A Relationship between the Obstructive Sleep Apnea Syndrome and the Erythrocyte Sedimentation Rate

The erythrocyte sedimentation rate (ESR) is a marker for inflammation, and it has been identified as a risk factor for atherothrombotic cardiovascular disease. The aim of this study was to determine the relationship between the plasma ESR level and nocturnal oxygen desaturation or other polysomnographic variables and to examine the role of obesity in patients with obstructive sleep apnea syndrome (OSAS).

This retrospective study included 72 patients with a diagnosis of OSAS who underwent overnight polysomnography and routine blood tests between July and December of 2005. We compared the plasma ESR level with the sum of all the polysomnographic variables and divided the patient group into obese and non-obese patients.

The mean ESR level was 8.45 mm/hr. There was a significant difference in the ESR level between genders (P<0.001). A significant correlation was found between the percentage of time spent at a SpO(2) below 90% and the ESR level in the obese group (BMI >/=25, N=43, P=0.012). In addition, the ESR levels had a positive correlation with age in the obese group (P=0.002). However, there was no significant correlation with the percentage of time spent at a SpO(2) below 90% in the whole group of patients and in the non-obese group (BMI <25, N=29). The ESR level showed no correlation with the other polysomnographic variables.

The duration of deoxygenation in obese patients with OSAS may be associated with the ESR level which is an independent predictor of cardiovascular disease.