Objective: To examine the predictors of time-to-premature gonadal failure (PGF) in SLE patients from LUMINA, a multiethnic US cohort.
Methods: PGF was defined as per the SLICC Damage Index (SDI). Factors associated with time-to-PGF occurrence were examined by univariable and multivariable [three models according to cyclophosphamide use, at T0 (model 1), over time (model 2) and the total number of intravenous pulses (model 3)] Cox proportional hazards regression analyses.
Results: Thirty-seven of 316 women (11.7%) developed PGF (19 Hispanic-Texans, 14 African Americans, four Caucasians and no Hispanic-Puerto Ricans). By multivariable analyses, older age at T0 (HR=1.10 to 1.14; 95% CI 1.02 to 1.05-1.19 to 1.23) and disease activity (SLAM-R) in all models (HR=1.22 to 1.24; 95% CI 1.10 to 1.12-1.35 to 1.37), Hispanic-Texan ethnicity in models 2 and 3 (HR=4.06 to 5.07; 95% CI 1.03 to 1.25-15.94 to 20.47) and cyclophosphamide use in models 1 and 3 (1-6 pulses) (HR=4.01 to 4.65; 95% CI 1.55 to 1.68-9.56 to 13.94) were predictors of a shorter time-to-PGF.
Conclusions: Disease activity and Texan-Hispanic ethnicity emerged as predictors of a shorter time-to-PGF while the associations with cyclophosphamide use and older age were confirmed. Furthermore, cyclophosphamide induction therapy emerged as an important determinant of PGF.