Patients with rheumatoid arthritis (RA) receiving glucocorticoids at an average dose of ≥3.25 mg/d are at higher risk of developing sarcopenia, according to research results published in Clinical Rheumatology.
Researchers conducted a prospective, single-center observational study, Correlation Research of Sarcopenia, Skeletal Muscle, and Disease Activity in Rheumatoid Arthritis (CHIKARA), to examine the correlation between sarcopenia and disease activity in RA and to determine the predictors or risk factors for sarcopenia development.
The study cohort included 100 consecutive patients with RA (78 women) from a single institution, all of whom fulfilled the 2010 American College of Rheumatology/European League Against Rheumatism classification criteria. Five patients were lost to follow-up at 1 year, resulting in a total cohort of 95 patients (median age, 66.0 years; 80.9% women; median disease duration, 5.7 years).
In total, 27 patients had sarcopenia at baseline; about one-third presented with advanced joint destruction (Steinbrocker stage 3 or 4) and almost all patients maintained higher functional activity (Steinbrocker functional class 1 or 2) with a median modified Health Assessment Questionnaire (HAQ) score of 0.25 and moderate disease activity. Most patients (89.6%) were treated with methotrexate, 29.4% with glucocorticoids, and 33.8% with biologic disease-modifying antirheumatic drugs (DMARDs), including golimumab, tocilizumab, infliximab, abatacept, etanercept, adalimumab, and certolizumab pegol, or targeted synthetic DMARDs.
Nine of the 68 patients without sarcopenia at baseline developed sarcopenia during the course of 1 year. Compared with patients without sarcopenia, those who developed sarcopenia were significantly older (66 vs 76 years, respectively; P =.024) and had a lower body mass index (20.8±2.1 vs 23.2±3.4 kg/m2; P =.040) and body fat mass (11.7±3.8 vs 17.6±6.9 kg/m2; P =.015). Compared with patients without sarcopenia, those who developed sarcopenia received glucocorticoid medications more frequently (25.4% vs 55.6%); however, there was no significant difference between the 2 groups (P =.064).
Univariate analysis indicated that age, average glucocorticoid dose, body fat mass, and ΔC-reactive protein were significantly associated with sarcopenia development, although these associations were not strong. Baseline glucocorticoid dose and modified HAQ scores tended to be associated with sarcopenia development, but Disease Activity Score in 28 joints-Erythrocyte Sedimentation Rate (DAS28-ESR), ΔDAS28-ESR, methotrexate use, and biologic DMARD use demonstrated no associations.
Analysis of the receiver operating characteristic (ROC) curve for average glucocorticoid dose during the year showed that the cutoff glucocorticoid dose was 3.25 mg/d (area under the ROC curve, 0.67; 95% CI, 0.47-0.86). Results of a multivariate logistic analysis demonstrated that glucocorticoid use of ≥3.25 mg/d (odds ratio, 8.81; 95% CI, 1.14-67.9; P =.037) was a significant factor in sarcopenia development when age, average glucocorticoid use, modified HAQ score, and DAS28-ESR were used as explanatory variables.
Study limitations included potential selection bias and a small number of new sarcopenia cases because of the small number of study participants and the short-term follow-up.
“The present study showed that average [glucocorticoid] dose ≥3.25 mg/[d] over the year was an independent risk factor for developing sarcopenia in patients [with] RA,” the researchers concluded. “Reduction or withdrawal of [glucocorticoids], as well as controlling disease activity by the [treat-to-target] concept, may prevent development.”
Yamada Y, Tada M, Mandai K, Hidaka N, Inui K, Nakamura H. Glucocorticoid use is an independent risk factor for developing sarcopenia in patients with rheumatoid arthritis: From the CHIKARA study [published online January 14, 2019]. Clin Rheumatol. doi:10.1007/s10067-020-04929