Transcranial Direct Current Stimulation for Treating Parkinson´s Disease-related Pain in OFF State

NCT ID: NCT06214377

Last Updated: 2024-05-08

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Clinical Phase

NA

Total Enrollment

15 participants

Study Classification

INTERVENTIONAL

Study Start Date

2023-07-01

Study Completion Date

2024-04-11

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

Parkinson's Disease (PD) is a neurodegenerative disorder characterized by motor and non-motor symptoms. Pain is a significant symptom in PD, affecting a large percentage of patients and impacting their quality of life. The mechanisms of pain in PD involve complex changes in pain-modulating pathways, including dopaminergic and non-dopaminergic systems.

To address the lack of pain management strategies, the investigators propose exploring non-pharmacological therapies like transcranial direct current stimulation (tDCS). tDCS is a safe and non-invasive technique that modulates neuronal activity. It has shown positive effects on pain processing in healthy individuals and chronic pain patients, but its potential for PD-associated pain remains largely unexplored.

The primary motor cortex (M1) is a target for tDCS as it is believed to influence pain processing in other brain regions involved in sensory and emotional aspects. Initial studies suggest the benefits of tDCS in PD, including enhanced motor potentials and potential modulation of dopaminergic pathways. However, there are currently no published studies specifically investigating the effects of tDCS on PD-related pain, highlighting the need for further research.

A proof-of-concept trial is proposed to examine the effects of a single tDCS session on M1 in PD patients during the OFF state (without medication) and after taking dopaminergic medication. The study aims to assess the pain-relieving effects of tDCS in PD and explore potential synergies between tDCS and dopaminergic medication. By better understanding the impact of tDCS on pain relief in PD, this research may offer insights into alternative non-pharmacological approaches for managing pain in PD.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Parkinson's Disease (PD) is a complex progressive neurodegenerative disorder. It is the second most common neurodegenerative disease, with a prevalence of 4.1 to 4.6 million people over the age of 50. It is estimated that these numbers will increase to 8.7 to 9.3 million by the year 2030.

PD is multisystemic and include both motor and non-motor symptoms. These symptoms can fluctuate throughout the day, leading PD patients to frequently experience two distinct states: the "on" state, when dopaminergic medication is active in their system, and the "off" state, which occurs when there is no medication concentration in the body, resulting in more severe symptoms.

Pain in PD is a highly relevant symptom that significantly impacts patients' quality of life, with a prevalence of up to 85% and moderate to severe intensity reported in 42% of individuals. Additionally, in Spain, the prevalence of PD-associated pain has significantly increased following the COVID-19 pandemic, with up to 50% of PD patients reporting daily pain. Moreover, pain in PD is often underreported, emphasizing the need to investigate its mechanisms and treatment.

The pathophysiological mechanisms of pain in PD are complex. In general, PD can lead to alterations in peripheral transmission, sensory-discriminative processing, pain perception, and interpretation at multiple levels, due to neurodegenerative changes in both dopaminergic and non-dopaminergic pain-modulating pathways. This dysregulation of the dopaminergic system can impact the experience of pain directly by enhancing nociceptive signals and indirectly by influencing expectations and the interpretation of such signals. However, it is considered that there is no specific pain center in PD patients but rather a pain matrix involving various brain structures.

Given the multiple central structures affected and their consequent pathophysiological mechanisms in PD-associated pain, there is a wide variety of clinical manifestations. These include musculoskeletal pain, generalized central chronic pain, visceral pain, pain related to "on-off" fluctuations, dystonic-dyskinetic pain, nocturnal immobility-related pain or restless legs syndrome, orofacial pain, inflammation or edema-related pain, and radicular pain.

Regarding the assessment of pain in PD, there is only one specific scale that evaluates all pain phenotypes of the disease in terms of intensity and frequency, namely the King's Parkinson's Disease Pain Scale (KPPS). Therefore, due to the scarcity of objective pain assessment tools and the crucial role of the central nervous system and endogenous modulation systems in the origin of PD-associated pain, it is important to assess pain processing characteristics such as Conditioned Pain Modulation (CPM), and Pressure Pain Thresholds (PPTs). CPM assesses the descending inhibitory pain system, and PPTs assess the intensity of pressure required to elicit initial pain in a specific body area.

Dopaminergic medication is the primary treatment for PD symptoms; however, its effects on pain management have shown contradictory results according to recent systematic reviews. Moreover, there is currently a lack of robust evidence to establish guidelines for pain management in PD, which is why non-pharmacological therapies have been proposed as a safe and useful alternative with fewer side effects.

