A Review of Condition-Specific Instruments to Assess the Impact of Urinary Incontinence on Health-Related Quality of Life

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1 European Urology European Urology 43 (2003) 219±225 A Review of Condition-Specific Instruments to Assess the Impact of Urinary Incontinence on Health-Related Quality of Life Tara Symonds * Outcomes Research, P zer Global Research & Development, Sandwich Laboratories, Sandwich, Kent CT13 9NJ, UK Accepted 17January 2003 Abstract To date, severity of symptoms of urinary tract conditions, such as overactive bladder (OAB) and stress incontinence, have been the main indicators used to understand the burden on the patient. However, there is also an impact on patients' health-related quality of life (HRQoL) that should also be assessed. A literature search was conducted and all HRQoL instruments published in peer-reviewed journals were evaluated. Ten instruments were identi ed: general use ( ve); urinary urge (OAB) incontinence (four); and stress incontinence (one). Several were identi ed as valid instruments for assessing HRQoL in urinary incontinence patients. # 2003 Elsevier Science B.V. All rights reserved. Keywords: Health-related quality of life; Incontinence; Assessment method 1. Introduction Urinary incontinence is the `involuntary loss of urine, which is objectively demonstrable, and a social or hygienic problem' [1]. Urinary incontinence can be de ned as follows: Urinary urge incontinence (UUI): the involuntary loss of urine associated with a strong desire to void [1]. More recently, overactive bladder (OAB; urgency and frequency with or without urge incontinence), a relatively under-reported condition, has been used to describe a group of urinary incontinence symptoms related to UUI [2,3]. Stress incontinence (SI): precipitated when pressure is exerted on the abdomen, e.g. by coughing. Mixed incontinence: a mixture of urge and stress incontinence. Functional incontinence: physical dif culty in getting to a toilet, such as mobility problems, sedation, etc. Assessment of the severity of the symptoms listed above has been the main indicator used to understand * Tel ; Fax: address: tara_symonds@sandwich.p zer.com (T. Symonds). the burden of the patient's condition. However, there is also an impact on the person's health-related quality of life (HRQoL). Loss of urinary control can affect the social, psychological, domestic, occupational, physical and sexual aspects of patients' lives [4]. The social and psychological consequences can be profound, leading to limitations in social activity, anxiety, embarrassment and isolation [5]. Incontinent patients are most likely to restrict their uid intake, restrict physical activity and avoid places without easy access to toilets [6]. Most studies carried out in the past decade indicate that urge symptomatology (including OAB symptoms) impacts more on HRQoL than stress incontinence [1,7,8]. The prevalence of incontinence depends on the population surveyed (type of urinary incontinence, sex and age). Prevalence in older adults (60 years) in the US was about 30%, with older women more likely to be affected [9], particularly by UUI [10]. In a British survey, incontinence was estimated to be over twice as prevalent in women (14%) than men (6.6%) [11]. Cost is also an issue. In a survey of incontinent patients aged 65 years, the cost was estimated to be $26.3 billion ($3565 per individual) [12]. These costs are likely to increase with a shift towards a larger elderly population /03/$ ± see front matter # 2003 Elsevier Science B.V. All rights reserved. doi: /s (03)

2 220 T. Symonds / European Urology 43 (2003) 219±225 Treatments for incontinence vary from behavioral therapy to pharmacotherapy. Urge, or OAB symptomatology, is probably the most prevalent condition and pharmacological agents are being developed for these symptoms. Studies on new and existing treatments should evaluate HRQoL as well as ef cacy. However, the range of de nitions of HRQoL can hinder its measurement. The general consensus is that physical health, social health and emotional well-being should be assessed. Disease-speci c instruments are now more widely used and their suitability for assessing HRQoL in incontinent patients is presented. 