Efficacité et tolérance de la stimulation magnétique transcrânienne (SMTr) dans le traitement des dépressions chez le sujet âgé : revue de la littérature

Efficacy and Tolerability of Repetitive Transcranial Magnetic Stimulation on Suicidal Ideation: A Systemic Review and Meta-Analysis

OBJECTIVE

This study aimed to investigate the efficacy of repetitive transcranial magnetic stimulation (rTMS) in treating suicidal ideation in patients with mental illness.

METHOD

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Major electronic databases were systematically searched from the time of their inception until July 22, 2021. The primary outcome was the mean change in the scores for suicidal ideation. The secondary outcome was the mean change in depression severity.

RESULTS

Ten randomized controlled trials were eligible with 415 participants in the active treatment group (mean age = 53.78 years; mean proportion of women = 54.5%) and 387 participants in the control group (mean age = 55.52 years; mean proportion of women = 51.78%). rTMS significantly reduced suicidal ideation (k = 10, n = 802, Hedges' g = -0.390, 95% confidence interval [CI] = -0.193 to -0.588, p <.001) and severity of depressive symptoms (k = 9, n = 761, Hedges' g = -0.698, 95% CI = -1.023 to -0.372, p < 0.001) in patients with major mental disorders. In the subgroup analysis, rTMS reduced suicidal ideation among patients with non-treatment-resistant depression (non-TRD) (-0.208) but not in those with TRD. rTMS as combination therapy had a larger effect than did monotherapy (-0.500 vs. -0.210). Suicidal ideation significantly reduced in patients receiving more than ten treatment sessions (-0.255). Importantly, the rTMS group showed favorable tolerability without major adverse events.

CONCLUSION

The study showed that rTMS was effective and well-tolerated in reducing suicidal ideation and depression severity in patients with major mental disorders.

Evaluation and Treatment of Vascular Cognitive Impairment by Transcranial Magnetic Stimulation

The exact relationship between cognitive functioning, cortical excitability, and synaptic plasticity in dementia is not completely understood. Vascular cognitive impairment (VCI) is deemed to be the most common cognitive disorder in the elderly since it encompasses any degree of vascular-based cognitive decline. In different cognitive disorders, including VCI, transcranial magnetic stimulation (TMS) can be exploited as a noninvasive tool able to evaluate in vivo the cortical excitability, the propension to undergo neural plastic phenomena, and the underlying transmission pathways. Overall, TMS in VCI revealed enhanced cortical excitability and synaptic plasticity that seem to correlate with the disease process and progression. In some patients, such plasticity may be considered as an adaptive response to disease progression, thus allowing the preservation of motor programming and execution. Recent findings also point out the possibility to employ TMS to predict cognitive deterioration in the so-called "brains at risk" for dementia, which may be those patients who benefit more of disease-modifying drugs and rehabilitative or neuromodulatory approaches, such as those based on repetitive TMS (rTMS). Finally, TMS can be exploited to select the responders to specific drugs in the attempt to maximize the response and to restore maladaptive plasticity. While no single TMS index owns enough specificity, a panel of TMS-derived measures can support VCI diagnosis and identify early markers of progression into dementia. This work reviews all TMS and rTMS studies on VCI. The aim is to evaluate how cortical excitability, plasticity, and connectivity interact in the pathophysiology of the impairment and to provide a translational perspective towards novel treatments of these patients. Current pitfalls and limitations of both studies and techniques are also discussed, together with possible solutions and future research agenda.

Evaluation and Treatment of Vascular Cognitive Impairment by Transcranial Magnetic Stimulation

The exact relationship between cognitive functioning, cortical excitability, and synaptic plasticity in dementia is not completely understood. Vascular cognitive impairment (VCI) is deemed to be the most common cognitive disorder in the elderly since it encompasses any degree of vascular-based cognitive decline. In different cognitive disorders, including VCI, transcranial magnetic stimulation (TMS) can be exploited as a noninvasive tool able to evaluate in vivo the cortical excitability, the propension to undergo neural plastic phenomena, and the underlying transmission pathways. Overall, TMS in VCI revealed enhanced cortical excitability and synaptic plasticity that seem to correlate with the disease process and progression. In some patients, such plasticity may be considered as an adaptive response to disease progression, thus allowing the preservation of motor programming and execution. Recent findings also point out the possibility to employ TMS to predict cognitive deterioration in the so-called "brains at risk" for dementia, which may be those patients who benefit more of disease-modifying drugs and rehabilitative or neuromodulatory approaches, such as those based on repetitive TMS (rTMS). Finally, TMS can be exploited to select the responders to specific drugs in the attempt to maximize the response and to restore maladaptive plasticity. While no single TMS index owns enough specificity, a panel of TMS-derived measures can support VCI diagnosis and identify early markers of progression into dementia. This work reviews all TMS and rTMS studies on VCI. The aim is to evaluate how cortical excitability, plasticity, and connectivity interact in the pathophysiology of the impairment and to provide a translational perspective towards novel treatments of these patients. Current pitfalls and limitations of both studies and techniques are also discussed, together with possible solutions and future research agenda.

[Transcranial direct current stimulation (tDCS) for depression: Results of nearly a decade of clinical research]

OBJECTIVE

Since 2006 transcranial direct current stimulation (tDCS) has been investigated in the treatment of depression. In this review, we discuss the implications and clinical perspectives that tDCS may have as a therapeutic tool in depression from the results reported in this domain.

