Circulating leptin and its correlation with rheumatoid arthritis activity: a meta-analysis

Area of Science:

• Immunology
• Endocrinology
• Rheumatology

Background:

• Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by joint inflammation.
• Leptin, a hormone primarily involved in regulating appetite and metabolism, has been implicated in inflammatory processes.
• Understanding the role of leptin in RA pathogenesis is crucial for developing targeted therapies.

Purpose of the Study:

• To investigate the association between circulating leptin levels and rheumatoid arthritis (RA) disease severity.
• To conduct a meta-analysis correlating leptin with established RA disease activity markers.

Main Methods:

• A systematic literature search was performed across Embase, Medline, and the Cochrane Library.
• Meta-analyses were conducted on data from 37 publications, totaling 2,350 RA patients and 1,815 controls.
• Correlations were assessed between leptin levels and Disease Activity Score 28-erythrocyte sedimentation rate (DAS28-ESR) and C-reactive protein (CRP).

Main Results:

• RA patients exhibited significantly higher circulating leptin levels compared to controls (SMD=0.507, p<0.001).
• Elevated leptin levels in RA were consistently observed, irrespective of sample size.
• A statistically significant positive correlation was found between leptin levels and RA disease activity (DAS28-ESR: r=0.247, p=0.003; CRP: r=0.203, p=0.010).

Conclusions:

• Circulating leptin levels are significantly elevated in individuals with rheumatoid arthritis.
• Leptin levels are positively correlated with RA disease activity and inflammation markers.
• These findings highlight leptin's potential role in the pathophysiology of rheumatoid arthritis.