QUALITY OF LIFE IN PATIENTS WITH ATRIAL FIBRILLATION

ATRIAL FIBRILLATION 0733-8651/96 $0.00 + .20

QUALITY OF LIFE IN PATIENTS WITH ATRIAL FIBRILLATION

Louise S. Jenkins, RN, PhD, and Rosemary S. Bubien, RN, MSN

In the current era of cost containment, shrinking resources, and emphasis on quantifiable outcomes, the word quality is widely used. As an abstract concept, quality is subjectively perceived, making definition elu- sive. When used in the term quality of life, the challenges multiply, particularly when considering health-related quality of life. This challenge is captured in one view of quality of life research as trying to do the impossible by defining the undefinable and observing the unobser~able.~~

Of necessity, the focus in early phases of studying the impact of a particular treatment for a condition inevitably rests on mortality- does the patient live or die? As mortality figures improve, competing treatment strategies for a condition emerge. As these strategies are tested, the opportunity presents to expand the focus beyond life to the actual quality of that life. The challenges of the continuum of care for a particular condition shift from treating the patients first to live, then to living longer, then to living well.

For patients, quality of life is always of prime concern. In the best of all worlds and, it is hoped, as frequently as possible, quality of life is what the individual says it is. Be- cause a critical attribute in defining quality of life is individual perception, it is a subjective phenomenon. Quantification then must rely on information reflecting the perspective of

the individual and come directly from that person; in the case of health-related quality of life, that person is the patient. This self- report can be obtained in a variety of ways that are valid, ranging from verbal responses to open-ended questions to responses to questions or items on instruments specifically designed to measure quality of life.

When related to health, quality of life seeks to encompass the impact of a condition or illness on aspects of one’s life. The aspects of quality of life considered vary and are typically referred to as dimensions. Because many aspects of one’s life contribute to its quality, the trend toward selecting several dimensions (i.e., a multidimensional approach), for con- sideration in a study is increasingly evident.

As is seen in the research reviewed in this article, there is a broad range of how quality of life can be conceptualized. Interestingly the majority of reports claiming to have measured quality of life do not define the term. Likewise, having the term quaIity of life in the title or body of a manuscript does not necessarily mean that what the reader be- lieves is quality of life is addressed.

QUALITY OF LIFE IN PATIENTS WITH ATRIAL FIBRILLATION

Atrial fibrillation is the most frequently oc- curring cardiac rhythm disturbance with an

From the Department of Acute and Long-Term Care, School of Nursing, University of Maryland, Baltimore, Maryland (LSJ); and the Arrhythmia Section, Department of Medicine, Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, Alabama

CARDIOLOGY CLINICS

VOLUME 14 - NUMBER 4 NOVEMBER 1996 597

598 JENKINS & BUBIEN

incidence of approximately 2% of the general population and 5% in adults over 60 years of age. Although not inherently life-threatening, the presence of atrial fibrillation doubles all- cause mortalityIy and is responsible for more than 1 million hospital admissions each year, which is much more than for any other cardiac arrh~thmia.~ Despite the prevalence of atrial fibrillation in clinical practice, there is a paucity of published studies that have included evaluation of aspects of quality of life in the variables considered in the care of these patients.

Until recently, atrial fibrillation has not received nearly as much attention from a research perspective as ventricular arrhythmias. The majority of published studies have focused on traditional variables such as mor- bidity and mortality. Consequently the perspective of the patient has largely been undocumented, although the importance of this perspective is increasingly acknowledged in health care literature and clinical studies.15 As seen in the information that follows, what is known about quality of life in patients with atrial fibrillation has been documented pri- marily from the perspectives of highly symptomatic patients intolerant of or refractory to standard antiarrhythmic therapy and thus referred to tertiary sites for definitive therapy, such as ablation of the atrioventricular node or junction. There are no studies found in the literature that inform about quality of life in the more typical, minimally symptomatic patients responsive to antiarrhythmic therapy.

