Post-polio syndrome: impact of hope on quality of life

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1 Disability & Rehabilitation, 2012; 34(10): Copyright 2012 Informa UK, Ltd. ISSN print/issn online DOI: / RESEARCH paper Post-polio syndrome: impact of hope on quality of life Shimon Shiri 1, Isaiah D. Wexler 2, Uri Feintuch 3, Zeev Meiner 1 & Isabella Schwartz 1 1 Departments of Physical and Medical Rehabilitation, 2 Pediatrics, and 3 School of Occupational Therapy, Hadassah University Hospital, Mount Scopus, Jerusalem, Israel Disabil Rehabil Downloaded from informahealthcare.com by Hebrew University on 07/01/14 Purpose: To determine the effect of future-oriented coping strategies on the quality of life (QOL) of individuals with post-polio syndrome (PPS). Methods: A correlative study, in which a cohort of 61 patients was surveyed and a group of 40 healthy, age-matched individuals served as controls. Patients were surveyed as to their QOL, levels of hope and utilization of proactive coping, employment status and degree of functionality. Results: PPS patients had lower total, physical and mental QOL indices compared to controls. Future-oriented coping strategies associated with hope were positively associated with physical and mental QOL in the PPS group, but not in the controls. In a multivariate analysis, hope and employment status predicted higher QOL among those with PPS. Conclusions: Future-oriented coping strategies, particularly hope are distinctively associated with improved QOL benefits in PPS patients. Fostering future-oriented coping related to hope may improve the self-perceived mental and physical status of patients with PPS. Keywords: coping, hope, polio, quality of life, type A personality Introduction Despite successful efforts toward eradicating poliomyelitis, it still represents a significant medical burden. In 1995, the World Health Organization estimated that there were million people worldwide suffering from disabilities related to poliomyelitis [1]. Many of these individuals experience a recurrence of the original polio-related manifestations as well as symptoms of weakness, generalized fatigue, muscle atrophy and/or myalgia, which are characterized as post-polio syndrome (PPS) [1 4]. PPS develops in 25% 50% of patients with poliomyelitis and usually occurs years after the initial infection with the poliovirus [1,3]. Implications for rehabilitation Coping styles of individuals with post-polio can be conceptualized in terms of positive-optimistic psychological constructs rather than the traditional negative frame of reference. Hope is distinctively associated with improved quality of life among post-polio patients. Enhancing hope through psychotherapy may improve mental and physical health of individuals with postpolio. The psychological characteristics of individuals with PPS have been extensively studied [5 10]. Clark et al. [11] suggested that the development of new muscle weakness in PPS patients was not related to underlying psychopathology. However, individuals surviving the initial episode of paralytic polio had to develop specific coping strategies that allowed them to deal with the challenges associated with their physical disabilities. The onset of post-polio symptomatology forces these individuals to modify coping styles [12,13]. Studies of patients with PPS have shown that this syndrome has a negative impact on both functional capabilities and quality of life (QOL) [7,14 20]. Negative manifestations connected to PPS include depression, anxiety, hostility, low life satisfaction [8,14], fatigue [21] and hypochondriacal symptoms [22]. In spite of the associated psychological burdens, patients with PPS are better educated and have higher rates of employment compared to other disabled populations [23]. These achievements were often attributed to manifestations of a compulsive type A behavioral pattern that is oriented toward achieving a sense of control and normalcy [24,25]. Type A behavior represents a pattern of intense ambition associated with competitive, aggressive and persistent behavioral styles [26]. The rigid qualities associated with this behavioral pattern The authors Shimon Shiri and Isaiah D. Wexler contributed equally to this work. Correspondence: Shimon Shiri, PhD, Department of Physical and Medical Rehabilitation, Hadassah University Hospital, Mount Scopus, Jerusalem, Israel. Tel: Fax: shimonshiri@hadassah.org.i (Accepted September 2011) 824

2 have potential deleterious effects on the success of rehabilitation programs for PPS because of patient inflexibility regarding lifestyle changes and compliance with time-consuming rehabilitation protocols [27]. In contrast, recent reports suggest that the coping style of individuals with PPS is often adaptive and not consistent with a type A phenotype. Individuals with PPS often express satisfaction with their circumstances, and in one study, almost a quarter of the surveyed patients stated that living with polio helped them to achieve personal growth and increased strength [28]. Most individuals with PPS view their life as good and productive and have a sense of fulfillment regarding their ambitions in the realms of work and family [12]. In accordance with these latter reports, we hypothesize that the well-being of patients with PPS is related to optimistic