Far Red Light Therapy for Peripheral Arterial Disease
(LIGHT PAD Trial)
Recruiting in Palo Alto (17 mi)
Age: 18+
Sex: Any
Travel: May Be Covered
Time Reimbursement: Varies
Trial Phase: Academic
Recruiting
Sponsor: Northwestern University
Disqualifiers: Amputation, Critical limb ischemia, Wheelchair, others
No Placebo Group
Trial Summary
What is the purpose of this trial?The LIGHT PAD Trial is a Phase II multi-centered randomized clinical trial to collect preliminary data to test whether daily far red light treatment of the lower extremities in people with PAD improves six-minute walk distance, lower extremity perfusion, and ischemia-related damage in gastrocnemius muscle at four-month follow-up, compared to a sham control. Participants will complete 10 minutes of twice daily home treatment with either far red light or a sham light for four months.
Will I have to stop taking my current medications?
The trial information does not specify whether you need to stop taking your current medications. It is best to discuss this with the trial coordinators or your doctor.
What data supports the effectiveness of Far Red Light Therapy for Peripheral Arterial Disease?
Research shows that light therapy, including red and near-infrared light, can increase blood flow by generating nitric oxide, which helps widen blood vessels. This effect has been observed in studies involving both animals and humans, suggesting potential benefits for conditions like Peripheral Arterial Disease where improved circulation is needed.
12345Is Far Red Light Therapy safe for humans?
Far Red Light Therapy, also known as low-level laser therapy, has been used safely in various medical fields like dentistry, physiotherapy, and cardiology for over forty years. It is generally considered safe, with studies showing positive effects on healing and reducing inflammation, although the exact mechanisms are not fully understood.
36789How does Far Red Light Therapy differ from other treatments for Peripheral Arterial Disease?
Far Red Light Therapy is unique because it uses light to improve blood flow and stimulate healing, unlike traditional medical or surgical treatments. This therapy, known as photobiomodulation, can be self-administered and has no reported side effects, making it a novel approach for managing conditions like Peripheral Arterial Disease.
123410Eligibility Criteria
This trial is for people over 50 with Peripheral Arterial Disease (PAD), evidenced by specific tests. They must be able to walk without a walker or wheelchair, not have critical limb ischemia, recent major surgeries, severe medical conditions like advanced lung disease or Parkinson's, and should not be in another clinical trial recently.Inclusion Criteria
I am 50 years old or older.
I have been diagnosed with PAD based on specific tests and criteria.
Exclusion Criteria
I do not speak English.
I haven't had major surgery or significant heart issues in the last 3 months.
My walking is limited by a condition that is not related to leg artery disease.
+15 more
Trial Timeline
Screening
Participants are screened for eligibility to participate in the trial
2-4 weeks
Treatment
Participants receive daily far red light treatment or sham control for four months
16 weeks
Home treatment, twice daily
Follow-up
Participants are monitored for safety and effectiveness after treatment
4 weeks
Participant Groups
The LIGHT PAD Trial is testing if far red light therapy can improve walking distance and blood flow in the legs of PAD patients compared to a fake light treatment. Participants will use the assigned light device on their lower extremities at home for ten minutes twice daily over four months.
2Treatment groups
Experimental Treatment
Placebo Group
Group I: Far red light therapyExperimental Treatment1 Intervention
Subgroup of participants receiving the 670 nm far red light device
Group II: Sham therapyPlacebo Group1 Intervention
Subgroup of participants receiving the sham light device, far red light device covered with blue filter paper to block 670 nm light, resulting in mean power generated of 0.24 mW/cm2, compared to 26.3 mW/cm2 for the intervention, a 100-fold difference.
Find a Clinic Near You
Research Locations NearbySelect from list below to view details:
Northwestern UniversityChicago, IL
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Who Is Running the Clinical Trial?
Northwestern UniversityLead Sponsor
References
Perspective on Broad-Acting Clinical Physiological Effects of Photobiomodulation. [2019]Research into photobiomodulation reveals beneficial effects of light therapy for a rapidly expanding list of medical conditions and illnesses. Although it has become more widely accepted by the mainstream medicine, the effects and mechanisms of action appear to be poorly understood. The therapeutic benefits of photobiomodulation using low-energy red lasers extend far beyond superficial applications, with a well-described physics allowing an understanding of how red lasers of certain optimum intensities may cross the cranium. We now have a model for explaining potential therapeusis for applications in functional neurology that include stroke, traumatic brain injury, and neurodegenerative conditions in addition to the currently approved functions in lipolysis, in onychomycosis treatment, and in pain management.