2. Assessment of literature and analytical methods Instruments were identi ed through a systematic literature search on Medline (1966±2000) and the On-Line Guide to Quality of Life Assessment (OLGA) database [13]. Only instruments that appeared in peerreviewed journals were assessed. Instruments were assessed on rigor of development and validation. Features assessed were based on the basic standards for developing and validating a new HRQoL instrument [14]. The psychometric properties of each instrument (reliability, validity and sensitivity to change) were analyzed. Reliability tests that should ideally be conducted are: Internal consistency (goodness of t; scale 0±1 [1 ˆ perfect homogeneity of the items in the domain]. A correlation of >0.95 is excellent internal consistency. Reproducibility (test±retest reliability): indicates whether items are stable when no change is expected. A correlation of scores of >0.9 is excellent reproducibility. Basic validity tests that should be conducted are: Convergent/divergent validity: convergent validity tests whether the new instrument is actually measuring HRQoL (correlating scores with similar measures). A correlation of >0.4 would indicate adequate convergent validity. Divergent validity tests the new instrument against other instruments. Known-groups validity: the ability of the instrument to distinguish between theoretically distinct groups. Sensitivity to change: this determines whether a change in HRQoL would be detected if it had occurred. 3. HRQoL instruments Ten different instruments were identi ed and split into three categories: general urinary incontinence ( ve), UUI- or OAB-speci c (four) and SI-speci c (one) General urinary incontinence HRQoL instruments (Table 1) King's Health Questionnaire (KHQ) The KHQ was developed to assess HRQoL in women with general symptoms of incontinence [15], but it is also a valid and reliable instrument for use in both men and women with OAB symptoms [2,16]. It has 21 items representing eight domains: general Table 1 Psychometric properties of HRQoL instruments for general urinary incontinence conditions a Instrument Population sample Reliability Validity Sensitivity to Internal consistency Test±retest Convergent/ divergent Known-groups change KHQ UIÐwomen (n (10 weeks) OABÐmen (n ˆ 92) Sensitivity analysis: OABÐmen and women (n ˆ 338) ISQ-P UIÐwomen (n ˆ @ IIQ UIÐwomen (n (12 weeks) IIQ-7UIÐwomen (n ˆ 162) I-QOL UIÐmen and women (n @ (2 weeks) UIÐwomen (n ˆ 288) BFLUT c UIÐwomen (n ˆ 85) KHQ, King's Health Questionnaire; ISQ-P, Incontinence Stress Questionnaire for Patients; IIQ, Incontinence Impact Questionnaire; I-QOL, Incontinence Quality of Life; BFLUT, Bristol Female Lower Urinary Tract symptoms questionnaire. a Feature demonstrated (@); feature not demonstrated (); feature not clearly demonstrated (@/). b Institutionalized and cognitively impaired. c Only reliability and validity scores for the symptom domain were given (not the HRQoL or sexual functioning domain).

3 T. Symonds / European Urology 43 (2003) 219± health, incontinence impact, role limitations, physical and social limitations, personal limitations, emotional problems, sleep/energy disturbance, and severity measures. The reliability and validity of the instrument was assessed in 285 women with various incontinence symptoms, e.g. stress, detrusor instability, mixed, and sensory urgency. All domains showed reasonable internal consistency (alpha scores >0.7) and excellent reproducibility. To test for convergent validity, 193 women also completed the SF-36 [17] (only the common domains were correlated). All similar domains were statistically signi cantly correlated with each other (0.34±0.64), indicating reasonably good convergence. The KHQ was sensitive to change in 338 men and women with OAB receiving either oxybutynin or tolterodine in a 10-week naturalistic study [2]. Results from a larger study (n ˆ 1284) support this [16,18] Incontinence Stress Questionnaire for Patients (ISQ-P) The ISQ-P was developed to assess the psychological distress associated with urinary incontinence in long-term care [19]. The instrument has 20 items covering three domains: depression, aesthetic/somatic, and social functioning. A sample of 96 women (mean age 85.3 years) was used to assess the psychometrics of the instrument. The reliability of the instrument was high (0.90) and reproducibility (assessed after 11 weeks) showed moderate correlation. Convergent validity was acceptable, with the relevant domains statistically signi cantly correlating with similar domains on the Center for Epidemiological Studies-Depression Scale (CES-D) [20] and the Psychological General Well-Being (PGWB) instrument [21] Incontinence Impact Questionnaire (IIQ) Details of two new instruments for assessing the impact of urinary incontinence symptoms in women have been described [22]: the IIQ and Urogenital Distress Inventory (UDI). The UDI is not reviewed because it is more a measure of `bothersomeness' of symptoms than an assessment of HRQoL. The IIQ questionnaire has 30 items comprising four domains: physical activity, travel, social relationships and emotional health. Internal consistency was high for each domain (all >0.86) and convergent validity of IIQ was demonstrated. Test±retest reliability was not assessed. Sensitivity was shown with a signi cant change in all domains seen over a 3-month treatment period (behavioral intervention, estrogen replacement therapy or surgical treatment). Since the initial development of IIQ, a short-form version has been produced which uses seven items from each domain of the original version [23]. Validity and reliability analyses of the IIQ-7were not given and no additional papers documenting its psychometric properties were identi ed in the literature Incontinence Quality of Life Instrument (I-QOL) The 22 items of the I-QOL were produced by interviewing patients with urge, stress and mixed incontinence [24]. Psychometric testing of the instrument was carried out using 62 urinary incontinent patients. Reliability of the instrument was excellent. Correlations with both the PGWB and the functioning items on the SF-36 indicated satisfactory convergent validity. Known-groups validity was also shown, the I-QOL scores being signi cantly (p < 0:0001) worse as severity, self-perceived severity, and number of medical appointments to treat incontinence in the past year increased. Further developments to the I-QOL instrument have been described in a study involving 141 stress and 147 mixed incontinent women [25]. The internal consistency (0.95), reproducibility (0.91), convergent validity, and sensitivity to change of the instrument were con rmed Bristol Female Lower Urinary Tract symptoms questionnaire (BFLUT) The BFLUT assesses symptom bothersomeness (20 items), HRQoL (nine items), and sexual function (four items) [26]. Only validation details of the 20-symptom/ bother items were presented. To date, no information on the validation of the HRQoL/sexual function items is available Evaluation Four of ve instruments developed to assess impact of general incontinence symptoms on HRQoL have good reliability and validity data. The KHQ has reliable and valid properties for use in incontinent women, with further testing of the instrument demonstrating its use in both men and women with OAB. The eight domains of the KHQ ensure that HRQoL issues are covered. The I-QOL is a well-validated instrument, particularly in women who have stress incontinence or mixed incontinence. Total score may not be relevant if speci c aspects of HRQoL are targeted for assessment, for example, if a particular therapy is more likely to impact positively on some aspects of HRQoL than others. The IIQ also appears to be a reliable and valid instrument for assessing the impact of general incontinence symptoms in women. The short-form version,

4 222 T. Symonds / European Urology 43 (2003) 219±225 IIQ-7, will need complete validation and reliability testing before recommendations can be made. Furthermore, although the ISQ-P showed some acceptable psychometric results it is, perhaps, the most restricted instrument in terms of use, i.e. cognitively impaired, institutionalized women. The BFLUT requires appropriate testing of the whole instrument, including the HRQoL and sexual functioning items, before further recommendations are made. Arguably, instruments speci cally designed to assess HRQoL issues will be able to cover more than the nine items of the BFLUT. Urinary incontinence may not be as prevalent in men as in women but the impact of symptoms on HRQoL is the same [27]. Therefore, instruments should also be developed and validated for use in men. The I-QOL, IIQ and ISQ-P need further testing before use in incontinent men, while the KHQ requires further testing in men with incontinence symptoms other than OAB. I-QOL, IIQ and KHQ have demonstrated sensitivity to change, but only the KHQ has shown this in men. The I-QOL needs to be tested over a treatment period >2 weeks. No data are available about changes related to placebo-like effects and, thus, the clinical meaningfulness of the changes in HRQoL is dif cult to ascertain