Abstract Rationale The increasing use of electronic nicotine delivery systems (ENDS) among adolescents has become a public health challenge worldwide. While vaping is often perceived as less harmful than conventional smoking, evidence suggests strong links to mental health problems and poor sleep. Dual use of ENDS and conventional cigarettes may have a cumulative effect on neurobehavioral and psychosocial outcomes, particularly in low- and middle-income settings where prevention policies remain limited. Methods A cross-sectional, population-based study was conducted in 12 public schools in Valledupar, Colombia, in 2024. The sample included 9,069 adolescents aged 10-18 years (mean 13.9 ± 1.9; 49.8% female). Data were collected through a standardized survey including demographic variables, vaping habits, sleep characteristics, and the Goldberg Anxiety and Depression Scale. Dual tobacco use was defined as concurrent consumption of electronic and conventional cigarettes. Poisson regression models were used to estimate adjusted prevalence ratios (aPR) for depression, anxiety, and insufficient sleep, controlling for age, sex, school, and nighttime device use (‘vamping’). Results Dual users showed the highest adjusted risk across all outcomes:• Depression: aPR = 1.30 (95% CI: 1.23-1.38; p .001)• Anxiety: aPR = 1.48 (95% CI: 1.35-1.63; p .001)• Insufficient sleep: aPR = 1.28 (95% CI: 1.06-1.44; p = .007)In comparison, single users of electronic or conventional cigarettes showed lower but still significant associations with mental health symptoms. No significant interaction was found between ENDS use alone and sleep duration, but the dual consumption pattern revealed a consistent cumulative burden of emotional and behavioral disturbances.. Conclusions Dual users—adolescents consuming both electronic and conventional tobacco—exhibited the greatest risk for depressive and anxiety symptoms, as well as sleep disturbances, suggesting a synergistic neurobehavioral toxicity from multiple nicotine exposure routes. These findings underscore the need for school-based mental health screening, integrated prevention programs, and stronger regulatory measures addressing the marketing and availability of ENDS to youth. Funding: This study was self-funded as part of a master’s thesis in epidemiology at Fundación Universitaria del Área Andina, Valledupar, Colombia. Ethics: Approved by the NeumoCenter Research Ethics Committee, Valledupar, Colombia. This abstract is funded by: None
Orozco et al. (Fri,) studied this question.