Serum leptin level in the patients with rheumatoid arthritis : as an useful marker for monitoring disease activity

Abstract

[한글]

목적 : 류마티스관절염 환자에서, 혈청 렙틴(leptin)의 류마티스 관절염의 활성도와의 연관성을 조사함으로써, 질병 활성도의 예측인자로서의 역할을 고찰하였다.방법 : 50명의 류마티스관절염 환자가 본 연구에 참여하였고, Disease Activity Score 28 (DAS28)를 이용, 질병의 활성도를 측정하여 DAS28가 3.2를 초과하는 환자군을 활성군으로 규정하였고, 3.2 이하인 환자군을 비활성군으로 규정하였다 (활성군 26명, 비활성군 24명). 체질량지수(Body Mass Index, BMI)와 인슐린저항성의 지표인 Homeostasis Model Assessment index (HOMA-IR)를 계산하였고, 혈청 렙틴, 중성지방, 고밀도 콜레스테롤, ESR, CRP 등을 측정하였다.결과 : 활성군의 혈청 렙틴이 비활성군보다 높게 측정되었고 (14.20 ± 10.92 ng/ml vs 7.00 ± 3.42 ng/ml, p=0.003), 체질량지수에 대해 보정한 혈청 렙틴도 활성군에서 유의하게 높았다 (0.64 ± 0.47 ng m2/ml kg vs 0.34 ± 0.17 ng m2/ml kg, p=0.004). 또한, 혈청 렙틴과 체질량지수에 대해 보정한 혈청 렙틴은 각각, 질병의 활성도를 잘 반영하는 DAS28 (r=0.363, p=0.009 and r=0.368, p=0.009)과 CRP (r=0.433, p=0.002 and r=0.472, p=0.001) 와 정비례관계를 보였다.결론 : 류마티스관절염 환자의 혈청 렙틴은 활성군에서 유의하게 높게 측정되었고, 질병의 활성도와 비례하였다. 따라서 혈청 렙틴은 류마티스관절염 환자의 질병의 활성도를 반영하는 유용한 지표로서 의미가 있다.

[영문]Objectives: To investigate whether serum leptin levels are elevated in patients with active rheumatoid arthritis (RA) and they correlate with disease activity in patients with RA.Methods: Fifty patients with RA were enrolled and their disease activities were assessed using the Disease Activity Score 28 (DAS28). All patients were divided into two groups according to DAS28: active group enrolled 26 patients and inactive group enrolled 24 patients. Body mass index (BMI) and Homeostasis Model Assessment (HOMA) index for insulin resistance were calculated and serum leptin levels were determined using antibody primate radioimmunoassay. Lipid profiles, including triglyceride and high-density lipoprotein-cholesterol levels also were measured.Results: Patients with active RA had significantly higher mean serum leptin level compared to those with inactive disease (14.20 ± 10.92 ng/ml versus 7.00 ± 3.42 ng/ml, p=0.003). Mean leptin levels adjusted to BMI were 0.64 ± 0.47 ng m2/ml kg for active RA group and 0.34 ± 0.17 ng m2/ml kg for inactive RA group, and these levels also exhibited a significant difference between groups (p=0.004). Serum leptin levels and leptin levels adjusted to BMI correlated well with both DAS28 (r=0.363, p=0.009 and r=0.368, p=0.009) and CRP levels (r=0.433, p=0.002 and r=0.472, p=0.001) respectively.Conclusions: Serum leptin levels were significantly elevated in patients with active RA, and correlated well with disease activity. These findings suggest that serum leptin levels might be an useful marker for monitoring disease activity in patients with RA.