Relationship between surfactant proteins B and C and obstructive sleep apnea: is serum SP-B concentration a potential biomarker of obstructive sleep apnea?

Background: Surfactant proteins B and C are mainly synthesized, secreted by alveolar type II cells, and affected by hypoxia and mechanical stretches. We hypothesized that their serum levels might be altered by intermittent hypoxia and swing of intrathoracic pressure of obstructive sleep apnea (OSA).

Methods: Consecutive 140 middle-aged males, suspicious of OSA determined by polysomnography, were studied.

What do changes in concentrations of serum surfactant proteins A and D in OSA mean?

Purpose: Previous studies have shown that surfactant proteins are affected by oxygen concentration and mechanic stretches, although the alteration of serum surfactant proteins in individuals with obstructive sleep apnea (OSA) is still unclear. Therefore, the aim of this study is to examine whether serum concentrations of surfactant proteins A and D are altered and related to hypopnea index (HI) in OSA.

Methods: This is a cross-sectional study.