Ozkok A, et al. - The links between obstructive sleep apnea syndrome (OSAS), heparanase and endothelial dysfunction were investigated in this study. OSAS patients had significantly increased serum heparanase levels, which were found to be related to the severity of OSAS [apnea hypopnea index (AHI)] and endothelial dysfunction (FMD). It was also observed that increased heparanase activity in OSAS may be associated with increased cardiovascular risk in this patient population.

Methods

• This study included a total of 120 patients with varying severity of OSAS and 31 controls without OSAS.
• As an indicator of endothelial dysfunction, flow-mediated dilatation (FMD) was measured.
• Using ELISA, serum heparanase levels were measured.

Results

• In a stepwise fashion, from controls to patients with more severe OSAS, increase in serum heparanase levels was reported.
• Findings also demonstrated that a stepwise decrease in FMD was observed when FMD was compared with controls and various degrees of severity of OSAS.
• In patients with OSAS, it was noted that serum heparanase levels significantly associated with apnea hypopnea index (AHI) (r=0.57, p<0.001) and FMD (r= -0.37, p<0.001).
• Data also showed a significant association of serum heparanase levels with hemoglobin-A1c and body mass index in patients with OSAS.
• In linear regression analysis, serum heparanase and uric acid levels were identified as independent predictors of FMD (R²=0.506, P<0.001; p<0.001 and p=0.001 respectively).