RT Journal Article SR Electronic T1 31 The association of delta power during sleep with concurrent nocturnal and next-day pain: results from a cohort of female participants with temporomandibular joint pain JF BMJ Open Respiratory Research JO BMJ Open Resp Res FD British Thoracic Society SP A16 OP A16 DO 10.1136/bmjresp-2021-bssconf.28 VO 8 IS Suppl 1 A1 Reid, Matthew A1 Abishek, Dave A1 Mun, Chung A1 Rojo-Wissar, Darlynn A1 Phillips, Jane A1 Buenaver, Luis A1 Campbell, Claudia A1 Haythornthwaite, Jennifer Jennifer A1 Finan, Patrick A1 Smith, Michael YR 2021 UL http://bmjopenrespres.bmj.com/content/8/Suppl_1/A16.1.abstract AB Introduction Existing data demonstrate reduced delta power during sleep in chronic pain and depressed patients. However, there has been little examination of the relationship between delta power and next-day reports of pain. We tested the extent to which nocturnal (during the concurrent sleep period) and daytime pain reports are associated with delta power during sleep, as well as the extent to which this association is moderated by depressive symptoms. We hypothesised that reduced delta power and SWS would be associated with increased pain, pain catastrophising, and pain sensitivity.Methods 149 female participants with insomnia and temporomandibular joint pain (TMD) were recruited. We examined nocturnal and daytime measures of pain (pain severity, average pain), pain catastrophizing, and objective pain sensitivity (obtained through quantitative sensory testing (QST)), and calculated relative nocturnal delta (0.5-3.4 Hz) power using polysomnography. We fit linear regression models correcting for depressive symptom severity, age, and total sleep time, and further examined the moderating effect of depression severity on these measures.Results reduced delta power was associated with increased average nocturnal pain (Unstandardized β = -17.67, p= 0.02), morning pain (Unstandardized β = -15.67, p=0.02), and average next-day pain (Unstandardized β = -16.74, p= 0.03). Depression severity did not moderate these relationships. Delta power was not significantly associated with objective pain-sensitivity, nocturnal, or daytime pain catastrophising. However the association between nocturnal pain catastrophising and delta power was moderated by depressive symptom severity (p = 0.04). Simple slopes analysis revealed that when participants had low depressive symptoms (<13 CESD), increased delta power significantly predicted reduced nocturnal pain catastrophising.Discussion These findings demonstrate that delta power during sleep is associated with both nocturnal and daytime experience of pain in patients with TMD. In patients with TMD and low depressive symptoms, reduced delta power was associated with increased nocturnal pain catastrophising.