Search of the literature yielded eight published studies including what might be con- strued as considering at least one aspect, or dimension, of quality of life. Summaries of these studies related to quality of life and results appear in chronologic order in Table 1. Although they span the continuum of so- phistication in the approaches taken to quantifying patient perspectives on quality of life as well as rigor, three distinct approaches are evident: patient interview (two studies), focus on self-reported symptoms (three studies), and multidimensional assessment (three studies) of various aspects of quality of life.

PATIENT INTERVIEW

Interviewing patients to obtain their perspectives can be carried out to obtain various types of data, depending on the types of questions asked. At the most rudimentary

level, quality of life is not measured but inferred from patient responses to interview questions about aspects of their life. Two studies reviewed are of this type.

Focusing on long-term follow-up of patients with supraventricular arrhythmias after treatment with ablation (direct current), a group at University of California, San Fran- cisco, studied 49 patients, 29 of whom had atrial fibrillation or flutter.26 During follow- up interviews with 42 of the 47 surviving patients, 83% reported improved activity level. It is not clear when this interview took place in follow-up, which was a minimum of 12 months (M = 41+23 months). It was noted that the percentage of patients indicat- ing improvement in activity level was significantly ( P < .001) lower in patients with preexisting heart disease than those without. Although this study does not measure quality of life as such, the report of activity level clearly addresses one dimension of quality of life from the patient’s perspective. It is mentioned that patients reported symptoms in the follow-up interview. Symptoms are not reported in a systematic manner, but it was noted that palpitations were reported by nearly one fourth of patients postablation.

In further study from the San Francisco group, follow-up interviews were conducted in which patients who underwent either direct current or radiofrequency ablation gave “a subjective assessment of improvement and quality of life.”25 Of the 54 patients undergoing radiofrequency ablation, 81% had atrial fibrillation or flutter; 59% of those undergoing direct current ablation had atrial fibrillation or flutter. All patients were followed for a minimum of 12 (M = 24k8.4) months postablation. Regardless of technique, the percentage of patients reporting their condition as improved was greater than 80%.

In both of these studies, similar issues exist. The exact questions used in the interview to elicit patient responses related to quality of life are not specified, and improved functioning and improved condition are clearly general constructs. Who administered the standard questionnaire used in the interview? If the interviews were conducted by caregivers, patients may be more likely to tell those pro- viding treatment they were improved. Were these responses chosen from multiple possible responses by the patient, or, as would seem more probable in an interview format, were interview questions open-ended? If the latter were the case, the method used in cate-

QUALITY OF LIFE IN PATIENTS WITH ATRIAL FIBRILLATION 599

Table 1. SUMMARY OF QUALITY OF LIFE ASPECTS OF STUDIES IN PATIENTS HAVING ATRIAL FIBRILLATION

Study Quality of Life Measure(s) Quality of Life Results

Kay et al, 1988*O Design: Descriptive Subjects: N = 12, Paroxysmal atrial

Anderson et al, 1989’ Design: Randomized, double-blind

crossover with placebo Subjects: N = 48, Symptomatic

paroxysmal atrial fibrillation

Rosenqvist et al, 1 99OZ6 Design: Descriptive Subjects: N = 49 (29 with atrial

fibrillation/flutter)

‘Bhandari, et al, 19923 Design: Descriptive, retrospective Subjects: N = 133 (64 with

paroxysmal atrial fibrillation)

fibrillation

Olgin and Scheinman, 1 99325 Design: Descriptive Subjects: N = 54, Supraventricular

arrhythmias (38 [81%] with atrial fibrillation/flutter)

Brignole et al, 1 9945 Design: Two-phase study

1. Randomized to ablation plus pacemaker therapy (n = 12) or pacemaker therapy (n = 11)

Subjects: N = 23, Chronic atrial fibrillation/flutter refractory to drug therapy and/or cardioversion

2. Follow-UP

Hamer et al, 1 994i6 Design: Cross-sectional Subjects: N = 69 (26 with

paroxysmal atrial fibrillation or paroxysmal supraventricular tachycardia)

Bubien et al (in press)’ Design: Descriptive Subjects: N = 159 (22 with atrial

fibrillation)

McMaster Health Index Questionnaire

Psychological General Well-Being

Patient self-report of significant

(Physical Dimension)

