TY - JOUR T1 - Effect of periodic limb movements on plasma nitric oxide levels in patients with obstructive sleep apnoea JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.sleepandbreathing-2017.P87 VL - 3 IS - suppl 1 SP - P87 AU - Snigdha Pusalavidyasagar AU - Reena Kartha AU - Adnan Abbasi Y1 - 2017/04/01 UR - http://openres.ersjournals.com/content/3/suppl_1/P87.abstract N2 - Introduction Periodic limb movements (PLMs) have been associated with cardiovascular disease (CVD). PLMs cause sympathetic activation, which impacts vascular tone and endothelial function leading to the development of CVD. Nitric oxide (NO) plays a key role in the regulation of vascular tone and disturbances in NO levels have been implicated in development of CVD. This study was designed to measure changes in NO levels in OSA patients with excessive PLMs, with a long-term goal of gaining insights into CVD.Methods 25 patients with no prior diagnosis of OSA, naïve to CPAP, ages 25-75 years, BMI > 30 kg/m2 were recruited. All patients underwent PSG. 17 patients had OSA, based on the Apnea-hypopnea index. Subjects were divided into group 1 with PLMI<20 per hour and group 2 with PLMI > 20 per hour. Venous blood was collected from all subjects pre- and post- diagnostic PSG. NO levels were assayed.Results There were 12 patients in group 1 (mean PLMI of 1.5±2.8) and 5 patients in group 2 (mean PLMI 46.2±18.5). Group 1 had more severe OSA compared to group 2 (mean AHI 62.4±40.9 vs. 21.9±10.5), p-value 0.049. Results were analyzed with paired-samples t-test. Mean NO level in all patients pre PSG was 30.0±14.4 and post PSG was 26.5±14.2 (p=0.04). In group 1, mean NO levels, pre and post PSG were 24.3±7.1 and 20.9±7.6 (p=0.016). In group 2, mean NO levels pre and post PSG were 43.7±19 and 39.9±18.1 (p=0.49).Conclusions OSA likely contributes to reduction in NO levels, but this effect is not evident in OSA patients with excessive PLMs, suggesting different CVD mechanisms. ER -