The effect of positive pressure ventilation on serum ischemia-modified albumin levels in obese patients with obstructive sleep apnea syndrome.

Introduction: Respiratory abnormalities in obstructive sleep apnea syndrome (OSAS) are corrected with positive pressure ventilation treatments. We investigated the effect of positive airway pressure (PAP) treatment on the serum level of ischemia-modified albumin (IMA), an oxidative stress product, in OSAS patients with higher body mass index (BMI) and indication for PAP treatment.

Materials and methods: Seven consecutive female and 23 male patients with a BMI of ≥30 kg/m2 who were diagnosed as having OSAS according to ICSD3 criteria and were planned for PAP, were included. The Epworth Sleepiness Scale and STOP-Bang Questionnaire were performed. Morning arterial blood gas, hemogram, biochemistry, insulin, and IMA were measured after polysomnography and after three months of PAP.

Result: There were no significant changes in lactate, CRP, and serum electrolyte levels measured before and after PAP, except for potassium. When 30 patients were compared in terms of serum IMA levels at baseline and after treatment, the mean baseline value was 0.56 absorbance units (ABSU), and the 3rd-month follow-up IMA value was 0.53 ABSU (p= 0.537). The mean serum fasting insulin level was 15.85 µIU/mL and 11.6 (p= 0.002) and the mean HOMA index was 4.4 and 3.0 (p= 0.001), respectively.

Conclusions: Serum IMA levels seem not to be an appropriate marker for the evaluation of PAP treatment in OSAS patients with higher BMI. PAP is associated with a decrease in the fasting insulin level, HOMA index, and hematocrit, but not with serum electrolytes except potassium.