BackgroundWithdrawal from cannabis use is associated with sleep disturbances, often leading to resumption of use. Less is known about the impact of abstinence on sleep in adolescence, a developmental window associated with high rates of sleep disturbance. This study investigated effects of sustained abstinence on self-reported sleep quality and disturbance in adolescents reporting frequent cannabis use. MethodsNon-treatment seeking adolescents, recruited from school screening surveys and the community, with frequent cannabis use (MAge=17.8, SDAge=1.7, 47% female, 45% non-white) were randomized to four weeks of biochemically-verified abstinence, motivated via contingency management (CB-Abst, n=53), or monitoring without an abstinence requirement (CB-Mon, n=63). A mixed-effects model was used to predict change in Pittsburgh Sleep Quality Index (PSQI) scores. ResultsParticipants in CB-Abst reported higher overall PSQI scores than those in CB-Mon (M=1.06, p=0.01) indicating worse sleep during the four-week trial. Sleep disruptions in CB-Abst increased during Week 1 of abstinence (d=0.34, p=0.04), decreased during Week 2 (d=0.36, p=0.04), and remained constant for the rest of the trial. At Week 4, sleep was comparable to baseline levels for those in CB-Abst (p=0.87). Withdrawal-associated sleep disruption in the CB-Abst group was circumscribed to increases in sleep latency (b=0.35; p=0.05). ConclusionsCannabis abstinence in adolescents was associated with transient delayed onset of sleep initiation falling asleep during the first week of abstinence. Findings highlight withdrawal-associated changes in sleep latency as an intervention target for supporting adolescents attempting abstinence. Future research should use objective measures of sleep and focus on elucidating mechanisms underlying sleep disturbances with cannabis use and withdrawal.