International Journal of Rheumatic Diseases 2012
ORIGINAL ARTICLE
Clinical characteristics of 150 consecutive fibromyalgia patients attending an Australian public hospital clinic Emma K. GUYMER,1,2 Paul MARUFF3 and Geoffrey O. LITTLEJOHN1,2 1 3
Department of Rheumatology, Monash Medical Centre, Clayton, 2Department of Medicine, Monash University, Clayton, and Centre for Neuroscience, University of Melbourne, Parkville, Victoria, Australia
Abstract Aim: To describe clinical characteristics of fibromyalgia in an Australian population. Method: Data was collected from 150 consecutive patients with clinical features of fibromyalgia seen in an Australian public hospital clinic. Demographic information and clinical characteristics were recorded. Significant correlations between clinical characteristics were identified, then used in multiple regression analyses to identify factors influencing outcome in physical function, pain, fatigue and sleep disturbance. Clinical features in groups who were or were not using different treatment strategies were compared. Results: Most patients were female and Caucasian. The majority reported a recognizable trigger factor and many had associated conditions, most commonly headache and irritable bowel syndrome. Physical function was significantly accounted for by pain levels (P = 0.001); pain score was significantly predicted by tenderness (P = 0.002) and physical function level (P = 0.001); fatigue levels were significantly influenced by age (P = 0.007) and sleep disturbance (P < 0.001), and sleep disturbance was significantly predicted by fatigue (P < 0.001). Just over one-third (34%) of patients were using fibromyalgia medications (low-dose tricyclic antidepressant, pregabalin or duloxetine); however, they had less anxiety (P = 0.006) and better reported physical function (P = 0.04) than those who were not. Less than half (43.6%) of the patients were regularly exercising; however, they had reduced overall illness impact scores (P = 0.004), better physical function (P = 0.01) and less fatigue (P = 0.03), anxiety (P = 0.02) and depressive features (P = 0.008) than non-exercisers. Conclusion: Baseline clinical characteristics in this group were comparable to other study populations. The use of management modalities with proven benefit in fibromyalgia was limited; however, those patients who were engaged in regular exercise or using medication had better self-reported outcome measures than those who were not. Key words: fibromyalgia characteristics, Australian population.
INTRODUCTION Fibromyalgia is a chronic illness characterized by a combination of chronic, widespread musculoskeletal pain and tenderness, together with varying degrees of
Correspondence: Dr Emma Guymer, Department of Rheumatology, 3rd Floor, Block E, Monash Medical Centre, 246 Clayton Road, Clayton, Vic. 3168, Australia. Email:
[email protected]
other symptoms, including fatigue, sleep disturbance, musculoskeletal stiffness, cognitive dysfunction and high levels of distress. There are often associated conditions, such as headache, irritable bowel syndrome and anxiety and depressive disorders. The prevalence of fibromyalgia is estimated to be between 2% and 5%, with women up to nine times more affected.1–3 Fibromyalgia is a debilitating illness, with symptoms leading to significant impairment and disability. A review of 37 studies of healthcare status
© 2012 The Authors International Journal of Rheumatic Diseases © 2012 Asia Pacific League of Associations for Rheumatology and Blackwell Publishing Asia Pty Ltd
