The American College of Rheumatology (ACR) released the first-ever classification criteria for polymyalgia rheumatica (PMR), intended to help healthcare providers identify patients with this painful condition. PMR is relatively common, affecting nearly 711,000 Americans aged 50 or older who characteristically experience rapid onset of pain in the shoulders, neck, and hips, along with other inflammatory symptoms not explained by alternate diagnoses. The disorder can be difficult to diagnose and criteria to recognize PMR have not been well-established or tested in the past.
The new PMR criteria published by the ACR in an advance issue of the journal Arthritis & Rheumatism, in collaboration with the European League Against Rheumatism (EULAR), were developed by assessing candidate criteria during a 6-month prospective cohort study of 125 patients with new-onset PMR and 169 non-PMR comparison subjects who had conditions mimicking the disorder [Dasgupta et al. 2012]. A scoring algorithm was developed to distinguish characteristics specific to PMR and, according to classification criteria that emerged, patients aged 50 years and older might be considered as having PMR if they meet all of the following conditions:
- Shoulder pain on both sides.
- Morning stiffness that lasts at least 45 minutes.
- High levels of inflammation measured by protein in blood (eg, C-reactive protein) and erythrocyte sedimentation rate.
- Reported new hip pain.
- Absence of swelling in the small joints of the hands and feet, and absence of positive blood tests for rheumatoid arthritis.
In an accompanying editorial, the authors stress that the recommendations should be recognized as a provisional classification of PMR and not as firm diagnostic criteria [Spiera and Westhovens 2012]. The research on which the criteria are based involved fewer than 300 patients and there was no “gold standard” test of PMR for comparison. An important use of the criteria will be in helping to guide future research, possibly helping to evaluate treatments for PMR. Currently, the disorder is treated with low-dose corticosteroids, such as prednisone, and the new criteria may help to assess the benefits of additional therapies in these patients by ensuring that all patients being evaluated actually have the same condition.
Further validation of the new PMR criteria in groups with more patients, having different inflammatory and noninflammatory pathologies, coming from a variety of settings, and with longer than 6 months' followup, will be helpful. The editorialists caution that the PMR criteria at present may lack adequate specificity or sensitivity to be applied in everyday clinical practice; although, they do concede that such provisional criteria will be considered for use in practice by rheumatologists and also may prove helpful for use by primary care providers who treat patients with suspected PMR.
> Dasgupta B, Cimmino MA, Kremers HM, et al. 2012 Provisional Classification Criteria for Polymyalgia Rheumatica. Arthritis & Rheumatism. 2012(Apr);64(4):943–954 [abstract here].
> Spiera R, Westhovens R. Provisional diagnostic criteria for polymyalgia rheumatica: Moving beyond clinical intuition? Arthritis & Rheumatism. 2012(Apr);64(4):955–957 [access here].
Don’t Miss Out. Stay Up-to-Date on UPDATES!
Register [here] to receive a once-weekly eNotification of new postings.