In managing any chronic condition, clinicians

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1 VALIDITY AND CLINICAL RELEVANCE OF 2 NEW QUALITY-OF-LIFE INSTRUMENTS FOR CHILDREN AND ADULTS WITH EPILEPSY * Ann M. E. Bye, MBBS, FRACP, Mark Sabaz, BSc, Frank Gilliam, MD, MPH, and Paul Courter, BA ABSTRACT This article summarizes 2 presentations made at a Special Interest Group session ( Quality of Life and Outcomes: New QOL Instruments for Children and Adults with Epilepsy ) of the 56th Annual American Epilepsy Society meeting. One presenter described his group s recent evaluation of the content validity of various health-related quality-of-life (HRQOL) measures and the subsequent development of a 20-item patient-oriented outcomes assessment tool called the Epilepsy Foundation of America (EFA) Concerns Index. The EFA Concerns Index has now been validated as an accurate gauge of patient-oriented concerns and it has recently been compared with other HRQOL instruments to document postsurgical improvement. The other presenters described their efforts in developing and validating an HRQOL that was specific to the pediatric epilepsy population. The psychometric properties and the clinical sensitivity of this new instrument, called the Quality of Life in Childhood Epilepsy Questionnaire, have now been validated in the Australian population and the American validation has been published in abstract form. The instrument has also been used to show that the presence of intellectual deficit independently depresses HRQOL outcomes and that there are syndrome-specific effects of epilepsy on quality of life. As these and similarly improved tools for measuring quality of life in epilepsy are developed, validated, and then applied in clinical research, the clinician s ability to determine which interventions provide the best range of outcomes will improve. (Adv Stud Med. 2003;3(7B):S684-S690) *Based on presentations given by Drs Bye, Sabaz, and Gilliam at a Special Interest Group session of the 56th Annual Meeting of the American Epilepsy Society. Associate Professor, School of Women s and Children s Health, University of New South Wales; and Pediatric Neurologist at Sydney Children s Hospital, Sydney, New South Wales, Australia. Research Assistant, School of Women s and Children s Health, University of New South Wales, Sydney, Australia. Director, Adult Epilepsy Center, Associate Professor, Department of Neurology, Washington University School of Medicine, St Louis, Missouri. Senior Contributing Editor, Johns Hopkins Advanced Studies in Medicine, Seattle, Washington. Address correspondence to: Anne M.E. Bye, MBBS, FRACP, School of Women s and Children s Health, University of New South Wales, Sydney New South Wales 2052, Australia. a.bye@unsw.edu.au. In managing any chronic condition, clinicians need to be alert for trade-offs between treatment benefits and risks. In recent years, this balancing act has come to include assessment of health-related quality of life (HRQOL) before and after the intervention (whether drug, device, surgery, or behavioral/social). This is also the case with epilepsy, where the extensive psychosocial impact of the disease on patients and their families is abundantly clear. Community-based surveys, for example, indicate that having epilepsy produces a variety of occupational and economic disabilities, including being less likely to graduate from high school, get married, or remain employed. 1 The overall impact of S684 Vol. 3 (7B) July 2003

2 epilepsy on these and many other patient or family perceptions of quality of life (QOL) (eg, ability to drive, social relationships, self esteem) even in those in whom seizures are controlled is not in question. 2 However, despite widespread acknowledgement that patients with epilepsy have a worse HRQOL than the general population, much of the research on QOL in this population has been fragmentary and, because of an unstandardized approach, contradictory. 3 While a focus on seizure frequency as the natural outcome of interest in epilepsy is to be expected, and while seizure frequency does indeed correlate with HRQOL, 4,5 only recently have HRQOL tools matured into valid and discrete secondary outcomes in clinical trials. As a sign of this maturation, the principles of HRQOL assessment in clinical trials have recently been outlined to assist researchers. 6,7 A listing of the available epilepsy-specific HRQOL instruments attests to the high interest but also to the potential confusion regarding choices confronting the clinician-researcher as well as the clinician (Table 1). 