E. K. Guymer et al.
showed the healthcare burden of fibromyalgia was greater than that of any other specific pain condition, including rheumatoid arthritis and osteoarthritis.4 Data from a US health insurance database of 33 176 patients with fibromyalgia found that patients with fibromyalgia showed higher rates of physical and psychological comorbidities, increased healthcare utilization costs, almost double the use of pain-related pharmacotherapy, and that total health care costs over 12 months were three times higher than a group of matched controls.5 Since the publication of the classification criteria by the American College of Rheumatology in 1990,6 there has been steady growth in understanding of the pathophysiology of fibromyalgia. Current evidence indicates fibromyalgia arises from abnormality in the central nervous system (CNS) processing of sensory information with altered function in pain pathways and neuroendocrine disturbance.7–9 It is likely that there are both genetic and environmental factors involved in the predisposition for fibromyalgia. For example, there is strong familial aggregation in offspring and first-degree relatives of people with fibromyalgia,10,11 and polymorphisms involving the catechol-O-methyltransferase (COMT) pathway, and some serotonin and dopamine receptor genes have been linked to specific symptoms of fibromyalgia, including pain threshold, pain severity and personality traits.12–15 The illness is often associated with an environmental triggering situation, such as illness, trauma or most commonly psychological stress.16 There is also an increasing understanding of effective therapies for fibromyalgia, with medications aimed at specific pathophysiological mechanisms producing effective results in rigorous clinical trials.17–24 Non-pharmacological therapies such as education, exercise and cognitive behavioral therapy also have proven benefits and remain essential parts of the multidisciplinary management paradigm.25–29 Despite agreement about the importance of understanding the clinical characteristics of fibromyalgia, there remains no published data regarding the characteristics of fibromyalgia in an Australian population. There is no current documented knowledge of Australian fibromyalgia prevalence, clinical profile, management and impact with which to inform policy and decision-making, and to compare to international published data. There is also no published information regarding the prevalence or healthcare costs of fibromyalgia in the Australian population. However, an analysis of the data from the Australian Bureau of Statistics National Health Survey 2007–2008 found that 39.3% of participants aged under 64 years of age without a
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specific diagnosis of fibromyalgia reported severe bodily pain that resulted in severe or profound core activity limitation in the 4 weeks prior to their interview.30 Although in this report we cannot address prevalence or some of the other above-mentioned aspects of fibromyalgia in Australia, we do, for the first time, present baseline information obtained from patients attending a specialist fibromyalgia outpatient clinic, run by rheumatology services in a large tertiary public hospital in Australia.
METHODS Data was collected from consecutive patients referred to the fibromyalgia outpatient clinic of a large tertiary public hospital in the south-eastern suburbs of Melbourne, Victoria, Australia between March 2008 and September 2010. The patients were seen at an initial visit by a rheumatologist where a history was taken and a physical examination was performed as standard care. Fibromyalgia diagnosis was based either on American College of Rheumatology (ACR) 1990 classification criteria6 or physician opinion, where the patient suffered widespread musculoskeletal pain and tenderness, together with other characteristic clinical features. Demographic data and clinical information were recorded. This clinical information included details of illness duration and characteristics, the presence of a recognizable trigger factor, details of current and past management, and any history of other medical problems. The use of one of three medications available at the time in Australia with evidence of significant benefit in the management of fibromyalgia (low-dose tricyclic antidepressant, duloxetine or pregabalin) was recorded. Patients’ height and weight were measured, and their body mass index (BMI) was calculated. A tender point examination was performed. Patients were asked to complete the Fibromyalgia Impact Questionnaire (FIQ).31 This 10-item, self-administered questionnaire measures physical function, work status, well-being, pain, stiffness, fatigue, sleep, anxiety and depression. It has been extensively used and validated since its development.32 The overall score has a maximum of 100, with higher scores indicating a higher illness impact. The average score for fibromyalgia patients is 50, with severely afflicted patients usually scoring above 70.32 There are individual sub-scores for physical function, work status and general well-being, as well as 10-cm visual analogue scales to record pain, stiffness, fatigue, sleep disturbance, anxiety and depressive symptoms. The maximum score for each of these is 10. ACR clinical
International Journal of Rheumatic Diseases 2012
Australian fibromyalgia characteristics
diagnostic criteria, in contrast to the classification criteria for fibromyalgia were published in 2010.33 Patients seen after this publication were also assessed using these new criteria, which include a Widespread Pain Index (WPI) that measures the number of painful body regions (out of 19) and a Symptom Severity score (SS) which assesses the severity of non-pain symptoms. The fibromyalgia case-definition using these new criteria is either WPI 7 and SS 5, or WPI 3–6 and SS 9. The above information was considered standard of care for the purposes of quality control in the setting of a routine public outpatient clinic, and as such, did not require formal institutional ethics approval. The subjects gave informed consent to the collection of data, anonymity was preserved and the project conformed to the provisions of the World Medical Association’s Declaration of Helsinki.