Index

symptomatic events

Interview

Symptom self-report

Interview

Self-administered semiquantitative questionnaire-extent to which 5 symptoms were experienced (palpitations, rest dyspnea, effort dyspnea, exercise intolerance, and feeling tired at rest)

Coping Strategies Questionnaire Health Locus of Control Scale Hopkins Symptom Checklist McGill Pain Inventory Psychosocial Adjustment to Illness

State-Trait Anxiety Inventory Scale

Medical Outcomes Study Short Form

Symptom Checklist: Frequency and

Perceived impact-ADL Perceived effects-ADL

Health Survey (SF-36)

Severity (V.3)

Scores on both measures increased significantly from preablation to 6 weeks postablation

The symptoms most predictive of paroxysmal atrial fibrillation were palpitations, dizziness, dyspnea, tachycardia, and diaphoresis

After ablation, 83% of 42 of the subjects reported improved activity level

Over two thirds of symptoms reported were associated with ECG documentation of paroxysmal atrial fibrillation. The five most frequently reported symptoms were tachycardia, palpitations, dyspnea, chest pain, and dizziness

Of those interviewed who were treated with radiofrequency ablation (n = 38), 84% reported improved condition after ablation; of those treated with direct current (n = lo), 80% reported their condition as improved

After 2 weeks, symptoms decreased more in patients receiving ablation. Then, control patients were ablated and all patients followed for 90 days. Improvement in symptoms was accompanied by objective assessment of functional class (NYHA class, exercise duration)

No significant differences found between scores of patients with the two types of arrhythmias. Patients classified as having symptoms that were disruptive were no different as to extent or severity of medical condition. Subjects described as basically well-adjusted

Patients with atrial fibrillation had poorer quality of life at baseline than patients with other arrhythmias. Whereas their quality of life improved at 1 and 6 months afterablation, it was to a lesser extent than patients with other arrhythmias

ADL = Activities of daily living.

gorizing patient responses as improved, un- changed, or worsened condition would be of interest.

Determination of the meaning of patient

responses in these studies is difficult in that patients were followed for varying lengths of time. Although both reports stated that patients were followed for at least a year, the


range of follow-up time was large. Responses from a patient 12 months postablation may be quite different from those obtained at later points in time. Finally, although the term quality of life was used in both reports, no definition of what is meant is offered. The interest in patient perspectives is a notable addition to these reports, but the lack of detail makes it difficult to interpret findings.

SELF-REPORTED SYMPTOMS

In a seminal discussion of symptoms of atrial fibrillation, Bellet2 links symptoms to the severity of cardiac involvement. He lists palpitation, breathlessness, fatigue on exer- tion, precordial oppression, and cough as symptoms. RutledgeZ8 underscores the value of patient self-report in diagnosing atrial fibrillation, particularly when it is paroxysmal and obtaining electrocardiographic confir- mation is a chance occurrence. The advent of transtelephonic monitoring offered an opportunity to relate patient-reported symptoms to the electrocardiogram (ECG). Two studies provide examples of this approach and the value of patient report of symptoms.

A study from the Flecainide Supraventricu- lar Tachycardia Study Group' included patient self-report of symptoms as part of a randomized drug trial for treatment of paroxysmal atrial fibrillation. Symptoms were reported when significant symptomatic events were experienced and validated with transtelephonic monitoring. The 48 patients included in the main study were again predominately male (two thirds) with a mean age of 56 years. Five symptoms were most predictive of attacks of paroxysmal atrial fibrillation (>YO%): palpitations, dizziness, dyspnea, tachycardia, and diaphoresis.

A second report from the Flecainide Supra- ventricular Tachycardia Group3 also included patient report of symptoms in a descriptive study aimed at relating symptoms with epi- sodes of paroxysmal supraventricular tachycardia or atrial fibrillation using transtelephonic monitoring. Record review was used for data collection. Of the 113 patients included in this study, more than half (n = 64) had paroxysmal atrial fibrillation; they were predominately male (two thirds) with a mean age of 57.4 years. The most frequently reported symptoms in this group were tachycardia, palpitations, dyspnea, chest pain, and dizziness. Symptoms reported were validated

by transtelephonic monitoring calls in 69.2% of the total instances. Although retrospective in design, this study provided important knowledge from the subjective perspective of the patient, which related to objective transtelephonic monitoring of the ECG.