7 Further validation of these epilepsy HRQOL tools and, even more important, their testing in typical nonresearch clinical settings will be critical in assessing the full risk-tobenefit ratio of new surgical techniques and antiepileptic drug (AED) therapy. For example, in certain benign epilepsy conditions such as idiopathic partial epilepsy with centro-temporal spikes, the risk from the HRQOL-related side effects of AEDs may actually outweigh the potential drug benefits in terms of seizure control. 8 Only a highly refined HRQOL scale will be capable of detecting such subtle but critical alterations in a patient s, a family s, or a child s QOL. Similarly, in assessing surgical outcomes, only proper interpretation of the HRQOL response (eg, using the minimally important difference ) and careful selection of other sophisticated methodologies will help detect the real magnitude of an intervention on an individual s HRQOL. 7,9 In this article, evaluations of 2 epilepsy HRQOL instruments are summarized. These evaluations were recently reported at the Special Interest Group of the American Epilepsy Society (AES) meeting and are indicative of the careful scrutiny that HRQOL instruments require before routine use in research or practice. Frank Gilliam MD, MPH, of Washington University in St Louis, Missouri, studied the content validity of various HRQOL measures by asking his patients what concerned them most about living with epilepsy. This is a fundamental but surprisingly neglected aspect of HRQOL research. In the second presentation, Ann M. E. Bye, MBBS, FRACP, and Mark Sabaz, BSc, focused on the validation of an HRQOL instrument in the pediatric epilepsy population, another understudied but critically important area of epilepsy research. 10 WHAT MATTERS MOST TO PATIENTS? DEVELOPMENT AND APPLICATION OF THE EFA CONCERNS INDEX In the early 1990s, despite major technological advances in epilepsy evaluation (eg, neuroimaging and Table 1. Epilepsy-Specific HRQOL Instruments QUALITY-OF-LIFE ASSESSMENTS " Well-Being and Epilepsy " Liverpool Quality-of-Life Battery " Life-Fulfillment Scale " Impact of Epilepsy Scale " Quality-of-Life Assessment Schedule (QOLAS) " Epilepsy Surgery Inventory (ESI-55) " Quality of Life in Epilepsy Instruments (QOLIE-89, QOLIE-31, QOLIE-10) " Health-Related Quality-of-Life Questionnaire for People with Epilepsy (HQLQ-E) " Epilepsy Foundation of America (EFA) Concerns Index " Quality of Life in Newly Diagnosed Epilepsy Instrument (NEWQOL) QUALITY-OF-LIFE ASSESSMENT OF CHILDREN AND FAMILIES " Child Attitude Toward Illness (CATIS) " Adolescent Stigma Scale " Childhood Illness Scale " Hague Restrictions in Childhood Epilepsy Scale " Quality of Life for Adolescents with Epilepsy (QOLIE-AD-48) " Quality of Life in Childhood Epilepsy Questionnaire (QOLCE) PSYCHOSOCIAL ASSESSMENTS " Washington Psychosocial Inventory (WPSI) " Adolescent Washington Psychosocial Inventory (AWPSI) " Sepulveda Epilepsy Battery " Social Effects of Epilepsy HRQOL = health-related quality of life. Adapted with permission from Cramer et al. Epilepsia. 2002;43: Advanced Studies in Medicine S685

3 digital electroencephalography [EEG]) and epilepsy basic science, only a modest amount of research had been devoted to systematic assessment of outcomes in epilepsy. In particular, little emphasis had been placed on sampling patients in a rigorous quantitative fashion to determine which specific aspects of living with epilepsy or recurrent seizures were most important to them. 11 To help clinicians and researchers become more aware of their patients personal experience of disease, Dr Gilliam s group set out to create a simple tool for measuring patient-centered outcomes. Their goal was to ensure that the outcomes used to evaluate epilepsy treatment success actually captured the key domains of most concern to patients. The resulting 20-item patient-oriented outcome assessment tool, named for the agency that funded this effort with a start-up grant, is called the Epilepsy Foundation of America (EFA) Concerns Index. 