Clinical trial NCT01462448: Study to Identify the Genetic Variations Associated With Phantom Limb Pain
Official title: Study to Identify the Genetic Variations Associated With Phantom Limb Pain
Study type: OBSERVATIONAL
Overall status: UNKNOWN
Conditions: Phantom Limb
Keywords: Phantom Limb
Genetic Variation
DNA Sequence Analysis
Amputation, Traumatic
Single Nucleotide Polymorphism
Visual Analog Pain Scale
Brain-Derived Neurotrophic Factor
Inflammatory Antibody
Peripheral Nerve Damage
Lead sponsor: Henry M. Jackson Foundation for the Advancement of Military Medicine
Sponsor class: OTHER
Collaborators: name: Uniformed Services University of the Health Sciences
First posted: 2011-10-31
Enrollment: 726
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: CASE_CONTROL
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Subjects to be recruited at WRNMMC will be military health care beneficiaries age 18 and older who have sustained one or more amputations.

Brief summary: The purpose of this study is to determine if there is a genetic component to phantom limb pain. DNA will be analyzed for single nucleotide polymorphisms (SNPs) between the control and phantom limb pain group. Total RNA will also be isolated and profiled to asses the degree to which our gene(s) of interest are expressed in the presence or absence of phantom limb pain. Some proteins, such as inflammatory antibodies or the neurotrophin brain-derived neurotrophic factor (BDNF), will also be assessed for their association(s) with phantom limb pain.

Detailed description: Most patients (90-95%)with major limb amputations experience a phantom limb--the vivid impression that the limb is still present. In many cases, the sensation is painful for reasons that are currently not well understood. A small subset of amputees (\<10%) never experience phantom limb pain (PLP), the painful sensation felt in the amputated limb. This difference suggests that there may be a genetic component that precludes some patients from ever experiencing PLP. Understanding the genetic components of PLP may help in predicting which patients will experience PLP and which amputees will respond to the various treatment options available.

In order to understand the genetic aspects and ultimately develop more effective treatment options in the future, patients with and without PLP will be asked to give 30 mls of blood after overnight fasting. These blood samples will be de-identified and sent to the National Institutes of Health (NIH) in Bethesda, Maryland, where all of the genetic analyses will take place.

Eligibility criteria: Chronic PLP Group:

* At least 18 years of age.
* Written informed consent and written authorization for use or release of health and research study information
* Single or multiple upper and/or lower limb amputation
* At least three months post-amputation
* Ability to follow study instructions and likely to complete required visit(s)
* Experienced PLP for at least one month and at least 3 times per week
* Phantom limb pain differentiated from residual limb pain by physical exam.
* Subjects taking blood thinners or other medications that do not increase risk during a blood draw.

Non-Chronic PLP Group:

* At least 18 years of age.
* Written informed consent and written authorization for use or release of health and research study information
* Single or multiple upper and/or lower limb(s) amputation
* At least three months post-amputation
* Ability to follow study instructions and likely to complete required visit(s)
* Experienced PLP less than 10 times total and/or for less than two weeks
* Subjects taking blood thinners or other medications that do not increase risk during a blood draw.

Primary outcomes:
measure: Identification of Unique Single Nucleotides Polymorphisms (SNPs) associated with Phantom Limb Pain (PLP)
timeFrame: 5 years
Secondary outcomes:
measure: Correlation between Phantom Limb Pain (PLP) and Blood Levels of Antibodies Associated with Peripheral Nerve Damage
timeFrame: 5 years
measure: Correlation between Phantom Limb Pain (PLP) and Serum Levels of Brain-derived Neurotrophic Factor (BDNF)
timeFrame: 5 years
measure: Correlation between Phantom Limb Pain (PLP) and Unique Transcribed RNA
timeFrame: 5 years
Other outcomes:
Locations:
city: Bethesda
country: United States
facility: Walter Reed National Military Medical Center (WRNMMC)
state: Maryland
Study officials:
affiliation: Walter Reed National Military Medical Center (WRNMMC)
name: Paul F. Pasquina, MD, MC
role: PRINCIPAL_INVESTIGATOR
References:
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