Background Fibromyalgia (FM) is more prevalent than most rheumatic diseases in the general population, and is seen as a secondary phenomenon in 20–40% of people who have inflammatory rheumatic diseases. Formal ACR criteria to identify FM using self-report questionnaire data have been established (1), but generally not applied in busy clinical settings, in which it is not feasible to use multiple different patient questionnaires. A multidimensional health assessment questionnaire (MDHAQ) is feasible for completion by patients in the waiting area, and informative in rheumatoid arthritis (RA) as well as many other rheumatic diseases, and may be useful in FM. (2)
Objectives To develop a cumulative index based on specific cutpoints of individual MDHAQ measures to screen for patients with primary or secondary fibromyalgia in busy clinical settings.
Methods In two rheumatology settings, patients complete an MDHAQ at each visit. Nine MDHAQ scales were analyzed: 0–10 scores for physical function, pain, patient global estimate, and fatigue; 0–3 sores for sleep quality, anxiety, and depression; a RA disease activity index (RADAI) 0–48 self-report painful joint count and symptom checklist of 60 items. Scores on all MDHAQ scales were compared in Setting A in patients with a clinical diagnosis of primary FM vs RA with no secondary FM, and in Setting B in patients who had secondary FM according to ACR FM criteria vs other patients who did not meet ACR FM criteria. Only patients with complete data for all 9 MDHAQ scales and the ACR FM scales in Setting B were included in the study. Comparisons included frequencies, t tests, cross-tabulations with various cut-points, and receiver-operator curves, as well as a kappa statistic comparing clinician diagnosis of secondary FM vs FM by ACR criteria in setting B. A possible cumulative index based on specific cutpoints of individual measures, analogous to RA classification criteria (3), was explored with several cutpoints of different numbers of MDHAQ measures.
Results In Setting A, 286 patients with RA were compared to 195 with FM. In setting B, 22 patients who had other diagnoses but secondary FM by ACR criteria were compared to 68 patients who had no FM by ACR criteria. All 9 MDHAQ scales were significantly higher in patients with FM compared to patients with RA or other diagnoses in both settings according to t tests and receiver-operator curves (data not shown). In Setting B, the kappa statistic was 0.68, indicating >80% agreement between the clinician diagnosis and ACR FM criteria. The highest levels of significance were seen for symptom checklist, RADAI self-report joint count scores, and pain scores. For example, an index provided a clue to primary or secondary FM at either site, with 2 of the following 3 measures: Pain ≥5, RADAI ≥16, symptom checklist ≥16.
Conclusions MDHAQ scales can provide clues to identify primary and secondary FM. Of course, a diagnosis requires a physician history and physical examination, but a screening tool may save time and increase recognition of FM in busy clinical settings.
Disclosure of Interest None declared