future-oriented thinking, which provides patients with a positive point of reference to their present status. Future-oriented thinking encompasses attitudes and cognitive behavioral modes reflecting optimistic orientations toward the future such as hope and proactive coping [29,30]. In the context of future-oriented thinking, hope is defined in terms of agency and pathways [30]. Agency relates to the motivational components necessary for consistent and sustained efforts that are requisite for achieving goals. Pathways refer to the perceived methods for achieving established goals. Proactive coping comprises the ability to develop internal resources, which enhances coping with challenges and facilitates personal growth [29,31,32]. The purpose of this study was to examine the associations between optimistic future-oriented thinking and QOL among patients with PPS. The importance of this association relates to earlier studies showing that coping behavior is a major determinant of QOL in chronic diseases [33 37]. We also examined the association of QOL with other factors such as level of function and work. Methods The study was done at Hadassah University Hospital Post-Polio Clinic between 2007 and The study was approved by the Hadassah University Institutional Review Board (Helsinki Committee) and all subjects participating in the study signed an informed consent form. Based on sample size calculations, a recruitment goal of 60 patients with PPS was established based on a power analysis which showed that a sample size of 30 had sufficient statistical power (>80%) for revealing significant effects of moderate size. Similar sample sizes have been successfully used previously in other studies of this population [38,39]. Sixty-one patients with PPS were actually recruited and registered from the Hadassah Post-Polio clinic which follows approximately 100 patients per year. In a consecutive manner, patients visiting the clinic were interviewed, and those who fulfilled the diagnostic criteria of PPS based on Halstead s definition [40] were recruited for the study. The criteria for PPS were as follows: confirmed history of polio, partial or fairly complete neurological and functional recovery after the acute episode of polio, interval of at least 15 years with Post polio syndrome and impact of hope 825 neurological and functional stability, and the gradual or abrupt onset of new neurogenic (non-disuse) weakness in either previously affected or unaffected muscles. Associated manifestations include excessive fatigue, muscle pain, joint pain, decreased endurance and decreased function. Patients who agreed to participate in the study were administered the study instruments detailed below. Recruitment for the study was halted after reaching 61 patients. A control group of age-matched subjects consisting of 40 volunteers were recruited from the Jerusalem area. Recruitment of these individuals was done by the researchers of this study, and volunteers included professionals, university workers, blue-collar workers and unemployed. Study instruments Demographic and polio history questionnaire Demographic data were obtained including age, gender, family situation and employment status. With regard to polio, data included information regarding the initial poliomyelitis event (age, severity and need for mechanical ventilation), when and on what basis the diagnosis of PPS was made, and the current medical and functional status of the patient (surgical interventions, orthotics, assistive device requirements, mobility and frequency of falls). Hope scale The Hope Scale [30,41] is a valid, internally and temporally reliable trait self-report measure that includes 12 items (four on pathways, four on agency and four distracters) with participants rating their response on an eight-point Likert scale. The Hope Scale has been used in a wide variety of studies and samples, and has been found to predict outcomes related to academics, sports, psychotherapy and health [42,43]. The score for each respondent was based on the average of their responses for the 12 items. Based on Snyder s models of hope [43], patients were divided into high and low hopers based on the median with high hopers being defined as those scoring above the median hope score for the entire group. Proactive coping Proactive coping was assessed using the Proactive Coping subscale developed by Greenglass and colleagues [44]. The Proactive Coping subscale consists of 14 items and combines autonomous goal setting with self-regulatory goal attainment cognitions and behavior. Examples of items are, I always try to find a way to work around obstacles; nothing really stops me and I turn obstacles into positive experiences. Respondents were asked to indicate their degree of agreement with each item, using the following format: 1: not at all true, 2: barely true, 3: somewhat true and 4: completely true. Respondents proactive coping score was the average of their responses for the 14 items. The Cronbach s alpha coefficient was Previous studies indicate that the Proactive Coping subscale is a highly reliable and valid measure [44 46]. Physical and mental health was assessed using the Short- Form-36 (SF-36) instrument. The questionnaire included a Hebrew version of the Medical Outcomes Study SF 36 instrument Copyright 2012 Informa UK Ltd.

