Quality of life in women with fibromyalgia

Introduction
Fibromyalgia (FM), one of the most common chronic musculoskeletal pain disorders of unknown origin, is characterized by widespread pain with tender points [1]. Fibromyalgia affects about 2% of the general population, 90% of whom are women [2], and is among the three most common diagnoses in ambulatory adult rheumatology practice [3]. In Iran, about 1.3% of the general population suffers from fibromyalgia [4]. Smith presented the diagnostic criteria of fibromyalgia for the first time in 1979 [1]. The current criteria for diagnosis of fibromyalgia are the ones of the American College of Rheumatology [4], which include widespread pain associated with tender points in 11 of the 18 particular points [5].
Fibromyalgia is usually associated with fatigue, sleep disorder, anxiety and depression [6], and like any other disabling conditions can significantly affect work capacity, family life, social relations and quality of life [7, 8]. White et al. mentioned negative effects of fibromyalgia on quality of life of patients who are at an economically productive age and report that the problems are caused by symptoms such as fatigue, lethargy, pain and in general, patients’ disability [9]. Nowadays, assessment of quality of life is an important issue in chronic diseases [10]. Researchers in different domains of health have studied fibromyalgic patients’ quality of life in different countries. For example, Israeli fibromyalgic patients had a lower score in quality of life scale (SF-36) than healthy people and those with widespread pain [11]. In another study in the United States, fibromyalgic patients gained a lower score in quality of life scale (SF-36) in all aspects when compared with the general population [12]. The same results were found in the Netherlands [13] and Brazil [14]. Quality of life is becoming more and more significant in health care systems. Since there has been no research done about quality of life in fibromyalgia patients in Iran, this study aimed to compare quality of life in fibromyalgia patients with that of healthy people.
Material and methods
To assess quality of life in women with fibromyalgia and to compare it with that of the healthy control group, we did a retrospective cross-sectional study in 2006. Eighty women with fibromyalgia attending the rheumatology clinic in Tehran were entered into the study based on inclusion criteria. Inclusion criteria were fibromyalgia diagnosis by a rheumatologist according to ACR 1990, age over 25, not having severe psychiatric diseases and willingness to participate. In addition, 74 healthy women, who were matched with the case group in age, marital status, education and occupation, were enrolled in the control group. Verbal consent was obtained from all patients prior to the interview.
Instruments
Two questionnaires of personal information (age, marital status, education and occupation) and a quality of life scale (SF-36) were used. SF-36 was made to assess quality of life [15] and evaluate 8 important aspects: physical functioning, role functioning physical, bodily pain, general health, vitality, social functioning, role functioning emotional, and mental health. In this questionnaire, patients are also asked to evaluate their general health in the past year [16]. The score of people on each scale varies between 0 and 100, where a higher score shows a better quality of life in that scale [17]. Several studies have proved SF-36 reliable and valid as a means of evaluating people’s quality of life [18]. Validity and reliability of SF-36 have been approved in Iran, as well [19]. Based on the results of this study, the reliability of all aspects of this questionnaire is suitable (internal correlation index of all eight aspects was between 0.70 and 0.85 and their re-test index after one week was between 0.43 and 0.79). Data were analyzed using SPSS13 and t-test.
Results
Subject characteristics
Subject characteristics by group are shown in Table I. The FMS patients were typical of those seen in our clinical setting: Eighty women with fibromyalgia with mean age of 42.9 ±9.1 and 74 healthy women with mean age of 37.2 ±10.3 made up the study population. Reported pain duration for patients was 10 years. Both the control group and the case group (fibromyalgia) were matched for education, occupation, age and marital status (Table I).
Quality of life in fibromyalgia patients and healthy women
Table II lists total and individual domain scores of SF-36 measurement. The comparison of quality of life between the case group and the control group showed a significant difference between mean scores of women with fibromyalgia and those of healthy women in the following subscales: physical functioning, physical role limitation, bodily pain, general health, vitality and emotional role limitation (p < 0.05 to p < 0.01). However, subscales of social functioning and mental health showed no significant difference between the two groups (Table II).
Association between health status and demographic characteristics
Table III shows the association (measured by Pearson’s correlation coefficient, r), for the 80 women with FM between eight domains of health status (SF-36) and some demographic characteristics such as age, education and marriage.
Strong associations (p < 0.01) were noted for age with physical functioning, role functioning physical, bodily pain, and vitality subscales. Education was moderately correlated (p < 0.01) with role functioning physical and bodily pain. Marriage had a low negative relation (p < 0.05) to role functioning physical.
Discussion
To our knowledge this is the first clinical study assessing quality of life in Iranian women with FM. The main objective of this study was to evaluate quality of life of women with fibromyalgia and its comparison with that of healthy women.
Statistical analyses of SF-36 subgroup parameters revealed that most domains of quality of life, including physical functioning, role functioning physical, bodily pain, general health, vitality, and role functioning emotional, were significantly impaired in the FM groups compared with those in healthy controls. Nevertheless, the role functioning physical domain in the FM group had the lowest scores compared with those in healthy controls (Table II). Our findings are in line with those of other researchers on quality of life in patients with fibromyalgia [11, 12, 20]. Supporting our findings, Neumann et al. [11] reported in a recent study that most subscales of SF-36 represent health dimensions relevant to patients with non-articular pain syndromes, namely FMS, and are useful to assess their quality of life. Patients with fibromyalgia have marked impairment in their functional status. The severity of impairment as assessed by SF-36 distinguishes patients with FMS from healthy individuals.
