Evaluating the relationship between marijuana use, aggressive behaviors, and victimization: an epidemiological study in colombian adolescents

Introduction

Adolescence is a critical period of human development characterized by biological, psychological, and social transitions. During this stage, maturation of the brain’s reward and emotional regulation systems makes adolescents especially sensitive to external influences, including the availability and use of psychoactive substances [1], 2]. Among these substances, marijuana stands out as one of the most frequently used illicit drugs worldwide [3]. Its prevalence, combined with evolving public discourse and changing policies in many regions, has heightened interest in understanding its potential impact on youth well-being.

A central concern regarding marijuana consumption is its interplay with aggression and victimization [4]. Conceptually, aggression encompasses behaviors intended to harm others, ranging from verbal harassment to physical violence, whereas victimization refers to being the target of such harmful behaviors [5]. Both outcomes are linked to disrupted developmental trajectories, impaired mental health, and compromised academic and social functioning [6]. However, the direction and magnitude of marijuana’s role in these aggressive and victimizing behaviors remain a subject of debate [7]. On one hand, cultural narratives and some empirical evidence suggest that marijuana’s calming, sedative, and euphoric effects might reduce hostility and aggressive impulses [8], 9]. On the other hand, studies suggest that marijuana may impair emotional regulation, increase irritability, and worsen impulse control, thereby increasing the likelihood of aggressive behavior or vulnerability to victimization, particularly in risky or marginal social contexts [10], [11], [12].

The mixed empirical findings underscore the complexity of interpreting marijuana’s role in adolescent aggression and victimization. Several theoretical frameworks can be used to explain its role. From an emotional regulation perspective, marijuana use might interact with underlying mood dysregulation, making some adolescents more prone to lose control or become entangled in conflict [13]. Social Network theories suggest that adolescents who use marijuana may be embedded in peer networks that normalize risk-taking and aggression, potentially increasing both perpetration and victimization [14]. Stress-coping models posit that adolescents might turn to substances such as marijuana in response to environmental stressors, inadvertently placing themselves in high-risk situations for aggression or victimization [15].

A key methodological challenge in this literature is the tendency to treat adolescent marijuana users as a homogeneous group. However, adolescent substance use behaviors are diverse. Many youths who consume marijuana also use other drugs, including alcohol, tobacco, or inhalants [16], each carrying its own well-documented risks [17], 18]. This polydrug context can obscure marijuana’s unique effects, as aggression or victimization may be influenced by the additive or interactive effects of multiple substances. Moreover, the sequence of drug initiation may matter [19], 20]. Initiating marijuana use before other substances could set a different developmental trajectory compared to starting with other drugs first and then introducing marijuana. By failing to differentiate exclusive marijuana users from those who use multiple substances, and by not accounting for the timing of different drug initiations, previous studies risk cofounding marijuana’s potential impact with that of other substances.

The present study seeks to address this complexity by employing a multigroup analytical approach that classifies adolescents into distinct categories based on their marijuana and other drug use histories. We identify exclusive marijuana users and compare them to adolescents who report no drug use, those who use only one other drug, and those who use multiple drugs. Within the marijuana-using groups, we further distinguish between adolescents who started with marijuana before using any other substance and those who began with other drugs prior to marijuana use. By parsing these different user profiles, we aim to isolate marijuana’s specific contributions to aggression and victimization, separate from the confounding effects of other drugs.

This approach allows us to test longstanding theoretical propositions such as marijuana’s role in aggression and victimization. If marijuana use alone is linked to certain forms of aggression or victimization, this finding would support models emphasizing the drug’s pharmacological effects on emotional and behavioral regulation. Alternatively, if polydrug use groups demonstrate the strongest associations with aggression and victimization, it would highlight the importance of broader social-ecological factors and the synergistic effects of multiple substances. Evidence of differential effects based on the sequence of drug initiation could suggest a developmental ordering that shapes later behavioral outcomes, offering insights into prevention and early intervention strategies.

In sum, this study extends the debate on marijuana’s role in adolescent aggression and victimization by using a multigroup design. By moving beyond simplistic comparisons of marijuana users vs. non-users, we aim to clarify how exclusive vs. polydrug patterns, and the temporal sequencing of marijuana use, inform our understanding of the relationship between marijuana use and aggression and victimization.

Methods

Results

Regression models

Table 4 presents the odds ratios indicating the change in the odds of reporting aggressive behavior for individuals in the marijuana use group, while controlling for other variables in the models. The parameters estimated for the controls are presented in the supplemental materials.

Table 4:

Odds ratios for reporting aggression/victimization across marijuana use groups compared to no-drug use, controlling for other variables.

