Association between circulating leptin levels and multiple sclerosis: a systematic review and meta-analysis

Area of Science:

• Immunology and Neuroscience
• Endocrinology and Metabolism

Background:

• Leptin, a hormone produced by adipocytes, modulates inflammatory activity.
• Previous studies on leptin levels in multiple sclerosis (MS) patients yielded inconsistent results.
• Understanding the relationship between leptin and MS is crucial for disease pathogenesis research.

Purpose of the Study:

• To conduct a meta-analysis to precisely evaluate the association between circulating leptin levels and MS.
• To synthesize existing evidence regarding leptin's role in MS.

Main Methods:

• A comprehensive literature search was performed up to July 2017.
• A random-effect model was employed to calculate the pooled standardized mean difference (SMD) and 95% confidence interval (CI).
• Included 9 studies comprising 645 patients with MS and 586 healthy controls.

Main Results:

• Patients with MS exhibited significantly higher plasma/serum leptin levels compared to healthy controls (SMD = 0.70, 95% CI: 0.24 to 1.15).
• Subgroup analyses indicated that leptin levels in MS patients were influenced by factors including region, age, sample size, measurement type, gender, and blood sample type.
• The meta-analysis included 9 studies after screening 2155 identified studies.

Conclusions:

• This meta-analysis suggests a significant elevation in leptin levels among patients with MS compared to healthy individuals.
• Further research, including mechanistic and longitudinal cohort studies, is warranted to elucidate leptin's precise role in MS pathogenesis.
• The findings highlight leptin as a potential biomarker or therapeutic target in MS.