Visual Analog Scale Questionnaire to Assess Quality of Life Specific to Each Symptom of the International Prostate Symptom Score

Visual Analog Scale Questionnaire to Assess Quality of Life Specific to Each Symptom of the International Prostate Symptom Score

Visual Analog Scale Questionnaire to Assess Quality of Life Specific to Each Symptom of the International Prostate Symptom Score So Ushijima, Osamu Uk...

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Visual Analog Scale Questionnaire to Assess Quality of Life Specific to Each Symptom of the International Prostate Symptom Score So Ushijima, Osamu Ukimura,* Koji Okihara, Yoichi Mizutani, Akihiro Kawauchi and Tsuneharu Miki From the Department of Urology, Kyoto Prefectural University of Medicine, Kyoto, Japan

Purpose: We assessed patient quality of life specific to each of the 7 items on the International Prostate Symptom Score, as evaluated with a novel visual analog scale questionnaire. Materials and Methods: A total of 246 male patients with a chief complaint of lower urinary tract symptom were asked to complete the International Prostate Symptom Score and visual analog scale questionnaires to assess bother or satisfaction regarding patient quality of life specific to each of the 7 items on the International Prostate Symptom Score. Results: An item with the maximum visual analog scale measure matched the chief complaint in 169 patients (69%). In contrast, the chief complaint failed to match to an item with the most severe International Prostate Symptom Score in 104 patients (42%) (p ⫽ 0.012). Multiple regression analysis to define the best predictor of International Prostate Symptom Score quality of life score of the 14 items, including International Prostate Symptom Score and visual analog scale, revealed that the best predictor was the visual analog scale measure for nocturia (p ⫽ 0.0003), followed by visual analog scale measures for frequency (p ⫽ 0.0004) and incomplete emptying (p ⫽ 0.01). After ␣-blocker treatment improvement in the visual analog scale measure for the chief complaint correlated better with improvement in the International Prostate Symptom Score quality of life score than the change in International Prostate Symptom Score. The overall test-retest correlation for the visual analog scale questionnaire in 55 healthy elderly men and 44 patients with lower urinary tract symptoms was 0.772 and 0.742, respectively (p ⬍0.00001). Conclusions: The novel visual analog scale measure of quality of life specific to each of the 7 items on the International Prostate Symptom Score has a significant impact on identifying the patient chief complaint as well as on patient specific quality of life. Our study supports the concomitant use of the International Prostate Symptom Score and visual analog scale questionnaires. Key Words: prostate, questionnaires, urinary incontinence, quality of life, pain measurement

symptoms. Clinical data on QOL assessment are limited in terms of each of the 7 I-PSS questions. The VAS is a widely accepted questionnaire for measuring the impact of disease and effects of medical interventions with special reference to QOL.8 –12 A VAS typically consists of a horizontal line anchored with labels (not bothered or delighted and severely bothered or terrible) at opposite ends. The patient is instructed to regard the VAS as a continuum and make a mark at the point along the line corresponding to his current level of bother or satisfaction. The VAS has also been shown to be a useful measure in several urological studies.9 –12 However, to our knowledge the VAS questionnaire for assessing patient QOL specific to each of the 7 I-PSS items has not been evaluated to date. We report a novel VAS questionnaire to assess bother or satisfaction regarding these items. We assessed the impact of satisfaction specific to each I-PSS symptom on patient QOL using a novel VAS questionnaire with face scales.

ower urinary tract symptoms are common in older men and fundamentally they can cause bother, anxiety or morbidity. Around the world the severity and/or frequency of LUTS are most commonly quantified using the 7 I-PSS symptom questions.1–3 LUTS severity is well documented using I-PSS, which is essentially a clinical measure. Although the severe total score of I-PSS is likely to have great impact on QOL in patients with LUTS, individual patient bother or satisfaction may not directly correlate with the severity of each I-PSS symptom score.2,4 – 6 The most severe symptom of the 7 items in I-PSS may not necessarily match the most significant symptom that patients want to be treated. Physician assessment of QOL tends to underestimate patient bother from urinary symptoms.7 Every symptom associated with lower urinary tract dysfunction has a possible impact on QOL. For example, even 1 or 2 episodes of nocturia can have the most significant impact on QOL in a patient despite his complaint of higher scores for other

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MATERIALS AND METHODS Submitted for publication June 30, 2005. Study received University Hospital Ethics Committee approval. * Address for correspondence and requests for reprints: Department of Urology, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kyoto 602-8566, Japan (telephone: ⫹81-75-2515595; FAX: ⫹81-75-251-5598; e-mail: [email protected]).