	Group aggression		Individual aggression		Victimization		Harassment among classmates
	AOR2	95 % CI2	AOR2	95 % CI2	AOR2	95 % CI2	AOR2	95 % CI2
No-drug use
vs. Exclusive	1.74**	1.17, 2.52	2.14***	1.44, 3.10	1.47*	1.04, 2.04	1.25	0.92, 1.70
vs. Initial	2.54***	2.03, 3.16	2.97***	2.36, 3.72	1.61***	1.31, 1.98	1.95***	1.60, 2.37
vs. Subsequent	1.78**	1.24, 2.54	1.36	0.92, 1.98	1.44*	1.02, 2.02	1.73**	1.21, 2.44
One drug
vs. Exclusive	0.59**	0.39, 0.85	0.71	0.48, 1.03	0.67*	0.47, 0.93	0.43***	0.31, 0.58
vs. Initial	0.92	0.73, 1.14	1.07	0.85, 1.33	0.78*	0.63, 0.96	0.69***	0.56, 0.84
vs. Subsequent	0.97	0.86, 1.08	0.91	0.80, 1.02	0.88*	0.79, 0.98	0.84**	0.76, 0.94
Multiple
vs. Exclusive	0.99	0.66, 1.42	1.35	0.90, 1.94	0.96	0.68, 1.33	0.61**	0.45, 0.83
vs. Initial	1.50***	1.21, 1.87	1.95***	1.55, 2.43	1.1	0.90, 1.35	0.97	0.79, 1.17
vs. Subsequent	1.27	0.99, 1.62	1.17	0.89, 1.52	1.12	0.88, 1.41	0.97	0.76, 1.23

1. *p < 0.05; **p < 0.01; ***p < 0.001. Fixed effect. sex, age, gender, retention, father education and mother education.

Group aggression

Compared with students in the NON-DRUG, those categorized within the EXCLUSIVE had 1.74 times higher odds of reporting group aggression, as indicated by AOR=1.74 (95 % Confidence Interval [CI]: 1.17 to 2.52, p <0.05). Similarly, the odds of reporting aggression were greater for the INITIAL, with an AOR=2.54 (95 % CI: 2.03 to 3.16, p <0.001), and for the SUBSEQUENT, with an AOR of 1.78 (95 % CI: 1.24 to 2.54, p <0.05). When compared to ONE-DRUG, students in the EXCLUSIVE group presented a lower likelihood of engaging in group aggression, with an AOR=0.59 (95 % CI: 0.39 to 0.85, p <0.001), and no differences were observed when compared to the INITIAL and SUBSEQUENT groups. Lastly, compared to MULTIPLE-DRUG group, participants in the INITIAL group showed significantly increased odds of reporting group aggression, with an AOR of 1.50 (95 % CI: 1.21 to 1.87, p <0.001) and not differences were observed in the EXCLUSIVE and SUBSEQUENT group.

Individual aggression

Compared with students in the NON-DRUG, those in the EXCLUSIVE group were significantly more likely to report individual aggression, AOR=2.14 (95 % CI: 1.44 to 3.10, p <0.001)., Those in the INITIAL group also were more likely to report individual aggression, AOR=2.97 (95 % CI: 2.36 to 3.72, p <0.001). However, the SUBSEQUENT group did not show a significant increase in the odds of individual aggression (AOR=1.36, 95 % CI: 0.92 to 1.98, p >0.05). Compared to ONE-DRUG group, no significant difference in the odds of individual aggression was observed. Finally, compared to MULTIPLE-DRUG, the INITIAL group indicated significantly higher odds of reporting individual aggression (AOR=1.95, 95 % CI: 1.55 to 2.43, p <0.001).

Harassment among classmates

Compared with students in the NON-DRUG group, we found significant increase in odds for INITIAL AOR=1.95 (95 % CI: 1.60 to 2.37, p <0.001) and SUBSEQUENT groups AOR=1.73 (95 % CI: 1.21 to 2.44, p <0.01), indicating a higher report of harassment in these groups. Compared with students in the ONE-DRUG, students in the EXCLUSIVE group had lower odds of reporting harassment AOR=0.43 (95 % CI: 0.31 to 0.58, p <0.001). Similarly, we observed lower odds for INITIAL AOR=0.69 (95 % CI: 0.56 to 0.84, p <0.001) and SUBSEQUENT AOR=0.84 (95 % CI: 0.76 to 0.94, p <0.01). Finally, compared to MULTIPLE-DRUG, EXCLUSIVE group showed significantly lower odds of reporting harassment (AOR=0.61, 95 % CI: 0.45 to 0.83, p <0.01), while no significant differences were found for either INITIAL or SUBSEQUENT.

Victimization

Compared with students in the NON-DRUG group, students in the EXCLUSIVE group had an increased odds of experiencing victimization, AOR=1.47 (95 % CI: 1.04 to 2.04, p <0.05). Similar increases were observed for INITIAL (AOR=1.61, 95 % CI: 1.31 to 1.98, p <0.001) and SUBSEQUENT groups AOR=1.44 (95 % CI: 1.02 to 2.02, p <0.05). When compared to students in the ONE-DRUG, students in the EXCLUSIVE AOR=0.67 (95 % CI: 0.47 to 0.93, p <0.05), INITIAL AOR=0.78 (95 % CI: 0.63 to 0.96, p <0.05), and SUBSEQUENT AOR=0.88 (95 % CI: 0.79 to 0.98, p <0.05) exhibited lower odds of victimization. No significant differences in the odds of victimization were observed when comparing with students in the MULTIPLE-DRUG.