In a third investigation, Brignole and col- leagues5 conducted a two-phase study of 23 patients with chronic atrial fibrillation or flutter who were refractory to drug therapy including amiodarone. In the first phase, patients were randomized to receive either atrioventricular junctional ablation and a VVIR pacemaker; the control group received a pacemaker (WIR 70-130) only. At the end of 2 weeks, all patients were evaluated. In phase two (follow-up), control patients also were ablated.

Quality of life was considered by a self- administered semiquantitative questionnaire. Pa- tients used an ll-point (ranging from 0 = absence to 10 = maximum) to report the extent to which they had experienced palpitations, rest dyspnea, effort dyspnea, exercise intolerance, and feeling fatigued at rest. Of the 23 patients in the study, 52% were males, and the mean age was 67 years. Level of function was estimated using the New York Heart Association (NYHA) functional classes; the mean at baseline was 2.3. At day 15, patients who had ablation as well as the pacemaker implantation had significantly lower scores for the symptoms of palpitations and effort dyspnea. At 90 days, improvement con- tinued for all patients and was associated with improved functional capacity as measured by NYHA class and exercise duration via treadmill.5

MULTIDIMENSIONAL ASSESSMENT OF QUALITY OF LIFE

With quallty of life being individually perceived and meaning varying across individuals, one useful approach has been to consider a multidimensional approach. In the earliest days of quality of life research, the dimensions of interest were societal in focus-for example, income levels of populations. In contrast, when related to health, quality of life is usually conceptualized from the perspective of the ind i~ idua l .~~ A working definition used at the National Heart, Lung, and Blood Institute focuses on an individual's total well-being, including psychological, social, and physical health status. This definition


flows from the World Health Organization’s definition of health as well as early quality of life research.” In application, this typically means recognition that important aspects to consider can be drawn from various aspects of one’s life. The challenge is to identify aspects or dimensions that are meaningful for the patient group being considered and then to select appropriate measures.

In a study of patients with paroxysmal supraventricular tachycardia and paroxysmal atrial fibrillation, Hamer and colleagues16 also pointed to the paucity of information about patient perceptions of living with supraventricular arrhythmias. They compared patients with these two types of arrhythmias using a battery of several quality of life instruments with the stated aim to ”. . . assess functional disability and coping strategies.”

Of the 69 patients participating, 26 had paroxysmal atrial fibrillation. Ten of the 26 (38%) were women; the mean years of symptoms was 13 & 12 and mean age was 60 k 14 years. Although the larger group of patients with paroxysmal supraventricular tachycardia (n = 43) was younger with a mean age of 49 & 14 years, a greater percentage were women (50%), and the years of symptoms were greater with a mean of 18 * 13 years.

The quality of life battery was made up of six instruments. The Health Locus of Control Scale includes items to which respondents indicate the extent to which their health de- pends on others, chance, or internal The Psychosocial Adjustment to Illness Scale considers five dimensions: health care orien- tation, vocational, domestic environment, social environment, and sexual functioning.’O The State-Trait Anxiety measures two types of anxiety: the more stable trait or typical and the current status or The McGill Pain Inventory includes three dimensions: sensory, affective, and evaluative.22 The Coping Strategies Questionnaire considers several approaches to coping with pain: di- verting attention, catastrophizing, reinterpre- tation, coping self-statements, ignoring, pray- ing or hoping, and behavioral increase.27 Finally, the Hopkins Symptom Checklist claims to measure emotional distress and psy- chopathology.”

No significant differences were found between the scores of patients with the two types of arrhythmias on any measures. The investigators summarize the sample studied as basically well-udjusted.’6 Although the report does not link directly back to quality of life,

they conclude that interventions aimed at stress reduction and development of improved coping skills may be of benefit for this patient group.

