How effective is a patient centred approach in improving medication adherence in patients with chronic open-angle glaucoma? Rapid literature review
Author: Alex Johnston
Date: January 2013
Abstract
Poor patient adherence is one of the most significant healthcare issues, particularly in patients with chronic disease such as chronic open-angle glaucoma. Treatment failure often leads to increased resource utilisation, more frequent hospital appointments and diagnostic tests, increases in doses or changes in medications and risk to the patients if subsequent surgical intervention is required.
The purpose of this study was to review and critically appraise the current research available on the effectiveness of patient centred interventions for improving medication adherence in patients with chronic open-angle glaucoma and identify those interventions that are most effective.
Nine studies met the inclusion criteria. All but one advocate patient centred approaches. Four studies recommend utilising office staff/glaucoma educators. In the only phenomenological study the use of narrative captured patient’s subjective experiences with glaucoma therapy.
The studies included have variable aims and researchers have utilised a range of different outcome measures making direct comparison between studies difficult. Also, lack of longitudinal evidence, small sample size and restrictive exclusion criteria made it difficult to make firm, evidence-based recommendations about the most effective interventions.
However, factors that appear to positively contribute to improved adherence include ongoing patient education, patient centred communication techniques, the use of office staff/glaucoma educator and multifaceted interventions.
Further large scale trials, and methodologically rigorous research is recommended to determine which components of intervention are most effective.
How effective is a patient centred approach in improving medication adherence in patients with chronic open-angle glaucoma?
Introduction
Chronic open angle glaucoma (COAG) is a common and potentially blinding condition. It is usually asymptomatic until advanced and many people will be unaware there is a problem with their eyes until severe visual damage has occurred. Ocular hypertension (OHT) is a major risk factor for developing glaucoma although COAG can occur with or without raised eye pressure.
Approximately 2% of the population over 40 years of age has glaucoma rising to almost 10% in people older than 75 years. The prevalence may be higher in people of black African or black Caribbean descent or who have a family history of glaucoma (NICE, 2009). In Northern Ireland it is estimated that 18, 650 people are affected by glaucoma (Little, 2009).
As there is no cure for glaucoma and vision loss is irreversible effective control of intraocular pressure (IOP) is the only means to delay or prevent progression at present. The majority of patients are initially managed with medical therapy but despite the availability of very effective topical drug therapies (eye drops) an estimated thirty to fifty per cent of patients do not take their medications as prescribed. (Olthoff et al, 2005; Nordstrom et al 2005; Okeke et al, 2009).
There are a number of terms to describe whether medications are taken as prescribed. An extensive literature search revealed that adherence has superseded the term compliance as it has fewer negative connotations, implies a more active or collaborative process and is intended to be non-judgmental (MacLaughlin et al, 2005). Adherence will therefore be used throughout this review however, the search strategy will incorporate both terms and any other terminology associated with adherence.
Non adherence to treatment has significant effects on treatment outcomes often leading to increased resource utilisation, more frequent hospital appointments and diagnostic tests, increases in doses or changes in medications and risk to the patients if subsequent surgical intervention is required (Gray et al, 2010)
Barriers to glaucoma treatment adherence include situational and environmental factors (major life events, travel, competing activities); medication regimen factors (refill, complexity, adverse events, cost); patient related factors (knowledge, memory, motivation, comorbidity, health beliefs) and provider related factors (satisfaction with and communication by clinicians) (Taylor et al, 2002; Noecker, 2009)
Recent reviews of studies in patients with many different chronic conditions reveal familiar themes in strategies to address non adherence: social support (DiMatteo, 2004); simplification of treatment regimes (Tsai, 2009; Gupta et al, 2009); multidisciplinary efforts at patient support and education and structural support such as patient reminders, more frequent clinic visits or telephone phone calls from staff (Handley et al 2006). However, few significantly affected long term clinical outcomes (Kripalani et al 2007; McDonald et al, 2002)
Therefore the aim of this review is to better understand the strengths and limitations of a patient centred approach for improving medication adherence in patients with glaucoma and identify those interventions that are most effective.
Search Strategy
A thorough search of the literature was performed in order to identify available literature relating to the effect of patient centred interventions which improved medication adherence with individuals diagnosed with glaucoma.
Inclusion Criteria
Study type
· Randomised Controlled Trials (RCT)
· Experimental design
· Non-experimental design
· Controlled Trials
· Peer-reviewed literature research
· Phenomenological
Exclusion Criteria
· Studies that do not stipulate the patients condition
· Studies that did not focus on patient centred or individually tailored interventions
· Non English studies
Participants
· Adults
Outcomes
The primary outcome measures were improved adherence. However all studies with various primary and secondary outcome measures were included in order to gain a comprehensive picture of the effect of patient centred intervention with this population.