METHODS

A comprehensive literature review has found nearly thirty articles - all in English - on this topic, corresponding to clinical studies, placebo-controlled or not, case reports and reviews.

RESULTS

Several meta-analyses showed that the antidepressant effects of active tDCS are significant against placebo, but variable, mainly due to the heterogeneity of the patients included in the studies, for example regarding the resistance to antidepressant treatment.

CONCLUSIONS

Specific recommendations for the use of tDCS in treating depression may not yet be available, but some elements of good practice can be highlighted. Of particular note is that anodal tDCS of the left prefrontal cortex at 2mA for 20 minutes per day has a potential therapeutic value without risk of significant side effects: tDCS offers safe conditions for clinical use in the treatment of depression.

[Negative hallucination, self-onsciousness and ageing]

BACKGROUND

Negative hallucinations are characterized by a defect in perception of an object or a person, or a denial of the existence of their perception. Negative hallucinations create blank spaces, due to both an impossible representation and an incapability of investment in reality. They have a close relationship with Cotard's syndrome, delusional theme of organ denial observed in melancholic syndromes in the elderly.

METHODS

Phenomenological approach. The phenomenology of negative hallucinations provides quite an amount of information on the origin of the psychotic symptoms when one is rather old.

RESULTS

The connections between hallucinations, mood disorders and negative symptoms are often difficult to live with for the nearest and dearest. Negative hallucinations require a strict approach to identify their expression that is crucial because a wide heterogeneity exists within the pathological pictures, as in Cotard's syndrome. Although the negative hallucination has an anti traumatic function in elderly people fighting against mental pain, it still represents a deficiency in symbolization. The prevalence of this symptom is without doubt underestimated, although its presence often underlines thymic suffering that is more striking. These hallucinatory symptoms have an important impact on the patients' daily life, and they appear to be prisoners of a suffering, which cannot be revealed.

CONCLUSIONS

We propose in this article to review the clinical symptoms of negative hallucinations in the elderly and the way to manage them. The medicinal approaches are not always effective. A greater place must be given to what is in connection with the body, aiming at a strong impact and thus to offer non-pharmacological approaches, such as somatic ones, which can be either invasive (electroconvulsive therapy) or not (transcranial magnetic stimulation).

The role of electroconvulsive and neuromodulation therapies in the treatment of geriatric depression

Geriatric depression is associated with increased mortality because of suicide and decreases in functional and physical health. Many elders' depression is resistant to psychotherapy and medication and can become chronic. Electroconvulsive therapy (ECT) is increasingly used in the treatment of medication-resistant or life-threatening geriatric depression. Neuromodulation therapies (subconvulsive, focal, or subconvulsive and focal) are alternatives for the management of treatment-resistant depression in the elderly. Therapies that combine both strategies could be safer but may not be as effective as ECT. This review covers the evidence on the safety and efficacy of ECT and the neuromodulation therapies in geriatric depression.

rTMS for pharmacoresistant major depression in the clinical setting of a psychiatric hospital: effectiveness and effects of age

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive method of brain stimulation used in the treatment of drug-resistant major depressive disorder (MDD). It has been suggested that the efficacy of rTMS decreases with the age of the patient, but the data are contradictory. Here, we analyze in our clinical setting the efficacy of a 3-week rTMS treatment in drug-resistant MDD during a 3 month period and the potential influence of age on this efficacy.

METHODS

Stimulation consisted of 15 sessions of rTMS over the dorsolateral prefrontal cortex. Clinical evaluations included the Hamilton Depression Rating Scale (HDRS), and the Beck Depression Inventory (BDI) at baseline, after 3 weeks of treatment, and 1 month and 3 months after the last session.

RESULTS

Data from 93 patients issued from the 178 patients active file were analyzed. The antidepressant effect observed in the two age groups (<65 and ≥65) did not differ at the end of the treatment and 3 months later, with a comparable number of responders (50% decrease in HDRS score from baseline) (53.3% for age <65 versus 46.7% for age ≥65, p=0.51). The treatment had a significant effect over time. We found no evidence of the age affecting outcome at 3 months after the last session.

LIMITATIONS

Previous antidepressant treatments, and therapeutic drug use modifications after rTMS treatment, degree of pharmaco-resistance or duration of current episode are not reported.

CONCLUSION

RTMS of the DFPLC is effective as an add-on treatment for cases of pharmacologically refractory major depression, independent of the patient age.

The prefrontal cortex influence over subcortical and limbic regions governs antidepressant response by N=H/(M+R)

We review the evidence for relationships between metabolic activity of cortical, subcortical and limbic brain regions in depression and the efficacy of antidepressant agents. The influence of these regions can be described by an algebraic equation, N=H/(M+R), where N represents a homeostatic level of executive function, H represents prefrontal (Brodmann areas 9, 10, 11, 12; 46) and cingulate cortex activity (24, 25; 32), M represents subcortical (hippocampus, parahippocampal gyrus) influences, and R represents limbic (amygdala) influences. This hypothesis is based on depressed prefrontal cortex and enhanced amygdala and hippocampal metabolism in major depressive disorder, and the remission of these changes by most antidepressant interventions. The therapeutic efficacy of antidepressant strategies may depend less on their presumptive molecular mechanisms of action and more on their ability to restore the predominant metabolic and executive functions of the prefrontal cortex, and dampen excessive subcortical and limbic influences.