Modulation of self-appraisal of illness, medication adherence, life quality and autonomic functioning by transcranial direct current stimulation in schizophrenia patients.

OBJECTIVES

Little is known about the impact of fronto-temporal transcranial direct current stimulation (tDCS) on attitudes toward mental illness, psychosocial and autonomic functioning, life quality, and medication adherence among schizophrenia patients.

METHODS

Sixty schizophrenia patients were randomly allocated to receive 10 sessions of active (2 mA, 20 min, 2 sessions/day for five weekdays) or sham fronto-temporal tDCS. Self-Appraisal of Illness Questionnaire (SAIQ), Medication Adherence Rating Scale (MARS), World Health Organization Quality of Life-BREF (WHOQOL-BREF) and indices of heart rate variability (HRV) were measured at baseline, immediately after tDCS and at one-month follow-up visit.

RESULTS

There were significant group-by-time interactions for scores of SAIQ presence/outcome subscale, total MARS and its subscale of subjective response to taking medication, WHOQOL-BREF psychological domain. Relative to sham, tDCS significantly improved self-awareness of presence/outcome of schizophrenia (Cohen's d = 0.465, p = 0.0011), subjective response to taking medication (Cohen's d = 0.639, p < 0.001) and psychological domain of life quality (Cohen's d = 0.459, p = 0.00114). These effects lasted for less than one month. The group-by-time interactions were non-significant for clinician-rated psychosocial functioning, mean RR intervals, and all HRV indices.

CONCLUSION

Fronto-temporal tDCS briefly optimizes self-reported insight levels, beliefs about treatment adherence, and psychological domain of life quality in patients with schizophrenia. Further studies are required to confirm whether patients treated with 5-day, 10-session tDCS in combination with multisession "maintenance" stimulation every month would attain favourable outcomes.

SIGNIFICANCE: We provide novel evidence for the potential utility of tDCS in schizophrenia.