Predictors of Hand Contracture in Early Systemic Sclerosis and the Effect on Function: A Prospective Study of the GENISOS Cohort.

OBJECTIVE

To identify baseline features that predict progression of hand contractures and to assess the effect of contractures on functional status in the prospective GENISOS cohort.

METHODS

Rate of decline in hand extension, as an indicator of hand contracture, was the primary outcome. We assessed longitudinal hand extension measurements, modified Health Assessment Questionnaire (MHAQ) score, Medical Outcomes Study Short Form-36 (SF-36) physical function score, and demographic, clinical, and serological variables. Subjects with ≥ 2 hand measurements at least 6 months apart were included.

RESULTS

A total of 1087 hand measurements for 219 patients were available over an average of 8.1 ± 4.8 years. Hand extension decreased on average by 0.11 cm/year. Antitopoisomerase I antibody (ATA) positivity and higher modified Rodnan Skin Score (mRSS) were predictive of faster decline in hand extension (p = 0.009 and p = 0.046, respectively). In a subgroup analysis of 62 patients with ≤ 2 years from SSc onset, ATA and diffuse disease type were associated with faster decline in hand extension; anticentromere positivity was associated with slower rate of decline. Although the rate of decline in patients with disease duration ≤ 2 years was numerically higher, the difference was not statistically significant. Hand extension continued to decline in a linear fashion over time and was inversely related to overall functional status.

CONCLUSION

ATA was predictive of contracture development in both early disease (≤ 2 yrs) and in the overall cohort. Hand extension declined linearly over time and was inversely associated with MHAQ and SF-36 scores. ATA positivity and higher baseline mRSS were predictive of faster decline in hand extension.