Transcranial Direct Current Stimulation (tDCS) is a non-invasive form of brain stimulation in which a relatively weak continuous current is delivered to the cortical areas through small electrodes placed on the scalp. It is a neuromodulatory intervention, and based on the assumption that the exposed tissue is polarized, tDCS would modulate neuronal excitability by depolarizing or hyperpolarizing the resting membrane potential of neurons. This modulation would result in increases or decreases in cortical excitability, depending on whether the active electrode is the anode or the cathode, respectively.

tDCS has been shown to have an effect on certain psychophysical variables of pain processing in healthy subjects. It has primarily been shown to enhance CPM and improvements have been reported in PPTs, cold and heat pain thresholds, acute pain induced by laser (26), and pain threshold after peripheral electrical stimulation. Importantly, tDCS has also demonstrated beneficial effects in patients with chronic pain. Specifically, it has shown improvements in pain processing characteristics, resulting in clinical pain improvements in other populations with chronic neuropathic pain. It is hypothesized that tDCS could be an effective alternative in the treatment of pain with central sensitization components, a process common in PD-associated pain.

The majority of the hypoalgesic effects generated by tDCS are due to its modulation of the primary motor cortex (M1). It is suggested that tDCS over M1 could reduce pain by increasing excitability not only in the stimulated area but also in other structures involved in pain processing, both sensory and emotional, through cortico-subcortical connectivity.

However, there are currently no published studies applying tDCS for the treatment of PD-associated pain, except for unpublished studies from our group confirming a favorable effect in this regard. Nonetheless, disregarding our results, its use can be considered safe as it has already been tested in PD patients for other purposes. tDCS has demonstrated an influence on Motor Evoked Potentials (MEPs) in PD patients, increasing MEPs after stimulating M1 with an active anode and decreasing MEPs with an active cathode. Furthermore, it has been observed that bilateral tDCS with an active anode leads to increases in BDNF, thus slowing down the degeneration of dopaminergic neurons. This last piece of evidence, along with other findings that demonstrate the capacity of tDCS to modulate dopaminergic transmission, is relevant for the present project, considering that part of the descending inhibitory pain system involves these pathways. Similarly, it has been demonstrated that pain causes reductions in corticomotor excitability, governed by M1, and tDCS applied to M1 has shown the ability to increase cortical excitability, which has abnormal activity in PD patients and could influence their pain.

Given the overlap between many influential areas in PD-associated pain and the areas excited by tDCS over M1, with these increases in excitability correlating with pain reduction, as well as the potential effect of tDCS on dopaminergic pathways, a hypoalgesic effect of tDCS in PD patients in their OFF state is hypothesized. Additionally, if the action is based on the activation of dopaminergic pathways, a possible enhancement of dopaminergic medication's action with better pain control during the ON period is also expected. However, there is currently no study that has specifically evaluated this effect in PD patients in the OFF state, making it pertinent to conduct a proof-of-concept trial with this objective. The objective is to determine the effect of a single session of treatment using transcranial direct current stimulation (tDCS) on the primary motor cortex (M1) on perceived clinical pain and pain processing characteristics in patients with Parkinson's disease (PD) in the OFF state (without dopaminergic medication) and after taking dopaminergic medication.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Parkinson Disease Pain

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

RANDOMIZED

Intervention Model

CROSSOVER

This study will be a triple-blinded experimental randomized controlled trial with a crossover design. The randomization will be conducted through the "GraphPad" software by an independent investigator. All the participants who fulfill the inclusion criteria and have none of the exclusion ones will be randomly allocated into two groups (depending on the order of the intervention allocation): 1.active-tDCS-2.shamtDCS or 1.sham-tDCS-2.active-tDCS. Allocation concealment will be ensured by the inclusion of the assigned group in closed opaque envelopes that will be opened at the time of the first intervention.
Primary Study Purpose

TREATMENT

Blinding Strategy

QUADRUPLE

Participants Caregivers Investigators Outcome Assessors
Triple-blind criteria will be achieved by identic collocation of the electrodes in both conditions and by activating the "double-blind" option in the Starstim tDCS® Software (Neuroelectrics Inc, Barcelona, Spain) that allows concealing the protocol by writing a neutral number. The evaluator, not allowed to stay in the same room while the interventions, will conceal the protocols with the neutral number and the therapist will read it in the envelope, ignoring which number coincides with each intervention. At the end of the second session, patients will be asked whether they received the order 1.active-2.sham or 1.sham-2.active, to assess the blinding success. The statistician will also be blinded through the mentioned neutral numbers. Unblinding will be permissible when any event could suppose a risk to the patient's health.

