SESSION TITLE: Research Investigations in Obstructive Sleep Apnea SESSION TYPE: Original Investigation Slide PRESENTED ON: Wednesday, October 26, 2016 at 08:45 AM - 10:00 AM PURPOSE: Systemic oxidative stress, as evidenced by increases in urinary creatinine-indexed levels of 8-epi-PGF2a (urinary isoprostanes), has been increasingly implicated in mechanistic models linking moderate to severe sleep disordered breathing (SDB) with prevalent cardiovascular disease. Additionally, modulation of urinary isoprostane levels has also been demonstrated during both initiation and discontinuation of continuous positive airway pressure (CPAP) treatment for moderate to severe SDB. Little is known about the association of urinary isoprostanes with SDB of the severity typically found in a community-based cohort. We report significant associations between both apnea-hyponea index (AHI) and percent sleep time with oxyhemoglobin saturation < 90% (O2LT90) in a cohort of community dwelling adults enrolled in the Sleep Heart Health Study. METHODS: Cross-sectional observational study of 565 Framingham Heart Study participants (mean age 59 years, 55% women) enrolled in the Sleep Heart Health Study, a prospective study of the cardiovascular consequences of SDB. Participants underwent unattended overnight polysomnography for determination of apnea-hypopnea apnea index (AHI) and O2LT90. RESULTS: Multivariable linear regression models were used to evaluate the association of urinary isoprostanes to AHI and O2LT90, adjusting for age, sex, race, current smoking, body mass index, pulmonary function testing, glucose, cholesterol, systolic blood pressure, heart rate and diabetes. Subjects with AHI 5 to <15 (n=149) and those with AHI ≥15 (n=78) had adjusted mean urinary isoprostanes that were 10% (mean ratio 1.095, range 0.979-1.225) and 20% (mean ratio 1.202, range 1.035-1.397) higher, respectively, than those with AHI <5 (n=339, p=0.01). Similarly, those with O2LT90 of 0.25% to 4.0% (n=174) and O2LT90 >4% (n=65) had adjusted urinary isoprostanes that were 8% (mean ratio 1.079, range 0.968-1.204) and 28% (mean ratio 1.277, range 1.089-1.498) higher, respectively, than those with O2LT90 <0.25% (n=327, p <0.01 for test of trend). CONCLUSIONS: Our observations suggest that SDB of a severity common in the community is associated with systemic oxidative stress. However, recent studies examining the association between oxidative stress and SDB have generally excluded this cohort of patients who have less severe, asymptomatic SDB. Given the strong correlation between enhanced oxidative stress and prevalent cardiovascular disease, further study is warranted. CLINICAL IMPLICATIONS: Significant association between urinary isoprostanes and both apnea-hyponea index (AHI) and percent sleep time with oxyhemoglobin saturation < 90% (O2LT90) in a community-based cohort provides further evidence for a strong correlation between obstructive sleep apnea and systemic oxidative stress, and may serve as a marker which has clinical applications for assessing cardiovascular disease risk in the future. DISCLOSURE: The following authors have nothing to disclose: Katherine Green, Terese Hammond, Dan Gottlieb No Product/Research Disclosure Information