Data analysis Descriptive statistics for demographic information and patient characteristics were tabulated. To discern any difference between those patients who satisfied 1990 ACR classification criteria for fibromyalgia and those who did not, mean measures of illness characteristics, clinical state and treatment, were compared between these two groups using independent samples t-tests. Intercorrelations between ratings on the measures of physical function, pain, fatigue and sleep disturbance were examined using Spearman’s correlations. For the measure of physical function, statistically significant correlations with other illness and demographic characteristics were identified. These were then entered into a multiple regression analysis to determine the extent to which the different correlates independently predicted physical function. This same process was then repeated for the measures of pain, fatigue and sleep disturbance. To determine how different current treatment approaches influenced the illness outcomes in fibromyalgia at presentation, mean measures of self-reported clinical state were compared between patients receiving and not receiving pharmacotherapy, undertaking and not undertaking physical exercise, receiving or not receiving psychological therapy, and taking and not taking complementary medicines using a series of independent samples t-tests. Analyses were performed using the SPSS statistical package (version 17.0; SPSS Inc., Chicago, IL, USA). The criterion for statistical significance for each comparison was set 0.05. Although this criterion elevates the risk of Type I error in the statistical analysis, it was retained because measures on the different clinical variables were correlated and therefore use
International Journal of Rheumatic Diseases 2012
of a correction for Type I error that assumed independence (e.g. Bonferroni correction) is too conservative. Second, as this is one of the first large studies of clinical characteristics in fibromyalgia, it can be considered exploratory and hypotheses-generating. Therefore, correction for experiment-wise error may cause us to overlook important trends in the data.
RESULTS Patient characteristics One hundred and fifty consecutive patients were seen in the clinic during the study period. Of these 95 (63.3%) met ACR 1990 classification criteria, the remaining 55 were diagnosed with fibromyalgia by physician opinion despite having less than the requisite tender point score of 11 because they satisfied the other criteria and had clinical features characteristic of fibromyalgia. The demographic and clinical characteristics of the sample are shown in Tables 1 and 2. Patients were mostly female and Caucasian, with a mean age of almost 47 years. Most were referred from their general practitioner, 19.3% were referred by doctors working within the same hospital and 14.7% were referred from outside specialists and approximately half were receiving disability, compensation or other pension payments.
Illness characteristics The clinical characteristics of the sample are given in Tables 1 and 2. The majority of patients reported a recognizable trigger factor. Reported trigger factors were classified as psychosocial stress in 29.3%, physical illness in 10.7% and injury in 10%, with the remainder
Table 1 Demographic information and current therapy at presentation Percentage Female Caucasian GP referral Disability/pension payments Recognizable trigger On tricyclic antidepressant On duloxetine On pregabalin Current regular exercise Current pain psychology Pain psychology ever Current complementary therapy Complementary therapy ever
89.3% 83.3% 66% 41.3% 88.7% 28.2% 2.7% 4.7% 43.6% 12.8% 30.2% 46.3% 77.6%
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Table 2 Clinical characteristics of patients
Age (years) n = 150 Duration of symptoms (years) n = 150 Number of associated conditions n = 150 Number of tender points n = 149 BMI (kg/m2) n = 143 FIQ score (/100) n = 147 Physical function (/10) n = 147 Pain (/10) n = 147 Fatigue (/10) n = 147 Sleep disorder (/10) n = 147 Anxiety (/10) n = 147 Depressive features (/10) n = 147
Mean
SD
Minimum
Maximum
46.8 10.0
13.2 8.9
16 0.5
83 45
5.1
2.0
0
10
11.9
4.9
0
18
28.6 62.1
7.2 14.2
16.5 19.6
59.6 90.1
4.4
2.2
0
9.3
6.7 7.8 8.1
2.3 1.8 1.7
1 1.5 1
10 10 10
5.6 4.9
2.7 2.8
0 0
10 10
BMI, body mass index; FIQ, Fibromyalgia Impact Questionnaire; SD, standard deviation.