This study is important in demonstrating the feasibility of using an extensive battery of instruments to measure selected dimensions of quality of life and profiles some information about patients living with paroxysmal supraventricular arrhythmias. A major limita- tion is the cross-sectional design. All patients had been living with symptoms for many years and were under care, but modes of treatment were not reported. Interestingly, transtelephonic monitoring confirmed that 97% of patients were in sinus rhythm when they completed the quality of life battery of instruments.

Longitudinal studies offer the opportunity to consider how quality of life varies before and at selected points after therapy is insti- tuted. Two reports from the University of Alabama at Birmingham demonstrate this as well as another way that multidimensional approaches can be conceptualized: considering subjective perspectives of the individual with respect to relevant objective data. For example, scores on patient perceptions of what one is able to do (e.g., how far can one walk) can be correlated with a measure of function, such as exercise capacity by treadmill test.

The earliest of these studies systematically evaluated rate-adaptive pacing therapy on physical function, well-being, and symptoms in 12 patients with paroxysmal atrial fibrillation.20 Patients were treated with atrioventricular junction ablation and subsequent implantation of either an activity-sensing or minute-ventilation-sensing single-chamber, rate-adaptive pacemaker.

The investigators chose measures of aspects of quality of life that had been used in other studies. The definition of quality of life guiding this work was from Wenger and col- league~;~ ”total well being-psychosocial as well as physical,” who broadly consider three aspects or dimensions of quality of life: functional capacity, perceptions, and symptoms.

The psychosocial dimension of quality of life was measured with the Psychological General Well-Being Index.I2 The physical dimension was measured by the Physical Di- mension portion of the McMaster Health Index Que~tionnaire.~ Both of these paper- and-pencil measures were administered a day before ablation and again 6 weeks later. In


addition to this subjective assessment of physical function, objective assessment was accomplished by way of treadmill testing preablation and 6 weeks later.

Subjects (8 men and 4 women) had a mean age of 67 years and had lived with paroxysmal atrial fibrillation a mean of 9 years. Statis- tically significant increases in scores between data collection point were found on both Psy- chological General Well-Being Index (P =

.001) and the Physical Dimension of the McMaster measure (P = .002). Concurrently, there was a significant increase in exercise duration in the treadmill testing (P = .03). The correlation between the increase in Physi- cal Dimension scores and exercise duration by treadmill was robust ( r = 0.70, P = .03).

Some patients from this study were also included in two abstracts reporting findings related to quality of life with pacing. Using the same measures as previously, both of these reports demonstrate statistically significant improvement in quality of life baseline and 1 month after pacemaker insertion; also, between 1 and 6 months postprocedure, the improved scores were sustained.8, 21

More recently, in a study of 159 patients with various types of arrhythmias being treated by radiofrequency catheter ablation, the Wenger definition was again used to choose measures of health-related quality of life preablation and at 1 and 6 months p~stablation.~, 35 A battery of four quality of life measures was used at each of the data collection points. The Medical Outcomes Study Short Form Health Survey (SF-36) as- sesses eight dimensions of health status and well-being: (1) Physical Functioning; (2) Role Limitations-Physical; (3) Bodily Pain; (4) General Health; (5) Vitality; (6) Social Func- tioning; (7) Role Limitations-Emotional; and (8) Mental Health.34 The Symptom Checklist: Frequency and Severity was used to allow patients to report systematically how often they experience arrhythmia-related symptoms as well as their perceived severity.6 Two investigator-developed, brief instruments were also included: Perceived Impact of the Arrhythmia and Effects of Arrhythmias on Activities of Daily Living.

Twenty-two of the subjects in this study had atrial fibrillation. Nearly three fourths (73%) of these were female; the mean age was 62 t 12 years. Mean number of years living with symptoms of the arrhythmias was 8.5 t 14.5. Patients with atrial fibrillation had the highest mean age of five arrhythmias in-

cluded and took the most medications with a mean of 4.8 2 1.7.

