Long-term follow-up study of medicinal cannabis in post-traumatic stress disorder: focus on aggressiveness, impulsivity, and suicidality

Introduction

Post-traumatic stress disorder (PTSD) is a chronic and often disabling psychiatric condition characterized by persistent symptoms of re-experiencing, avoidance, negative alterations in cognition and mood, and hyperarousal. In many patients, PTSD is also associated with behavioral dysregulation, including aggressiveness, impulsivity, and suicidality, which significantly contribute to morbidity and functional impairment. Despite the availability of pharmacological and psychotherapeutic interventions, a substantial proportion of patients remain only partially responsive to conventional treatment. In recent years, medicinal cannabis (MC) has been increasingly utilized as an adjunctive therapeutic option, particularly in patients with comorbid pain and sleep disturbances. However, data regarding its long-term impact on behavioral outcomes in PTSD remain limited.

Methods

This longitudinal, naturalistic follow-up study included 390 adult patients diagnosed with PTSD who were licensed to receive MC treatment through the Ministry of Health. The cohort comprised patients with “pure” PTSD, PTSD with comorbid depressive disorders, and PTSD associated with chronic pain.

Clinical assessments were conducted using the Clinician-Administered PTSD Scale (CAPS), Quality of Life Scale (QOLS), and Clinical Global Impression–Improvement (CGI-I). Behavioral parameters were evaluated using the Modified Overt Aggression Scale (MOAS), Plutchik Impulsivity Scale (IS), and Suicidal Ideation Attributes Scale (SIDAS).

Patients were followed longitudinally with periodic clinical evaluations for up to ten years in most cases. MC treatment was provided by licensed suppliers and consisted predominantly of THC-enriched formulations (up to 26%) of different strains, administered via inhalation, oils/extracts, or sprays. Daily dosing ranged from 1.5 to 2.5 grams and was adjusted individually according to clinical response and tolerability.

Results

At baseline, the majority of patients were receiving conventional pharmacotherapy, including antidepressants, mood-stabilizers, and analgesics, and some were cannabis-naïve.

Over the course of follow-up, MC treatment was associated with:

• Improvement in quality of life (up to 50% increase in QOLS scores)
• Clinical improvement as reflected in CGI-I ratings (up to 60%)
• Reduction in behavioral dysregulation, including aggressiveness, impulsivity, and suicidal ideation (MOAS, IS, SIDAS scores).

A proportion of patients reported reductions or discontinuations of concomitant medications, particularly analgesics and sedative agents. The most consistent improvements were observed among patients with comorbid depression and/or chronic pain. No serious adverse events or clinically significant exacerbations were reported during the follow-up period. During the longitudinal observation, several patients discontinued MC use or changed to a clinical setting for various administrative, logistical, or clinical reasons.

Conclusions

This long-term naturalistic study provides observational evidence suggesting that medicinal cannabis, when used within a structured clinical framework, may be associated with improvements in quality of life and reductions in behavioral dysregulation in patients with PTSD. The findings are consistent with previous short- and medium-term observations and support the potential role of MC as an adjunctive treatment in selected patient populations, particularly those with comorbid conditions.

However, given the observational design, variability in cannabis strans and formulations, and absence of a control group, these results should be interpreted with caution. Further well-designed, controlled studies are required to better define the efficacy, safety, and optimal treatment parameters of medicinal cannabis in PTSD, particularly with respect to long-term behavioral outcomes.

References

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