Burden, Risk Factors, and Knowledge of Non-fatal Opioid Overdose Among Injectable Drug Users: A Cross-sectional Study.

Abstract

Background: Opioid overdose is a significant public health problem among injectable drug users (IDUs), with non-fatal overdoses being a strong predictor of fatal overdoses. This study aimed to evaluate the burden, risk factors, and awareness related to non-fatal overdose among IDUs in Kolkata, India.

Methods: This cross-sectional study was conducted from September 2023 to March 2025 at two opioid substitution therapy centers and two government hospitals in Kolkata. A total of 331 IDUs diagnosed with opioid use disorders participated. Data were collected through face-to-face interviews using a structured questionnaire assessing socio-demographics, substance use, overdose risk factors, and knowledge of overdose management. Descriptive statistics and regression analysis were employed.

Results: A total of 331 IDUs were included. Among them, 73% used heroin, and 72.3% used buprenorphine. Major risk factors were sudden increases in heroin dosage (88.1%), injecting alone (83.8%), and sharing syringes (82.5%). Additionally, 24.1% reported a history of incarceration. Only 55.5% knew about calling an ambulance during an overdose, while 96.3% were aware that higher doses increase overdose risk. None were aware of naloxone use. Most participants (77.4%) expressed the need for more training on overdose management, while 88.7% feared aggression from overdose victims when administering naloxone. Attitude showed a protective trend, while knowledge and cumulative risk scores were not significantly associated with overdose in regression analysis.

Conclusion: The findings underscore the need for comprehensive overdose prevention programs, including naloxone distribution and training and community-based education to address knowledge gaps and reduce opioid overdose mortality among IDUs in Kolkata.