At baseline, patients with atrial fibrillation had lower scores on the SF-36 than did patients with any other arrhythmia mechanism for half of the dimensions considered (Vital- ity, Role Limitations-Physical, Role Limita- tions-Emotional, and Social Functioning) and the highest levels of Symptom Frequency and Symptom Severity. SF-36 scores improved significantly ( P 5 .05) for all dimensions except for Mental Health and General Health. Both symptom frequency and severity decreased significantly (P < .01) in patients with atrial fibrillation as well as for patients with all types of arrhythmia mecha- nisms except ventricular tachycardia. The greatest improvement in scores was between baseline and 1 month postablation; scores at 1 and 6 months postablation remained generally stable.

The Perceived Impact of the Arrhythmia, using a format identical to the physical role function scale of the SF-36, measured the extent to which subjects perceive their arrhythmia as interfering with daily activities. The effect of the arrhythmia on performance of physical, social, family, travel/vacation, driv- ing, and medical visits was quantified via the Activities of Daily Living instrument. Overall, patients with atrial fibrillation experienced high levels of impairment and despite significant improvement after ablation therapy, a greater degree of impairment was evident compared to the other groups undergoing ab- lative therapy.

Although there is a great deal of information from this study, and as seen in the earlier discussion of the two 26 from the University of California, San Francisco, group, a major challenge to interpreting the findings is the variability in the time at which postablation data were collected. The range for collection of 1-month data was from 4 to 8 weeks postablation. The report indicates, however, that 6-month data were actually collected over a range of 24 to 70 weeks.

It is important to note that yet another level of patient self-report of symptoms6 was used in this study. By completing a symptom checklist, patients provided data on whether they had experienced a list of symptoms, the frequency of occurrence, and the severity of the symptoms. This approach offers a more systematic method than that described by Brignole and colleagues5 and has usefulness from a clinical as well as research perspective.


STUDIES IN PROGRESS

Ablate and Pace Registry (APT)

This study is a prospective, multisite, registry study (sponsored by Medtronic, Inc., Minneapolis, MN) of 160 patients with symptomatic atrial fibrillation treated with atrioventricular junctional ablation followed by implantation of a single-chamber or dual- chamber rate-adaptive pacing system as indi- cated. Quality of life is among the variables being systematically studied with data collection at baseline and 3 and 12 months postprocedure.

In this study, quality of life is defined as individually perceived, dynamic, multidimensional, and quantifiable by individual self-report of patients. A tiered approach to assessing quality of life is being used that incorporates several instruments. At the most global level, the Health Status Question- naire,I7 version 2.0, which is the Health Out- comes Institute analogue of the Medical Out- comes Study Short Form (SF-36), considers eight dimensions of quality of life: (1) Health Perception; (2) Physical Functioning; (3) Role Limitations-Physical; (4) Role Limitations- Emotional; (5) Social Functioning; (6) Mental Health; (7) Bodily Pain; and (8) Energy/Fa- tigue.

Narrowing the focus to allow for comparison of scores with those of other patients with various cardiac diseases, the Quality of Life Index-Cardiac Version IIP3 considers four dimensions of quality of life: (1) Health and Functioning; (2) Socioeconomic; (3) Psycho- logical/Spiritual; and (4) Family. An important characteristic of this instrument is that respondents first indicate their satisfaction with items reflecting various aspects of quality of life. Then, respondents indicate the importance of each of these items to them as individuals. The scoring schema adjusts satisfaction scores by importance with high levels of satisfaction with things important to the individual reflecting the highest levels of quality of life.

The instrument included that is specific to patients with atrial fibrillation is the Symp- tom Checklist: Frequency and Severity.6 This is a checklist of 16 symptoms frequently reported in patients with atrial fibrillation.

A preliminary reportl8 of the baseline scores from this study describes poor quality of life before treatment. Because patients en- rolled in this study are symptomatic, this

finding is not unexpected and does document a profile of quality of life in the largest sample of patients with atrial fibrillation to date. The baseline data provide a point of reference for posttreatment comparisons as data are being collected 3 and 12 months postablation and pacemaker implantation. Additionally, this study is important for demonstrating the feasibility of obtaining a comprehensive quality of life assessment in this patient group, even when highly symptomatic.