12 To generate a complete and appropriate list of patient-centered concerns for the EFA Concerns Index, Gilliam et al asked a consecutive series of 81 adult patients with moderately severe epilepsy (2.3 seizures per month) to list their concerns in order of importance. The 40 men and 41 women ranged in age from 18 to 68 years (mean 38 years) and all were taking at least 1 antiepileptic medication. The patients were left alone with a blank piece of paper (more on request) and given as much time as necessary. Some patients completed the forms at home; family members were allowed to help. The key to this first step in the HRQOL development process was to limit staff input or bias as much as possible. Structured interviews were performed only to confirm or clarify those written patient concerns that were difficult to interpret or classify into domains. In fact, most of the concerns were readily classified, and there was about 90% correlation between investigators in the classification step. However, a few important distinctions in patient concerns were detected in this follow-up. When citing family worry, for example, about half of patients actually meant they were worried about being able to take care of their family while the other half were worried about their family being overly concerned about their situation. The issue of independence was another domain that was subject to varying interpretations, with some patients using the term as a surrogate for driving, but with many others stating, for example, hiking in the woods on their own or going to the mall without their mother. Such nuances in patient-defined outcomes should serve to remind clinicians to listen carefully and to avoid assumptions when talking with patients. Overall, the patient concerns were limited to 24 separate domains. The domains listed by more than 30% of patients were: concerns about driving (64%), independence (54%), employment (51%), social embarrassment (36%), medication dependence (33%), mood/stress (32%), and safety (31%). Other concerns listed by more than 5% of patients, in decreasing frequency of mention, were: medication side effects, recreation, social life, seizure unpredictability, cognitive effects of epilepsy, worry about family, seizure aversion, physician/hospital dependence, enigma of epilepsy, family worry, medical costs, future, and discrimination. The consistency of these concerns was remarkable. In fact, study enrollment was terminated at only 81 patients because of the study stipulation that recruitment end when 30 consecutive patients list no new concerns. Such consistency indicates that patient concerns, although subjective, can indeed become a valuable outcomes measure in clinical trials. Figure 1.What Are Epilepsy Patients Most Concerned About? Adapted with permission from Gilliam et al. Epilepsia. 1997;38: S686 Vol. 3 (7B) July 2003

4 The concerns listed as the most important by most patients in the EFA study were driving, employment, and independence (Figure 1). 12 Many areas of concern identified in this study had not been identified in previous patient-oriented studies 13 and several concerns are still not found in existing HRQOL instruments for epilepsy (eg, QOLIE-89, Liverpool HRQOL model). The authors of the EFA study concluded that patient concerns about their chronic seizures are neither vague nor obscure and that these concerns can actually be monitored before and after treatment as another gauge of treatment efficacy. To construct a practical patient-oriented outcome tool, the researchers went back to about 50 patients to test specific terminology for each domain. The exact phrasing of certain questions proved critical, as, for example, when the patients uniformly expressed no concern over their ability to drive but acknowledged concern over their legal right to drive. The feedback from these small group interviews allowed the researchers to refine a 20-domain list that accurately and succinctly represented the key results of the study just described. In a validation test of this 20-item EFA Concerns Index, Gilliam et al tested the tool alongside another HRQOL instrument, the Epilepsy Surgery Inventory- 55 (ESI-55), in 125 patients undergoing anterior temporal lobectomy (ATL) for refractory epilepsy. 