Prevalence of sarcopenia and its association with clinical features and health-related quality of life in Brazilian women with systemic lupus erythematosus.

OBJECTIVES

To assess the prevalence of sarcopenia and examine its association with clinical features, health-related quality of life (HRQoL), muscle-specific strength and body composition in patients with systemic lupus erythematosus (SLE).

METHODS

In this cross-sectional multicentre study, women with SLE (18-50 years old) were included. Data collected included clinical features and HRQoL. Muscle strength was assessed using the handgrip test (kg), appendicular skeletal muscle mass index (ASMI, kg/m²) was measured using dual-energy X-ray absorptiometry. Physical performance was assessed using the timed-up-and-go test (TUG, seconds). Sarcopenia was defined by the European Working Group on Sarcopenia in Older People-2 criteria. The muscle-specific strength was evaluated by dividing their arm strength by their lean arm mass. Pearson's or Spearman's correlation coefficients were performed (accepted at p<0.05).

RESULTS

Seventy-three SLE women were included, with median (IQR) age and disease duration of 37 (30-44) years old and 10.0 (4.0-16.8) years, respectively. Most of the patients (83.5%) had inactive or low disease activity and 31.0% presented a disease damage index score ≥1. Mean (±SD) handgrip strength, ASMI and muscle-specific strength was 25.58±8.31 kg, 6.62±0.97 kg/m² and 6.6±2.3, respectively. Median TUG was 6.9 (6.1-8.2) s. The prevalence of probable sarcopenia was 11.1%, and sarcopenia was 2.7%. Lower muscle strength, lower muscle-specific strength and lower physical performance, as well as sarcopenia, were correlated with worse HRQoL (p<0.05).

CONCLUSION

In Brazilian patients with SLE with inactive or low disease activity, the prevalence of sarcopenia was low. However, low muscle strength, low muscle-specific strength and low physical performance were correlated with worse HRQoL, emphasising the need for muscle strength assessments in SLE management.