Figure 1 provides a graphical representation of the comparisons among groups and outcomes, presenting the coefficients that represent the differences between marijuana use and non-use groups. Points on the graph indicates the estimates and lines 95 % confidence intervals produced by the regression models.

Figure 1:

Aggression and victimization among marijuana use and non-use groups.

Discussion

Overall, the data suggest that as substance use becomes more extensive, shifting from no drug use to single or multiple-drug use, rates of aggressive behavior and victimization increase. Adolescents with no history of drug use reported the lowest levels of harassment, group aggression, individual aggression, and victimization. In contrast, those engaging in multiple-drug use consistently exhibited the highest prevalence of these problematic behaviors, illustrating that polydrug involvement may relate to conditions more conducive to aggression and vulnerability.

Our results demonstrate that even when marijuana is used exclusively, adolescents face an increased likelihood of aggression and victimization relative to their non-using peers. These findings challenge narratives that position marijuana use as primarily benign and emphasize the need to consider its potential role in heightening aggression-related risks, even in the absence of other substances. At the same time, the comparison across different groups of marijuana users reveals that adolescents who used marijuana exclusively generally showed lower odds of aggression and victimization compared to those who started with marijuana and then moved on to other drugs (INITIAL) or those who began with other drugs before introducing marijuana (SUBSEQUENT). This pattern suggests that the sequence of drug initiation and the complexity of an adolescent’s substance use profile may shape the association between marijuana use and aggressive behavior. For instance, INITIAL and SUBSEQUENT groups may be more deeply embedded in risk-prone social networks or may have other underlying risk factors that magnify the likelihood of aggression and victimization.

Another notable finding is that, in several comparisons, marijuana-using groups exhibited lower odds of reporting aggressive behaviors and victimization compared to adolescents who reported using other substances. This indicates that marijuana’s influence should not be considered in isolation; instead, it must be understood within the broader context of an adolescent’s drug use repertoire. Polydrug use, especially involving multiple substances, appears to be more strongly and consistently associated with heightened aggression and victimization than marijuana use alone.

Taken together, these findings highlight the importance of moving beyond dichotomous categorizations of “marijuana user” and “non-user.” Future research should incorporate additional contextual and environmental factors, such as frequency of use, social settings, and the presence of co-occurring mental health conditions, to better elucidate the mechanisms underlying these relationships. Furthermore, interventions aimed at reducing aggression among substance-using adolescents may benefit from a more targeted approach, distinguishing between different substance use patterns and considering the temporal order of drug initiation. This perspective can help tailor prevention and treatment programs to the distinct profiles of adolescents’ substance use behaviors, ultimately contributing to more effective strategies for reducing aggression and victimization in this population.

Our findings contribute to the ongoing debate on the relationship between marijuana use and aggressive behavior among adolescents, yet we acknowledge that the social and environmental contexts in which these behaviors occur are equally important considerations. For instance, students attending private schools or residing in more privileged neighborhoods may have fewer opportunities to encounter insecure environments and, as a result, potentially less exposure to both aggressive behaviors and drug use. Conversely, less privileged neighborhoods may heighten vulnerability to environmental stressors that can foster aggression, regardless of substance use patterns.

In this study, while we controlled for certain demographic variables (e.g., parental education level, grade repetition, and age), we did not include school type (public vs. private) or other detailed measures of socioeconomic status (SES) beyond parental education. Nor did we incorporate neighborhood characteristics, as these data were not available in the dataset. Thus, we cannot fully disentangle the effects of marijuana use from those of the broader environmental contexts that adolescents inhabit. Future research should consider incorporating a wider range of social determinants. These might include neighborhood-level indicators of economic disadvantage, community violence exposure, and school quality, as well as more refined measures of family-level SES. While these issues extend beyond the scope of our current analysis, we encourage future investigations to integrate comprehensive social and environmental measures to more fully capture the interplay between drug use, socioeconomic context, victimization and aggressive behaviors.

The worldwide conversation regarding the legalization of marijuana has been gaining importance over the decade as an increasing number of countries including United States are introducing laws for both recreational use of the substance. As regulations progress and evolve in this area there are differing opinions surrounding how marijuana may influence behaviors such, as aggression. Colombia, the origin of our data, finds itself in a discussion due to its long-standing struggles with drug trafficking and violence issues that have plagued the nation with several social problems. The efforts to combat drug related problems have typically centered around substances like cocaine; nonetheless marijuana has also played a role in Colombia’s drug landscape in terms of both production and consumption patterns. At present a bill advocating for the legalization of marijuana for adults is progressing through Congress. This proposal has raised apprehensions regarding its effects, on the populace. It highlights the significance of studying how marijuana affects behaviors such, as aggression and victimization.