(1) Background: Attention deficit hyperactivity disorder (ADHD) is a common comorbid condition in opioid use disorder (OUD) and is associated with a more severe course of substance use. Patients with severe OUD who have not responded to oral opioid maintenance treatment can be treated with intravenous diamorphine up to three times per day. Here, we investigated the prevalence of ADHD among patients undergoing either daily diamorphine maintenance treatment or daily oral opioid maintenance treatment. (2) Methods: We assessed all participants with the WURS-k and the ADHD-SR. The Diagnostic Interview for ADHD in Adults (DIVA) was performed with all participants who met the cut-off in the WURS-k and/or ADHD-SR. (3) Results: The overall prevalence of ADHD was 17.9%. Prevalence of ADHD among patients undergoing daily diamorphine maintenance treatment was 14.3%. Prevalence of ADHD among patients undergoing daily oral opioid maintenance treatment was 20.3%. The combined presentation of ADHD was the most prevalent condition. In urine samples of participants with comorbid ADHD, heroin was detected the most and cocaine the least frequently. (4) Conclusions: Almost one out of five patients with OUD suffered from comorbid ADHD. In 83.3%, ADHD had not been diagnosed prior to participation in this study. Thus, patients with SUD could benefit from being routinely screened for ADHD.

Acute stress triggers rapid physiological adaptations, yet how distinct stress modalities shape the human circulating molecular landscape remains unclear. We performed longitudinal deep plasma proteomics and targeted metabolomics across three paradigms: psychological stress, controlled physical stress, and combined psychological–physical stress induced by bungee jumping. Despite robust hypothalamic–pituitary–adrenal axis activation, psychological stress induced minimal plasma proteomic and metabolic changes, whereas physical stress triggered rapid, coordinated proteome remodeling accompanied by stressor-specific metabolic adaptations. Combined stress elicited the strongest and most persistent proteomic response, defining a graded molecular signature across stress modalities. Cross-paradigm integration identified a stress-associated protein core enriched for immune granule effectors, RNA-binding proteins, and vesicle-linked signatures, suggesting regulated extracellular release. Consistently, extracellular vesicle profiling in the mixed-stress paradigm supported vesicle-associated secretion, while functional experiments indicated that glucocorticoid signaling alone is insufficient to trigger release. Together, these findings reveal stressor identity as a key determinant of the human circulating molecular response.