Assessment of the quality of life following transcranial direct current stimulation in patients with diabetic peripheral neuropathy

Abstract

Background: Diabetic peripheral neuropathy (DPN) is an impairment of nerve activities in the course of the frame and might disturb autonomic, sensory, and motor functions that affect the patient's well-being. The foremost principle of the study was to examine the influence of transcranial direct current stimulation (tDCS) on the quality of life (QoL) in DPN. Methods: Twenty patients of both sexes suffering from DPN participated in the study. The tDCS was used for 20 min, 3 sessions per week for 2 months. Quality of life was assessed using the Neuro-Qol questionnaire before and after the study program. Results: There was a significant influence of tDCS on QoL in patients with DPN. Conclusion: The study findings suggested that tDCS is effective in improving the overall quality of life in patients with DPN as it has a significant effect in reducing neuropathic pain. Consequently, tDCS reduces anxiety and fatigue and improves upper and lower limb functions with a direct effect on applied cognition, general concern, and depression.

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© 2020 Journal of Advanced Pharmacy Education & Research | Published by SPER Publication 9
Assessment of the quality of life following transcranial direct
current stimulation in patients with diabetic peripheral
neuropathy
Shereen H. ElSayed1,2, Samah AlSaid Moawd2, 3, Walid Kamal Abdelbasset3,4*
1Rehabilitation Sciences Department, Faculty of Health and Rehabilitation Sciences, Princess Nourah bintAbdulrahman University, Riyadh, Saudi Arabia. 2Department of
Physical Therapy for Cardiovascular/Respiratory Disorders and Geriatrics, Faculty of Physical Therapy, Cairo University, Giza, Egypt.3Department of Physical Therapy and
Health Rehabilitation, College of Applied Medical Sciences, Prince Sattam Bin Abdulaziz University, Alkharj, Saudi Arabia.4Department of Physical Therapy, Kasr Al-Aini
Hospital, Cairo University, Giza.
Correspondence:
Dr. Walid Kamal Abdelbasset, Department of Physical Therapy and Health Rehabilitation, College of Applied Medical Sciences, Prince Sattam Bin
Abdulaziz University, Alkharj, Saudi Arabia.E-mail: walidkamal.wr @ gmail.com, Mobile: +966561014872.
ABSTRACT
Background: Diabetic peripheral neuropathy (DPN) is an impairment of nerve activities in the course of the frame and might disturb
autonomic, sensory, and motor functions that affect the patient’s well-being. The foremost principle of the study was to examine the
influence of transcranial direct current stimulation (tDCS) on the quality of life (QoL) in DPN. Methods: Twenty patients of both sexes
suffering from DPN participated in the study. The tDCS was used for 20 min, 3 sessions per week for 2 months. Quality of life was
assessed using the Neuro-Qol questionnaire before and after the study program. Results: There was a significant influence of tDCS on
QoL in patients with DPN. Conclusion: The study findings suggested that tDCS is effective in improving the overall quality of life in
patients with DPN as it has a significant effect in reducing neuropathic pain. Consequently, tDCS reduces anxiety and fatigue and
improves upper and lower limb functions with a direct effect on applied cognition, general concern, and depression.
Keywords:transcranial direct current stimulation, diabetic peripheral neuropathy, Neuro-Qol
Introduction
The origin of pain in diabetic peripheral neuropathy (DPN) is
not fully understood. Disturbances in the peripheral or central
nervous system can be associated with hyperglycemia because
this is the main metabolic abnormality of diabetes.[1]
DPN is an imbalance in the daily activity of the nerves at some
areas of the body and may impair the functions of self-
movement mobility. The proposed rate of DPN levels is from
16% to an excessive rate such as 66%. In a step with a look at
the benefit of fitness and nutrients nationwide Tan et al., studies
the cost of treatment of diabetic foot and found early
intervention and conservative treatment will reduce the burden
of DF.[2] Neuropathic ache as “ache springing up as a right away
result of lesions or ailment influencing the somatosensory
gadget.[3] Continual neural ache reduces the quality of life,
disrupts sleep, and reduces endeavor. Moreover, it extensively
affects emotional health and lack of treatment compliance.[4]
The ache of diabetic neuropathy is troublesome to cause
scientific problems. It is frequently related to temper and
disturbed sleepiness and patients with diabetic neuropathy look
for medicinal treatments more than people with different styles
of diabetes.[5] Patients may also have decreasing of physical
activities and movability, increasing of muscle fatigability, and
poor consequences in their community life. Providing of
substantial pain relief may improve lifestyle practices such as
sleeping and liveliness.[6]
While starting treatment, a real purpose would be to achieve
around 50% lowering of pain severity. The secondary purpose
is to recover or improve functional parameters, sleep quality,
psychological status, and quality of life (QoL). Although it was
prospected that pain relief could be achieved by development in
capabilities, there is a preferred consent that desirable control
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E-ISSN: 2249-3379
How to cite this article: Shereen H. ElSayed, Samah AlSaid Moawd, Walid
Kamal Abdelbasset. Assessment of the quality of life following transcranial
direct current stimulation in patients with Diabetic Peripheral Neuropathy. J
Adv Pharm Edu Res 2020;10(1):9-13.
Source of Support: Nil, Conflict of Interest: None declared.
Original Article

