Sex-based clinical and immunological differences across lupus erythematosus subtypes: a cross-sectional multicentre study from China.

OBJECTIVE

To investigate sex-related differences in clinical and immunological features across lupus erythematosus (LE) subtypes.

METHODS

This cross-sectional analysis, based on the Lupus Erythematosus Multicenter Case-Control Study in Chinese populations (ChiCTR2100048939), included patients with SLE and major cutaneous LE (CLE) subtypes. Sex-specific comparisons were performed using R V.4.4.2.

RESULTS

In 2097 patients (1865 SLE, 1648 CLE), female predominance was observed in all subtypes, with female-to-male ratios ranging from 11.3:1 (acute CLE, ACLE) to 2.1:1 (isolated CLE, iCLE). Except for ACLE, females had earlier or similar onset than males in all other subtypes. ACLE lesions were most common in females (67%). In male patients with LE, the proportion of discoid LE (DLE) lesions was higher than female patients (31% vs 12%). Compared with males, females exhibited higher frequencies of arthritis in SLE, ACLE, DLE and chilblain LE (CHLE). In DLE, renal involvement, haematological abnormalities and serositis were more frequently observed in females. In subacute CLE (SCLE), haematological abnormalities were significantly more common in females. Additionally, non-scarring alopecia was more common in females than in males. Females had higher autoantibody positivity in iCLE and chronic CLE, with significant differences in anti-double-stranded DNA, anti-Smith, anti-U1-nuclear ribonucleoprotein and anti-ribosomal P antibodies.

CONCLUSIONS

Across the subtypes, several clinical manifestations show a consistent sex distribution: ACLE lesions, arthritis, non-scarring alopecia, Raynaud's phenomenon and autoantibodies occur more frequently in women with LE, whereas the proportions of DLE and SCLE lesions are higher in men with LE. In addition, certain features exhibit subtype-specific sex differences: among patients with SCLE, DLE and CHLE, women show a greater propensity for systemic involvement, whereas in those with SLE and ACLE, men demonstrate a higher tendency toward systemic disease.

TRIAL REGISTRATION NUMBER: ChiCTR2100048939.