Page 77 - JCBP-2-3

Journal of Clinical and
Basic Psychosomatics HD-tDCS on pain in SSD-P

States) with a 4 × 1 adaptor. An adult HD cap was used 3. Results
to hold the electrodes in place. The proprietary HD-tDCS
electrodes (1.2 cm external diameter) fitted in the HD 3.1. Sociodemographic and clinical profile
electrode holders supplied with the device were used for Table 1 presents the sociodemographic and clinical profile
the interventions. of the participants in the study, comparing those entering

In the active phase, a 2 mA current was delivered after the active arm first to those entering the sham arm first.
a ramp-up time of 30 seconds. In the sham phase, there The two groups were largely comparable.
was a brief period of stimulation in which the patient Overall, a majority of the participants were female
would have a sensation of current flowing, but no actual (~70%) and had moderate-to-severe somatic symptoms.
current flow would occur. The intervention consisted Comorbid physical conditions were observed in one-
of one session of repeated active or sham HD-tDCS fourth of the patients, with the most common being
administration, followed by a washout period of 1 week. hypertension, followed by diabetes and hypothyroidism.
After this period, the patients entered the sham or active Males and females across the two groups were
phase of the study, respectively. Thus, each patient statistically comparable on baseline sociodemographic
received both active and sham stimulation by the end of
2 weeks.
Table 1. Sociodemographic and baseline clinical profile
2.6. Randomization of Group A (active followed by sham) and Group B (sham
followed by active)
A consecutive sampling technique and simple
randomization were utilized. Eligible patients were Variable Group A Group B P‑value
randomized in a 1:1 allocation ratio by computer- (n=16) (n=14)
assigned random allocation to one of two treatment Age (years) 40.44 (8.93) 39.29 (11.18) 0.75
arms: active or sham HD-tDCS and concealed in Education (years) 11.00 (5.81) 10.64 (7.26) 0.88
sealed envelopes. The random allocation sequence was Gender 0.41
generated by one of the authors, while another author Male 3 (18.7%) 5 (35.7%)
was responsible for enrolling participants and assigning Female 13 (81.3%) 9 (64.3%)
them to the treatment sequence. Patients were blinded to Duration of illness (years) 8.44 (5.27) 8.71 (7.28) 0.90
the treatment sequence. Due to the reduction in sample
size, 16 patients were allocated to the active followed by DSM-5 severity of 0.56
somatic symptoms
the sham treatment arm (Group A), and 14 patients were
allocated to the sham followed by the active treatment Mild to moderate 11 (68.8%) 9 (64.3%)
arm (Group B). Severe 5 (31.2%) 5 (35.7%)
Comorbid physical diagnosis 4 (25.0%) 4 (28.6%) 0.90
2.7. Analysis Comorbid substance 0 (0%) 3 (21.5%) 0.05

Descriptive analysis in terms of frequencies, means, use (alcohol)
and standard deviations, as well as Chi-square tests NRS 7.50 (1.97) 8.42 (1.65) 0.44
for ordinal data and t-tests for normally distributed BPI-H (average pain) 7.00 (1.75) 7.71 (2.02) 0.87
data, was employed. Repeated measures analysis of BPI-H (interference) 6.10 (2.22) 7.09 (1.63) 0.34
variance (ANOVA) was employed to test the hypothesis GAD-7 12.12 (6.30) 12.71 (4.97) 0.64
regarding the effect of HD-tDCS on the pain scores,
with treatment order (active-sham versus sham-active), PHQ- 9 13.12 (6.37) 14.28 (4.76) 0.23
treatment condition (active versus sham), and time SSS- 8 17.56 (8.79) 17.14 (8.06) 0.44
(baseline, immediately after stimulation, and at follow- PDI-7 38.31 41.35 (18.78) 0.23
ups) as the independent variables. Analysis of covariance (11.92)
(ANCOVA) was applied to test the interaction of MMSE 29.62 (0.81) 29.85 (0.53) 0.63
order and treatment group. ANCOVA test was chosen CGI-S 4.06 (0.77) 4.07 (0.83) 0.45
as it has been considered to increase the statistical Notes: Results are expressed in frequency (%) or mean (SD); Significant
power of crossover studies, as in this case. ANCOVA level was set at P<0.05.
improves precision and avoids bias in the widest set of Abbreviations: BPI-H: Brief Pain Inventory-Hindi version: CGI-S:
circumstances. In addition, our scores were measured Clinical Global Impression-Severity: GAD-7: Generalized Anxiety
27
Disorder 7 Scale: MMSE: Mini-Mental State Assessment; NRS:
across three-time points. Statistical analysis was Numerical Rating Scale; PDI-7: Pain Disability Index 7; PHQ-9: Patient
conducted using SPSS software version 21. Health Questionnaire 9; SSS-8: Somatic Symptom Scale-8.

Volume 2 Issue 3 (2024) 4 doi: 10.36922/jcbp.2002