of the triggers occurring as a combination of these types. Many patients suffered comorbid conditions considered to be associated with fibromyalgia. The percentage of patients affected by different associated conditions is displayed in Figure 1, with the most common being recurrent headache and irritable bowel syndrome. Having a higher number of associated
conditions in this group of patients was correlated with a longer duration of symptoms (r = 0.13, P = 0.030), worse pain (r = 0.13, P = 0.029) and a higher illness impact (r = 0.26, P = 0.000). The group rated their illness impact as being particularly severe in the areas of pain, fatigue and sleep disturbance. Differences in clinical measures between those patients who did meet the ACR 1990 classification criteria are show in Table 3. Patients who met ACR 1990 classification criteria, when compared to the group who did not, had a significantly higher mean number of associated conditions (headache, irritable bowel syndrome, anxiety, restless legs syndrome, depression, temporomandibular joint disorder, multiple chemical sensitivities, irritable bladder syndrome, pelvic pain syndrome or vulvodynia) (P = 0.001), higher mean BMI (P = 0.005), and higher illness impact (P < 0.001) with worse self-reported physical functioning (P = 0.01), pain (P < 0.001), fatigue (P = 0.007), sleep disturbance (P = 0.005), anxiety (P = 0.04) and depressive symptoms (P = 0.001). These patients were also significantly less likely to currently be performing regular exercise (P = 0.001). There were a total of 23 patients included who additionally completed the 2010 WPI and SS score. Their mean scores for the WPI and the SS score were 12.8 (SD = 3.9) and 7.8 (SD = 2.6), respectively. The correlations between demographic and illness characteristics are shown in Table 4. Level of physical function was significantly accounted for only by pain levels (P < 0.001, total r2 = 0.164). Pain score was significantly influenced by tenderness (P = 0.002) and
80
Percent of group
70 60 50 40 30 20 10
le ss es t R
Vu lv od yn ia
le gs
w bo e bl ita Irr
4
sy nd ro Te m m e po ro D m ep an re di ss bu io la n M rj ul oi tip nt le di so ch rd em er ic al s Irr en ita si tiv bl e iti bl es ad de rs yn Pe dr om lv ic e pa in sy nd ro m e
ie ty nx A
el
H
sy nd
ro
ea da ch
m
e
e
0
Figure 1 Percentage of patients with associated conditions.
International Journal of Rheumatic Diseases 2012
Australian fibromyalgia characteristics
Table 3 Differences in clinical measures between patients who did and those who did not meet ACR 1990 classification criteria Patients who did not meet criteria (n = 55)*
Patients who met criteria (n = 95)*
4.4
5.5
0.001
1.1
BMI
26.5
29.9
0.005
3.4
Total FIQ score (/100) Physical function (/10)
54.6
66.3
< 0.001
11.7
3.8
4.7
0.01
0.9
Pain (/10)
5.6
7.3
< 0.001
1.7
Fatigue (/10)
7.3
8.1
0.007
0.8
Sleep (/10)
7.6
8.4
0.005
0.8
Anxiety (/10)
5.0
6.0
0.04
1.0
Depressive features (/10)
3.9
5.4
0.001
1.5
No. of associatedconditions
Pvalue
Mean difference
95% CI 1.75 1.75 5.79 1.04 16.06 7.26 1.73 0.24 2.47 1.00 1.41 0.22 1.37 0.25 1.85 0.42 2.46 0.65
*Values reported as mean (SD). P-value indicates significance of difference between patients meeting ACR 1990 criteria and those who did not. ACR, American College of Rheumatology; BMI, body mass index; FIQ, Fibromyalgia Impact Questionnaire.
Table 4 Correlations between patient demographic and illness characteristics Duration of symptoms Age Duration of symptoms No. associated conditions No. tender points BMI FIQ score Physical function Pain Fatigue Sleep Anxiety
0.109
No. associated conditions 0.090 0.129*
No. tender points
BMI
FIQ score
Physical function
Pain
Fatigue
Sleep
Anxiety
Dep.
0.005 0.022
0.082 0.049
0.034 0.106
0.105 0.031
0.081 0.032
0.148* 0.054
0.022 0.039
0.043 0.107
0.039 0.052
0.203**
0.042
0.265**
0.163**
0.133*
0.214**
0.200**
0.154*
0.135*
0.142*
0.312**
0.162**
0.283**
0.238**
0.175**
0.165**
0.203**
0.128*
0.107 0.374**
0.125* 0.485** 0.246**
0.086 0.418** 0.182**
0.123* 0.396** 0.066
0.053 0.397** 0.118*
0.107 0.435** 0.100
0.275**
0.237** 0.483**
0.195** 0.133* 0.156**
0.235** 0.194** 0.220** 0.423**
*P < 0.05; **P < 0.01; patient numbers as per Table 2. Non-parametric correlation coefficient calculations. Dep., depressive features; BMI, body mass index; FIQ, Fibromyalgia Impact Questionnaire.
physical function level (P = 0.001, total r2 = 0.269). Fatigue levels were significantly predicted by age (P = 0.007) and sleep disturbance (P < 0.000, total
International Journal of Rheumatic Diseases 2012
r2 = 0.376). Levels of sleep disturbance were predicted significantly only by fatigue (P < 0.000, total r2 = 0.339).
