Evaluation of Plasma/Serum Adiponectin (an Anti-Inflammatory Factor) Levels in Adult Patients with Obstructive Sleep Apnea Syndrome: A Systematic Review and Meta-Analysis

Amir Najafi; Iman Mohammadi; Masoud Sadeghi; Annette Beatrix Brühl; Dena Sadeghi-Bahmani; Serge Brand

doi:10.3390/life12050738

Evaluation of Plasma/Serum Adiponectin (an Anti-Inflammatory Factor) Levels in Adult Patients with Obstructive Sleep Apnea Syndrome: A Systematic Review and Meta-Analysis

Life (Basel). 2022 May 16;12(5):738. doi: 10.3390/life12050738.

Authors

Amir Najafi¹, Iman Mohammadi¹, Masoud Sadeghi², Annette Beatrix Brühl³, Dena Sadeghi-Bahmani^{3

4

5}, Serge Brand^{3

5

6

7

8}

Affiliations

¹ Oral and Maxillofacial Surgery Department, School of Dentistry, Isfahan University of Medical Sciences, Isfahan 8174673461, Iran.
² Department of Biology, Science and Research Branch, Islamic Azad University, Tehran 1477893855, Iran.
³ Center for Affective, Stress and Sleep Disorders, University of Basel, Psychiatric Clinics, 4001 Basel, Switzerland.
⁴ Department of Psychology, Stanford University, Stanford, CA 94305, USA.
⁵ Sleep Disorders Research Center, Kermanshah University of Medical Sciences, Kermanshah 6719851115, Iran.
⁶ Substance Abuse Prevention Research Center, Kermanshah University of Medical Sciences, Kermanshah 6715847141, Iran.
⁷ Department of Sport, Exercise and Health, Division of Sport Science and Psychosocial Health, University of Basel, 4052 Basel, Switzerland.
⁸ School of Medicine, Tehran University of Medical Sciences, Tehran 1416753955, Iran.

Abstract

Background and objective: A variety of diseases, including obesity, type ‖ diabetes, and cardiovascular diseases are associated with obstructive sleep apnea syndrome (OSAS), and decreased adiponectin levels have been shown to be associated with an increased risk of these diseases. However, the association of blood levels of adiponectin in OSAS patients is a challenging and unknown issue with conflicting results. Therefore, we performed a systematic review and a meta-analysis to evaluate plasma/serum adiponectin levels in adult patients with OSAS. Materials and methods: A comprehensive search in four databases (PubMed/Medline, Web of Science, Scopus, and Cochrane Library) was performed in literature dated older than 12 March 2022, to retrieve the relevant articles. Effect sizes were calculated to show the standardized mean difference (SMD) along with a 95% confidence interval (CI) of plasma/serum of adiponectin between the OSAS patients and controls. The software RevMan 5.3, NCSS 21.0.2, CMA 2.0, trial sequential analysis (TSA) 0.9.5.10 beta, and GetData Graph Digitizer 2.26 were used for data synthesis in the meta-analysis. Results: A total of 28 articles including 36 studies were entered into the meta-analysis. The results showed that pooled SMD was −0.71 (95% CI: −0.92, 0.50; p < 0.00001; I2 = 79%) for plasma/serum levels of adiponectin in OSAS cases compared to the controls. The subgroup analyses showed that the geographical region and the Apnea-Hypopnea-Index (AHI) could be confounding factors in the pooled analysis of plasma/serum adiponectin levels. The sensitivity analysis showed the stability of the results. The radial and L’Abbé plots confirmed evidence of heterogeneity. Trial sequential analysis showed sufficient cases in the meta-analysis. Conclusions: With sufficient cases and stable results, the main finding of the meta-analysis identified significantly reduced plasma/serum levels of adiponectin in OSAS cases compared with the controls. This result suggests a potential role of adiponectin in the pathogenesis of OSAS.

Keywords: adiponectin; meta-analysis; obstructive sleep apnea syndrome; plasma; serum.

Publication types

Review

Grants and funding

This research received no external funding.