Shereen H. ElSayed et al.:Assessment of the quality of life following transcranial direct current stimulation
10 Journal of Advanced Pharmacy Education & Research | Jan-Mar 2020 | Vol 10 | Issue 1
of blood glucose should be the first step in the management of
the DPN.[7]
In tDCS, a vulnerable non-invasive and painless direct current
stimulates the cerebral cortex. It has some advantages that can
lead to long-remaining modulation for cortical characteristics,
and also it is easy to be administered and performed.[8]
The tDCS mechanism of action confirmed that it causes
polarity-based shifts of the resting membrane potential of
neurons beneath the electrodes, thereby converting neural
excitation at the site of stimulation and related regions. The
anode usually stimulates greater neuronal activities this is why
it also includes placed at the target area such as number one
motor area (m1), vertix (c3 or c4), or frontal (f 3 or f4)
regions.[9)
Materials and Methods
Subjects
Twenty patients from both sex with diabetic painful neuropathy
participated in this study with the age range of 50-60 years old
with the mean age of 52.8 ± 1.88 years and BMI range of
34.41-37.22 with mean 36.73±2.49 kg/m². About the sex
distribution, there were 12 (60%) females and 8 (40%) males.
All patients were provided with a written informed consent
before participating in the study.
Inclusion criteria
• Each patient suffers from diabetes since >5 years ago.
• A mild to moderate pain according to visual analogue
scale (VAS (
• The patients’ age ranged from 50 to 60 years.
Exclusion criteria
• Subjects with an unstable medical or psychiatric
disorder.
• Subjects with any device implanted for controlling
pain such as deep or vagal brain stimulators.
• Hospitalized subjects.
• Pain not attributed to other causes such as spinal cord
injury.
Instrumentations
For assessment of the quality of life, the neuropathic
quality of lifestyles (neuro-QoL) was used. Neuro-QoL
questionnaire includes short forms that contains group of
items, which have been carefully selected from item banks to
facilitate the estimation of each affected person's health.[10]
To assess pain, the neuropathy pain scale (NPS)was adjusted
to assess the quality of pain associated with neuropathy. The
NPS consists of 10 items.
Treatment procedures
Transcranial direct current stimulator
(tDCS)
Gymna Uniphy device (Phyaction 787) was used in the
treatment procedures. It is an advanced electrotherapy device
that can produce wide range of electric current from low- to
medium-frequency currents passing through one or two output
channels, with or without the use of the built-in vacuum unit.
Procedures of application of tDCS:
• The anode electrode has been placed above the
primary motor cortex (m1) while cathode has been
placed above the supra-orbital area. The DC was
commenced with an increase in a ramp-like mode for
many seconds up to achieving 1 mA (0.04 mA/cm2
current density).
• The session has been stopped if the subject felt
headache, severe itching sensation or severe
numbness under the electrode areas, dizziness, or
experience of vomiting.
Statistical analysis
Data analysis was carried out using SPSS software version 19
(SPSS, Chicago, Illinois, USA). A paired t-test was used to
compare between pre- and post-study measures (mean values of
neuropathic pain and QoL scores) within each group. The
statistical significance was set at p<0.05.
Results
The purpose of the study was to assess the influence of
transcranial direct current stimulation (TDCS) on QoL in
diabetic peripheral neuropathy. Data obtained from patient
groups regarding the neuropathic quality of life (Neuro-QoL)
and neuropathy pain scale (NPS) were statistically analyzed and
compared before initiation and after completing the treatment
program.
Table 1. Comparison between pre and post-treatment mean values of the neuropathy pain scale
Pre-
( ±SD)
Post-
( ±SD)
MD
% of change
t- value
p-value
Sig
Sharp
7.6 ± 0.75
3.75 ± 2.24
3.85
50.65
9.34
0.0001
S
Hot
7.9 ± 0.85
3.15 ± 0.93
4.75
60.12
21.97
0.0001
S
Dull
7.85 ± 0.93
3.15 ± 1.34
4.7
59.87
15.22
0.0001
S
Cold
7.9 ± 0.96
3.15 ± 0.74
4.75
60.12
16.43
0.0001
S
Pain
7.75 ± 0.71
3.6 ± 1.46
4.15
53.54
13.02
0.0001
S
Sensitive pain
8.15 ± 0.93
2.05 ± 0.99
6.1
74.84
21.78
0.0001
S
Itchy pain
8 ± 0.97
2.15 ± 1.22
5.85
73.12
16.03
0.0001
S
Unpleasant pain
8.05 ± 0.88
2.4 ± 1.42
5.65
70.18
17.29
0.0001
S
Deep pain
7.95 ± 0.75
2.45 ± 1.31
5.5
69.18
14.72
0.0001
S
Surface pain
8.4 ± 0.82
2.25 ± 1.2
6.15
73.21
17.57
0.0001
S

