Neurostimulation Methods in the Treatment of Depression: A Comparison of rTMS, tDCS, and Venlafaxine Using a Pooled Analysis of Two Studies

The Economics of Treatment for Depression

The global prevalence of depression has risen over the past three decades across all socioeconomic groups and geographic regions, with a particularly rapid increase in prevalence among adolescents (aged 12-17 years) in the United States. Depression imposes large health, economic, and societal costs, including reduced life span and quality of life, medical costs, and reduced educational attainment and workplace productivity. A wide range of treatment modalities for depression are available, but socioeconomic disparities in treatment access are driven by treatment costs, lack of culturally tailored options, stigma, and provider shortages, among other barriers. This review highlights the need for comparative research to better understand treatments' relative efficacy, cost-effectiveness, scalability, and potential heterogeneity in efficacy across socioeconomic groups and country and cultural contexts. To address the growing burden of depression, mental health policy could consider reducing restrictions on the supply of providers, implementing digital interventions, reducing stigma, and promoting healthy lifestyles.

Treatment of behavioral and psychological symptoms of dementia using transcranial magnetic stimulation: a systematic review

OBJECTIVE

Behavioral and psychological symptoms of dementia (BPSD) are a group of noncognitive symptoms that occur commonly among individuals with dementia. These symptoms worsen the morbidity and mortality among individuals with dementia and significantly increase the cost of caring for these individuals. Transcranial magnetic stimulation (TMS) has been shown to have some benefits in the treatment of BPSD. This review provides an updated summary of the effect of TMS on BPSD.

METHODS

We conducted a systematic review of PubMed, Cochrane, and Ovid databases on the use of TMS to treat BPSD.

RESULTS

We found 11 randomized controlled studies that evaluated the use of TMS among individuals with BPSD. Three of these studies examined the effect of TMS on apathy, two of which showed significant benefit. Seven studies showed that TMS significantly improves BPSD: six using repetitive transcranial magnetic stimulation (rTMS) and one using transcranial direct current stimulation (tDCS). Four studies, two evaluating tDCS, one evaluating rTMS, and one evaluating intermittent theta-burst stimulation (iTBS) showed a nonsignificant impact of TMS on BPSD. Adverse events were predominantly mild and transitory in all studies.

CONCLUSION

Available data from this review indicate that rTMS is beneficial for individuals with BPSD, especially among individuals with apathy, and is well tolerated. However, more data are needed to prove the efficacy of tDCS and iTBS. Additionally, more randomized controlled trials with longer treatment follow-up and standardized use of BPSD assessments are needed to determine the best dose, duration, and modality for effective treatment of BPSD.

Recent advances in understanding depressive disorder: Possible relevance to brain stimulation therapies

Recent research has provided novel insights into the major depressive disorder (MDD) and identified certain biomarkers of this disease. There are four main mechanisms playing a key role in the related pathophysiology, namely (1) monoamine systems dysfunction, (2) stress response, (3) neuroinflammation, and (4) neurotrophic factors alteration. Robust evidence on the decreased homovanillic acid in the cerebrospinal fluid (CSF) of patients with MDD supports a rationale for therapeutic stimulation of the medial forebrain bundle activating the dopamine reward system. Both activation and suppression of the hypothalamic-pituitary-adrenal (HPA) axis in MDD and related conditions indicate usefulness of its evaluation for the disease subtyping. Elevated proinflammatory cytokines (specifically, interleukin-6) in CSF imply the role of neuroinflammation resulting in activation of the tryptophan-kynurenine pathway. Finally, neuroplasticity and trophic effects of the brain-derived neurotrophic factor (BDNF) may be related to both structural abnormalities of the brain in MDD and the underlying mechanisms of various therapies. In addition, the gut-brain interaction is pivotal, since lack of beneficial microbes confer the risk of MDD through negative effects on the dopamine system, HPA axis, and vagal nerve. All these factors may be highly relevant to treatment of MDD with contemporary brain stimulation therapies.