Quality of life and related variables in patients with ankylosing spondylitis

Qual Life Res (2011) 20:543–549 DOI 10.1007/s11136-010-9771-9 Quality of life and related variables in patients with ankylosing spondylitis Hatice Bodur • Şebnem Ataman • Aylin Rezvani • Derya Soy Buğdaycı • Remzi Çevik • Murat Birtane • Ayşen Akıncı • Zuhal Altay • Rezzan Günaydın • Mahmut Yener • Hikmet Koçyiğit • Tuncay Duruöz • Pelin Yazgan • Engin Çakar • Gülümser Aydın • Simin Hepgüler • Lale Altan • Mehmet Kırnap • Neşe Ölmez • Raikan Soydemir • Erkan Kozanoğlu • Ajda Bal • Konçuy Sivrioğlu Murat Karkucak • Zafer Günendi • Accepted: 4 October 2010 / Published online: 27 October 2010 Ó Springer Science+Business Media B.V. 2010 Abstract Objectives To evaluate quality of life (QoL) and related variables in patients with ankylosing spondylitis (AS), a chronic inflammatory disease of the spine. Methods Nine-hundred and sixty-two patients with AS from the Turkish League Against Rheumatism AS Registry, who fulfilled the modified New York criteria, were enrolled. The patients were evaluated using the Assessment of SpondyloArthritis International Society core outcome Filiz M. Sertpoyraz, İzmir Tepecik Training & Research Hospital; Barış Nacır Ankara Training & Research Hospital; Ömer Faruk Şendur, Adnan Menderes University School of Medicine; Melek Sezgin Mersin University School of Medicine, Ferda Özkan, Ankara Physical Medicine and Rehabilitation Training & Research Hospital, Figen Ayhan Ankara Training & Research Hospital; Ali Sallı Selçuk University School of Medicine; O. Hakan Gündüz, Marmara University School of Medicine; Sami Hizmetli, Cumhuriyet University School of Medicine; Funda Atamaz, Ege University School of Medicine. H. Bodur (&) Ankara Numune Training & Research Hospital, Mürsel Uluç M, 937.S, 35/17, 06450 Ankara, Turkey e-mail: haticebodur@gmail.com Ş. Ataman Ankara University School of Medicine, Ankara, Turkey A. Rezvani Vakif Gureba Hospital, Istanbul, Turkey D. S. Buğdaycı İstanbul Physical Medicine & Rehabilitation Training & Research Hospital, Istanbul, Turkey R. Çevik Dicle University School of Medicine, Diyarbakir, Turkey domains including Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), fatigue (BASDAI-question 1), pain (last week/spine/due to AS), Bath Ankylosing Spondylitis Functional Index (BASFI), Bath Ankylosing Spondylitis Metrology Index (BASMI), Bath Ankylosing Spondylitis Radiology Index (BASRI), Maastricht Ankylosing Spondylitis Enthesitis Score (MASES) and two QoL questionnaires (the disease-specific ASQoL and generic the Short Form-36 [SF-36]). Results The mean ASQoL score was 7.1 ± 5.7. SF-36 subscales of general health, physical role and bodily pain had the poorest scores. ASQoL was strongly correlated with disease duration, BASDAI, fatigue, BASFI, BASMI, BASRI, MASES, pain and SF-36 subscales (P \ 0.001). SF-36 subscales were also strongly correlated with A. Akıncı Hacettepe University School of Medicine, Ankara, Turkey Z. Altay İnönü University School of Medicine, Malatya, Turkey R. Günaydın İzmir Training & Research Hospital, Izmir, Turkey M. Yener Süleyman Demirel University School of Medicine, Isparta, Turkey H. Koçyiğit İzmir Atatürk Training & Research Hospital, Izmir, Turkey T. Duruöz Celal Bayar University School of Medicine, Manisa, Turkey M. Birtane Trakya University School of Medicine, Edirne, Turkey 123 544 Qual Life Res (2011) 20:543–549 BASDAI and BASFI. Advanced educational status and regular exercise habits positively affected QoL, while smoking negatively affected QoL. Conclusions In patients with AS, the most significant variables associated with QoL were BASDAI, BASFI, fatigue and pain. ASQoL was noted to be a short, rapid and simple patient-reported outcome (PRO) instrument and strongly correlated with SF-36 subscales. (SF-36) Health Survey, which is a generic measure of health status, and the AS Quality of Life Questionnaire (ASQoL) [3, 4]. The aim of the present study was to evaluate QoL and related variables in Turkish patients with AS. Methods Study population Keywords Ankylosing spondylitis
