The clinical characteristics and significance of novel inflammatory biomarkers in patients with polymyalgia rheumatica: A single-center study from China.

OBJECTIVE

Polymyalgia rheumatica (PMR) is an inflammatory rheumatic disorder predominantly affecting older adults, characterized by proximal muscle pain and stiffness. The prevalence of PMR in Chinese population is relatively low comparing to European population, resulting in limited research regarding its clinical manifestations and serological characteristics among Chinese patients. We aimed to analyse the features of Chinese patients with PMR and explore the significance of novel inflammatory biomarkers.

METHODS

We retrospectively collected the medical data of hospitalized patients diagnosed with PMR at Peking University People's Hospital between 1992 and 2022. Electronic medical records were reviewed. We analyzed the clinical and laboratory characteristics of patients with PMR, and explored new inflammatory markers.

RESULTS

A total of 87 patients were included in the study, with a male-to-female ratio of 1:2.6. The most common clinical manifestation was shoulder girdle pain (96.6 %), followed by pelvic girdle pain (89.7 %), cervical spine pain (63.2 %), morning stiffness (48.3 %), and lumbar spine pain (40.2 %). Cervical spine pain was more common in female patients than in male patients. 12 out of 87 (13.8 %) patients with PMR were complicated with giant cell arteritis (GCA). Anorexia was more commonly seen in patients with GCA (P = 0.024). IL-6 was the most frequently elevated cytokine and was significantly associated with fever. The systemic immune-inflammation index (SII), platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) were correlated with C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR).

CONCLUSION

Shoulder girdle and pelvic girdle pain were the most common manifestations of PMR. 13.8 % of the patients had concurrent GCA. Elevated levels of IL-6 were significantly correlated with fever, indicating that IL-6 may contribute to the systemic inflammation of PMR. SII, NLR and PLR were positively associated with the levels of ESR and CRP, suggesting that these novel markers are promising inflammatory markers in patients with PMR.