3 826 S. Shiri et al. [47,48]. This instrument includes 36 questions measuring eight health domains including physical functioning (PF), physical limitations in roles performance such as work (RP), pain (BP), general health (GH), emotional and mental well-being (MH), emotional limitations (such as pain, anxiety or depression) in roles performance (RE), social functioning (SF) and vitality (VT). Each domain is measured on a scale, where a score of 100 signifies perfect health. For purposes of evaluation, the SF-36 is divided into two categories relating to physical and mental subscales and the sum of the scores is the total QOL. Statistical analyses Data were entered into a Microsoft Excel file (Microsoft, Redmond, WA, USA) and then transferred to a statistical analysis program (SPSS 18.0; SPSS Inc., Chicago, IL, USA). Parametric statistics were used to compare the PPS to the control group. Pearson s correlation and partial correlations were determined for the different variables associated with PPS. Multivariate analysis for the different aspects of QOL as the outcome variable was done by forced entry utilizing variables with a correlation to QOL greater than 10. Using analysis of covariance (ANCOVA) and factorial analysis of variance (ANOVA), the relationship among hope, work and different components of QOL was performed as explained in the results section. Results The demographic characteristics of the PPS cohort and the age-matched healthy controls are shown in Table I. Also included in this table is the frequency of the different clinical manifestations of PPS. There were no significant difference between the two groups with regard to age, gender and marital status. There was a significant difference in level of education, with the control group having more years of education. As expected, level of functioning was lower in the PPS group as indicated by significant differences in employment, need for assistance and mobility. QOL as assessed by the SF-36 survey instrument and future-oriented coping scales (hope and proactive coping) are presented in Table II. For all the categories of QOL, there were significant, nearly two-fold, differences between the PPS and control groups. With regard to hope and proactive coping, there were smaller but still significant differences between the two groups. The interrelationship between clinical and functional status, different aspects of QOL, and future-oriented coping for patients with PPS was examined and the results are shown in Table III. As expected, there was a high correlation between physical and mental aspects of QOL. With regard to clinical and functional status, work was highly correlated with both physical and mental QOL. There was also a lower but significant correlation between work and hope. In terms of futureoriented coping, there was a strong link between hope and the total SF-36 (0.49). Coping also correlated with the total SF-36 and mental QOL, but to a lesser degree. Table I. Characteristics of study cohorts. PPS (n = 61) Controls (n = 40) p Age (years), mean (SD) 55.1 (6.0) 55.3 (8.3) Males, n (%) 31 (50.8) 16 (40.0) a Married, n (%) 46 (75.4) 32 (80.0) a Education (years), mean (SD) 12.4 (2.1) 14.8 (2.7) <0.001 Employed, n (%) 31 (50.8) 35 (87.5) <0.001 PPS clinical manifestations b Fatigue 52 (85.2) Recurrent muscle weakness 58 (95.1) New muscle weakness 52 (85.2) Myalgia 51 (83.6) Joint pain 51 (83.6) Breathing difficulties 10 (16.4) Assistance in daily life activities, n (%) 20 (38) 1 (2.5) <0.001 Driving, n (%) 49 (80.3) 38 (95) Wheelchair n (%) 10 (16.4) 0 <0.001 PPS, post-polio syndrome. a Three participants of the control group did not provide their gender and marital status. b Frequency of PPS manifestations only applicable to post-polio patients. Table II. Quality of life and future-oriented coping. PPS (n = 61) Controls (n = 40) p Physical health, mean (SD) 32.1 (17.2) 77.8 (17.2) <0.001 Mental health, mean (SD) 46.4 (22.1) 76.8 (18.1) <0.001 Total SF-36 score, mean (SD) 38.7 (19.3) 79.6 (17.7) <0.001 Hope score, mean (SD) 3.2 (0.5) 3.4 (0.4) Coping score, mean (SD) 2.9 (0.5) 3.1 (0.4) PPS, post-polio syndrome; SF-36, Short-Form-36. The level of correlation between hope and coping was 0.53, suggesting that the hope and coping questionnaires survey different attributes of future-oriented coping. To determine whether both were independently related to QOL as measured by the total SF-36 score, partial correlation analysis was done. When controlling for hope, the partial correlation coefficient for coping is 0.13, whereas the partial correlation coefficient for hope when coping is controlled is 0.44 (p = 0.003). This would most likely indicate that hope is independently associated with both QOL and proactive coping. To determine the impact of specific variables on the different aspects of QOL, regression analysis was done using the variables in Table III, whose correlation coefficient with the total SF-36 and the mental and