The Effect of Light Therapy on Chronic Pain
The Effect of Light Therapy on Chronic Pain
Chronic pain is a major problem in the USA and the rest of the world, currently, all
 available pharmacological interventions carry with them significant side effects. Pain
 clinics are specially equipped to perform intentional pain procedures to manage pain.
 However, there remain groups of patients what neither benefit from pharmacological nor from
 interventional pain procedures. Other methods have shown only minor benefits such as hypnosis
 or cognitive behavioral therapy. Therefore, other techniques need to be investigated.

 Light therapy has been shown to have significant biological effects on humans. For example,
 light therapy is used to manage depression. Several clinical trials have shown that certain
 wavelengths of light can improve wound healing, decrease temporomandibular joint dysfunction
 (TMJ) pain, and decrease fear of back pain. In these trials, light was directed at the site
 of pain. In an attempt to better understand the effect of different wavelengths of light,
 pre-clinical studies were conducted using rats. The investigators have shown green and blue
 Light emitting diode, (LED) light produced antinociception (analgesia) and reversed
 neuropathic pain associated with several models of chronic pain. The analgesic effect of
 light was completely blocked when rats had their eyes covered, this suggests that the
 analgesic effects seen are mainly due to systemic effect through the visual system.

 Preliminary experiments on rats suggest that this effect is mediated through the endogenous
 opioids and cannabinoid system.

 The investigators believe that LED light is a safe alternative to pharmacological
 intervention to manage pain by stimulating the endogenous endorphin and cannabinoid systems.
 The investigators initial target participants with history of HIV, chemotherapy induced
 peripheral neuropathy and fibromyalgia. Participants will be divided into 2 groups. The first
 group will be a control group exposed to white LED light. The second group will be exposed to
 green LED light, respectively. Participants will be asked to take LED light home and will be
 asked to set in a dark room for 2 hours daily for 3 months with their LED light on. At the
 end of the 3 months trial, the investigator will assess their pain intensity, analgesic use,
 and overall quality of life. The investigators hypothesis is that participants exposed to
 green and blue light will have less use of analgesics and will have better life quality.
During the initial visit, the investigator will collect several pieces of data from
 participants that are considered part of the routine care, if you are being seen in the
 clinic, this information will also be used for research purposes. Initially the investigator
 will ask participants to provide their age, gender, work status, disability status, type of
 work, whether a previous pain physician has evaluated or provided treatment in the past, if
 there is any ongoing litigation, a detailed description of the pain (burning, electrical,
 shooting…etc.) and its location. If the participants are being seen in the clinic for their
 normal care a detailed physical examination assessing the motor strength of the upper
 extremities, sensation to light touch and reflexes that is part of the standard of care will
 be provided for the participants. The participants will be asked to give a numerical value
 for their pain (a scale from 0-10 where 0 is no pain and 10 is the worst pain imagined). Two
 questionnaires will be provided for the participants to complete which are not standard of
 care. The first one is the EuroQol Group (EQ-5D) which provide an over assessment of the
 quality of life. The second is a medication log to document their analgesics use. If the
 participants are being evaluated via telephone call, the same questions will be conducted,
 but no physical exam will be provided.

 The participants will be assigned to either a white, or green light group. The participants
 have 50% chance of being in either group. Once the participants are assigned a light group,
 the participants will be given a strip of Light emitting diode, (LED) light that correspond
 to their color group. The participants will be asked to take and use the LED strip in a dark
 room in their house every day for two hours to be exposed to the light, the participants will
 do this for 10 weeks. The study start date and the outcome assessment timeline will begin
 from the date of your first exposure to the assigned light. The participants will be asked to
 complete their weekly questionnaires and daily log, these will be given to the participants
 on their first clinic visit or sent to the participants if they live out of town. There will
 be several follow up appointments as detailed below. There is a chance the participants may
 be asked to cross over into a different group from the one the participants were assigned,
 there will we a 2 week washout period, then return to clinic for light assignment then light
 exposure for 10 week, similar visits as described below.

 For the follow up clinic visit or phone call (Week 10), data similar to the information
 gathered at the initial visit will be collected. The description of the pain (burning,
 electrical, shooting…etc.) and its location will be reviewed. A physical examination
 assessing for pain and sensation to light touch that is part of the standard of care will be
 provided for the participants. At the end of the study, the participants will be asked to
 return the LED strip, their logs and questionnaires.

 There is an optional blood draw and saliva sample collection for patients that consent to
 this. Blood and saliva samples will be collected at baseline and end of study, blood draws
 will be done to look for inflammatory mediators, increased anti inflammatory mediators and
 endocannabinoids. Saliva samples will be collected to check for melatonin.
Inclusion Criteria:

 -  Adults ages 18 - 80 able to understand English and comply with study protocol

 -  Peripheral neuropathy from HIV or chemotherapy.

 -  History of fibromyalgia

 -  Headaches

 -  Chronic Pain

 -  7-day average numeric pain score of 5/10 or greater at baseline evaluation

 Exclusion Criteria:

 -  Subjects receiving remuneration for their pain treatment

 -  Subjects that are incarcerated

 -  Subjects unable to read English and complete assessments

 -  Addictive behavior, severe clinical depression, or psychotic features