0022-5347/06/1762-0665/0 THE JOURNAL OF UROLOGY® Copyright © 2006 by AMERICAN UROLOGICAL ASSOCIATION

This study was done at our institution. Patients were recruited as they presented to the urology outpatient clinic and were followed in the course of management at the same institution. Ethics approval was obtained from the Univer-

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Vol. 176, 665-671, August 2006 Printed in U.S.A. DOI:10.1016/j.juro.2006.03.031

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sity Hospital Ethics Committee before the study, and patient consent and consent for participants in the control group were then obtained. Between April 2003 and August 2004, 246 consecutive male patients with a median age of 67 years (range 46 to 84)

who had a chief complaint of LUTS visited the outpatient clinic. They were asked what the chief complaint was and were requested to complete an I-PSS questionnaire and a VAS questionnaire to assess their satisfaction specific to each I-PSS symptom on the QOL at baseline (fig. 1). The 46

FIG. 1. VAS questionnaire to assess bother or satisfaction regarding patient QOL specific to each of 7 I-PSS items. Question above VAS line was “How would you rate your bother? Please check (x) on the linear scale above in accordance with your satisfaction with each urinary symptom.” Among explanations of questionnaire 5 face scales were demonstrated to help understanding, including 1) laughing face to represent delighted or pleased above left end of VAS, 2) smiling face to represent mostly satisfied above left side to center of VAS, 3) face with neutral expression to represent neither satisfied and dissatisfied above center of VAS, 4) face in trouble to represent mostly dissatisfied above right side to center of VAS and 5) crying face to represent unhappy or terrible above right end of VAS. Only text above 10 cm line of VAS was delighted above left end and terrible above right end. In VAS questionnaire 7 items of I-PSS symptoms were indicated according to original I-PSS questionnaire. In addition, questionnaire for QOL due to total urinary symptoms was also reported using VAS scale with 10 cm line with same question above VAS as that with I-PSS QOL score.

VISUAL ANALOG SCALE QUESTIONNAIRE AND INTERNATIONAL PROSTATE SYMPTOM SCORE men on oral medication with an ␣-blocker (75 mg naftopidil daily) were asked to complete the I-PSS and VAS questionnaires again after treatment for 4 or 6 weeks. As comparison groups for VAS reliability and validity assessment, 55 healthy elderly men with a median age of 66 years (range 51 to 75) and 44 with a median age of 66 years (range 55 to 87) with LUTS were recruited for test-retest analysis at a 1-month interval. The 55 healthy elderly men included those older than 50 years who reported mild LUTS (I-PSS less than 8) but who were not bothered by and did not want any medical intervention for LUTS. They were selected at random from healthy elderly men who presented to our urology clinic as accompanying family of urological patients. For test-retest analysis all men were asked to complete the I-PSS and VAS questionnaires twice at an interval of 1 month to examine test-retest reliability with no treatment, as is simulated in clinical tests in patients comparing pretreatment and posttreatment conditions. The VAS used in this study was a 10 cm line ranging from delighted at the left end of the line to terrible at the right end of the line to determine patient bother or satisfaction specific to each of the 7 questions on the conventional I-PSS (fig. 1). The VAS included original face scales showing a series of faces graded in increasing intensity from delighted (smiling face) to terrible (crying face) to match patient perceptions with appropriate pictures of facial expressions along the VAS. The patient was instructed to regard the VAS as a continuum and mark an X at the point along the line corresponding to his current level (rate) of bother or satisfaction. We evaluated the validity of the rates (0 to 10 cm) of each VAS questionnaire in relationship to the scores (0 to 5) of each I-PSS, respectively; analyzed the correlation of the score of I-PSS and rate of VAS in each of the 7 questions; compared correlation between I-PSS QOL score and each rate on VAS vs correlation between I-PSS QOL score and each score on I-PSS; and analyzed correlations between the patient chief complaint and the maximum score of the 7 items on I-PSS as well as between the patient chief complaint and the maximum rate of the 7 items on VAS. Logistic regression analysis was used to identify the correlation between patient QOL and VAS measure outcomes. Multiple regression analysis was used to identify the best predictor of patient QOL on all 14 items, including the 7 scores on the I-PSS questionnaire and 7 rates on the VAS measures. We also evaluated the correlation between the change in the 7 VAS questionnaire items and the improvement in I-PSS QOL score after treatment with ␣-blocker for 4 or 6 weeks.

