Background In recent decades, there is an advancement in systemic lupus erythematosus (SLE) therapy and survival rates, however morbidity caused by organ damage remain problematical. The aims of this study were to evaluate the irreversible damage resulting from systemic lupus erythematosus (SLE) disease activity and its treatment by using Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) Damage Index (SDI) and to establish factors that influence damage in SLE.

Methods Two hundred-eleven SLE patients were included in a retrospective cohort study. Participants were divided into 2 groups, SDI = 0 (without damage) or SDI ≥ 1 (with damage), then the two groups were compared using factors that affecting SDI. Statistical analysis was by chi2 test, Fisher’s exact test, Mann-Whitney test, and multivariable logistic regression.

Results There were 127 (61.2%) participants who had damage index ≥ 1. Most of the participants had renal damage (29.38%), followed by neuropsychiatric damage (14.69%) and ocular damage (14.22%). Factors that significantly associated with damage were relapse rate ≥ 1 (p<0.001), hypertension (p=0.007), exposure to cyclophosphamide (p<0.001), mycophenolic acid (p=0.016), high serum creatinine (p=0.003) and positive protein urine (p<0.005). By using multivariable logistic regression, we found that, relapse rate ≥ 1 (p=0.008, OR 2.414 (1.255–4.642)), High serum creatinine (p=0.034, OR 9.573 (1.192–76.852)) and exposure to cyclophosphamide (p=0.017, OR 2.926 (1.213–7.057)) were significantly associated with damage.

Conclusions Damage in SLE is significantly associated with relapse rate and high serum creatinine suggesting that controlling disease activity to prevent relapse and comorbidity is very important to prevent further damage. This study also reveals that cyclophosphamide administration was associated with increased risk of damage, probably related to the more active organ involvement (renal and cerebral) who received cyclophosphamide.