Obesity increases the incidence of new-onset lupus nephritis and organ damage during follow-up in patients with systemic lupus erythematosus

Abstract

Objective This study explored the effects of obesity on clinical manifestations, disease activity and organ damage in Korean patients with systemic lupus erythematosus (SLE). Methods We assessed 393 SLE patients annually for three consecutive years based on demographic information, clinical manifestations, laboratory findings and Physician Global Assessment, Systemic Lupus Erythematosus Disease Activity Index (SLEDAI)-2000 and Systemic Lupus International Collaborating Clinics (SLICC) damage index (SDI) scores. Patients were grouped by body mass index (BMI): normal weight, BMI <23 kg/m2; overweight, 23 kg/m2 ≤BMI <25 kg/m2; obese, BMI ≥25 kg/m2. The impact of obesity on clinical outcomes was assessed using univariate and multivariate analyses. Results Of the 393 patients, 59 (15.0%) were obese at enrollment. They had more comorbidities compared with non-obese patients, including diabetes, hypertension, hyperlipidemia and pulmonary hypertension. Nephritis at enrollment and newly developed nephritis during follow-up were more common ( p = 0.002 and p = 0.002, respectively) and Physician Global Assessment and SDI scores were higher in these patients for three consecutive years ( p = 0.017 and p = 0.039, respectively). Multivariate analysis revealed that obesity was significantly associated with development of nephritis during follow-up (odds ratio = 26.636; 95% confidence interval, 11.370–62.399; p < 0.001) and cumulative organ damage (odds ratio = 4.096; 95% confidence interval, 2.125–7.894, p < 0.001). Conclusions The incidences of newly developed nephritis and cumulative organ damage were higher in obese SLE patients than in non-obese SLE patients.