Quality of life Ankylosing spondylitis (AS) is a chronic inflammatory disease of the spine with unknown etiology. Manifesting with pain, joint stiffness and loss of spinal mobility, the disease particularly affects the young adult and productiveage men. These clinical symptoms and subsequent disease progression result in substantial functional limitations and impairment of health-related quality of life (HRQoL) [1, 2]. There is a growing interest in quality of life (QoL) assessments and the use of patient-reported outcome (PRO) measures in chronic disabling diseases. These parameters have become increasingly useful to evaluate the effectiveness of new treatment strategies, especially the antitumor necrosis factor (TNF) agents. Given the impact of AS on HRQoL domains, especially pain, physical functioning, fatigue and psychological well-being, PRO measures are extremely useful tools. Currently, two PRO instruments are employed in the evaluation of HRQoL in AS. These include Medical Outcome Short Form 36 A total of 962 patients with AS (733 men and 229 women) who included in the Turkish League Against Rheumatism Registry were enrolled in the study. The sociodemographic characteristics (age, gender, disease duration, educational status, marital status, smoking habit, alcohol use) of the patients were recorded. The patients were assessed using Assessment of SpondyloArthritis International Society (ASAS) recommendations for core outcome domains for the assessment in AS (5). Turkish versions of Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) (6), fatigue (BASDAI-question 1, Visual analogue scale 0–100) [6], Turkish version of Bath Ankylosing Spondylitis Functional Index (BASFI) [7], Bath Ankylosing Spondylitis Metrology Index (BASMI) [5] and Maastricht Ankylosing Spondylitis Enthesitis Score (MASES) [8] were used, and pain (last week/spine/due to AS, last week/spine/night due to AS) VAS (visual analogue scale 0–100) [5] were evaluated. The Bath Ankylosing Spondylitis Radiology Index (BASRI) was used for evaluating the radiological damage. AP pelvis, lateral cervical and lateral lumbar spine radiographs were taken. Sacroiliac and hip joint and spine were scored on a simple scale between 0 and 4 (0 = normal, P. Yazgan Harran University School of Medicine, Sanliurfa, Turkey R. Soydemir Şişli Etfal Training & Research Hospital, Istanbul, Turkey E. Çakar GATA Haydarpaşa Training & Research Hospital, Istanbul, Turkey E. Kozanoğlu Çukurova University School of Medicine, Adana, Turkey Introduction G. Aydın Kırıkkale University School of Medicine, Kirikkale, Turkey A. Bal Dışkapı Yıldırım Beyazıt Training & Research Hospital, Ankara, Turkey S. Hepgüler Ege University School of Medicine, Izmir, Turkey K. Sivrioğlu Uludağ University School of Medicine, Bursa, Turkey L. Altan Uludağ University School of Medicine, Bursa, Turkey M. Karkucak Karadeniz Technical University School of Medicine, Trabzon, Turkey M. Kırnap Erciyes University School of Medicine, Kayseri, Turkey N. Ölmez İzmir Atatürk Training & Research Hospital, Izmir, Turkey 123 Z. Günendi Gazi University School of Medicine, Ankara, Turkey Qual Life Res (2011) 20:543–549 545 1 = suspicious, 2 = mild, 3 = moderate, 4 = severe) These scores added together to produce the BASRI score (2–16) [9]. Turkish versions of two QoL questionnaires, a disease-specific measure entitled AS Quality of Life (ASQoL) [10] and a generic measure entitled Short Form-36 (SF-36) [11] were performed. ASQoL comprises 18 items and each item is scored as ‘1’ or ‘0’. A score of ‘1’ indicates poor QoL. Total scores range from 0 to 18, with a higher score indicating poor quality of life [10]. SF-36 evaluates eight dimensions of physical health and mental health within the previous 4 weeks. These include physical functioning, physical role, bodily pain, general health, vitality, social functioning, emotional role and mental health. Each domain is scored ranging from 0 to 100, and higher scores indicate good QoL [11]. Before the study, in order to provide standardization among the centers, interactive meetings and practical applications were performed. Booklets on physical and radiographical assessment methods were provided to the centers that participated. Statistical analysis The statistical analysis of the study was performed using Statistical Package for the Social Sciences (SPSS Inc., Chicago, IL, USA) version 13 for windows. Correlations between study parameters were evaluated by Spearman correlation test. As variables did not show normal distribution, non-parametric test was used, and the comparison of data between two groups was made