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Patient management With respect to management at the time of presentation to the clinic, 34.9% of patients were taking medication with evidence-based benefits in the management of fibromyalgia. More patients referred by general practitioners were currently taking fibromyalgia medication (37.4%), compared to only 13% of patients referred by external specialists. The most commonly used medication for fibromyalgia at time of presentation was a tricyclic antidepressant. Less than half the patients performed regular aerobic level exercise for at least 20 min twice per week at the time they were seen in the clinic and only a small number were currently engaged in a pain management psychology or cognitive behavioral therapy program run by a trained therapist. Complementary or alternative therapies were being used regularly at least once a month for the past 3 months by almost half the patients at the time of the clinic visit but had been used by over three-quarters of patients for their fibromyalgia symptoms at any time. Examples of these therapies include natropathy, chiropractic treatment, osteopathy, myotherapy, acupuncture, Bowen therapy and tai chi. Differences in clinical measures between patients based on treatment at time of presentation are shown in Table 5. Patients who were already using one of the three previously listed drugs (low dose tricyclic antidepressant, pregabalin or duloxetine) for fibromyalgia symptoms at time of presentation had lower mean levels of anxiety (P = 0.06) and higher reported physical function (P = 0.04) than those who were not using these medications. Patients already maintaining a regular exercise program when first seen in the clinic had reduced overall illness impact scores (P = 0.004), better physical function (P = 0.01), and less fatigue (P = 0.03), anxiety (P = 0.02) and depressive features (P = 0.008) than non-exercisers. Patients who had received pain management psychological counseling at any stage, were no different from those who had not, when comparing mean scores from these clinical measures. Anxiety levels at presentation were lower in people with current use of complementary or alternative therapies (P = 0.04).
DISCUSSION This study produces an overview of patients at their initial visit to an Australian public fibromyalgia clinic. The baseline demographics of age and sex are similar to
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published observations in other populations.34 Patients included in this analysis all had typical clinical features of fibromyalgia, despite 36.3% not having the minimum of 11 tender points at the time of assessment, which are required to satisfy the ACR 1990 classification criteria. These patients were diagnosed on the basis of their broader clinical profile. This reflects current clinical concepts recognized in the ACR 2010 diagnostic criteria33 which take into account the longitudinal clinical variations seen in fibromyalgia. Many were receiving disability, compensation or other pension payments. This may reflect the illness severity of patients referred to a tertiary hospital clinic; however, it may also be an expression of the socioeconomic status of patients using a public outpatient service rather than seeking medical attention in the private health sector. Most patients reported a recognizable factor which was linked to the initiation of their symptoms when directly asked. These triggers predominantly involved psychosocial stress (29.3%), but also included illness (10.7%) and injury (10%). Very often there were combinations of factors contributing to the trigger, a common finding in fibromyalgia sufferers.16 The population of patients seen in this public tertiary hospital outpatient clinic had a long duration of symptoms (mean 10 years) and a high number of comorbid conditions which are considered associations of fibromyalgia. The most common associated conditions in our study population were irritable bowel syndrome and headache (both affected 71.3% of the study population). They have also been identified as common comorbid problems in other large study populations.33 Symptoms relating to these two problems and depression were selected for inclusion in a modification of the new 2010 ACR fibromyalgia diagnostic criteria to be used in clinical and epidemiological studies.35 The overall illness impact scored by our subjects was higher than that recorded by “average” fibromyalgia patients in the literature32; however, FIQ scores in other study patient populations have varied between 44.336 and 67.137. Scores from our patient group were particularly high in the areas of pain, fatigue and sleep disturbance when compared to those found in the original FIQ calibration population,31 although only slightly higher than scores for these variables in a group of 50 patients enrolled in an acupuncture in fibromyalgia study38 and comparable to published scores in a group of 313 subjects enrolled in a medication treatment trial with fibromyalgia.39 This suggests that our patients have illness in the more severe clinical spectrum, but are comparable to other patient research groups. It is likely
