Abstract
Background/Purpose: The ACR 1990 diagnostic criteria for fibromyalgia includes a definition for chronic widespread pain (CWP) that depends on a particular distribution of pain sites. The new proposed ACR 2010 criteria instead has a Widespread Pain Index which takes into account the number of sites only. The purpose of this analysis was to see, amongst persons reporting multi-site pain, if the distribution of pain sites has any association with a number of potential risk markers after adjustment for the number of sites.
Methods: The MUSICIAN survey was a general population survey aimed at identifying people with CWP for an intervention study. A questionnaire was sent by post to adults registered at family doctors in two areas of the United Kingdom. Questions included age, gender, employment status, smoking behaviour, height, weight, and questions on pain included a manikin in 35 sections to indicate the location of the pain. Respondents were included in the analysis who indicated that they had between 3 and 16 areas of pain, and that the pain had lasted 3 months or more. (People with less than 3 sites could not meet the ACR 1990 definition of widespread pain, while most of those with more than 16 sites did). Participants were classed as having pain that was widespread or not according to the ACR 1990 criterion. A number of potential associations with having widespread pain were tested using logistic regression to provide odds ratios (OR) with 95% confidence intervals (CI). These models were then adjusted for number of pain sites to see if any associations with the distribution pattern remained after accounting for having pain in multiple areas.
Results: 14680 people responded to the questionnaire, of which 7536 reported some chronic pain (prevalence 51.3%). In those with chronic pain, the median number of pain sites was 5 (interquartile range 3 to 9), and the prevalence of pain that met the ACR 1990 criterion for being widespread was 32.1%. Included in the analysis were 5715 respondents with chronic pain in 3 to 16 areas, of which 2037 (35.6%) met the criterion for widespread pain. Gender age, smoking and employment status all had significant associations with ACR 1990 widespread pain (see table). After adjustment for number of pain sites most of these associations either became non-significant or were attenuated.
Conclusion: We have shown that when number of pain sites was taken into account, the particular distribution of sites did not continue to have significant relationships with many associated factors. This might indicate that is not so much that the pattern of pain locations that is important as the multiplicity of areas. This may have implications in conditions such as fibromyalgia where pain across multiple areas is involved. Based on this data, the use of a measure that looks at the number of pain sites rather than a particular distribution is acceptable as a diagnostic criterion.
Not widespread Widespread Unadjusted Adj for no. of sites
Number Percentage Number Percentage OR 95% CI OR 95% CI
Gender
Male 1600 68.0% 754 32.0% 1 1
Female 2078 61.8% 1283 38.2% 1.31 1.17-1.46 1.13 0.98-1.30
Age
Under 40 495 61.0% 317 39.0% 1 1
40-49 647 63.6% 370 36.4% 0.89 0.74-1.08 0.90 0.71-1.14
50-59 821 65.8% 426 34.2% 0.81 0.67-0.97 0.81 0.65-1.02
60-69 822 63.3% 476 36.7% 0.90 0.75-1.08 0.85 0.68-1.07
Over 70 893 66.6% 448 33.4% 0.78 0.65-0.94 0.77 0.62-0.97
Smoking
Never smoked 1951 65.7% 1019 34.3% 1 1
Ex-smoker 1198 64.6% 657 35.4% 1.05 0.93-1.19 0.87 0.74-1.01
Current smoker 466 58.6% 329 41.4% 1.35 1.15-1.59 1.09 0.89-1.33
Employment
Full-time 1369 66.3% 696 33.7% 1 1
Part-time 533 66.8% 265 33.2% 0.98 0.82-1.16 0.84 0.67-1.04
Retired 1272 65.3% 677 34.7% 1.05 0.92-1.19 0.85 0.71-0.996
Unable to work 169 49.1% 175 50.9% 2.04 1.62-2.56 0.77 0.56-1.04
Student 26 54.2% 22 45.8% 1.66 0.94-2.96 1.32 0.64-2.73
Unemployed 34 53.1% 30 46.9% 1.74 1.05-2.86 1.42 0.74-2.71
Other 229 61.1% 146 38.9% 1.25 0.9996-1.57 0.93 0.70-1.24
BMI
Under 20 163 59.9% 109 40.1% 1.20 0.94-1.57 1.10 0.80-1.52
20-25 1291 64.5% 711 35.5% 1 1
25-30 1388 66.1% 713 33.9% 0.93 0.82-1.06 0.82 0.70-0.97
30-35 494 62.9% 291 37.1% 1.07 0.90-1.27 0.93 0.75-1.16
35 and over 342 61.6% 213 38.4% 1.13 0.93-1.37 0.83 0.65-1.07
Methods: The MUSICIAN survey was a general population survey aimed at identifying people with CWP for an intervention study. A questionnaire was sent by post to adults registered at family doctors in two areas of the United Kingdom. Questions included age, gender, employment status, smoking behaviour, height, weight, and questions on pain included a manikin in 35 sections to indicate the location of the pain. Respondents were included in the analysis who indicated that they had between 3 and 16 areas of pain, and that the pain had lasted 3 months or more. (People with less than 3 sites could not meet the ACR 1990 definition of widespread pain, while most of those with more than 16 sites did). Participants were classed as having pain that was widespread or not according to the ACR 1990 criterion. A number of potential associations with having widespread pain were tested using logistic regression to provide odds ratios (OR) with 95% confidence intervals (CI). These models were then adjusted for number of pain sites to see if any associations with the distribution pattern remained after accounting for having pain in multiple areas.