Atrial Fibrillation Follow-Up: Investigation of Rhythm Management (AFFIRM)

Although studies initiated or supported by the National Heart, Lung, and Blood Institute of the National Institutes of Health have included aspects of health-related quality of life in studies since the mid-1970~:~ the first to be conducted with patients with atrial fibrillation is now in progress. AFFIRM is a prospective, randomized clinical trial comparing rate versus rhythm control, both with anticoagula- tion, in patients with documented atrial fibrillation who are 65 years old or older or younger than 65 years at risk for either stroke or mortality.

Quality of life is a secondary endpoint in this study and is assessed using the same definition as the APT study described previously; the quality of life assessment is highly similar. At the most global level, subjects rate their health by choosing one of five options ranging from excellent to poor. The Ladder of Life is being used to allow patients to rate their life currently, 5 years ago, and 5 years in the future using a 10- point scale ranging from worst possible to best possible. The Medical Outcomes Study Short Form Health Survey (SF-36)34 is being used to consider the eight dimensions identified in the description of the Bubien and co-workers7 study. As previously described, the Quality of Life Index-Cardiac Version 1113 and the Symptom Checklist: Frequency and Severity6 are also being used.

Data are being collected at baseline (preran- domization) and at intervals during the first year of follow-up as well as annually. AF- FIRM has numerous goals; the knowledge gained about quality of life from this large study will be an important addition to the science as well as in implications for clinical practice. Because it is a large-scale study and


not limited to highly symptomatic patients, it may provide the first knowledge of quality of life in the most frequently seen patients with atrial fibrillation.

DISCUSSION

As can be seen from the information pre- sented from the studies reviewed, much has yet to be learned about quality of life in patients with atrial fibrillation. Although using various designs, the studies have some com- monalities. Generally, sample sizes are small and limited to symptomatic patients who may be refractory to traditional pharmaco- therapy. An exception to this may be the cross-sectional study"j of patients with supraventricular arrhythmias in which information about sypptoms is not detailed.

All but one of the studies were prospective. Most investigators have incorporated multiple data collection points into their designs, which produce knowledge about changes in quality of life as treatment is carried out and allow for tracking of changes over time. In the studies in which a multidimensional assessment was used, various instruments were used. Although this state of affairs produces interesting data, one can easily see how impossible it can be to compare quality of life across studies given the wide variation in instruments selected. It is clear in the studies in progress that consistency of instruments selected allows for some comparison of results across studies. There is also a place for instruments tailored to the specific population being studied, and, as seen, investigator- developed instruments can be a complement to more widely used instruments designed for broader applications.

Selection of instruments for a study is a challenge. Among the several guiding princi- ples that one might use is that the instru-

ments chosen for inclusion in a study have acceptable evidence for reliability and validity. Indeed, that seems to be the case for nearly all of the instruments used, but that evidence is not reported. Because respondents to instruments are different in each study in which instruments are used, it is recommended that evidence for reliability and validity for instruments be calculated and reported each time.33 Because some may view quality of life as a "soft" construct, rigor is imperative, and attention must be given to these psychometric properties of measures as well as to design of quality of life studies.

There are many criteria by which one might judge the quality of quality of life studies. A review14 of quality of life instruments used some extensive parameters, such as (1) having a conceptual definition of quality of life, (2) identifying what dimensions of quality of life were being measured, (3) giving reasons for why instruments were chosen, (4) aggre- gating scores from multiple instruments into one summary score, (5) asking patients to give an overall rating of quality of life, (6) distinguishing overall quality of life from health-related quality of life, (7) asking patients to add perspectives beyond those re- quested, and (8) asking patients to indicate which items are of greatest importance to them as individuals.

Although one may not agree with all these criteria, a question is: If the studies reviewed were considered with regard to these criteria, how would they fare? The results are found in Table 2. All studies received met at least one criteria. It is disappointing to note that only two studies state their conceptual definition. Specific aspects or dimensions of quality of life were addressed in all but two studies, although only two reports gave insight into why instruments were chosen.

