Clinical trial NCT01863017: Pilot Study of Startle-response Test to Assess Transcranial Direct Current Stimulation-induced Modulation of Hyperphagia in Prader-Willi Syndrome
Official title: Pilot Study of Startle-response Test to Assess Transcranial Direct Current Stimulation- Induced Modulation of Hyperphagia in Prader-Willi Syndrome
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Hyperphagia
Prader-Willi Syndrome
Keywords: Obesity
Over weight
Lead sponsor: University of Kansas Medical Center
Sponsor class: OTHER
Collaborators: name: Prader-Willi Syndrome Association USA
name: Harvard Medical School (HMS and HSDM)
name: Foundation for Prader-Willi Research
First posted: 2013-05-27
Enrollment: 31
Sex: ALL
Minimum age (years): 18
Maximum age (years): 64
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The purpose of this study is to determine the effects of transcranial direct current stimulation (tDCS) as it modifies hyperphagia in obese subjects, non-obese subjects, and subjects with Prader-Willi syndrome (PWS).

Detailed description: PWS is characterized by hypotonia, feeding difficulties, developmental delay and failure to thrive during infancy, and by an insatiable appetite (hyperphagia), rapid weight gain and obesity in early childhood.

Hyperphagia is one of the most prominent and debilitating features of PWS, and currently no pharmaceutical drug has been successful in decreasing appetite in such patients.

tDCS is a safe, noninvasive method whereby a weak electric current is directly transmitted into the brain via external electrodes connected to a 9-volt radio battery. It is based on decades-old observations that nerve cell firing can be altered by low amplitude direct current (DC). The researchers in this study believe that tDCS may have a positive impact on hyperphagia and weight.

In this study, the investigators intend to assess whether the effects tDCS differ between obese subjects, non-obese subjects, and subjects with Prader-Willi syndrome by measuring the amplitude and latency of eyeblink startle responses to a set of food- and non-food-related visual stimuli in all subjects, various hyperphagia questionnaires, and cognitive and behavioral assessments. It is hypothesized that as a group, subjects with Prader-Willi syndrome will demonstrate behavioral and psychometric evidence of abnormal food image processing, craving and associated behaviors relative to our control groups, and this group may receive potentially beneficial effects from tDCS sessions. Obese subjects are also predicted to have decreased hyperphagia and food cravings as a result of tDCS.

Eligibility criteria: Inclusion Criteria:

* Healthy individuals and individuals diagnosed with Prader-Willi syndrome
* Provide informed consent to participate in the study
* Body Mass Index (BMI) \<25kg/m2 (for non-obese subjects only)
* Body Mass Index (BMI) ≥30kg/m2 (for obese subjects only)

Exclusion Criteria:

* Subject is pregnant at time of enrollment in the study.
* Contraindications to tDCS:

  1. metal in the head
  2. implanted brain medical devices
* Clinically significant and unstable medical disorders (e.g., uncontrolled diabetes, uncompensated cardiac issues, heart failure, pulmonary issues, or chronic obstructive pulmonary disease) as self-reported.
* Clinically significant and unstable psychiatric disorders (e.g., schizophrenia, schizoaffective disorder, other psychosis, bipolar illness, severe depression) as self-reported.
* Significant visual impairment, as self-reported
* History of auditory deficiencies, as self-reported
* History of alcohol or substance abuse within the last 6 months as self-reported
* Use of carbamazepine within the past 6 months as self-reported.
* Current use of antidepressants
* History of neurological disorders as self-reported
* History of neurosurgery as self-reported

Primary outcomes:
measure: Amplitude of Eyeblink Startle Responses
timeFrame: Amplitude of Eyeblink Startle at Day 30 relative to normal weight controls
measure: Dykens Hyperphagia Questionnaire
timeFrame: Total Score Day 30
Secondary outcomes:
measure: Three-Factor Eating Questionnaire
timeFrame: Total Scores at Day 30
Other outcomes:
Locations:
city: Kansas City
country: United States
facility: University of Kansas Medical Center
state: Kansas
city: Boston
country: United States
facility: Spaulding Rehabilitation Hospital
state: Massachusetts
city: Dousman
country: United States
facility: Prader-Willi Homes of Oconomowoc
state: Wisconsin
Study officials:
affiliation: University of Kansas Medical Center
name: Merlin G. Butler, MD, PhD
role: PRINCIPAL_INVESTIGATOR
affiliation: Spaulding Rehabilitation Hospital
name: Felipe Fregni, MD, PhD, MPH
role: PRINCIPAL_INVESTIGATOR
References:
citation: Bravo GL, Poje AB, Perissinotti I, Marcondes BF, Villamar MF, Manzardo AM, Luque L, LePage JF, Stafford D, Fregni F, Butler MG. Transcranial direct current stimulation reduces food-craving and measures of hyperphagia behavior in participants with Prader-Willi syndrome. Am J Med Genet B Neuropsychiatr Genet. 2016 Mar;171B(2):266-75. doi: 10.1002/ajmg.b.32401. Epub 2015 Nov 21.