- sistently predict behavior.1It has been suggested that the failure to adhere may reflect a failure to remember recommended behavior change, but even if the patient has adequate knowledge, accu- rate recollection of recommendations is not con- sistently associated with better adherence.11
The failure to find general patient-related factors as consistent predictors of adherence has resulted in a focus on specific beliefs that patients hold about their illness and treatment. A seminal series of investigations by Leventhal and col- leagues in the 1970s revealed that patients make sense of illness in terms of five specific types of illness representations:
1. Identity: what is the illness and what are its symptoms?
2. Causal attributions: what caused the illness?
3. Time-line: how long will it last?
4. Consequences: what are the physical, social, and economic implications of the illness?
5. Control: what can be done to manage and control the illness?
The patient’s beliefs about their illness and con- sequently how they think it should be managed may conflict with the healthcare provider’s beliefs, and consequently the patient may not adhere. Of
note, attendance at CR is related to illness repre- sentations. A recent randomized trial examined the efficacy of a brief three-session in-hospital intervention to change beliefs about a myocardial infarction in comparison to usual care.12 Three months after discharge from the hospital, the intervention group returned to work at a significantly faster rate and had fewer angina symptoms. Having favorable attitudes towards the behavior and high levels of self-efficacy (confidence in one’s ability to successfully perform the behavior) have been associated with successful performance of health behaviors.13
Healthcare Provider
Characteristics of the healthcare provider, such as communication style, can impact on rates of adherence. Communications associated with higher rates of adherence are characterized by providing information, being empathic, being clear, providing emotional support, allowing the patient to ask questions, and asking specific ques- tions about adherence.1,2,5 The patient’s percep- tions of being an active partner in the treatment process and being satisfied with the relationship with the healthcare provider also enhance adherence.
The multidisciplinary nature of CR offers a valuable forum for educating patients, motivating behavior change, monitoring behavior change, reinforcing messages, and providing feedback to patients. The multidisciplinary CR team’s effec- tiveness at promoting adherence can be enhanced through the diverse skills base of the CR team.
For example, the exercise specialist can encourage safe, effective, and regular practice of exercise strategies in a manner which promotes increased self-efficacy and habit formation: the dietician can illustrate how to “substitute” healthier behaviors or products rather than asking patients to under- take a loss-focused strategy of “removing”
unhealthy aspects of their dietary lifestyle; the psychologist can help manage psychological dis- tress that may inhibit adherence and, further- more, may provide inputs to the other members of the CR team in relation to motivating and rewarding behavior change.
To date, research has typically examined the adherence behavior of cardiac patients; the
adherence of healthcare professionals to evidence-based guidelines remains relatively understudied. Research evidence consistently reports non-adherence to recommended best practice. The EUROASPIRE I and II studies documented a substantial gap between standard clinical guidelines and actual clinical practice.14In general, secondary prevention of CHD is poorly integrated into clinical practice and this represents a substantial barrier to achievement of optimal health outcomes for patients. Furthermore, there is evidence that some health professionals lack confidence in changing patient behavior; for example, GPs and practice nurses reported a lack of confidence in their lifestyle counseling skills for cardiac patients.15Thus there is a critical need for healthcare professionals to receive appropriate training in the development and implementation of behavioral counseling skills in clinical practice.
Such training requires the support of the health- care system in which the service is embedded.
Healthcare System
Relatively little research has examined the effects of healthcare system-related factors on adherence.
Non-adherence has been associated with poorly developed health services, poor medication distri- bution systems, lack of knowledge and training for health professionals on managing chronic illnesses, overworked professionals, under- resourced services, lack of incentives and feed- back on performance, short consultation times, poor provision of follow-up, and inability to establish community support.1 Systems often fail to provide the continuity of care and ongoing contact (e.g. through telephone contact) that can help keep the patient engaged in the healthcare process. However, continuity of contact has cost and resource implications that may act as a barrier to implementation of such initiatives.
Summary
To fully understand adherence, we need to con- sider a particular patient experiencing a specific illness that requires a specific treatment in the context of a healthcare system. All of these factors contribute to the levels of adherence and to max- imize adherence, interventions need to target the
different levels. To date, research has typically only considered one of these levels – predominantly the patient – and consequently we have little evidence on the effectiveness of multilevel interventions.
Interventions
Numerous psycho-educational and behavioral strategies to enhance adherence have been examined (Table 35-1).