Fibromyalgia is a complex syndrome with significant effects on patients’ quality of life, function and finances. It seems that the disability secondary to chronic pain in patients is caused by past experience, self-esteem, motivation, excitement disorder, fatigue, cultural background and financial status [21]. Based on these findings, it can be supposed that cultural and ethnic factors may explain the insignificant difference between the two groups regarding mental health and social functioning, although it should be tested in inter-cultural studies to determine the effects of cultural and ethnic factors on quality of life in patients.
Since fibromyalgia negatively affects quality of life, it is important that fibromyalgia be approached and managed in a multidisciplinary manner. Once the diagnosis of fibromyalgia is made, it is essential that health care specialists try to improve patients’ function and reduce their complaints. This can be achieved by medical and non-medical interventions.
References
1. Goldenberg DL. Fibromyalgia and related syndrome. In: Klippel JH, Dieppe PA. Rheumatology. 2nd ed. UK, Mosbey CO1997; 1-12.
2. Monga TN, Tan G, Ostermann HJ, Monga U, Grabois M. Sexuality and sexual adjustment of patients with chronic pain. Disabil Rehabil 1998; 20: 317-29.
3. Offenbaecher M, Glatzeder K, Acknheil M. Self-reported depression, familial history of depression and fibromyalgia (FM), and psychological distress in patients with FM. J Rheumatol 1998; 57 (Suppl 2): 94-6.
4. Forqanizade J, Abhari R, Shakibi MR, Pirozan M, Samadi F, Tavakoli-Bazaz S. Prevalence of rheumatoid in Tehran. Journal of Iran University of Medical Sciences 1995; 3: 182-91.
5. Yunus MB. Fibromyalgia syndrome: Blueprint for reliable diagnosis. Consultation 1994; 12: 60-74.
6. Wallace DJ. The fibromyalgia syndrome. Ann Med 1997; 29: 9.
7. Gür A, Karakoc M, Nas K, Cevik R, Sarac J, Ataoglu S. Effects of low power laser and low dose amitriptiline therapy on clinical symptoms and quality of life in fibromyalgia: a single blind, placebo controlled study. Rheumatol Int 2002; 22: 188.
8. Berman JR, Bassuk J. Physiology and pathophysiology of female sexual function and dysfunction. World J Urol 2002; 20: 111-8.
9. White KP, Speechley M, Harth M, Ostbye T. Comparing self-reported function and work disability in 100 community cases of fibromyalgia syndrome versus controls in London, Ontario: the London Fibromyalgia Epidemiology Study. Arthritis Rheum 1999; 42: 76-83.
10. WHO Quality of Life Group: Study protocol for the World Health Organization project to develop a quality if life assessment instrument (WHOQOL). Qual Life Res 1993; 2: 153-9.
11. Neumann L, Berzak A, Buskila D. Measuring health status in Israeli patients with fibromyalgia syndrome and widespread pain and healthy individuals: utility of the short form 36-item health survey (SF-36). Semin Arthritis Rheum 2000; 129: 400-8.
12. Bennett RM, Schein J, Kosinski MR, Hewitt DJ, Jordan DM, Rosenthal NR. Impact of fibromyalgia pain on health-related quality of life before and after treatment with tramadol/acetaminophen. Arthritis Rheum 2005; 53: 519-27.
13. Picavet H, Hoeymans N. Health related quality of life in multiple musculoskeletal diseases: SF-36 and EQ-5D in the DMC3 study. Ann Rheum Dis 2004; 63: 723-9.
14. Martinez JE, Barauna Filho IS, Kubokawa K, Pedreira IS., Machado LA, Cevasco G. Evaluation of the quality of life in Brazilian women with fibromyalgia, through the medical outcome survey 36 item short-form study. Disabil Rehabil 2001; 23: 64-8.
15. Ware JE Jr, Sherbourne CD. The MOS 36 item short-form health survey (SF-36): Conceptual framework and item selection. Med Care 1992; 30: 473-83.
16. Jenkinson C, Coultrer A, Wright L. Short form 36 (SF 36) health survey questionnaire: normative data for adult of working age. Br Med J 1993; 306: 1437-40.
17. McHorney CA, Ware JE Jr, Raczek AE. The MOS 36- item short form health survey (SF-36): II. Psychometric clinical tests of validity in measuring physical and mental health constructs. Med Care 1993; 31: 247-63.
18. Garratt AM, Ruta DA., Abdalla MI, Buckingham JK, Russell IT. The SF-36 health survey questionnaire: an outcome measure suitable for routine use within the NHS. Br Med J 1993; 306: 1440-4.
19. Asghari-Moqadam MA, Faqihi S. Reliability and validity of SF-36 in two samples of Iran. Journal of Daneshvar 2003; 1: 1-10.
20. Ones K, Turkyilmaz A, Erden N. Assessment of quality of life in patients with fibromyalgia syndrome and chronic low back pain. Eur J Pain 2006; 110 (Suppl S1): S234.
21. Bennett RM. Multidisciplinary group programs to treat fibromyalgia patients. Rheum Dis Clin North Am 1996; 22: 351-67.