physical subscales was As shown in Table IV, only work and hope were found to be significant for the total SF-36. Performing the same analysis with the physical and mental subscales as the outcome measure, work was a significant predictor of physical QOL while hope predicted mental QOL. To better understand the relationship between work and hope and their possible interaction, two types of ANOVA were performed. In the first, hope was treated as a covariate in ANCOVA. Both work and hope had a significant and nearly equal impact on the SF-36 as indicated by their respective effect size (η 2 ). For the physical subscale, only work was significant. In contrast, hope has a much greater effect on the mental QOL subscale than work (Table V). Disability & Rehabilitation

4 Post polio syndrome and impact of hope 827 Table III. Intercorrelations between quality of life and future-oriented coping in PPS patients. Work ADL Driving WC Hope Coping SF-36 Physical Mental Work 1.0 ADL Driving WC *** Hope 0.30* Coping *** 1.0 SF *** 0.33* *** 0.35* 1.0 Physical 0.49*** 0.36* * 0.41** *** 1.0 Mental 0.39** *** 0.41** 0.96*** 0.84*** 1.0 ADL, Activities of daily living; PPS, post-polio syndrome; SF-36, Short-Form-36 WC; Wheell Chair ridden. *p 0.05; **p 0.01; ***p Disabil Rehabil Downloaded from informahealthcare.com by Hebrew University on 07/01/14 Table IV. Predictors of changes in quality of life. a Predictor variables B (SE) β F (df) Adj. R 2 Total SF 6.8 (4,40)*** 0.35 Hope 14.0 (5.5) 0.33* Work 12.5 (5.1) 0.33* Physical 5.1 (5,39)** 0.32 Hope 8.5 (5.1) 0.23 Work 13.3 (4.7) 0.39** Mental 7.2 (4,40)*** 0.36 Hope 22.4 (6.1) 0.47** Work 9.3 (5.7) 0.22 SF, social functioning. *p 0.05; **p 0.01; ***p a The Variance Inflation Factor (VIF) was low ( ) throughout all the regressions. To better understand the interaction between work and hope, the results of the hope survey were dichotomized for those with high or low hope. The results of the factorial ANOVA using work status and level of hope showed that there was a significant interaction between the two. Graphing the interaction, it can be seen that hope has its greatest impact on QOL for those who are not working, and this holds true for both the total SF-36 and the two subscales. In terms of the total SF-36 and the physical subscale, employment compensates for those with low hope, and there is little difference between those from either the high or low hope group if individuals were employed. However, a different pattern is seen for the mental QOL subscale. Work status does not significantly impact on the mental QOL, and individuals who are employed but are in the low hope group do not attain the QOL as seen for those in the high group regardless of the employment status. Discussion The findings of this study indicate that among individuals with PPS, there is an association between optimistic futureoriented coping strategies and QOL. Our data indicate that QOL is significantly predicted by higher scores on the hope scale and work status. Hope was associated primarily with the mental health aspects of the SF-36, whereas employment was primarily associated the physical aspects of QOL. When subgroup analysis was performed, the relationship between hope and QOL was significant for those who were not employed. For individuals with PPS who were employed, hope was minimally associated with QOL, and this group was more Table V. Quality of life as related to hope and work. (a) ANCOVA using hope as the covariate Quality of life Factor F (1,43) Effect size (η 2 ) Adj. R 2 SF Work 8.8** Hope 7.7** Physical 0.30 Work 10.7** Hope Mental 0.36 Work 4.5* Hope 14.5*** (b) Factorial ANOVA: interaction between work and hope Quality of life Factor F (1,42) Effect size (η2) Adj. R 2 SF Work 12.6** Hope 7.4** Hope work 5.9* Physical 0.32 Work 14.3*** Hope Hope work 4.7* Mental 0.41 Work 7.6** Hope 15.9*** Hope work 5.8* ANCOVA, analysis of variance; ANOVA, analysis of variance; SF-36, Short-Form-36. *p 0.05; **p 0.01; ***p similar to the control group for whom there was no association between hope and QOL. There was a significant interaction between work and hope when QOL was analyzed in the context of those with high versus low levels of hope. Snyder and colleagues [30,42] delineated two components of hope: the will to obtain a meaningful and desirable goal and the ability to formulate strategies for obtaining the soughtafter goals (agency). The findings in our study regarding hope are compatible with previous reports indicating the robustness and distinctiveness of hope in relation to other major constructs of positive psychology, including self-efficacy and optimism. In a study of 204 university students, Magaletta and Oliver found that the will component of Snyder s construct of hope while associated with the concept of selfefficacy has a distinctive and independent prediction power of well-being that goes beyond that which would be predicted by Copyright 2012 Informa UK Ltd.

