Time to Recovery From Proteinuria and Its Related Factors in Patients With Lupus Nephritis

Abstract

Lupus nephritis (LN) is a severe form of systemic lupus erythematosus (SLE) with renal involvement. It affects the kidneys in about 50% of SLE patients. The aim of this study was to assess the evaluation of proteinuria recovery time and its related factors associated with lupus nephritis patients in Urmia-Northwest of Iran. A retrospective cohort study was carried out, in which medical records of 80 patients with systemic lupus nephritis referred to Imam Khomeini university hospital were reviewed. According to these records, the biopsy-proven renal disease has been progressed from September 2009 to September 2013. Proteinuria, less than 0.5 g/24h, was defined as proteinuria recovery. The time elapsed from the diagnosis of proteinuria to its recovery is considered as the duration of proteinuria recovery (month). The findings were analyzed by STATA11 statistical software. The mean age at diagnosis of lupus nephritis was 26.50±8.10 years (14-51 years). The mean creatinine level at the start of treatment was 1.20±0.61 mg/dl (0.5-2.80). Proteinuria recovery time was four months for 25% of patients, six months for 50% of patients (median time), and 12 months for 75% of them. The higher class of LN had a trend toward 31 % lower risk of proteinuria recovery (HR: 0.73, 95% CI 0.56-0.96; P=0.02), the expected risk is 1.94 times greater in women as compared with men (HR: 1.94, 95% CI 1.1-3.48; P=0.02). The patients in this study population respond to treatment in less time, and in comparison with other studies, their proteinuria recovers earlier. Class of lupus nephritis (negative) and gender (positive) were predictive factors of proteinuria recovery among LN patients.