Tolerance of transcranial direct current stimulation in psychiatric disorders: An analysis of 2000+ sessions.

Transcranial direct current stimulation (tDCS), a non-invasive, neuromodulatory technique, is being increasingly applied to several psychiatric disorders. In this study, we describe the side-effect profile of repeated tDCS sessions (N = 2005) that were administered to 171 patients (156 adults and 15 adolescents) with different psychiatric disorders [schizophrenia [N = 109], obsessive-compulsive disorder [N = 28], alcohol dependence syndrome [N = 13], mild cognitive impairment [N = 10], depression [N = 6], dementia [N = 2] and other disorders [N = 3]]. tDCS was administered at a constant current strength of 2 mA with additional ramp-up and ramp-down phase of 20 s each at the beginning and end of the session, respectively. Other tDCS protocol parameters were: schizophrenia and obsessive-compulsive disorder: 5-days of twice-daily 20-min sessions with an inter-session interval of 3-h; Mild cognitive impairment/dementia and alcohol dependence syndrome: at least 5-days of once-daily 20-min session; Depression: 10-days of once-daily 30 min session. At the end of each tDCS session, any adverse event observed by the administrator and/or reported by the patient was systematically assessed using a comprehensive questionnaire. The commonly reported adverse events during tDCS included burning sensations (16.2%), skin redness (12.3%), scalp pain (10.1%), itching (6.7%), and tingling (6.3%). Most of the adverse events were noted to be mild, transient and well-tolerated. In summary, our observations suggest that tDCS is a safe mode for therapeutic non-invasive neuromodulation in psychiatric disorders in adults as well as the adolescent population.

Clinical utility and tolerability of transcranial direct current stimulation in mild cognitive impairment.

BACKGROUND: Neuromodulatory interventions like transcranial direct current stimulation (tDCS) is emerging as a potential therapeutic strategy to promote cognitive function in healthy and pathological aging. There is need for more studies evaluating the utility and tolerability of tDCS in Mild cognitive impairment (MCI). Since MCI is considered as the prodromal stage of dementia, it has emerged as the most important target for intervention in dementia. OBJECTIVE AND METHOD: This study investigated the feasibility, tolerability and clinical utility of tDCS in patients with MCI. In this observational study that included 11 patients with MCI, tDCS with an intensity of 2mA and duration of 20minutes per day was administered for 5 consecutive days with anode over left dorsolateral prefrontal cortex (DLPFC) and cathode over right supra orbital region. Treatment outcome was measured using picture memory impairment test (PMIT) immediately and also 1 month after the 5th session of tDCS RESULTS: All the patients tolerated tDCS sessions without any significant adverse effects. Stimulation of left DLPFC with tDCS was noted to significantly improve the immediate and delayed recall performance of the patients in PMIT after five days of stimulation and most of the benefits were persistent at one month follow up. CONCLUSION: This study findings suggests that tDCS is safe and potentially beneficial in combating cognitive deficits in patients with MCI and provides a framework for further studies with better methodology (randomized and sham controlled trial) to investigate the same.