Authors

1. Macdonald, Marilyn RN, PhD
2. Martin-Misener, Ruth RN-NP, PhD
3. Helwig, Melissa MLIS
4. Smith, Lisa Janette RN, BScN, MSc
5. Godfrey, Christina M RN, PhD

Abstract

Review question/objective: The review question is: What are the experiences and perceptions of adults with cystic fibrosis and their adherence to a medication regimen?

Background: Cystic fibrosis (CF) is an autosomal recessive genetic disease, where a child has to inherit a copy of the CF gene from both parents in order to be affected. Cystic fibrosis affects various aspects of physiological function, including fluid secretion in the glands and lining of the respiratory, gastrointestinal, and reproductive tracts. These malfunctions could result in very thick secretions leading to lung infections, malnutrition, liver disease and intestinal obstruction. To aid with secretions, individuals with CF regularly take inhaled medications to decrease the viscosity of respiratory secretions, as well as enzymes that assist with digestion. In addition, these individuals frequently receive antibiotic therapy for infections and may practice regular breathing exercises to assist with the movement of secretions. Up to one third of adults with CF will develop diabetes, which they must also learn to manage.1,2 In general, adults experience more CF complications as they grow older, which increase the complexity of their treatment regimen. Additional complications of CF include: allergic bronchopulmonary aspergillosis, distal intestinal obstruction syndrome (DIOS), hemoptysis, pneumothorax, gastroesopageal reflux disease (GERD), liver disease, portal hypertension, CF-related arthritis/arthropathy, osteopenia/osteoporosis, nasal polyps, sinusitis, and asthma.3 Anxiety and depression are also more prevalent in the CF population.4 Patients who undergo lung transplants are faced with even more complicated regimens.5

Four thousand Canadian children have CF, and one in 3600 is born with the disease.1 These rates are similar to the US and the European Union, while CF is almost non-existent in Asia.6 These statistics reveal that CF is the most common life-limiting autosomal recessive genetic disease among Caucasians.7 In the 1960s, children diagnosed with CF rarely lived long enough to attend school.8 But advances in knowledge and treatment have raised life expectancy; half of the people diagnosed with CF are expected to live into their 40s, and almost 60% of the people in Canada living with CF are adults.1 A slightly higher percentage of males are affected by the disease.1 This is comparable with registry annual reports from other countries such as Australia, Belgium and the USA.9-11 Since the majority of individuals with CF are adults, this review will focus on adults aged 18 years and over.

Despite treatment advances, CF remains a life-limiting disease that requires a complex daily regimen of preventive and therapeutic interventions, and may require weekly clinic visits, repeated consultations, and frequent hospitalizations for treatment of pulmonary exacerbations and other CF complications.12-16 CF care is normally delivered through specialist medical centers and multidisciplinary teams that include specialist physicians, nurses, dietitians, physiotherapists, respiratory therapists, and pharmacists.3,17-19 This review is expected to provide: findings that further understanding of how adults living with CF experience taking medication for CF or related conditions, and strategies that enhance support for adults living with CF and taking prescribed medication.

Treatments

Cystic fibrosis is a complex disease. Learning to manage all its aspects and treatments can be a daunting task for patients and their caregivers. Individual treatment regimens depend on the stage of the disease and the organs affected. Successful CF management involves not only rigorous daily medication regimens but also a myriad of concurrent critical therapies such as airway clearance, exercise, and nutritional treatments.3,17,18,19-22 Lung treatments include daily medications such as antibiotics (oral, nebulized, IV) to help treat or control persistent infection, nebulized mucolytics to help break down mucus, making it easier to clear, bronchodilators to open the airways and relieve chest tightness and shortness of breath, and steroids to reduce inflammation in the airways.21 However, medications alone cannot keep CF lungs healthy. Daily airway clearance techniques (ACT) are essential to help move mucus out of the lungs (e.g. percussion and postural drainage, breathing techniques, autogenic drainage, positive expiratory pressure, high frequency chest wall oscillation and exercise). In addition, patients need to remember the recommended sequence for their lung treatments, change nebulizer sets for certain drugs, and spend time cleaning and disinfecting equipment every day. This is time consuming; however, if these treatments are not followed, there is an increased risk for infection, lung damage, and diminished lung function.22

Nutritional regimens are also critical. There is a link between body mass index and optimal lung function in people with CF.11 These treatments may include: a special diet (high caloric), pancreatic enzymes at every meal to help digest food, daily fat soluble vitamins, nutritional supplements (oral, or via tube), treatment or prevention of DIOS, increased fluids to prevent dehydration, medication for GERD.20 Many also need to perform blood glucose monitoring and insulin injections if they have CF-related diabetes.