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Active Transcranial Direct Current Stimulation and dopaminergic medication

Active Transcranial Direct Current Stimulation (atDCS) will be applied over the Primary Motor Cortex (M1) contralateral to pain if it is unilateral, or always on the left M1 if pain is bilateral. It will consist of 1 session of 20 minutes of conventional stimulation (anode over M1) at 2 mA. It will be applied in the OFF state (i.e., \>12h after the last medication intake). Lately, patients will take its usual dopaminergic medication.

Group Type EXPERIMENTAL

Sham Transcranial Direct Current Stimulation

Intervention Type DEVICE

The Starstim tCS® equipment (Neuroelectrics Inc, Barcelona, Spain) will be used with 35 cm2 sponge electrodes. The tDCS sham over M1 will be performed by placing the electrodes in the same position as in the active tDCS protocol. However, the stimulator will automatically turn off after 30 seconds of stimulation, making it a reliable sham stimulation method. Therefore, subjects will feel the same tingling sensation but will not receive current for the remainder of the stimulation time.

Dopaminergic medication

Intervention Type DRUG

After tDCS, the participant will take their regular dopaminergic medication in order to go from OFF state to ON state.

Active Transcranial Direct Current Stimulation

Intervention Type DEVICE

The Starstim tCS® equipment will be used, with 35 cm2 sponge electrodes. The tDCS over M1 will be performed by placing the active anode on the C3 point (10/20 EEG system) and the cathode on the contralateral supraorbital area (Fp2). Regarding the stimulated hemisphere, in cases of asymmetric pain, it will be applied to the contralateral M1, and in cases of bilateral pain, it will be applied to the M1 of the dominant hemisphere. A constant current of 2 mA (subthreshold intensity) will be applied for 20 minutes, with the first 30 seconds used as a ramp-up and the last 30 seconds as a ramp-down. Number of sessions: 1.

: Sham Transcranial Direct Current Stimulation and dopaminergic medication

Sham Transcranial Direct Current (s-tDCS) will be applied over the Primary Motor Cortex with the same procedure, during 1 session of 20 minutes of conventional stimulation. It will be applied in the OFF state (i.e., \>12h after the last medication intake). Lately, patients will take its usual dopaminergic medication.

Group Type SHAM_COMPARATOR

Sham Transcranial Direct Current Stimulation

Intervention Type DEVICE

The Starstim tCS® equipment (Neuroelectrics Inc, Barcelona, Spain) will be used with 35 cm2 sponge electrodes. The tDCS sham over M1 will be performed by placing the electrodes in the same position as in the active tDCS protocol. However, the stimulator will automatically turn off after 30 seconds of stimulation, making it a reliable sham stimulation method. Therefore, subjects will feel the same tingling sensation but will not receive current for the remainder of the stimulation time.

Dopaminergic medication

Intervention Type DRUG

After tDCS, the participant will take their regular dopaminergic medication in order to go from OFF state to ON state.

Active Transcranial Direct Current Stimulation

Intervention Type DEVICE

The Starstim tCS® equipment will be used, with 35 cm2 sponge electrodes. The tDCS over M1 will be performed by placing the active anode on the C3 point (10/20 EEG system) and the cathode on the contralateral supraorbital area (Fp2). Regarding the stimulated hemisphere, in cases of asymmetric pain, it will be applied to the contralateral M1, and in cases of bilateral pain, it will be applied to the M1 of the dominant hemisphere. A constant current of 2 mA (subthreshold intensity) will be applied for 20 minutes, with the first 30 seconds used as a ramp-up and the last 30 seconds as a ramp-down. Number of sessions: 1.

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Sham Transcranial Direct Current Stimulation

The Starstim tCS® equipment (Neuroelectrics Inc, Barcelona, Spain) will be used with 35 cm2 sponge electrodes. The tDCS sham over M1 will be performed by placing the electrodes in the same position as in the active tDCS protocol. However, the stimulator will automatically turn off after 30 seconds of stimulation, making it a reliable sham stimulation method. Therefore, subjects will feel the same tingling sensation but will not receive current for the remainder of the stimulation time.