Language of population
English Language - 2000 to 2010
Search terms
A thorough search of electronic databases and journals was implored using the keywords:
Condition
· Glaucoma
· Chronic open-angle glaucoma (GOAG)
· Primary open angle glaucoma (POAG)
Intervention
· Patient centred
· Individualised
· Tailored
· Multifaceted
· Psychological
· Group based
Outcomes
· Improved adherence
· Improved compliance
· control of IOP
Databases/Resources Searched
A literature search of studies published between 2000 and 2010 was performed. Databases and search engines used included: OVID Medline, Psycinfo, PsycArticles, AMED, Cochrane Library, Web of Knowledge, and Google Scholar.
Due to time restraints only electronic journals were appraised: Acta Ophthalmologica, International Journal of Circumpolar Health, Clinical Ophthalmology, Eye, Journal of The American Academy of Ophthalmology, Clinical and Experimental Ophthalmology.
Ancestral searching of reference lists to identify all relevant empirical studies also took place.
Source of Search Results
The table below is formed of three columns and five rows.
Study Design/Methodology / Number of Studies Located / SourcesRandomised Controlled Trial / 1 / OVID Medline, PsychInfo,
Web of Knowledge, ASSIA
Non-experimental / 5 / ''
Expert opinion / 2 / ''
Qualitative Study / 1 / ''
Critical Appraisal
Nine studies were identified for appraisal, Cook et al 2010; Hahn 2009; Chen et al 2009; Okeke et al 2009; Budenz 2009; Lunnela et al 2009; Lacey et al 2009; Hoevenaars et al 2008; Friedman et al 2008. (Appendix 1)
Study purpose
These studies all shared a common purpose to examine if a person centred, individualised approach to intervention improved medical adherence with patients diagnosed with COAG. However, the studies were delivered by a variety of professionals, conducted in different settings, using multifaceted interventions.
Friedman et al (2008) investigated patient’s health beliefs and other factors which contribute to improved patient adherence. A ‘glaucoma educator’ was used by Cook et al (2010) to evaluate motivational interviewing (MI), a counseling style focused on exploration and resolution of patients ambivalence. Haln, (2009) discussed the effectiveness of a communication style based on the patient’s stage of readiness to adopt adherent practices, a theme also discussed by Lunnela et al (2010) and Lacey et al (2009). Using results from a questionnaire Lunnela et al (2009) aimed to develop effective interventions to improve adherence a method also adopted by Hoevenaars et al (2008).
Through a literature search Budenz (2009) applied learning from adherence interventions in other chronic diseases to non adherence in glaucoma therapies. Whilst Chen et al (2009) compared patients understanding of glaucoma. In the only RCT Okeke et al (2009) assessed the impact of intervention to improve adherence with topical once daily therapy for glaucoma. Lastly, using qualitative methods to explore potential methods to improve adherence Lacey et al (2009) obtained narratives from participants who described satisfying and dissatisfying therapy experiences.
Literature Review
All nine studies provided detailed discussions on the background to each study/paper, succeeded in aggregating relevant information (previous research etc.), and commented on the clinical importance of the subject. Lacey et al (2009) and Friedman et al (2008) were particularly noteworthy by identifying and addressing gaps in current research. For example the paucity of qualitative research, difficulty in determining which components of multifaceted interventions are most effective, small sample sizes, inadequate racial or ethnic variation and scarcity of comprehensive multifaceted interventions.
Study Design
Using a phenomenology approach Lacey et al (2009) sought to capture patient’s subjective experiences with glaucoma therapy. Five of the authors chose a non experimental design (Hoevenaars et al 2008, Friedman et al, 2008, Chen et al, 2009, Cook et al, 2010, and Lunnela et al, 2010). Only one of the studies employed an RCT design (Okeke et al, 2009). Whilst Hahn (2009) and Budenz (2009) conducted literature reviews and evaluated outcomes.
Both Hoevenaars et al (2008) and Lunnela et al (2010) undertook a cross-sectional study which provides a "snapshot" of the frequency and characteristics of a disease, useful in assessing the prevalence of acute or chronic conditions in a population. However, since exposure and disease status are measured at the same point in time, it may not be possible to distinguish whether the exposure preceeded or followed the disease, and thus cause and effect relationships are not certain.
Friedman et al (2008) used retrospective database and chart reviews which can provide insight into the implementation of new therapies in clini¬cal settings (Sullivan et al, 2005). Both Chen et al (2009) and Cook et al (2010) adopted randomised designs.