TABLE 1. VAS measures at initial interview in 246 patients and 55 healthy elderly men Mean Rate ⫾ SD (cm) VAS Measure

Pts

Controls

p Value

Incomplete emptying Frequency Intermittency Urgency Weak stream Hesitancy Nocturia Total QOL

4.1 ⫾ 2.6 4.7 ⫾ 2.7 4.0 ⫾ 2.8 4.3 ⫾ 2.7 5.2 ⫾ 2.6 3.7 ⫾ 2.6 4.9 ⫾ 2.8 5.5 ⫾ 2.5

1.8 ⫾ 2.1 1.7 ⫾ 1.7 1.4 ⫾ 1.8 1.4 ⫾ 1.7 2.9 ⫾ 2.3 1.3 ⫾ 1.6 1.7 ⫾ 1.9 2.1 ⫾ 1.8

0.000002 ⬍0.000001 ⬍0.000001 ⬍0.000001 0.000004 ⬍0.000001 ⬍0.000001 ⬍0.000001

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TABLE 2. Test-retest analysis in 55 healthy elderly men and 44 men with LUTS at 1 month using Spearman’s rank correlation coefficient IPSS

Healthy men: Incomplete emptying Frequency Intermittency Urgency Weak stream Hesitancy Nocturia Total QOL Overall LUTS: Incomplete emptying Frequency Intermittency Urgency Weak stream Hesitancy Nocturia Total QOL Overall

VAS

Coefficient

p Value

Coefficient

p Value

0.742 0.892 0.674 1.000 0.783 0.855 0.912 0.905 0.847

0.00005 0.000001 0.0002 ⬍0.000001 0.00002 0.000003 ⬍0.000001 ⬍0.000001 ⬍0.000001

0.870 0.732 0.742 0.721 0.613 0.813 0.768 0.789 0.772

0.000002 0.00006 0.00005 0.00008 0.0008 0.000009 0.00003 0.00002 ⬍0.000001

0.548 0.614 0.728 0.511 0.606 0.644 0.713 0.671 0.661

0.0003 0.00006 0.000002 0.0008 0.00007 0.00002 0.000003 0.00001 ⬍0.000001

0.681 0.869 0.677 0.650 0.737 0.627 0.732 0.824 0.742

0.000008 ⬍0.000001 0.000009 0.00002 0.000001 0.00004 0.000002 ⬍0.000001 ⬍0.000001

For statistical analysis group comparison between patients and controls was made using Mann-Whitney U test. Analysis of correlation, including test-retest analysis, was based on Spearman’s rank correlation coefficient. The chisquare test for a 2 ⫻ 2 table and Student t test for paired data were used to make comparisons. Data analysis was performed using the SPSS® for Windows™, version 8.0 and Statistica™ for Windows® statistical programs. A 5% level of statistical significance was used throughout the study. RESULTS In the 345 men, including 246 patients, 55 healthy elderly men and an additional 44 patients for test-retest analysis, a total of 444 interviews were completed and analyzed in this study. Table 1 compares rates of VAS measures at the initial interview between the 246 patients and the 55 healthy elderly men. All rates of the 7 VAS questionnaires showed a significant difference between patients and controls (p ⬍0.00001). On test-retest analysis of the 55 healthy elderly men after a 1-month interval the overall Spearman’s rank correlation coefficient for VAS measures was 0.772 (p ⬍0.000001), while that for I-PSS was 0.847 (p ⬍0.000001, table 2). On testretest analysis of the additional 44 patients with LUTS after a 1-month interval the overall Spearman’s rank correlation coefficient for VAS measures was 0.742, while that for I-PSS was 0.661 (each p ⬍0.000001, table 2). There was a significant correlation in all items between the VAS test-retest rates (table 2). These test-retest data in healthy elderly men and patients with LUTS indicated that the VAS was a reproducible method for measuring the impact of each symptom of the 7 I-PSS questions on the bother or satisfaction of older men concerning LUTS. We evaluated the correlation between the chief complaint and maximum score in 7 I-PSS scores as well as the maximum rate on 7 VAS questionnaires. The chief complaint matched the item with the maximum score of the 7 items on the I-PSS in 142 of the 246 patients (58%), while it failed to match in 104 (42%). In contrast, an item with the maximum

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FIG. 2. Overall VAS vs score distributions in 7 I-PSS or I-PSS QOL score items, including incomplete emptying, frequency, intermittence, urgency, weak stream, hesitancy, nocturia and QOL score.