Results: 14680 people responded to the questionnaire, of which 7536 reported some chronic pain (prevalence 51.3%). In those with chronic pain, the median number of pain sites was 5 (interquartile range 3 to 9), and the prevalence of pain that met the ACR 1990 criterion for being widespread was 32.1%. Included in the analysis were 5715 respondents with chronic pain in 3 to 16 areas, of which 2037 (35.6%) met the criterion for widespread pain. Gender age, smoking and employment status all had significant associations with ACR 1990 widespread pain (see table). After adjustment for number of pain sites most of these associations either became non-significant or were attenuated.
Conclusion: We have shown that when number of pain sites was taken into account, the particular distribution of sites did not continue to have significant relationships with many associated factors. This might indicate that is not so much that the pattern of pain locations that is important as the multiplicity of areas. This may have implications in conditions such as fibromyalgia where pain across multiple areas is involved. Based on this data, the use of a measure that looks at the number of pain sites rather than a particular distribution is acceptable as a diagnostic criterion.
Not widespread Widespread Unadjusted Adj for no. of sites
Number Percentage Number Percentage OR 95% CI OR 95% CI
Gender
Male 1600 68.0% 754 32.0% 1 1
Female 2078 61.8% 1283 38.2% 1.31 1.17-1.46 1.13 0.98-1.30
Age
Under 40 495 61.0% 317 39.0% 1 1
40-49 647 63.6% 370 36.4% 0.89 0.74-1.08 0.90 0.71-1.14
50-59 821 65.8% 426 34.2% 0.81 0.67-0.97 0.81 0.65-1.02
60-69 822 63.3% 476 36.7% 0.90 0.75-1.08 0.85 0.68-1.07
Over 70 893 66.6% 448 33.4% 0.78 0.65-0.94 0.77 0.62-0.97
Smoking
Never smoked 1951 65.7% 1019 34.3% 1 1
Ex-smoker 1198 64.6% 657 35.4% 1.05 0.93-1.19 0.87 0.74-1.01
Current smoker 466 58.6% 329 41.4% 1.35 1.15-1.59 1.09 0.89-1.33
Employment
Full-time 1369 66.3% 696 33.7% 1 1
Part-time 533 66.8% 265 33.2% 0.98 0.82-1.16 0.84 0.67-1.04
Retired 1272 65.3% 677 34.7% 1.05 0.92-1.19 0.85 0.71-0.996
Unable to work 169 49.1% 175 50.9% 2.04 1.62-2.56 0.77 0.56-1.04
Student 26 54.2% 22 45.8% 1.66 0.94-2.96 1.32 0.64-2.73
Unemployed 34 53.1% 30 46.9% 1.74 1.05-2.86 1.42 0.74-2.71
Other 229 61.1% 146 38.9% 1.25 0.9996-1.57 0.93 0.70-1.24
BMI
Under 20 163 59.9% 109 40.1% 1.20 0.94-1.57 1.10 0.80-1.52
20-25 1291 64.5% 711 35.5% 1 1
25-30 1388 66.1% 713 33.9% 0.93 0.82-1.06 0.82 0.70-0.97
30-35 494 62.9% 291 37.1% 1.07 0.90-1.27 0.93 0.75-1.16
35 and over 342 61.6% 213 38.4% 1.13 0.93-1.37 0.83 0.65-1.07
| Original language | English |
|---|---|
| Publication status | Published - 2014 |
| Event | 2014 American College of Rheumatology Annual Meeting - Boston, United States Duration: 14 Nov 2014 → 19 Nov 2014 |
Conference
| Conference | 2014 American College of Rheumatology Annual Meeting |
|---|---|
| Country/Territory | United States |
| City | Boston |
| Period | 14/11/14 → 19/11/14 |
Keywords
- pain
- fibromyalgia