International Journal of Rheumatic Diseases 2012
Australian fibromyalgia characteristics
Table 5 Differences in clinical measures of patients based on treatment at time of presentation
Patients not on fibromyalgia drugs (n = 97) Patients on fibromyalgia drugs (n = 51) P-value* Mean difference 95% CI Patients not regularly exercising (n = 84) Patients regularly exercising (n = 64) P-value* Mean difference 95% CI Pain psychology not ever used (n = 103) Pain psychology ever used (n = 45) P-value* Mean difference 95% CI Complementary therapy not currently used (n = 78) Complementary therapy currently used (n = 68) P-value* Mean difference 95% CI
Total FIQ score (/100)
Physical function (/10)
61.7 (13.9)
4.1 (2.2)
6.6 (2.3)
7.8 (1.8)
8.1 (1.8)
6.1 (2.4)
5.0 (2.7)
62.4 (14.9)
4.9 (2.3)
6.9 (2.5)
8.0 (1.8)
8.0 (1.6)
4.7 (3.0)
4.6 (2.8)
0.78 0.7 5.54 4.21 64.8 (13.4)
0.04 0.8 1.54 0.02 4.8 (2.2)
0.50 0.3 1.07 0.53 6.9 (2.2)
0.50 0.2 0.83 0.40 8.1 (1.7)
0.72 0.1 0.48 0.69 8.3 (1.5)
0.006 1.4 0.48 2.28 6.1 (2.6)
0.47 0.4 0.60 1.3 5.4 (2.7)
58.1 (14.5)
3.8 (2.2)
6.4 (2.5)
7.5 (1.8)
7.8 (1.9)
5.0 (2.7)
4.2 (2.8)
0.004 6.7 2.14 11.24 61.3 (13.6)
0.01 1.0 0.19 1.65 4.3 (2.2)
0.16 0.5 0.22 1.32 6.5 (2.4)
0.03 0.6 0.07 1.23 7.8 (1.8)
0.59 0.5 0.02 1.09 8.2 (1.7)
0.02 1.1 0.15 1.89 5.7 (2.7)
0.008 1.2 0.32 2.10 4.9 (2.8)
63.3 (15.6)
4.6 (2.4)
7.2 (2.1)
7.8 (1.8)
7.9 (1.8)
5.4 (2.6)
4.7 (2.8)
0.43 2.0 7.02 3.04 62.8 (14.1)
0.51 0.3 1.06 0.53 4.4 (3.0)
0.07 0.7 1.57 0.07 6.8 (2.4)
0.99 0.0 0.62 0.65 8.0 (1.8)
0.28 0.3 0.27 0.93 8.2 (1.6)
0.47 0.3 0.61 1.31 6.0 (2.6)
0.74 0.2 0.82 1.15 5.3 (2.7)
60.9 (14.2)
4.4 (2.3)
6.6 (2.3)
7.6 (1.8)
8.0 (1.8)
5.1 (2.8)
4.4 (2.8)
0.90 0.0 0.78 0.70
0.55 0.2 0.54 1.01
0.18 0.4 0.19 0.97
0.33 0.2 0.28 0.83
0.04 0.9 0.05 1.81
0.06 0.9 0.03 1.77
0.42 1.9 2.73 6.55
Pain (/10)
Fatigue (/10)
Sleep (/10)
Anxiety (/10)
Depressive features (/10)
Values reported as mean (SD). *P-value indicates significance of difference between patients using the treatment and those not using the treatment. Multiple regression analyses to predict change in clinical measures were performed using variables identified as significant in correlation analyses.
that more straightforward patients are successfully managed by their local doctor, while those with chronic, entrenched symptoms and poor response to previous management approaches are referred on to a specialized clinic. When considering management modalities, we found that < 35% of patients were currently using either lowdose tricyclic antidepressant, duloxetine or pregabalin at time of presentation to the clinic. This is perhaps not surprising as the use of these medications for the management of fibromyalgia symptoms required off-label
International Journal of Rheumatic Diseases 2012
prescription, as there were no medications approved for use in fibromyalgia management by the Therapeutic Goods Administration of Australia at the time this study was conducted. Interestingly, those patients who were using these agents at their first visit had lower levels of anxiety and better physical function than those who were not. Regular exercise has the capacity to improve fibromyalgia symptoms, as concluded in a large meta-analysis.40 There is no published data in an Australian population. However, exercise was being performed by
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less than half of the patients on presentation in this study. Understandably this is a difficult management modality for many fibromyalgia sufferers to commence and maintain; however, given the potential benefits of such a program and the problematic accessibility of pharmacotherapy for this condition at the time this data was collected, exercise remains the one easily used therapy with proven benefits available to Australian patients.40 The finding that a minority (43.6%) of patients were regularly exercising, particularly in the group satisfying ACR 1990 criteria who had more severe clinical characteristics, may result from a lack of patient education regarding the proven benefits of exercise for fibromyalgia. It seems more likely that this group of patients with severe, long-standing illness has found either the initiation or continuance of physical activity on a regular basis too difficult due to high pain and fatigue levels. It was certainly notable that the group of patients who were performing regular exercise had lower overall illness impact, better physical function and lower levels of fatigue, anxiety and depression than those who were not. It is unclear whether this group was able to maintain their exercise because they had milder symptoms, or whether they were experiencing significant benefit from the activity. The low numbers of patients performing regular physical exercise, associated with other possible poor health practices, may account for the mean BMI being in the overweight range in this group. The small numbers (45 individuals) may explain why patients who had been involved in pain management psychology programs showed no differences in clinical measures when compared with those who were not involved in such programs. It is noted that not all of our patient population met the 1990 ACR classification