14 These results were compared with those from a clinically similar group of 71 patients who were awaiting the surgery. Those patients who had undergone ATL scored significantly better in 16 of 20 items in the EFA Concerns Index and in 8 of 11 scales of the ESI-55. Interestingly, 2 items that did not improve postsurgically were concern over other people s understanding of epilepsy and concern for the future. Improvements in 4 specific EFA Concerns Index patient concerns mood status, employment, driving, and AED use were statistically associated with changes in related domains in the HRQOL tool. The researchers concluded that the EFA Concerns Index offers a valuable complementary measure to other established HRQOL instruments. Before this test of the EFA Concerns Index, a direct assessment of fundamental patient concerns, such as driving, employment, and independence, had not been previously reported. These results, plus those of other recent studies, 5,15 indicate that patient-centered outcomes and HRQOL will be increasingly valuable in assessing outcomes after surgical or medical inter- Figure 2. QOLCE Scale Development Stage 1 Consult literature & existing questionnaires Qualitative questionnaire to patient families (N=32) Stage 2 Identify and create items/questions Draft survey Stage 3 Assessment by independent panel of epilepsy medical and paramedical personnel (N=8) Stage 4 Creation of 178-item Child Epilepsy Questionnaire: Child Seizure Profile (87 items) Quality of Life in Childhood Epilepsy Questionnaire (91) QOLCE = Quality of Life in Childhood Epilepsy. Table 2. Examples of QOLCE Questionnaire Items NEGATIVE " How often has your child needed more supervision than other children his/her age? " How much of the time do you think your child felt down or depressed? " How often has your child had trouble talking? " How often has your child s epilepsy frightened other people? " How often did your child get angry easily? POSITIVE " How often has your child played freely outside the house like other children his/her age? " How much of the time do you think your child felt happy? " How often has your child s epilepsy improved his/her relations with family members? " How often did your child join in activities with other children? QOLCE = Quality of Life in Childhood Epilepsy. Advanced Studies in Medicine S687

5 vention. Further studies in different populations will be welcome, not only in patients with different types and severities of epilepsy and in pediatric populations, but also in patients from different cultures or countries whose concerns may be surprisingly different. Table 3. Sensitivity of QOLCE to Seizure Severity r P MEASURING QUALITY OF LIFE IN CHILDREN WITH EPILEPSY: VALIDATION OF THE QOLCE Epilepsy in childhood and adolescence is known to affect a wide range of life functions, yet most research on HRQOL in epilepsy has focused on adult populations. Many of the generic HRQOL measures used to assess function, disability, and distress in younger patients (eg, Child Health Questionnaire [CHQ] and Child Behavioral Checklist [CBCL]) 16,17 are relatively insensitive to the specific concerns of children with epilepsy. The few childhood epilepsy-specific tools that are in development are limited in their applicability, confined to a particular domain, or restricted to an age group such as adolescence As described by Dr Bye and Mr Sabaz (a doctoral candidate in psychology), the aim of their research effort based in Australia was to develop an epilepsy-specific HRQOL questionnaire for children to assess a variety of age-relevant domains, including physical function, emotional well-being, cognitive function, social function, and behavior. This review covers the development and validation work done on this Quality of Life in Childhood Epilepsy Questionnaire (QOLCE). It is a collaboration between the Sydney Children s Hospital and the Children s Hospital Westmead. In these settings, the research group demonstrated the reliability, validity, and sensitivity of their new scale in children with refractory epilepsy. Each child had their epilepsy syndrome defined by video-eeg monitoring using the criteria of the International League Against Epilepsy (ILAE). The group also has evaluated the psychometric properties of the new instrument in children with intellectual deficits and, as reported in preliminary fashion in a poster at the 2002 AES, in American children at Miami Children s Hospital. The QOLCE scale steps in development are outlined in Figure 2. As shown, the process resulted in development of 2 separate questionnaires, the first being an 87-item Child Seizure Profile, currently not published, Physical function Physical restrictions <.001 Energy/fatigue Cognitive function Attention/concentration Memory Language Other cognitive Emotional well-being Depression Anxiety Control/helplessness Self-esteem Social function Social interactions <.001 Social activities Stigma Behavior General health rating <.001 Quality-of-life rating 0.52 <.001 Overall quality-of-life score <.001 QOLCE = Quality of Life in Childhood Epilepsy. Figure 3. Sensitivity of QOLCE to Seizure Reduction QOLCE = Quality of Life in Childhood Epilepsy; QOL = quality of life. S688 Vol. 3 (7B) July 2003