No study met the criteria of one composite score. This criteria is not one others mention

Table 2. ANALYSIS OF QUALITY OF LIFE IN STUDIES REVIEWED USING GILL AND FEINSTEIN'Sq4 CRITERIA

Investigators

Overall Conceptual Targeted Reasons Composite Versus Separate Definition Domains Chosen Score Health Rating Supplement Importance

Kay et alno Anderson et all Rosenqvist et atz6 Bhandari et a13 Olgin and ScheinmanZ5 Brignole et a15 Hamer et all6 Bubien et a17

J J J J J

J ? J

J ? J j J

J J J J


and may be the one most likely to be ques- tioned. The idea that one can aggregate scores of various quality of life dimensions into a summary score is useful from a statistical perspective but seems inconsistent with a holistic approach in which the whole of an individual is always greater than the sum of its parts. Three studies clearly focused on dimensions of health-related quality of life versus an overall, global assessment. Some might argue that the symptom-reporting approach is illness-related versus health. Others accept the symptom experience as a specific dimension of health-related quality of life. If the two studies using interviews gathered their data using open-ended questions, they provided opportunities for patients to provide a separate rating beyond responses to items on instruments. In fact, because they did not use "items," that was the only assessment made. Also, this approach meets the criterion that patients were able to supplement their responses to items with additional information.

No study included the opportunity for the patient to indicate what things are individually most important. Without including this opportunity for patients, investigators make assumptions about what is important for a group of people and may seriously, although unintentionally, error and bias what can be inferred about quality of life in a particular study. If satisfied with things not important to an individual, is that really quality of life? A step has been taken toward meeting this criterion in the two studies in progress in which importance of various aspects of an individual's life is a part of one of the instruments being used.I3

Criteria developers reviewed a sample of studies published through 1989 that had quality of life in the title. Of the 75 articles reviewed, findings included that only 15% of the investigators defined quality of life, whereas nearly half (46%) did say what dimensions they were measuring. Just Over one third stated why particular instruments were selected to measure quality of life. More than 30% converted scores obtained into a composite score; 17% included a global rating of quality of life, and only 8.5% integrated the importance criteria discussed earlier. No report distinguished global quality of life from health-related quality of life, which is not at all surprising given that only 15% defined quality of life. Although the studies reviewed were not confined to those with cardiac pa-

tients, these findings are not inconsistent with the information in Table 2.14

Although the authors propose somewhat different criteria, those discussed provide a framework for comparison. From the collec- tive wisdom found in the literature as well as in involvement in studies in which quality of life is a key component, the authors propose that the following criteria might be useful in evaluating the quality of studies claiming to quantify health-related quality of life: (1) defining quality of life for the particular pur- pose of the study; (2) considering multiple dimensions and, at minimum, using a biopsy- chosocial approach; (3) specifying the ratio- nale for the choice of measures selected; (4) using at least one measure that is general in focus in that it considers quality of life from a broad perspective-this type of measure (e.g., the Medical Outcomes Study Short Form 36 [SF-36]34) is likely to have been used in other studies and populations and offers an opportunity to compare scores across studies; (5) using at least one measure that is specific to the population of interest (e.g., the Symptom Checklist: Frequency and Severity6 is designed for use with patients with atrial fibrillation); (6) selecting measures with evidence for reliability and validity and reporting appropriately; (7) collecting data at several points in the treatment process to consider any changes over time; and (8) having all assessments done from the perspective of the individual patient.

The state-of-the-art in quality of life in patients with atrial fibrillation is beginning knowledge and informs only about highly symptomatic patients. Rigorous, yet practical approaches are needed to allow for a comprehensive understanding of quality of life in this population. That knowledge is important for several reasons, including (1) quantifying the impact of various treatments; (2) helping to develop profiles of quality of life in both mildly and severely symptomatic patients; (3) identifying predictors of quality of life; (4) examining the relationships between quality of life, adherence to treatment, mortality, and other variables of interest; and (5) assisting in developing and testing interventions that might complement medical therapy in im- proving outcomes of treatment from the perspective of the individual patient.

ACKNOWLEDGMENT The authors acknowledge with appreciation the assis-

tance of Jean Gaynor in the preparation of this manuscript.


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University of Maryland School of Nursing, Suite 404

655 West Lombard Street Baltimore, MD 21201-1579

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QUALITY OF LIFE IN PATIENTS WITH ATRIAL FIBRILLATION