criteria, which possibly influenced this result. It is also possible that the psychological programs used in clinical trials28,41 which showed proven benefit in fibromyalgia were more specifically tailored than those available to most of the patients seen in our clinic. Complementary or alternative therapies had been used by a significant majority of patients. Although there was no difference seen between those using these modalities and those who were not in nearly all clinical measures, the fact that over three-quarters had tried them probably reflects the lack of satisfaction experienced by fibromyalgia sufferers with the complexity of fibromyalgia symptoms, their illness impact and often poor engagement by the general medical community. Anxiety levels were reported as lower in the patient group who were currently using complementary or alternative
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therapy (P = 0.04), and this may relate to an increased sense of control in people who were actively seeking different ways to impact on their illness. Physical function, pain, fatigue and sleep disturbance are key clinical domains of fibromyalgia. These all contribute to the overall impact of the illness and are some of the areas in which fibromyalgia patients would most like to see improvement.42 Relationships between these illness features and other patient characteristics showed a number of significant associations. Physical function was significantly predicted by levels of reported pain. In our study population, it would be interesting to see if improvement in pain results in more physical function gain, even if fatigue and sleep disturbance are still problematic. There was no relationship found in this analysis between physical function, and fatigue, sleep disturbance or depressive features, despite these factors being commonly reported as interfering with quality of life. The finding that fatigue was positively associated with younger age (P < 0.05) has not been previously described. It is possible that illness expression is different in those of younger age, or that younger people expect to have higher than usual energy levels in keeping with their peers. The significance of this finding requires more specific study. The limitations of this study include the fact that this data was obtained from a single visit by patients to a single tertiary hospital clinic. The data may not be representative of the clinical spectrum of all patients being seen throughout Australia as it does not include people managed in the primary care setting, those in a rural environment, or those managed in secondary or tertiary private care settings. It is important in the future for there to be a wider scope and larger amount of data collected from patients with this condition. There are still no incidence or prevalence figures for the Australian population, nor do we have any data about change over time or societal impact. Much work needs to be done to gather information in these and other areas before we can have a clear idea of the health impact of this disorder in Australia.
CONCLUSION Fibromyalgia is a problematic chronic illness with serious impact on the well-being of patients, as well as their wider communities. We have reported on the baseline clinical characteristics of patients being seen at first visit in an Australian public hospital outpatient fibromyalgia clinic. These were people with similar demographic characteristics to those found in other reported
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Australian fibromyalgia characteristics
populations; however, the duration of the illness was long and its clinical characteristics seemed severe. In these patients, the use of management modalities with known clinical benefit in fibromyalgia was limited, despite their long history of illness, and often multiple encounters with healthcare providers. It is unclear whether this reflects the level of understanding regarding the optimal management of this condition in the local healthcare community, or is a reflection of a more difficult patient group seen in this clinic. These data provide some insight into the characteristics of patients with fibromyalgia in an Australian population; however, much more needs to be done in order to build an accurate picture of the scope and impact of this illness in Australia.
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ACKNOWLEDGMENTS No specific funding was sourced for this project. We would like to thank Kathleen Elford for managing the fibromyalgia clinic and for her help in collecting and entering data. Emma Guymer and Geoffrey Littlejohn have received consultancy fees from Pfizer and Lilly, and they and their institution have been involved in clinical trials of pregabalin and duloxetine.
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AUTHOR CONTRIBUTIONS
14
EG was involved with the original concept, planning the study, overseeing patient contact, analysis and preparing a manuscript. GL was involved with the original concept, planning the study and preparing a manuscript. PM was involved in analysis and preparing a manuscript.
15
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