6 and the second a 91-item QOLCE, which is the focus of this review. The full QOLCE questionnaire listing the specific questions related to physical function (12), emotional well-being (19), cognitive function (23), social function (12), and behavior (23) is available in the publication describing validation of this instrument. 21 Examples of negative and positive items are listed in Table 2. Two generic subscales (overall QOL and general health) were also included as part of the QOLCE. Parents took approximately 20 to 30 minutes to complete both questionnaires. They were told to focus on the past 4 weeks and they rated the life attribute statements with a 5-point Likert-type scale (eg, very often, fairly often, sometimes, almost never, never). Over 12 items were eventually rejected due to poor internal correlation, resulting in a 73-item scale. In general, the QOLCE instrument properties were assessed using the criteria recently suggested by the ILAE, including scoring (sufficient choice options), reliability, content validity, construct validity, criterion-related validity, and responsiveness to change. 7 In the first validation study, 63 parents or guardians of children with refractory epilepsy completed all evaluation forms. The study sample consisted of 32 girls and 31 boys; the mean age was 11 years and the mean age of seizure onset was 4.1 years. The results of the initial validation study established the psychometric properties of the scale. 21 The study showed that each scale correlated better with similar scales on established generic health measures (eg, CHQ, CBCL) than with dissimilar scales (ie, construct validity). Sensitivity of the QOLCE to epilepsy severity was also demonstrated. In particular, as seizure severity over the past 6 months increased in these patients, most of the HRQOL subscale scores decreased independently of age, gender, age of seizure onset, or IQ (Table 3). In a separate study presented in abstract form at the 2002 AES, a surgical population from Miami Children s hospital was evaluated. Those children with a 90% or greater reduction in seizures following surgery had a significantly better quality of life (Figure 3). A special study of the QOLCE in 30 children with refractory epilepsy and mild-to-moderate intellectual disability was also undertaken. 22 Results were compared with those from 64 matched children with epilepsy but with normal IQ. Measurement of HRQOL in populations with coexisting intellectual deficits has previously been problematic, but the Australian group was able to draw several conclusions from their results with the new QOLCE instrument. First, they showed that the HRQOL in all children with epilepsy is greatly affected, regardless of the intellectual ability level of the child. However, they also showed that the presence of intellectual deficit depressed the HRQOL outcomes, independent of the presence of epilepsy. Compared with 2 other generic measures of HRQOL, the QOLCE also proved more sensitive to the epilepsy variables of clinical interest (eg, age of onset, seizure frequency, and medications taken). In a separate analysis, the group also demonstrated that the overall QOLCE score was significantly higher in children with idiopathic epilepsy syndromes versus those with symptomatic forms of the disease (P<.01). Finally, as reported at the 2003 meeting of the AES, the QOLCE has now been validated in a population of 71 American children with epilepsy (26 girls, 45 boys), 66% of whom were Anglo American, 20% Hispanic, 10% African American, and 4% Asian American. 23 The mean age was 11 years and the mean age of seizure onset was 5.1 years. The internal consistency in this population was very good (Cronbach s alpha ranged from 0.76 to 0.97) and the QOLCE correlated well with similar subscales of the CHQ. Further, 13 of the 16 QOLCE subscales correlated significantly with parental ratings of seizure activity. The researchers concluded that the QOLCE has sound psychometric properties, is sensitive to disease severity, and can be used in Australia or the United States with minimal cross-cultural effects. This potentially valuable instrument, although still in development, has already provided clinicians with valuable insights into the need for counseling and education in children with both epilepsy and intellectual disabilities. The QOLCE appears to be more sensitive to variation in clinical variables than other less disease-specific pediatric HRQOL instruments. Further validation and refinement of this tool as an outcomes measure after medical or surgical intervention is anticipated. CONCLUSION This brief overview of the development of 2 epilepsy-specific HRQOL instruments should make clinicians aware of the heightened interest and great strides made in epilepsy QOL research. While the method- Advanced Studies in Medicine S689