Cystic fibrosis drastically impacts on the lives of both the affected adults and the family members who provide support and assist with disease management. Family members take on the role of policing medication and treatment regimens which can add to existing responsibilities substantially.23,12,24 Additionally, patients form partnerships with a myriad of providers, including physicians, nurses, dietitians, physiotherapists, pharmacists, respiratory therapists, social workers, and researchers.10 Despite the complexity and acuity of their disease, adults with CF are expected to become experts in their own care, manage their medications and treatments, and balance the rigorous demands that CF places on the rest of their lives.16,24-27 This is a substantial and arduous responsibility, given the propensity of medication-related adverse events in the Canadian health care system.28 In addition, the medications typically prescribed for these patients are pivotal to minimizing the adverse and life-threatening effects of their disease such as malnutrition, airway constriction, reduced pulmonary function, respiratory infection, and ultimately, survival.29

Adherence

The CF literature invariably reports patient non-adherence with medications and treatments yet does not define the concept of adherence.30 A comprehensive definition was found within the concept analysis of adherence,31 with the following deemed as the most widely used: "adherence is the extent to which patients follow the instructions they are given for prescribed treatments".31^(p.635) The concept analysis described the transition from the use of the term compliance to adherence. This coincided with the World Health Organization's adoption of adherence in 2003,32 in an attempt to move away from the tone of blame imposed on patients labeled non-compliant. The term adherence was believed to imply the patient was in agreement with the prescribed treatment and not simply following orders.31 However, Bissonnette31 noted that no definition of adherence truly recognized the patient as a partner in managing care, and called for exploration of the perceptions and understandings of individuals with CF and providers related to adherence.

Adherence rates in the CF population have been studied over several decades with reports dating to the 1950's. Conway, et al.33 reported treatment compliance at 50% in adults with CF responding to a self-report questionnaire. More recently, variations in rates by treatment have been reported, with adherence to digestive medications at 88.2%, respiratory medications at 61.8%, physiotherapy treatments at 41.2%, and nutritional supplements at 59%.34 Likewise, Latchford et al.35 reported adherence to nebulized antibiotics at around 50%. These two groups of researchers had conflicting reports of adherence by age, with Arias Llorente et al.34 reporting greater adherence in younger patients and Latchford et al.35 finding the opposite.

More than a decade ago, Abbott and Gee reviewed the literature related to barriers to CF treatment adherence and grouped their findings under four categories: 1) patients reported feeling well and therefore not appreciating the need for treatment; 2) treatments interfered with the social life of people with CF; 3) treatments were too time consuming; and 4) constant treatments make people with CF feel different than others.36 Further to this, the National Collaborating Centre for Primary Care (NCCP) Guideline30 reported communication failure as a source of non-adherence. More recent research on this topic confirms and extends this work. George et al.26 and Bregnballe et al.37 reported barriers that included treatment burden, social demands, work demands, forgetting, absence of perceived benefit, fatigue, and feeling embarrassed. Depression and anxiety have also been reported as barriers to adherence.4

Consequences of medication non-adherence in CF are significant and well-supported, including disease progression, increased infection rates, and increased direct (e.g. medication waste) and indirect costs (e.g. lost productivity of patients and families).36 A recent longitudinal retrospective pharmacy medication review of patients aged six and older measured adherence to respiratory medication to predict infection requiring intra-venous (IV) antimicrobials. This study was considered to be the first to demonstrate that non-adherence to respiratory medication can predict infectious exacerbations of CF symptoms.29 In 2010, 1,173 people with CF spent 23,146 days in hospital, and 749 courses of home IV antimicrobials were administered for respiratory exacerbations.1 Overall, the CF literature on adherence and guiding theories continues to locate the responsibility for medication adherence within the individual. A systematic review on the experiences of adults with CF in relation to taking medication has not been found in JBI, PROSPERO, OT Seeker, PEDro or in any of the databases in the proposed search strategy. Conducting this review may reveal individual as well as system factors that could be addressed for the support of taking prescribed medications.

In our discussion of adherence in CF, we covered not only medications but also the nutritional regimens as well as airway clearance techniques that capture the daily work required to maintain optimal health. The review, however, is focused on medication adherence since this topic is largely associated with medication and a comprehensive understanding of what is known about medication adherence from the perspectives of people with CF is necessary.