Urge incontinent-speci c (or OAB) HRQoL (Table 2) King's Health Questionnaire (KHQ) Refer to general incontinence section Incontinence Quality of Life Index (IQoLI) The IQoLI instrument addresses the social, emotional and physical impact of UUI symptoms using 29 questions [28]. Reliability and validity were tested in a double-blind, randomized clinical trial involving 79 women. Four items were insensitive to change and were dropped from further analyses. The remaining 25-item instrument showed good reliability (reproducibility 0.92, internal consistency 0.9). Convergent validity with the PGWB [21] instrument was adequate (0.4). The sensitivity of the instrument to change was demonstrated over 3 months of treatment with emepronium carrageenate or placebo. Additional evidence of sensitivity to change was demonstrated in a 12-week trial in 214 OAB patients receiving oxybutynin, tolterodine or placebo [2] Quality of Life Questionnaire for Urgent Micturition The Urgent Micturition instrument has 24 items grouped into ve dimensions: activities (eight items), emotional repercussions ( ve), self-image ( ve), sleep (three), and well-being (three) [29]. The internal reliability and reproducibility of the dimensions were suf cient with scores of >0.70 and >0.80, respectively. The known-groups validity was also goodðscores were signi cantly lower as symptoms increased in severity. Convergent validity and sensitivity to change were not reported Urge Impact Scale The Urge Impact Scale (URIS-24) measures three areas of HRQoL: psychological burden, personal control, and self-concept [30]. To assess its psychometric properties the URIS-24 was administered to 48 urge incontinent patients aged 57±89 years. The internal consistency of the whole instrument was excellent (0.94), as was test±retest reliability (0.88). The validity of the instrument was determined by correlating Table 2 Psychometric properties of HRQoL instruments for use in urinary urge speci c conditions a Instrument Population sample Reliability Validity Sensitivity to Internal consistency Test±retest Convergent/ divergent Known-groups change IQoLI UUIÐwomen (n @ (12 weeks) Sensitivity to changeðoab men and women (n ˆ 214) QoL Questionnaire for Urgent micturitionsðwomen (n @ Urgent Micturitions URIS-24 UUIÐmen and women (n Urge Incontinence Impact Questionnaire UUIÐwomen (n @ (12 weeks) UUIÐmen and women (n ˆ 257) IQoLI, Incontinence Quality of Life Index; QoL, Quality of Life; URIS-24, Urge Impact Scale. a Feature demonstrated (@); feature not demonstrated (); feature not clearly demonstrated (@/).

5 T. Symonds / European Urology 43 (2003) 219± incontinence frequency with URIS-24 scores; the result was ambiguous. Known-groups validity and sensitivity to change were not analyzed Urge Incontinence Impact Questionnaire (U-IIQ) Urge-speci c items have been added to the domains of the IIQ [31]. The additional items were developed by focus group interviews, clinical opinion and literature review, and the new instrument tested on women with urge or mixed incontinence (n ˆ 83). Forty women completed the instrument twice over a 2-week period. The U-IIQ has six domains: travel, activities, feelings, physical activities, relationships, and sexual function. Internal consistency for all domains was high (>0.90), except the physical activities domain (0.74). Test±retest reliability was good for activities, feelings and relationships (>0.85), while physical activities, travel and sexual function had acceptable values (>0.70). Convergent and divergent validity were addressed by correlating U- IIQ domains with the respective domains of the SF-36. However, the resulting correlation coef cients did not clearly con rm convergent validity. The known-groups validity and sensitivity to change of the instrument has also since been reported [32] Evaluation The most promising of the three urge incontinent speci c instruments is the U-IIQ. Two studies have provided psychometric evidence for its reliability, validity and sensitivity to change [31,32]; however, speci c validation in men is needed. The sexual function domain is the weakest domain, possibly because of the low number of sexually active participants (n ˆ 23) [31]. For wider use in evaluating new treatments in incontinence more evidence should be provided on the instrument's ability to detect a clinically meaningful changeðthe changes documented for the U-IIQ were not large. Its sensitivity also needs to be determined versus