Intervention Type DEVICE

Dopaminergic medication

After tDCS, the participant will take their regular dopaminergic medication in order to go from OFF state to ON state.

Intervention Type DRUG

Active Transcranial Direct Current Stimulation

The Starstim tCS® equipment will be used, with 35 cm2 sponge electrodes. The tDCS over M1 will be performed by placing the active anode on the C3 point (10/20 EEG system) and the cathode on the contralateral supraorbital area (Fp2). Regarding the stimulated hemisphere, in cases of asymmetric pain, it will be applied to the contralateral M1, and in cases of bilateral pain, it will be applied to the M1 of the dominant hemisphere. A constant current of 2 mA (subthreshold intensity) will be applied for 20 minutes, with the first 30 seconds used as a ramp-up and the last 30 seconds as a ramp-down. Number of sessions: 1.

Intervention Type DEVICE

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* Diagnosis of Idiopathic Parkinson´s Disease.
* Presence of Parkinson´s Disease-related pain in the off-state.
* Neuroimaging study without previous pathologies.
* Score \> 5 in transfers (bed to chair and back) item in Barthel Index.
* Score = or \> 26 in Montreal Cognitive Assessment (MoCA).
* Tolerability for the application of electrotherapy.
* Able to provide informed consent to participate in the study
* Pain intensity \>= 3 in Visual Analogue Scale or equivalent.

Exclusion Criteria

* Neurologic disease different from PD.
* Pain non-related to PD.
* Dermatologic problems, wounds, or ulcers in the electrode's application area.
* Presence of implants or metal pieces in the head.
* Presence of cardiac pacemaker, vagal, brain or transcutaneous stimulators, medication pumps, ventriculoperitoneal shunts or aneurysm clips.
* Significative difficulties in language.
* History of alcohol or drugs abuse.
* Non-controlled medical problems.
* Pregnancy.
* Epilepsy
Minimum Eligible Age

18 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

Universidad Rey Juan Carlos

OTHER

Sponsor Role collaborator

Hospital Beata María Ana

OTHER

Sponsor Role collaborator

Universidad Francisco de Vitoria

OTHER

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Responsibility Role SPONSOR

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

Juan Pablo Romero, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Universidad Francisco de Vitoria, Facultad de Ciencias Experimentales

Josué Fernández Carnero, PT, PhD

Role: PRINCIPAL_INVESTIGATOR

Universidad Rey Juan Carlos

Marcos Moreno Verdú, PT, PhD

Role: PRINCIPAL_INVESTIGATOR

Universidad Francisco de Vitoria

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

Hospital Beata Maria Ana

Madrid, , Spain

Site Status

Countries

Review the countries where the study has at least one active or historical site.

Spain

References

Explore related publications, articles, or registry entries linked to this study.

Kalia LV, Lang AE. Parkinson's disease. Lancet. 2015 Aug 29;386(9996):896-912. doi: 10.1016/S0140-6736(14)61393-3. Epub 2015 Apr 19.

Reference Type RESULT
PMID: 25904081 (View on PubMed)

Silverdale MA, Kobylecki C, Kass-Iliyya L, Martinez-Martin P, Lawton M, Cotterill S, Chaudhuri KR, Morris H, Baig F, Williams N, Hubbard L, Hu MT, Grosset DG; UK Parkinson's Pain Study Collaboration. A detailed clinical study of pain in 1957 participants with early/moderate Parkinson's disease. Parkinsonism Relat Disord. 2018 Nov;56:27-32. doi: 10.1016/j.parkreldis.2018.06.001. Epub 2018 Jun 6.

Reference Type RESULT
PMID: 29903584 (View on PubMed)

Antonini A, Tinazzi M, Abbruzzese G, Berardelli A, Chaudhuri KR, Defazio G, Ferreira J, Martinez-Martin P, Trenkwalder C, Rascol O. Pain in Parkinson's disease: facts and uncertainties. Eur J Neurol. 2018 Jul;25(7):917-e69. doi: 10.1111/ene.13624. Epub 2018 Apr 18.

