Modeling the risks and benefits of depression treatment for children and young adults

Acceptability, safety and tolerability of antidepressant repetitive transcranial magnetic stimulation for adolescents: A mixed-methods investigation

OBJECTIVE

Major depressive disorder (MDD) is relatively common in adolescence, with far-reaching impacts. Current treatments frequently fail to alleviate depression severity for a substantial portion of adolescents. Repetitive transcranial magnetic stimulation (rTMS) may assist with this unmet clinical need. However, little is known about adverse events (AEs) experienced by adolescents receiving rTMS, subjective treatment experiences of adolescents and their parents, or treatment acceptability.

METHODS

Fourteen adolescents (16.5 years ± 1.2; 71.4% female) with MDD received 20 sessions of either high-frequency (10 Hz; n = 7) left dorsolateral prefrontal cortex (DLPFC) or low-frequency (1 Hz; n = 7) right DLPFC rTMS. AEs were monitored at baseline and at weekly intervals via New York State Psychiatric Institute Side Effects Form for Children and Adolescents. Eight adolescents and nine parents participated in interviews regarding subjective treatment experience, analysed via content analysis.

RESULTS

Drowsiness and lethargy were common AEs, reported by 92.3% of participants in week one. Number of AEs decreased throughout treatment course (after 5 treatments: M = 11.23, SD = 5.00; after 20 treatments: M = 8.92, SD = 5.95). Thirty-five AEs emerged during treatment, most commonly transient dizziness. Frequency, severity, and number of AEs reported were equivalent between treatment groups. Treatment adherence and satisfaction were high. Qualitative findings identified three themes relating to rTMS experience: Preparation and connection; Physical experience of treatment; and Perceived role of treatment.

LIMITATIONS

Sample size was small, therefore findings are preliminary.

CONCLUSIONS

rTMS was an acceptable treatment for adolescent MDD, from both adolescents' and parents' perspectives, and was safe and well-tolerated, as AE frequency and type did not differ from rTMS treatment courses in adults.

Modeling smoking-attributable mortality among adults with major depression in the United States

Tobacco-related health disparities disproportionately affect smokers with major depression (MD). Although tobacco simulation models have been applied to general populations, to date they have not considered populations with a comorbid mental health condition. We developed and calibrated a simulation model of smoking and MD comorbidity for the US adult population using the 2005-2018 National Surveys on Drug Use and Health. We use this model to evaluate trends in smoking prevalence, smoking-attributable mortality and life-years lost among adults with MD, and changes in smoking prevalence by mental health status from 2018 to 2060. The model integrates known interaction effects between smoking initiation and cessation, and MD onset and recurrence. We show that from 2018 to 2060, smoking prevalence will continue declining among those with current MD. In the absence of intervention, people with MD will be increasingly disproportionately affected by smoking compared to the general population; our model shows that the smoking prevalence ratio between those with current MD and those without a history of MD increases from 1.54 to 2.42 for men and from 1.81 to 2.73 for women during this time period. From 2018 to 2060, approximately 484,000 smoking-attributable deaths will occur among adults with current MD, leading to 11.3 million life-years lost. Ambitious tobacco control efforts could alter this trajectory. With aggressive public health efforts, up to 264,000 of those premature deaths could be avoided, translating into 7.5 million life years gained. This model can compare the relative health gains across different intervention strategies for smokers with MD.

Breaking Away: The Role of Homeostatic Drive in Perpetuating Depression

We propose that the complexity of regulatory interactions modulating brain neurochemistry and behavior is such that multiple stable responses may be supported, and that some of these alternate regulatory programs may play a role in perpetuating persistent psychological dysfunction. To explore this, we constructed a model network representing major neurotransmission and behavioral mechanisms reported in literature as discrete logic circuits. Connectivity and information flow through this biobehavioral circuitry supported two distinct and stable regulatory programs. One such program perpetuated a depressive state with a characteristic neurochemical signature including low serotonin. Further analysis suggested that small irregularities in glutamate levels may render this pathology more directly accessible. Computer simulations mimicking selective serotonin reuptake inhibitor (SSRI) therapy in the presence of everyday stressors predicted recidivism rates similar to those reported clinically and highlighted the potentially significant benefit of concurrent behavioral stress management therapy.

Increasing Resilience to Traumatic Stress: Understanding the Protective Role of Well-Being

The brain maintains homeostasis in part through a network of feedback and feed-forward mechanisms, where neurochemicals and immune markers act as mediators. Using a previously constructed model of biobehavioral feedback, we found that in addition to healthy equilibrium another stable regulatory program supported chronic depression and anxiety. Exploring mechanisms that might underlie the contributions of subjective well-being to improved therapeutic outcomes in depression, we iteratively screened 288 candidate feedback patterns linking well-being to molecular signaling networks for those that maintained the original homeostatic regimes. Simulating stressful trigger events on each candidate network while maintaining high levels of subjective well-being isolated a specific feedback network where well-being was promoted by dopamine and acetylcholine, and itself promoted norepinephrine while inhibiting cortisol expression. This biobehavioral feedback mechanism was especially effective in reproducing well-being's clinically documented ability to promote resilience and protect against onset of depression and anxiety.