Sampling
The sample size, method of sampling and number in each group varied among the studies (12 – 301). According to Aveyard (2007) researchers should demonstrate how they determined the sample size, also known as power calculation (Greenhalgh 1997; Polgar and Thomas 2000) and should be clearly documented in the paper, only Okeke et al (2009) reported doing so. The majority of studies recruited participants from ophthalmology departments with the exception of Chen et al (2009) who used a glaucoma specialist clinic and the Shanghai Glaucoma Club (Est.10 years).
Lunnela et al (2010), Cook et al (2010), Okeke et al (2009) and Lacey et al (2009) provided information regarding participant recruitment and inclusion and exclusion criteria; Friedman et al (2008) referenced previously published study methodology as did Hoevenaars et al (2008). Only Chen et al (2009) did not provide inclusion and exclusion criteria. (not applicable to Budenz (2009) and Hahn (2009).
Okeke et al (2009), Hoevenaars et al (2008) and Friedman et al (2008) incorporated the use of multi site trials increasing sample size and improving the external validity of the study (Polgar and Thomas 2000). According to Aveyard (2007) qualitative samples are often small and this was recognised by Lacey et al (2009) who recruited twenty four (randomly selected) participants.
Ethical Approval
All but one author, Chen et al (2009) provided details on obtaining ethical approval from committees and informed consent from participants, thus reassuring the reader that research was conducted in accordance with accepted community principles.
Intervention/Methods
Over an eight month period Okeke et al (2009) assessed a multifaceted intervention administered by study staff, (without physician input) involving, a ten minute education video stressing the importance of regular drop taking, structured discussion with the study coordinator, use of a diary, reminder telephone calls and administration of a questionnaire about drop taking behaviour. A questionnaire was adopted by Lunnela et al (2010) who investigated topics such as patient adherence, perceived support from clinicians, consequences of treatment and health beliefs, data was collected over fifteen months. During a three month period Hoevenaars et al (2008) also utilised a questionnaire to gauge if increased knowledge improved patient compliance with therapy, as did Chen et al (2009) who used group based interventions to compare compliance, life style, habits and knowledge of glaucoma with an intervention and control group.
Lacey et al (2009) used information gathered from focus groups to inform ten, one-to-one, home based, semi-structured in depth interviews. A structured interview addressing adherence, experiences with medication, communication with physician, and health beliefs was administered to surveyed patients by Friedman et al (2008). Cook et al (2010) evaluated the effectiveness of motivational interviewing, participants assigned to the glaucoma educator received three one to one meetings and three phone calls, literature was also provided to reinforce learning.
Using peer-reviewed research both Budenz, (2009) and Hahn (2009) demonstrated the barriers to adherence and discussed effective interventions.
Data Analysis
Analysis methods and results varied in the studies reviewed. All studies stated how statistical analysis of their data was carried out. A variety of parametric and non-parametric statistical tests were used to determine statistically significant differences pre and post-test intervention.
Lunnela et al (2010) and Cook et al (2010) report using SPSS software to analysis data as did Chen et al (2009) who described using the Wilcoxon and Mann-Whitney U-test (non parametric tests) to confirm statistical differences. To explain the effect of multiple variables (eight in total) Friedman et al (2009) used the multivariate model as did Okeke et al (2009), who also reported using Fisher exact test and Student t test to compare patient-level characteristics. A Pearson chi-squared test was used by Hoevenaars et al (2008), whilst Lacey et al (2009) used ‘Framework’ analysis and NVIVO Software to check data reliability. Developed by researchers at the UK National Centre for Social Research this approach develops a hierarchical thematic framework that is used to classify and organise data according to key themes, concepts and emergent categories (Gibbs, 2010).
Outcome measures
The table below is formed of two columns and eight rows.
Study / Outcome measuresFriedman et al 2008) / Medication possession ration (MPR) - the ratio of days of supply of medication dispensed divided by the days between pharmacy fulfillments.
Hoevenaars et al (2008) / Self administered questionnaire
Okeke et al (2009) / Change in drop use adherence determined by a dosing aid
Lower IOP
Lunnela et al (2010) / Adherence Instrument (ACDI) Kyngas (2000) and self administered questionnaire
Chen et al (2009) / Questionnaire, not documented if self administered
Cook et al (2010) / Medication Event Monitoring System (MEMS) caps – electronic device that records the time and date a pill bottle is opened.
Lacey et al (2009) / Member checking: including extracts of text from the interviews the authors’ allow us to hear the voices of the participants; this is a very powerful way of maintaining credibility, believability and truthfulness.
Results