5 828 S. Shiri et al. Figure 1. Association of work and hope with quality of life (QOL). QOL was assessed by the Short-Form-36 and divided into total (A), physical (B) and mental (C) components. Patients with post-polio syndrome were categorized as those with high hope (dashed line) or low hope (unbroken line). self-efficacy alone [49,50]. Similarly, the agency component of hope is significantly associated with the concept of optimism [51] and yet has its own independent, unique contribution for predicting well-being. The independent efficacy of hope with regard to coping with stressful medical situations is consistent with previous studies demonstrating that hope is an important factor in determining successful coping in a variety of medical settings [52,53]. In our analysis, we found that even though there was a high correlation between proactive coping and QOL, proactive coping did not predict QOL or its subcategories. Based on partial correlations and controlling for hope, it appears that hope predicts both proactive coping and QOL. This finding should be viewed in the context of the findings of Magaletta and Oliver who showed that constructs such as hope, efficacy and optimism are related and share common variance with regard to outcome variables such as well-being [50]. However, despite the overlap, these are independent variables reflecting different aspects of future-oriented thinking, and their impact on QOL and well-being can vary depending on the setting. One of the interesting findings is the impact of employment status on QOL and its interaction with proactive coping. Previous studies of post-polio and other chronic diseases have shown a positive association between work and QOL [12,34,54]. In this study, we found that among individuals with PPS, the highest level of association is between employment and the physical components of QOL and a more minimal but significant association with the mental aspects of QOL. Hope was minimally related to the physical component of QOL for patients with PPS who were employed. The impact of hope on the mental aspects of QOL was highly significant, and employment status had a minimal contribution to the mental component of QOL. A possible interpretation of these findings is that optimistic future-oriented coping in the form of hope is much more meaningful for people who are unemployed in terms of their physical well-being, whereas hope has a positive impact on the mental aspects of QOL regardless of the employment status. Alternatively, people who are employed are more likely to be in better physical condition and have a higher physical QOL. If this is the case, then the effect of hope on mental QOL is less likely to be related to either physical well-being or employment status. As noted earlier, previous studies identified the behavior of individuals with PPS and their academic and vocational achievements as manifestations of type A behavioral pattern. This type of behavior has been associated with negative health and social consequences, especially with regard to ischemic heart disease [55 59]. However, several studies suggest that when type A pattern is factor analyzed, two major dimensions appear: achievement striving and impatience/irritability [60,61]. While achievement striving reflects the extent to which people work hard and implement active lifestyles, the impatience/irritability dimension reflects temperament and time obsession which may have negative health consequences. Following these findings, Lee et al. [62] found that the achievement striving dimension of the type A behavior was associated with better academic achievement, similarly to optimism. With regard to PPS, it is possible that the labeling of type A was partially a consequence of their high educational, vocational and other accomplishments, which may reflect the achievement striving component of type A. Disability & Rehabilitation

6 The findings of the present study suggest an alternative frame of reference to the PPS struggle than the traditional negative one related to type A behavioral patterns. We show that factors other than those related to physical disability itself influence QOL, such as hope and employment. This is consistent with earlier studies such as that performed by Viemerö and Krause [34] who showed that among individuals with physical disabilities, one s life situation or QOL is a function of the individual s occupational activities, social integration and his/her sense of the meaning of life. Adopting an optimistic future-oriented coping style is associated with enhanced QOL, and this may serve as an interventional goal for those treating patients with PPS. Declaration of interest: The authors report no conflict of interest. There were no external funding sources for the study. References 1. Gonzalez H, Olsson T, Borg K. Management of postpolio syndrome. Lancet Neurol 2010;9: Howard RS. 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