A meta-analysis which evaluated a range of interventions to improve adherence reported that they generally had a weak to moderate effect on adherence.16However, even modest improvements in adherence to behavioral recommendations could result in substantial mortality and economic costs. Combined-focus interventions were more successful than single-focus ones, and the most effective were a combination of educational, behavioral, and affective communications, which educated patients about their illness and treat- ment, taught behavioral strategies to enable people to cope better with symptoms and the behavior, and addressed emotions and moods.
Thus multilevel interventions offer a more effec- tive approach to enhancing adherence.
The CR team can use a number of the strategies presented in Table 35-1 in a coordinated manner.
Education is a core component of CR and the team includes healthcare professionals who have the specific knowledge and skills to ensure patients understand their condition and their treatment.
Healthcare providers should ask the patient about adherence at each visit. Acknowledgement that non-adherence occurs should be approached from an open, non-judgmental manner that avoids patient blaming. The use of open questions, showing empathy and following up on the patient’s verbal clues makes it easier for the patient to discuss barriers to good adherence. A partnership approach to developing solutions emphasizes that adherence is an issue for both patient and healthcare provider. Improved com- munication between the professional and the patient should result in more informed decision- making by the patient and greater levels of patient satisfaction. The increased involvement of the patient in the clinical discussion of treatment
recommendations can improve adherence, satis- faction, and outcome.
Cardiac patients require assistance in integrat- ing new demands into their daily routine. A focus on the positive benefits of adherence, rather than the negative effects of non-adherence, will help to achieve a positive outcome. Emphasis should be placed on the fact that adherence provides patients with the means to control the disease rather than the disease controlling them. A focus on short-term behavioral goals while highlighting the long-term objectives can facilitate adherence.
Short-term goals set around patient priorities, such as commencing regular exercise twice a week outside of the CR program, are achievable. Such successes should be reinforced and act as sources of confidence to achieve further goals. Strategies
aimed at increasing self-management using indi- vidual assessment, problem solving, goal setting, and follow-up show significant potential for enhancing adherence.17
A number of prompts and reminders have been demonstrated to improve adherence and the CR team can provide such prompts through provision of individualized reminder charts or diaries, sending postcard reminders, and telephone calls.
Furthermore, the family members and partners of the patients can be encouraged to provide such reminders. Indeed, partners are involved in the rehabilitation process in many CR services.
A recent systematic review17 examined inter- ventions to increase uptake of CR, patient adher- ence to CR, and healthcare provider adherence to CR. Provision of motivational communications TABLE35-1. Strategies for improving adherence to CHD secondary prevention behaviors
Strategy Aim
Education Communicate clearly the required information to the patient. Elicit what the patient understands about the illness and treatment. Clarify any misconceptions and provide written instructions if necessary.
Counseling Treat patient depression and anxiety and provide coping strategies to help manage stress.
Self-efficacy Increase patient confidence through provision of education, physiological feedback, vicarious experience,
enhancement and mastery experiences.
Social support Involve the patient’s spouse/partner/significant others to reinforce behavior change.
Problem solving Identify specific current or anticipated problems, generate potential solutions and determine a strategy, apply the strategy and evaluate in terms of successfully solving the problem.
Relapse prevention Identify the high-risk situations, consider different approaches to manage the high-risk scenario, rehearse selected coping strategy during imaginary scenarios.
Patient-centered Assist patients in making plans for behavior change and to help patients adhere to such plans. Actively counseling encourage patient involvement in the behavior change process.
Tailored behavioral Develop a feasible plan for behavior change that considers the patient’s characteristics, values, and skills.
change plan
Behavioral skill Provide instruction to help patient acquire and practice skills necessary to change behavior. Break behavior learning and rehearsal down into a series of manageable steps.
Stimulus control Identify the potentially modifiable antecedents to the non-adherent behavior, change the environment to remove triggering stimuli.
Specific goal setting Assist patients to make an explicit commitment outlining how specific behaviors are to be performed under specified circumstances.
Written agreement Develop an agreed contract with patient outlining the behavior change process in an explicit time frame.
Reinforcement Provide positive feedback to patient after successful achievement of a behavioral goal. Eventually the patient should be able to self-reward goal achievement.
Modeling Provide the patient with an appropriate credible model successfully performing the behavior.
Self-monitoring Review the patient’s log/diary of the behavior over time and provide feedback on performance.
Cueing by patient Establish a system of reminders for patient (e.g. notes in highly visible areas) to prompt the behavior.
Cueing by the Remind the patient of appointment schedules, send letters after missed appointments, send reminders for healthcare providers medication refill, provide medication calendars and pill boxes.