rate assessed by the VAS questionnaire matched the chief complaint in 169 of the 246 patients (69%), while it failed to match in 77 (31%). This indicated that identification of the most severe I-PSS score was likely to miss the patient chief complaint. On the other hand, identification of the maximum rate on the 7 VAS questionnaires correlated significantly better with the patient chief complaint (2 ⫻ 2 chisquare test p ⫽ 0.012). Figure 2 shows the distribution of VAS rates vs I-PSS scores on the 7 items as well as the I-PSS QOL score. Table 3 shows a significant correlation in each of the 7 items as well as in total QOL between the I-PSS QOL score and VAS rates. We used simple logistic regression analysis to assess the correlation between the I-PSS QOL score and each score on the I-PSS as well as on each VAS measure rate (table 4). There was a significantly better correlation between the I-PSS QOL score and each VAS rate than between the I-PSS QOL score and each conventional I-PSS score. The correlation coefficient with the I-PSS QOL score was higher for VAS than for I-PSS in all 7 questions (table 4). For the 7 VAS items multiple stepwise linear regression analysis revealed that the best predictor of the I-PSS QOL

TABLE 3. Correlation in 7 items and total QOL between I-PSS QOL score and VAS rates

score was VAS nocturia (F 40.08, p ⬍0.000001), followed by VAS incomplete emptying (F 19.81, p ⫽ 0.00001), VAS frequency (F 16.68, p ⫽ 0.00006) and VAS weak stream (F 8.76, p ⫽ 0.003, table 5). However, in the current study VAS urgency (F 1.46, p ⫽ 0.2), VAS hesitancy (F 1.29, p ⫽ 0.3) and VAS intermittence (F 0.02, p ⫽ 0.8) were not significant predictors of I-PSS QOL (table 5). More importantly for defining the best predictor of I-PSS QOL score multiple stepwise linear regression analysis revealed that, of the 7 VAS measure items and the 7 I-PSS items, the best predictor was VAS nocturia (F 13.30, p ⫽ 0.0003), followed by VAS frequency (F 12.83, p ⫽ 0.0004) and VAS incomplete emptying (F 6.32, p ⫽ 0.0124, table 6). However, I-PSS incomplete emptying and I-PSS nocturia, which were ranked as 1 and 2 of the 7 conventional I-PSS items, ranked as only 4 and 5 of the 14 items (table 6). After ␣-blocker treatment improvement in the chief complaint VAS measure correlated better with improvement in the I-PSS QOL score than the change in I-PSS with the symptom of the chief complaint (r ⫽ 0.684 and 0.568, respectively, fig. 3).

TABLE 4. Simple logistic regression analysis of correlation of I-PSS QOL and each I-PSS item, and I-PSS QOL and each VAS item Coefficient

Coefficient Incomplete emptying Frequency Intermittency Urgency Weak stream Hesitancy Nocturia Total QOL Each p ⬍0.000001.

0.687 0.661 0.717 0.617 0.661 0.637 0.652 0.837

Incomplete emptying Frequency Intermittency Urgency Weak stream Hesitancy Nocturia Each p ⬍0.000001.

IPSS

VAS

0.531 0.503 0.409 0.475 0.446 0.350 0.407

0.552 0.659 0.463 0.552 0.535 0.409 0.604

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TABLE 5. Multiple stepwise linear regression analysis of best predictor of patient I-PSS QOL among 7 VAS items

Incomplete emptying Frequency Intermittency Urgency Weak stream Hesitancy Nocturia*

F

Coefficient

p Value

19.81 16.68 0.02 1.46 8.76 1.29 40.08

0.2374 0.2368 0.8835 0.2278 0.1680 0.2568 0.2842

0.00001 0.00006 0.8 0.2 0.003 0.3 ⬍0.000001

* Best predictor.

DISCUSSION Patient subjective perceptions of LUTS and its impact on QOL are clinically important for determining the indication and efficacy of the increased number of treatments.1,2 The I-PSS is a widely accepted, quantitative, objective assessment of the severity of the 7 symptoms and of total severity regarding LUTS.1–7 However, we often find that the severity of symptoms assessed by I-PSS does not correlate well with the subjective patient perception of bother or satisfaction, ie the impact on patient QOL. The impact on QOL can be measured objectively and several measurement instruments have been used, including the comprehensive I-PSS QOL score. The VAS is widely accepted for evaluating QOL quantitatively.8 –12 We developed a VAS questionnaire to assess the bother (or satisfaction) specific to each of the 7 I-PSS items on patient QOL using a VAS measure with a face rating scale (fig. 1). Because the severity of the symptom score alone does not necessarily reflect the degree to which patients are bothered by LUTS, patient satisfaction may not directly correlate with improvement in the most severe IPSS score. Importantly every I-PSS symptom could have an impact on QOL. This study shows that assessing the satisfaction or bother specific to each I-PSS questionnaire item has a significant impact on QOL in patients with LUTS. The symptom specific satisfaction had a significant correlation with the impact of treatment on QOL as well as with improvement of the complaint in patients who desired treatment for the symptom. This study also indicates the usefulness of VAS for assessing satisfaction specific to each item of the I-PSS questionnaire. Importantly assessment of the most severe I-PSS score alone is likely to miss the chief patient complaint. The use of this novel VAS questionnaire combined with the I-PSS questionnaire has great potential to improve urologist understanding of the most significant

