Evaluating the use of electroconvulsive therapy in low-middle income countries: A narrative review

BACKGROUND

Electroconvulsive therapy (ECT) is a well-accepted intervention for treatment-resistant, serious mental illnesses. Its acceptability, efficacy, and tolerability are well documented in high-income settings, but less so in lower- and middle-income countries (LMICs). This report is a narrative review of ECT practice in the latter setting.

METHODS

A literature search was conducted using Medline and PubMed. Initial results yielded 81 publications in English. Following the screening, 19 papers were included to evaluate the information on ECT practice and perceptions.

RESULTS

Reports from LMICs on efficacy, tolerability, and perceptions of ECT were relatively sparse. In general, they confirm its use mostly for treatment-resistant major mental illnesses (i.e., depression, schizophrenia, bipolar disorder). Both modified and unmodified forms of ECT are used and considered equally effective, although the former is better tolerated. Use of unmodified ECT remains significant in LMICs due to its low cost and limited resource requirements. In general, there is satisfaction with ECT and its outcomes. The education of patients and families, content process, and research have been noted as areas to improve.

CONCLUSIONS

ECT is perceived as an effective intervention in LMICs, but use of unmodified ECT remains controversial. There is a need for the development and use of global guidelines to improve clinician training, knowledge sharing with patients and their families, and outcome research.

Differentiating transcranial magnetic stimulation cortical and auditory responses via single pulse and paired pulse protocols: A TMS-EEG study

OBJECTIVE

We measured the neurophysiological responses of both active and sham transcranial magnetic stimulation (TMS) for both single pulse (SP) and paired pulse (PP; long interval cortical inhibition (LICI)) paradigms using TMS-EEG (electroencephalography).

METHODS

Nineteen healthy subjects received active and sham (coil 90° tilted and touching the scalp) SP and PP TMS over the left dorsolateral prefrontal cortex (DLPFC). We measured excitability through SP TMS and inhibition (i.e., cortical inhibition (CI)) through PP TMS.

RESULTS

Cortical excitability indexed by area under the curve (AUC_(25-275ms)) was significantly higher in the active compared to sham stimulation (F(1,18) = 43.737, p < 0.001, η² = 0.708). Moreover, the amplitude of N100-P200 complex was significantly larger (F(1,18) = 9.118, p < 0.01, η² = 0.336) with active stimulation (10.38 ± 9.576 µV) compared to sham (4.295 ± 2.323 µV). Significant interaction effects were also observed between active and sham stimulation for both the SP and PP (i.e., LICI) cortical responses. Finally, only active stimulation (CI = 0.64 ± 0.23, p < 0.001) resulted in significant cortical inhibition.

CONCLUSION

The significant differences between active and sham stimulation in both excitatory and inhibitory neurophysiological responses showed that active stimulation elicits responses from the cortex that are different from the non-specific effects of sham stimulation.

SIGNIFICANCE

Our study reaffirms that TMS-EEG represents an effective tool to evaluate cortical neurophysiology with high fidelity.

Evidence for prefrontal cortex hypofunctioning in schizophrenia through somatosensory evoked potentials

Patients with schizophrenia (SCZ) exhibit a variety of symptoms related to altered processing of somatosensory information. Little is known, however, about the neural substrates underlying somatosensory impairments in SCZ. This study endeavored to evaluate somatosensory processing in patients with SCZ compared to healthy individuals by generating somatosensory evoked potentials through stimulation of the right median nerve. The median nerve was stimulated by a peripheral nerve stimulator in 34 SCZ and 33 healthy control (HC) participants. The peripheral nerve stimulus (PNS) intensity was adjusted to 300 percent of sensory threshold and delivered at 0.1 Hz. The EEG data were acquired through 64-channels per 10-20 montage. We collected and averaged 100 trials and the recording electrodes of interest were the F3/F5 electrodes representing the dorsolateral prefrontal cortex (DLPFC) and C3/CP3 representing the somatosensory cortex (S1). In response to PNS, SCZ participants experienced over the DLPFC N30 amplitude that was significantly smaller than that of HC participants. By contrast, S1 N20 was of similar amplitude between the two groups. In addition, we found an association between N20 and N30 amplitudes in SCZ but not in HC participants. Our findings suggest that patients with SCZ demonstrate aberrant processing of somatosensory activation by the DLPFC locally and not due to a connectivity disruption between S1 and DLPFC. These results could help to develop a model through which to DLPFC hypofunctioning could be studied. Our findings may also help to identify a potential biological target to treat somatosensory information processing related deficits in SCZ.