: Mean; SD: Standard deviation; MD: Mean difference; t-value: Paired t-value; p-value: Probability value; S: Significant

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Shereen H. ElSayed et al.:Assessment of the quality of life following transcranial direct current stimulation
Journal of Advanced Pharmacy Education & Research | Jan-Mar 2020 | Vol 10 | Issue 1 11
Table 2. Comparison between pre and post treatment mean values of Neuro- QoL questionnaire
Pre-
( ±SD)
Post-
( ±SD)
MD
% of change
t- value
p-value
Sig
Sigma
1.7 ± 0.73
1.35 ± 0.48
0.35
20.58
3.19
0.005
S
Applied condition
2.05 ± 0.88
4.5 ± 0.6
-2.45
119.51
-10.97
0.0001
S
Depression
4.1 ± 0.64
1.45 ± 0.82
2.65
64.63
12.69
0.0001
S
General concern
2.3 ± 0.73
3.95 ± 0.75
-1.65
71.73
-11
0.0001
S
Anxiety
3.5 ± 0.6
1.9 ± 0.64
1.6
45.71
9.49
0.0001
S
Fatigue
3.55 ± 0.82
1.9 ± 0.64
1.65
46.47
7.9
0.0001
S
Lower limb function
2 ± 0.56
3.9 ± 0.71
-1.9
95
-9.97
0.0001
S
Upper limb function
3.75 ± 0.78
4.75 ± 0.44
-1
26.66
-4.87
0.0001
S