using Mann– Whitney U test whereas Wilcoxon test was used when more than two groups. Statistical significance was considered P \ 0.01 with 99% confidence interval. Results In the present study, 962 patients with AS (733 men and 229 women) were enrolled, with a male/female ratio of 3.2. The mean age of the patients was 39.4 ± 10.5 years (range of 18–75 years), and the mean disease duration was 11.0 ± 8.5 years (median, 9.0). Clinical characteristics of the study population are summarized in Table 1. In Fig. 1, box plot graphics of BASRI spine and BASRI total values are shown. Mean ASQoL score was found to be 7.1 ± 5.7 (median, 6.0). The poorest SF-36 subscale scores were in general health, physical role and bodily pain and vitality (Table 1). Peripheral arthritis was present in 13% of the patients. ASQoL was strongly correlated with disease duration, BASDAI, fatigue, BASFI, BASMI, BASRI, MASES, pain at night and total pain and SF-36 subscales (Table 2). Age was found to be negatively correlated only with SF-36 subscale of physical functioning (P \ 0.001). Disease duration was correlated with SF-36 physical functioning (P \ 0.001), pain and general health subscales (P \ 0.05). BASRI was correlated with physical functioning Table 1 Clinical characteristics of the patients Age (years) Mean ± SD Median Range 39.4 ± 10.5 39 18–75 Disease duration (years) 11 ± 8.5 9 1–50 BASDAI 3.5 ± 2.4 3 0–10 Fatigue (BASDAI-question 1) BASFI 41 ± 28.9 3.0 ± 2.6 40 2.4 0–100 0–10 BASMI 3.4 ± 2.4 3 0–10 BASRI 8.0 ± 3.9 8 2–16 MASES (n = 232) 3.9 ± 2.9 3 1–13 36.1 ± 30.4 30 0–100 Pain (last week/spine/due to AS) 38 ± 28.6 35 0–100 ASQoL 7.1 ± 5.7 6 0–18 Pain (last week/spine/night due to AS) SF-36 SD standard deviation Physical functioning 65.8 ± 25.3 70 0–100 Physical role 51.4 ± 43.1 50 0–100 Bodily pain 53.9 ± 25.5 51 0–100 General health 45.3 ± 22.0 45 0–100 Vitality 53.8 ± 21.0 55 0–100 Social functioning 68.6 ± 24.6 75 0–100 Emotional role Mental health 54.7 ± 43.2 56.3 ± 13.4 67 56 0–100 0–100 123 546 Qual Life Res (2011) 20:543–549 best scores belonged to patients with college/university or master degrees and the poorest scores belonged to illiterates. Marital status The 20 of our patients were widow, 206 of them were single and 736 of them were married. There was no significant difference between patients according to their marital status in terms of QoL scores, except for the SF-36 physical functioning subscale. The SF-36 physical functioning subscale scores of widowed patients were the poorest followed by married and single patients (mean values were 58.1 ± 32.9, 64.2 ± 25.657 and 68.8 ± 23.3 respectively), (P \ 0.05). Smoking and alcohol About half of the patients were current smokers (47.8%) and 9.3% consumed alcohol. The mean ASQoL score was 7.3 ± 5.7 (median, 6.0) in non-smokers and 6.3 ± 5.4 (median, 5.5) in smokers. The difference was statistically significant (P \ 0.05), and ASQoL was found to be poorer in smokers. However, there was no significant difference between smokers and non-smokers regarding SF-36 subscale scores. Moreover, no significant difference was noted in ASQoL and SF-36 scores between patients who did or did not consume alcohol. Exercise habits Fig. 1 The box plot graphics of BASRI values (P \ 0.001), general health and mental health (P \ 0.05) subscales (Table 2). Patients with high disease activity (BASDAI C 4) had significantly poor QoL scores than patients with low disease activity (BASDAI \ 4; P \ 0.001; Table 3). When the patients were compared according to their functional status, it was observed that patients with worse functional status (BASFI C 5) had significantly poor QoL scores compared to patients with better functional status (BASFI \ 5; P \ 0.001 Table 4). Education The education levels of our patients were as follows: primary school 33.5%, middle school 14.8%, high school 25.9%, college/university 18.6%, master degree 5.3%, illiterate 2.0%. When the patients were classified according to their educational status, QoL was observed to be good in patients with higher educational status (P \ 0.001). The 123 Only 22.7% of the patients had regular exercise habits. Quality of life scores of patients with regular exercise habits, except the SF-36 social functioning subscale scores, were better compared to patients with no regular exercise habits. The mean ASQoL score was 7.7 ± 5.7 (median, 7.0) in patients with regular exercise habits and 5.9 ± 5.3 (median, 4.0) in patients with regular exercise habit (P \ 0.001) PF, GH, vitality (P \ 0.001), PR, BP, ER, MH (P \ 0.05) scores were also better compared to patients with no regular exercise habits. Extraarticular manifestations Of the patients, 139 (14.5%) had uveitis (current/past history), 64 patients (6.7%) had mucocutaneous findings (including psoriasis) and 40 patients (4.2%) had inflammatory bowel disease (IBD). There were no significant differences in QoL between patients with and without current/past history of uveitis and mucocutaneous findings. However, SF-36 bodily pain, general health and emotional role subscale scores were worse in patients with IBD (P \ 0.05). Qual Life Res (2011) 20:543–549 547 Table 2 Correlation between QoL scores and study variables Age ASQoL 0.010 Disease duration BASDAI Fatigue BASFI BASDAI-q1 0.116* 0.686* 0.602* -0.127* -0.196* -0.644* -0.573* -0.023 0.655* BASMI 0.281* BASRI 0.138* MASES 0.337* Pain # (night) 0.547* Pain ## ASQoL 0.531* 1 SF-36 Physical functioning Physical role -0.257* -0.487* -0.483* -0.681* -0.525* -0.468* -0.536* -0.196* -0.062 -0.278* -0.429* -0.426* -0.599* 0.006 -0.083** -0.686* -0.572* -0.585* -0.183* -0.092 -0.295* -0.638* -0.636* -0.689* General health 0.017 -0.083** -0.581* -0.506* -0.522* -0.243* -0.142** -0.338* -0.471* -0.477* -0.643* Vitality 0.016 -0.026 -0.604* -0.584* -0.485* -0.175* -0.099 -0.348* -0.479* -0.478* -0.660* Social functioning -0.021 -0.050 -0.592* -0.515* -0.547* -0.161* -0.083 -0.246* -0.498* -0.476* -0.643* Emotional role -0.020 -0.051 -0.510* -0.469* -0.498* -0.182* -0.082 -0.254* -0.406* -0.400* -0.588* 0.006 -0.006 -0.406* -0.363* -0.316* -0.153* -0.149** -0.253* -0.272* -0.267* -0.421* Bodily pain Mental health -0.034 -0.720* -0.382* -0.250* SD standard deviation Spearman’s rho values are presented * P \ 0.001; ** P \ 0.05 # Pain (last week/spine/night due to AS) ## Pain (last week/spine/due to AS) Table 3 Comparison of QoL scores of patients according to their disease activity ASQoL BASDAI \ 4 (n = 577; 60%) BASDAI C4 (n = 385; 40%) Mean ± SD Mean ± SD Median Median P 4.56 ± 4.31 3.00 11.19 ± 5.13 12.00 0.000* Physical functioning 75.43 ± 20.63 80.00 49.61 ± 24.13 50.00 0.000* Physical role 65.41 ± 40.16 75.00 30.18 ± 38.40 0.00 0.000* Bodily pain 64.22 ± 22.59 62.00 34.99 ± 19.28 32.00 0.000* General health 53.49 ± 20.60 52.00 33.64 ± 18.80 30.00 0.000* Vitality Social functioning 61.89 ± 18.25 77.34 ± 20.43 60.00 75.00 40.16 ± 20.09 52.83 ± 23.30 40.00 50.00 0.000* 0.000* Emotional role 67.37 ± 40.04 100.00 33.97 ± 39.85 0.00 0.000* Mental health 59.95 ± 12.11 60.00 50.73 ± 14.19 52.00 0.000* SF-36 * P \ 0.001 Discussion The present study aimed to evaluate QoL and related variables in 962 patients with AS. SF-36 is the most commonly used tool to evaluate health-related QoL as a subjective perception of physiological and physical limitations due to underlying disease. ASQoL is a diseasespecific assessment tool, which is used as a valuable measure to evaluate the effects of disease activity and biological agents on QoL of patients with AS [12, 13].In the present study involving 962 patients with AS, QoL was assessed by both a disease-specific scale (ASQoL) and a generic scale (SF-36). Quality of life was observed to be affected in all patients. The poorest scores in SF-36 were noted in general health, physical role and bodily pain and vitality subscales. Similarly, in the study of Sallafi et al. [12] conducted on 164 patients with AS, all dimensions of SF-36 were significantly affected, with poor scores reported in physical role, emotional role, bodily pain and general health. Ozgul et al. [14] also reported in their series of 101 patients that physical role, general health and bodily pain were the most significantly affected dimensions. Correlation analyses between ASQoL and SF-36 subscales, and demographic, clinical and radiological 123 548 Qual Life Res (2011) 20:543–549 Table 4 Comparison of QoL scores of patients according to their functional status BASFI B5 (n = 721; 75%) Mean ± SD ASQoL BASFI [ 5 (n = 241; 25%) P Median Mean ± SD Median 5.46 ± 4.80 4.00 12.58 ± 4.72 14.00 0.000* 73.68 ± 19.99 80.00 38.60 ± 22.25 40.00 0.000* SF-36 Physical functioning Physical role 60.73 ± 41.08 75.00 22.54 ± 35.74 0.00 0.000* Bodily