Assessment of the role of serum ischemia-modified albumin in obstructive sleep apnea in comparison with interleukin-6

ABSTRACT

Objectives: There is limited and contradictory information regarding the role of serum ischemia-modified albumin (IMA) in obstructive sleep apnea (OSA). In this study we examine the effects of OSA and obesity on IMA and interleukin-6 (IL-6), and detect whether IMA and IL-6 may be potential biomarkers in OSA.

Methods: Fifty-one males who underwent all night polysomnography test were included into the study. Body-mass index (BMI) and apnea-hypopnea index (AHI) of all patients were determined. Serum IMA and IL-6 levels, erythrocyte sedimentation rate (ESR), complete blood count, routine blood biochemistry and thyroid function tests were performed.

Results: Mean IMA [0.36 (± 0.04) U/ml, 0.89 (± 0.15) U/ml], mean IL-6 [1.01 (± 0.19) pg/ml, 2.02 (± 1.19) pg/ml] and mean ESR [4.14 (± 2.5) mm/h, 14.35 (± 13.7) mm/h] levels showed significant difference between non-OSA and OSA groups (P = 0.005, P < 0.001, P < 0.001, respectively). Sensitivity of IMA in distinction of non-OSA/OSA was equal to IL-6 and higher than ESR. IMA was also a stronger predictive factor than IL-6 and ESR in the evaluation of OSA groups (severe/mild/moderate OSA and non-OSA). IMA was the sole distinctive biomarker in assessment of obese and non-obese cases. IMA correlated with IL-6, AHI and ESR.

Conclusion: Serum IMA may be a valuable oxidative stress indicator for OSA and could act as a better biomarker than IL-6 for reflecting the presence and the severity of OSA.

KEYWORDS:

• Biomarker
• interleukin-6
• ischemia-modified albumin
• obesity
• sleep apnea

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.