Reference Type RESULT
PMID: 29520899 (View on PubMed)

Lefaucheur JP, Antal A, Ayache SS, Benninger DH, Brunelin J, Cogiamanian F, Cotelli M, De Ridder D, Ferrucci R, Langguth B, Marangolo P, Mylius V, Nitsche MA, Padberg F, Palm U, Poulet E, Priori A, Rossi S, Schecklmann M, Vanneste S, Ziemann U, Garcia-Larrea L, Paulus W. Evidence-based guidelines on the therapeutic use of transcranial direct current stimulation (tDCS). Clin Neurophysiol. 2017 Jan;128(1):56-92. doi: 10.1016/j.clinph.2016.10.087. Epub 2016 Oct 29.

Reference Type RESULT
PMID: 27866120 (View on PubMed)

Fregni F, Boggio PS, Santos MC, Lima M, Vieira AL, Rigonatti SP, Silva MT, Barbosa ER, Nitsche MA, Pascual-Leone A. Noninvasive cortical stimulation with transcranial direct current stimulation in Parkinson's disease. Mov Disord. 2006 Oct;21(10):1693-702. doi: 10.1002/mds.21012.

Reference Type RESULT
PMID: 16817194 (View on PubMed)

Fregni F, Boggio PS, Lima MC, Ferreira MJ, Wagner T, Rigonatti SP, Castro AW, Souza DR, Riberto M, Freedman SD, Nitsche MA, Pascual-Leone A. A sham-controlled, phase II trial of transcranial direct current stimulation for the treatment of central pain in traumatic spinal cord injury. Pain. 2006 May;122(1-2):197-209. doi: 10.1016/j.pain.2006.02.023. Epub 2006 Mar 27.

Reference Type RESULT
PMID: 16564618 (View on PubMed)

Chaudhuri KR, Rizos A, Trenkwalder C, Rascol O, Pal S, Martino D, Carroll C, Paviour D, Falup-Pecurariu C, Kessel B, Silverdale M, Todorova A, Sauerbier A, Odin P, Antonini A, Martinez-Martin P; EUROPAR and the IPMDS Non Motor PD Study Group. King's Parkinson's disease pain scale, the first scale for pain in PD: An international validation. Mov Disord. 2015 Oct;30(12):1623-31. doi: 10.1002/mds.26270. Epub 2015 Jun 11.

Reference Type RESULT
PMID: 26096067 (View on PubMed)

Perez-Lloret S, Ciampi de Andrade D, Lyons KE, Rodriguez-Blazquez C, Chaudhuri KR, Deuschl G, Cruccu G, Sampaio C, Goetz CG, Schrag A, Martinez-Martin P, Stebbins G; Members of the MDS Committee on Rating Scales Development. Rating Scales for Pain in Parkinson's Disease: Critique and Recommendations. Mov Disord Clin Pract. 2016 Jun 24;3(6):527-537. doi: 10.1002/mdc3.12384. eCollection 2016 Nov-Dec.

Reference Type RESULT
PMID: 30363588 (View on PubMed)

Imai Y, Petersen KK, Morch CD, Arendt Nielsen L. Comparing test-retest reliability and magnitude of conditioned pain modulation using different combinations of test and conditioning stimuli. Somatosens Mot Res. 2016 Sep-Dec;33(3-4):169-177. doi: 10.1080/08990220.2016.1229178. Epub 2016 Sep 20.

Reference Type RESULT
PMID: 27650216 (View on PubMed)

Santos-Garcia D, Oreiro M, Perez P, Fanjul G, Paz Gonzalez JM, Feal Painceiras MJ, Cores Bartolome C, Valdes Aymerich L, Garcia Sancho C, Castellanos Rodrigo MDM. Impact of Coronavirus Disease 2019 Pandemic on Parkinson's Disease: A Cross-Sectional Survey of 568 Spanish Patients. Mov Disord. 2020 Oct;35(10):1712-1716. doi: 10.1002/mds.28261. Epub 2020 Sep 22.

Reference Type RESULT
PMID: 32776601 (View on PubMed)

Gonzalez-Zamorano Y, Moreno-Verdu M, Martinez-Benito A, Fernandez-Carnero J, Romero JP. Transcranial Direct Current Stimulation in Parkinson's Disease Patients in the Off State: A Randomized Controlled Crossover Trial Examining the Effects on Pain With and Without the Influence of Dopaminergic Medication. Pain Pract. 2025 Nov;25(8):e70082. doi: 10.1111/papr.70082.

Reference Type DERIVED
PMID: 41039704 (View on PubMed)

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

ParkOFF-tDCS

Identifier Type: -

Identifier Source: org_study_id

More Related Trials

Additional clinical trials that may be relevant based on similarity analysis.