Ongoing support Contact the patient regularly to provide support to maintain behavior change. Support can be delivered through mail, phone, or e-mail.
Source: Adapted from Burke.23Copyright © 1999. Reproduced by permission of Routledge/Taylor & Francis Group, LLC.
using pamphlets, letters, or conversations with health professionals has been associated with improved uptake of outpatient CR. Improvements in CR referral have been reported in response to education of medical and nursing staff, electronic feedback and referral, and prompt card systems in the critical care pathway. A coordinated approach to transferring patients from hospital to general practice care, including cardiac liaison nursing support and patient self-management, can enhance uptake. The provision of support from trained lay volunteers offers another potentially useful strategy to increase adherence.
Few studies have examined ways to improve healthcare professionals’ adherence with CR and such studies tend to be characterized by poor methodological reporting. The main interven- tions used to date include improvement of the referral process, coordination of the patient’s post-discharge care, and formal recommendation of CR by the physician. Such approaches warrant further study as the conduct of the healthcare pro- fessionals is central to optimal CR utilization.
The CR program should be flexible in response to the patient’s needs. The provision of opportu- nities for patients to make decisions about the treatment course should help establish a collabo- rative approach. The CR service may need to offer a variety of programs with varied time commit- ments. For example, CR non-attenders often cite inconvenient timing as one reason for not attend- ing the program. Offering a variety of class times (including evening classes) should help attract those who may have other commitments (e.g. have returned to work). Innovative web-based technol- ogy combined with physician support may enhance adherence by healthcare staff in follow- ing up cardiac patients who leave the cardiac reha- bilitation program. Services may need to respond to the needs of different client groups (e.g.
women,18 older people,18 and those in lower socioeconomic status groups19) in imaginative and creative ways to increase uptake and reduce drop-out from the CR program.
Initial non-adherence predicts later non- adherence, and thus early intervention to promote adherence among patients is important in pro- moting more adherent behavior and enhancing long-term outcome. In essence, any approach to enhancing adherence has to be multidisciplinary
and multilevel and improving levels of adherence requires continued collaboration between health- care providers involved in the CR.
The costs of such interventions tend to be minimal, and some data suggest a cost-to-savings ratio of 1 : 10 for self-management strategies, with savings in terms of health service use.1However, it should be noted that the cost-effectiveness of the interventions used in CHD patients remains unclear due to lack of detailed information on the resources used in the studies. Given the intensive nature of some of these strategies, there is an absence of efficacy data on strategies in clinical practice.
Recent scientific statements on cardiac rehabil- itation and secondary prevention of CHD recom- mended that research should examine the effectiveness of interventions to promote adher- ence to secondary prevention recommenda- tions.20,21 In addition, adherence has been identified as a core expected outcome for cardiac rehabilitation services.22 Future research needs to address the identification of those patients at highest risk for non-adherence, methods for assessing and improving compliance, and strategies that facilitate long-term adherence to recommendations.
Summary of Strategies
To date, no one single intervention strategy, or combination of strategies, has been found to be effective across different patient populations, conditions, and settings. Therefore, interventions that target adherence must be tailored to the specific illness and treatment-related demands experienced by the individual patient in light of the particular social and cultural setting of the patient.
Conclusion
Non-adherence is not simply a patient problem;
aspects of health professional behavior and the healthcare system also contribute to non- adherence. Non-adherence needs to be routinely assessed as part of the therapeutic relationship between the patient and all professionals involved
in disease management. Optimal secondary prevention is impeded by non-adherence to recommendations. Although non-adherence is associated with substantial costs, both medically and economically, it is potentially modifiable.
Insights from behavioral science have highlighted the role of psychological factors in patient deci- sion-making regarding adherence and a number of promising intervention strategies have been developed with documented evidence of efficacy.
However, as yet, many of these strategies are not routinely incorporated into clinical practice.
Further research is required to identify key factors that explain adherence, and an integrated theoret- ical framework is needed to account for the relationship among such predictors. Such infor- mation will facilitate the development, imple- mentation, and evaluation of evidence-based interventions in clinical practice. The promotion of adherence strategies in a coherent, systematic manner offers great potential for decreasing health risks and unnecessary healthcare costs and improving patient outcomes. In the cardiac setting, since patient (and professional) adherence to long-term behavior change is intrinsic to much of the potential to benefit, activities to promote adherence must encompass individual patient, health professional, and system-related activities.
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