placebo. The KHQ has been speci cally tested in OAB patients and its consideration for use is warranted, not only because it has been validated in both men and women, but also because of its sensitivity to change in this group. The IQoLI has acceptable reliability and validity, but discrepancies in its sensitivity to change means that its clinical meaningfulness is dif cult to determine. Further work is needed to clarify this. The URIS-24 is a promising instrument for use in UUI patients regardless of sex, despite that fact that psychometric analyses have been limited to 48-yearold UUI patients to date. Additional testing is necessary before recommendations can be made. Furthermore, a greater understanding is required of the divergent, convergent and known-groups validity of the instrument and, if the instrument is considered for use in clinical trials, its sensitivity to change. The Quality of Life Questionnaire for Urgent Micturition showed good general psychometric properties but its applicability is limited because of the selection of female patients with symptoms of urgent micturition Stress incontinence speci c HRQoL instrument (Table 3) Symptom Impact Index for Stress Incontinence Two instruments were developed: one to assess symptom severity and the other to assess symptom impact. The symptom impact instrument measures the effect on HRQoL (11 items) and is reviewed here. Using a sample of 442 women, various psychometric analyses were conducted. Internal consistency of the SII-SI was reasonable at 0.77, and test±retest reliability was satisfactory [33]. Prior surgery and body mass index (BMI) were used to assess convergent validity. There was poor correlation with prior surgery but signi cant correlation with BMI. Known-groups validity was poor, with no discrimination between groups with different lengths of history with SI Evaluation Although the SII-SI items were thoroughly researched for comprehensibility and relevance some of the psychometric properties were questionable. For example, correlating scores with BMI determined the convergent validity of the instrument, but why this was chosen over Table 3 Psychometric properties of HRQoL instruments for stress incontinence conditions a Instrument Population sample Reliability Validity Sensitivity to change Internal consistency Test±retest Convergent/divergent Known-groups SII-SI SIÐwomen (n @ SII-SI, Symptom Impact Index for Stress Incontinence. a Feature demonstrated (@); feature not demonstrated ().

6 224 T. Symonds / European Urology 43 (2003) 219±225 more suitable assessments of convergent validity, such as similar constructs on other HRQoL instruments, is unknown. Known-groups validity was not shown which suggests poor sensitivity to change. Currently, one of the general incontinence instruments may be a better starting point to determine HRQoL in SI women. 4. Conclusions There are a number of reliable and valid instruments for assessing the impact of incontinence symptomatology on HRQoL. Currently, the general instruments are the more psychometrically robust, particularly the KHQ [15] and I-QoL [24]. Of the speci c UUI instruments, U- UIIQ [31] is a promising instrument for assessing HRQoL in OAB (or UUI) patients. The KHQ, a general incontinence questionnaire, is also an appropriate instrument for use in OAB patients. SII-SI, speci cally developed for use in SI patients, requires further psychometric assessment before recommendations can be made. Choice of instrument will invariably be decided by the population under consideration. If an instrument is chosen that has not been validated for that group, then validity testing should be a primary objective. Patrick et al. [25] highlighted this issue when they obtained lower convergent validity correlations between the I- QOL and other instruments than previously obtained by others [24], noting it was ``possibly due to differences in study populations that included men''. Instruments showing strong psychometric properties in one group may not display this property in another group. Before deciding on an instrument, the content of the instrument's items should be thoroughly reviewed to ensure that a particular aspect of HRQoL does not need additional assessment. For example, if the aim is to ascertain the impact of incontinence on sleep and energy issues then the KHQ might be a more useful tool to use over, say, the I-QOL, in which a total score is calculated. 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