Clinical presentation and risk factors for severe outcomes in suspected kush poisoning, Sierra Leone, June–November 2025

Introduction: Sierra Leone declared a national public health emergency in April 2024 in response to widespread use of kush, an illicit substance containing nitazene-class synthetic opioids and synthetic cannabinoids. We describe clinical presentation and identify risk factors for severe outcomes among patients presenting with suspected acute kush poisoning. Methods: Guided by the Risk Environment Framework, we conducted a multicentre retrospective cohort study at four treatment centres in Sierra Leone (June–November 2025). Cases included patients with acute opioid toxidrome and reported kush use within 24 hours. Severe outcomes were defined hierarchically as death, mechanical ventilation, or clinical instability (GCS <8 or qSOFA ≥2). Mixed-effects logistic regression identified independent risk factors for severe outcomes. Results: Among 312 patients, the median age was 24 years (IQR 19–31); 94% were male, and 45 (14%) had experienced severe outcomes, including 9 deaths (3%). Clinical findings reflected opioid toxidrome: altered consciousness (75%), miosis (63%), and respiratory depression (41%). Independent risk factors for severe outcomes included polysubstance use (adjusted odds ratio [aOR] 2.4; 95% CI 1.2–4.6), previous overdose (aOR 2.3; 95% CI 1.2–4.5), delayed presentation >6 hours (aOR 2.0; 95% CI 1.0–3.9), and wound infection (aOR 2.1; 95% CI 1.1–4.2). Among naloxone recipients, 77% responded; 27% required repeat dosing. Conclusion: Kush poisoning presents with opioid toxidrome consistent with nitazene pharmacology. Polysubstance use, prior overdose, delayed presentation, and wound infection are identifiable and modifiable risk factors for severity. Findings support targeted naloxone distribution, community-based harm reduction interventions, and integrated treatment services.