TABLE 6. Multiple stepwise linear regression analysis of best predictor of I-PSS QOL of 14 items, including 7 VAS and 7 I-PSS items

VAS: Nocturia* Frequency Incomplete emptying I-PSS: Incomplete emptying Nocturia Urgency Weak stream * Best predictor.

F

Coefficient

p Value

13.30 12.83 6.32

0.2029 0.2261 0.1546

0.00031 0.00039 0.012

4.90 4.88 4.11 4.04

0.1321 0.1148 0.1098 0.1091

0.028 0.028 0.043 0.045

FIG. 3. Patient chief complaint. A, correlation between improved I-PSS QOL score and VAS measure change (r ⫽ 0.684, p ⬍0.0001). B, correlation between improved I-PSS QOL score and I-PSS change (r ⫽ 0.568, p ⫽ 0.0005).

symptom, that is the one with the most impact on a patient QOL and that which can be ameliorated by treatment. An aim of this study was to determine the reliability and reproducibility of the VAS questionnaire for each I-PSS symptom for clinical use. We observed that the VAS was a valid and reproducible method to measure the impact of each symptom in the 7 I-PSS questions on satisfaction in older patients with LUTS as well as in healthy elderly men who were not bothered by LUTS. In this study the VAS was capable of discriminating between different levels of perceived severity in the patient and control groups. This sug-

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gests that the VAS questionnaire has good construct validity. Face scales have been the most popular approach for eliciting self-reports of pain in children, although various formats are available.13,14 Elderly men as well as children often have difficulty in the abstract task of describing subjective experiences using verbal terms alone. In the novel VAS questionnaire we added face scales reflecting bother or satisfaction to make it easier for men with LUTS to match their perception with the appropriate pictures of facial expressions representing those scales. We believe that these faces along the VAS scales could improve the reliability and reproducibility of this questionnaire. Barry15 and Welch et al16 reported that men with mild symptoms were rarely bothered enough to desire treatment. However, we found the importance of identifying the symptom with the greatest impact on QOL in even mildly symptomatic patients using the VAS questionnaire. Even 1 or 2 episodes of nocturia can have a significant impact on QOL despite higher patient scores in other symptoms or even when a patient has only mild symptoms on the total I-PSS. Increasing recent reports focusing on nonsurgical treatment for BPH, such as Serenoa repens (saw palmetto) and, furthermore, ␣-blocker and 5␣-reductase inhibitors, could decrease the need for subsequent surgical intervention.17–20 Considering such advances in various treatment options in patients scoring from mild to severe on the total I-PSS, a genuine treatment option providing maximum patient benefit may become selectable according to patient specific satisfaction or bother, minimizing the complications of overtreatment. The primary goal of treating men with clinical benign prostatic hyperplasia could be to decrease the symptom severity of the chief complaint and relieve the risk of disease progression. Although total I-PSS decreased severity is a widely accepted key for judging the success of various treatments, we found the importance of identifying and treating the symptom with the most impact on patient QOL. Improvement in the symptoms associated with the chief complaint or with the most significant impact on patient QOL would affect the patient perception of successful treatment and overall satisfaction. Our study supports concomitant use of conventional I-PSS and VAS questionnaires, simultaneously determining the severity of symptoms by the I-PSS and the most significant symptom to impact on patient QOL by the VAS questionnaire.

Abbreviations and Acronyms I-PSS LUTS QOL VAS

International Prostate Symptom Score lower urinary tract symptoms quality of life visual analog scale

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CONCLUSIONS Using the VAS questionnaire the assessment of bother or satisfaction specific to each item on the I-PSS questionnaire had a significant impact on identifying the chief patient complaint as well as defining the symptom most correlated with patient QOL. Because effective treatment to improve the symptom most impacting QOL would likely lead to the greatest patient satisfaction, our study supports the concomitant use of conventional I-PSS and novel VAS questionnaires. This study warrants a further study in a larger number of patients to evaluate the usefulness of this novel VAS questionnaire for assessing QOL specific to each symptom on the I-PSS on the efficacy of the various treatments in patients with LUTS.

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