“…Relative to healthy controls (8.8%), significantly more individuals with OUD (80.6%) have ratings ≥5 on the Pittsburgh Sleep Quality Index, indicative of poor sleep quality (Hartwell, Pfeifer, McCauley, Moran-Santa Maria, & Back, 2014), which has also been verified objectively through polysomnography (PSG) testing (Kay, Eisenstein, & Jasinski, 1969; Kay, 1975; Xiao et al, 2010). Sleep disturbance is evident among patients who are newly enrolled into OMT (Burke et al, 2008; Nordmann et al, 2016), as well as long-term OMT patients (Stein et al, 2004). Longitudinal evaluations suggest sleep does not naturally improve over the course of methadone treatment (Nordmann et al, 2016; Peles, Schreiber, Hamburger, & Adelson, 2011) and that sleep may in fact worsen, with the development of central sleep apnea in some patients (Wang et al, 2005).…”