pain 59.32 ± 23.26 51.00 31.91 ± 21.64 31.00 0.000* General health 50.39 ± 20.80 50.00 30.81 ± 19.60 30.00 0.000* Vitality Social functioning 58.25 ± 19.72 74.35 ± 21.16 60.00 75.00 37.84 ± 20.61 46.63 ± 23.28 35.00 50.00 0.000* 0.000* Emotional role 63.78 ± 40.90 67.00 24.00 ± 35.55 0.00 0.000* Mental health 58.28 ± 13.14 60.00 50.15 ± 13.68 50.00 0.000* * P \ 0.001 parameters in terms of evaluating disease activity, severity of pain and functional status revealed that ASQoL was strongly correlated with BASDAI, BASFI, fatigue, night pain, and total pain (rho values: 0.686, 0.655, 0.602, 0.547 and 0.531, respectively). Moreover, ASQoL was also found to be correlated with MASES, BASMI, BASRI and disease duration. Similar to ASQoL results, the strongest correlations with SF-36 subscales were noted in BASDAI, BASFI, fatigue and pain. Thus, disease activity, functional status, fatigue and bodily pain could be considered as the most significant variables affecting quality of life in patients with AS. Accordingly, Zhao et al. [13] also reported that ASQoL was significantly and strongly correlated with BASFI, pain and BASDAI. Maastricht Ankylosing Spondylitis Enthesitis Score was found to be one of the most significantly correlated variables with ASQoL and SF-36 following BASDAI, BASFI, fatigue and pain. Turan et al. [15] also found in their pilot study with 37 patients that enthesitis, which was evaluated according to Mander Enthesitis Index, was the most significant correlated variable with SF-36 subscales in multiple regression analyses. Although fatigue has been considered as a major symptom of many rheumatic diseases, it has been mostly ignored in AS until recently. Moreover, in a recent study, it was reported that half of the patients with AS had severe fatigue, which was evaluated according to Multidimensional Fatigue Symptom Inventory.[16] In the present study, fatigue was observed to be strongly correlated with QoL, which was assessed by BASDAI-question 1. However, as fatigue is a multifactorial and multidimensional symptom, assessment by a comprehensive questionnaire might have been more informative. It was also observed that patients with high disease activity (BASDAI C 4) and worse functional status (BASFI C 5) had significantly poorer QoL scores. These 123 findings emphasize the considerable effects of disease activity and functional status on quality of life. Concerning the effects of extra-articular findings on QoL, the presence of IBD was found to have a negative effect on bodily pain, general health and emotional role subscales of SF-36; however, there was no difference in other subscales. Previous observations have indicated that functional disability develops faster in smokers, while exercise and good social support slow down the disease progression [17]. Consistent with these findings, the present study revealed that smoking and not performing regular exercise had a negative impact on QoL. These observations show that it is critical to educate patients with AS and increase their awareness of these issues. The present study also showed that QoL was significantly improved by increasing educational level, which is consistent with previous findings by Ozgul et al. [14]. In conclusion, this study demonstrated that BASDAI, BASFI, fatigue and pain being the most significant variables associated with QoL in patients with AS. Early diagnosis and effective treatment provide the improvement of pain, fatique, disease activity and prevent functional limitations, therefore improving the quality of life. Turkish version of ASQoL was noted to be a short, rapid and simple PRO instrument and strongly correlated with SF-36 subscales. We belive that ASQoL would serve for assessing disease impact and treatment planning and follow-up. Acknowledgments The authors express their gratitude to all members of the TRASD AS Study group for their cooperation and to Wyeth/Pfizer Company for the registery sponsorship. References 1. Bodur, H., Ataman, S., Akbulut, L., et al. (2008). Characteristics and medical management of patients with rheumatoid arthritis Qual Life Res (2011) 20:543–549 2. 3. 4. 5. 6. 7. 8. 9. 10. and ankylosing spondylitis. Clinical Rheumatology, 27, 1119–1125. doi:10.1007/s10067-008-0877-1. Bostan, E. E., Borman, P., Bodur, H., et al. (2003). 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