7 ological details of questionnaire creation may seem arcane to nonresearchers, and while the technical matters involving reliability, validity, sensitivity, and interpretation are complex even to the researchers themselves, the intent and direction of this line of research is clear: to create tools that show us whether our patients with epilepsy are getting better or worse. Only careful work similar to that described here will improve the quality of our instruments for measuring quality of life a vital measure of epilepsy treatment success or failure. REFERENCES 1. Fisher RS, Vickrey BG, Gibson P, et al. The impact of epilepsy from the patient s perspective I. Descriptions and subjective perceptions. Epilepsy Res. 2000;41: Cramer JA. Quality of life assessment in clinical practice. Neurology. 1999;53(suppl 2):S49-S Berto P. Quality of life in patients with epilepsy and impact of treatments. Pharmacoeconomics. 2002;20: Leidy NK, Elixhauser A, Vickrey B, Means E, Willian MK. Seizure frequency and the health-related quality of life of adults with epilepsy. Neurology. 1999;53: Birbeck GL, Hays RD, Cui X, Vickrey BG. Seizure reduction and quality of life improvements in people with epilepsy. Epilepsia. 2002;43: Baker GA, Hesdon B, Marson AG. Quality-of-life and behavioral outcome measures in randomized controlled trials of antiepileptic drugs: a systematic review of methodology and reporting standards. Epilepsia. 2000;41: Cramer JA, Camfield C, Carpay H, et al. Principles of health-related quality of life: assessment in clinical trials. Epilepsia. 2002;43: Perucca E, Beghi E, Dulac O, Shorvon S, Tomson T. Assessing risk to benefit ratio in antiepileptic drug therapy. Epilepsy Res. 2000;41: Wiebe S, Eliasziw M, Matijevic S. Changes in quality of life in epilepsy: how large must they be to be real? Epilepsia. 2001;42: Sherman EM, Slick DJ, Connolly MB, et al. Validity of three measures of health-related quality of life in children with intractable epilepsy. Epilepsia. 2002;43: Gill TM, Feinstein AR. A critical appraisal of the quality of quality-of-life measurements. JAMA. 1994;272: Gilliam F, Kuzniecky R, Faught E, Black L, Carpenter G, Schrodt R. Patient-validated content of epilepsy-specific quality-of-life measurement. Epilepsia. 1997;38: Chaplin JE, Yepez R, Shorvon S, Floyd M. A quantitative approach to measuring the social effects of epilepsy. Neuroepidemiology. 1990;9: Gilliam F, Kuzniecky R, Meador K, et al. Patient-oriented outcome assessment after temporal lobectomy for refractory epilepsy. Neurology. 1999;53: Wiebe S, Matijevic S, Eliasziw M, Derry PA. Clinically important change in quality of life in epilepsy. J Neurol Neurosurg Psychiatry. 2002;73: Gilliam F, Wyllie E, Kashden J, et al. Epilepsy surgery outcome: comprehensive assessment in children. Neurology. 1997;48: Austin JK, Huster GA, Dunn DW, Risinger MW. Adolescents with active or inactive epilepsy or asthma: a comparison of quality of life. Epilepsia. 1996;37: Batzel LW, Dodrill CB, Dubinsky BL, et al. An objective method for the assessment of psychosocial problems in adolescents with epilepsy. Epilepsia. 1991;32: Cramer JA, Westbrook LE, Devinsky O, Perrine K, Glassman MB, Camfield C. Development of the Quality of Life in Epilepsy Inventory for Adolescents: the QOLIE-AD-48. Epilepsia. 1999;40: Ronen GM, Rosenbaum P, Law M, Streiner DL. Health-related quality of life in childhood epilepsy: the results of children s participation in identifying the components. Dev Med Child Neurol. 1999;41: Sabaz M, Cairns DR, Lawson JA, Nheu N, Bleasel AF, Bye AM. Validation of a new quality of life measure for children with epilepsy. Epilepsia. 2000;41: Sabaz M, Cairns DR, Lawson JA, Bleasel AF, Bye AM. The health-related quality of life of children with refractory epilepsy: a comparison of those with and without intellectual disability. Epilepsia. 2001;42: Sabaz M, Lawson JA, Cairns CR, et al. American validation of the quality of life in childhood epilepsy questionnaire. Epilepsia. 2002;43(suppl 7): S690 Vol. 3 (7B) July 2003