["Addiction, Volume 121, Issue 8, Page 2116-2126, August 2026. ", "\nAbstract\n\nBackground and aims\nSleep disruptions increase the risk of substance misuse. Substance use—especially stimulants—can increase acute and chronic sleep dysfunction. This study aimed to estimate the associations between sleep disturbance and stimulant use over time among participants with stimulant use disorder (StUD).\n\n\nDesign\nIn this secondary analysis, a Random Intercept Cross‐Lagged Panel Model (RI‐CLPM) was used to assess sleep disturbance and stimulant use over 8 weeks among participants with StUD.\n\n\nSetting\nUnited States of America.\n\n\nParticipants\nThe analysis included 793 participants with StUD enrolled across 3 randomized controlled trials in the National Institute on Drug Abuse's Clinical Trials Network (CTN): CTN‐0037, CTN‐0048 and CTN‐0068.\n\n\nMeasurements\nSelf‐reported sleep disturbance was harmonized as a binary indicator across trial measures at each week. Stimulant use days per week were captured by Timeline Follow Back. Baseline covariates included age, sex, race/ethnicity, employment status, presence of depressive symptoms, any psychiatric history, treatment arm and trial.\n\n\nFindings\nSleep disturbance was associated with a higher average number of stimulant use days the following week [β = 0.15, 95% confidence interval (CI) = 0.09, 0.22, P < 0.001], and greater stimulant use was linked to increased odds of subsequent sleep disturbance (odds ratio = 1.20, 95% CI = 1.14, 1.26, P < 0.001).\n\n\nConclusions\nHigher‐than‐usual stimulant use appears to be associated with increased likelihood of sleep disturbance the following week, and vice versa.\n\n"]