: Mean; SD: Standard deviation; MD: Mean difference; t-value: Paired t-value; p-value: Probability value; S: Significant
Discussion
The current study showed a significant decrease in tactile pain
score, with a change of 74% compared to pre-treatment and
this is in accordance with the study performed by Marlow et al.,
2013 who provided that HF rTMS (High frequency
repearedtranscranial magnetic stimulation), as well as anodal
tDCS stimulation of m1 (M1-tDCS) provided parallel ache
upgrades compared to the FDA-approved drugs for
fibromyalgia.[11]
For persistent primary pain due to traumatic spinal cord injury,
five daily periods of tDCS (motor cortex for 20min) reduced
50% of pain level in 6 of 11 individuals conducting prescribed
therapy. Moreover, Zaghi et al. advocated a significant increase
of 20-30% with 10 times per day among patients with
fibromyalgia conducting DLPFC or motor cortex
stimulation.[12]
Although the facts about the using of tDCS for ache relief are
limited and great clinical trials are needed to be performed, the
results of studies carried out with the aid of previous which
displayed that the anodes of tDCS were applied over the motor
cortex in patients with continual ache can set off substantial
ache comfort, in comparison to the baseline level previous to
the tDCS.[13-15]
The present study found out extensive lower in itchy pain rating
put up intervention compared to pre treatment that comes in
accordance with randomized clinical trials emphasized that
stimulation of the cortex outstandingly decreases ache related to
several chronic conditions, which appear in patients with
fibromyalgia.[16-18]
In number of studies, showed the persistence of the effect post
stimulation, with trials exhibiting ache enhancements remaining
for 4-month after stimulations. Similar protocols executed by
Knotkova et al yielded sizeable pain relief in sufferers with
continual neuropathic pain of numerous etiologies.[19] The
effects of this technique showed a great growth in implemented
cognition score put up treatment than before treatment that
approved by Kuo and Nitsche who reported useful
consequences on the motor and cognitive capabilities.[20]
Outcomes of our study also go along with prior study which
stated that the using of tDCS for one session with 1 mA for
seventeen minutes or eighteen sessions with 2 mA for thirty
minutes resulted in varied cognition improvement of the
participants.[21] These outcomes pass on with Iuculano and
Cohen, Cohen et al, and Snowball et al that reported cognitive
improvements after 6 months of stimulation with tDCS, and
may linger beyond then.[22-24]
Within the contemporary observe the massive improvement
that arises in depression because of pain comfort and the direct
impact of tDCS on melancholy this trust research that displayed
that tDCS may invert the unhealthy changes and return to the
ideal condition within the widespread psychological patients.[25]
This agree with Brunoni et al [26] who concluded that tDCS may
accelerate the anti-depression effects, especialy if associated
with various treatments .and agree with Knotkova et al [27] who
found that tDCS may fasten the therapeutic effects more than
other anti-depressors that takes prolonged time for the healing
stage. Moreover, tDCS is considered as a desirable treatment
for despair, mainly for people who cannot tolerate the negative
impacts of antidepressants.
The end result of this study come in contrast to, Loo et al
evaluated tDCS in the double-blind randomized study which
included 40 outpatients with despair, treatment has changed
into furnished for treatment for 5 sessions, three days weekly,
anodal stimulation was supplied to the left dorsolateral
prefrontal cortex (DLPFC) at 1 mA for 20 minutes, melancholy
rankings advanced, there was no dissimilarity among active and
sham stimulation.[28]
Conclusions
The findings of this study suggested that tDCS is an effective
modality for improving the overall quality of life in a patient
with DPN as it has a significant effect in reducing neuropathic
pain. Consequently, tDCS reduces anxiety and fatigue and
improves upper and lower limb functions with a direct effect on
applied cognition, general concern, and depression.

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Shereen H. ElSayed et al.:Assessment of the quality of life following transcranial direct current stimulation
12 Journal of Advanced Pharmacy Education & Research | Jan-Mar 2020 | Vol 10 | Issue 1
Acknowledgment
This research was funded by the Deanship of Scientific Research
at Princess Nourah bint Abdulrahman University through the
Fast-track Research Funding Program.
Conflict of interest
The authors state no conflict of interest.
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