Low-level laser treatment with near-infrared light increases venous nitric oxide levels acutely: a single-blind, randomized clinical trial of efficacy. [2016]The use of near-infrared light in the form of low-level laser therapy (LLLT) has become more popular in the treatment of a variety of conditions where increased peripheral blood flow is desired. The hypothesis behind its working mechanism is its purported ability to generate nitric oxide (NO) in the treated area. We tested the hypothesis that the efficacy of near-infrared light lies in its ability to generate NO at the treatment site.
Biological effect of far-infrared therapy on increasing skin microcirculation in rats. [2022]Insufficient microcirculation of skin leads to acute and chronic tissue ischemia in cases of trauma, reconstructive surgery, diabetes mellitus and peripheral arterial occlusive disease. The autonomic nervous system and nitric oxide (NO) play important roles in maintaining blood perfusion of the skin. Far-infrared (FIR) therapy provides low energy of light emitted from an artificial radiator and has been used to treat many vascular-related disorders. Nevertheless, the mechanisms through which FIR works remain unclear. The present study aims to test the hypothesis that the effect of FIR is through increasing skin microcirculation by a mechanism other than its thermal effect.
Photobiomodulation by light emitting diode applied sequentially does not alter performance in cycling athletes. [2020]Analyze the effects of sequential application of photobiomodulation therapy (PBMT) at different wavelengths on the performance of cycling athletes. Cyclists (48 male, mean age 33.77 years) underwent a performance evaluation through an incremental test, VO2max, blood lactate analysis, perception of effort, infrared thermography, and isokinetic evaluations. Photobiomodulation (180 J) with infrared (IR 940 ± 10 nm), red (RED 620 ± 10 nm), mixed Red, and IR (RED/IR 620 + 940 nm) or Sham (disabled device) intervention occurred on three consecutive days and was applied to the quadriceps femoris bilaterally. Reevaluations were performed 24 h after the last application, with 1 week of follow-up. A significance level of 5% was adopted, and the effect size (ES) was calculated by Cohen's d. Results: There were no significant differences in the analyzed variables under any experimental condition (p > 0.005), but a moderate effect size was observed for torque peak at 60°/s on left lower limb (LLL) (ES = 0.67), average power at 60°/s of the right lower limb (RLL) (0.73), and LLL (ES = 0.65) and a considerable effect size in torque peak at 60°/s of the RLL (ES = 0.98) in the IR/RED group compared with sham 24 h after the last application. Moreover, a large effect size was observed for total time to exhaustion (ES = 1.98) and for VO2max (ES = 6.96), and a moderate effect size was seen for anaerobic threshold (ES = 0.62) in the IR/RED group compared with sham. Photobiomodulation, when not associated with training, was not able to produce a cumulative effect on the performance of cycling athletes. However, the association of two wavelengths seems to be better for increased performance. ClinicalTrials.gov Identifier: NCT03225976.
In Vivo Characterization of a Red Light-Activated Vasodilation: A Photobiomodulation Study. [2023]Nitric oxide dependent vasodilation is an effective mechanism for restoring blood flow to ischemic tissues. Previously, we established an ex vivo murine model whereby red light (670 nm) facilitates vasodilation via an endothelium derived vasoactive species which contains a functional group that can be reduced to nitric oxide. In the present study we investigated this vasodilator in vivo by measuring blood flow with Laser Doppler Perfusion imaging in mice. The vasodilatory nitric oxide precursor was analyzed in plasma and muscle with triiodide-dependent chemiluminescence. First, a 5-10 min irradiation of a 3 cm2 area in the hind limb at 670 nm (50 mW/cm2) produced optimal vasodilation. The nitric oxide precursor in the irradiated quadriceps tissue decreased significantly from 123 ± 18 pmol/g tissue by both intensity and duration of light treatment to an average of 90 ± 17 pmol/g tissue, while stayed steady (137 ± 21 pmol/g tissue) in unexposed control hindlimb. Second, the blood flow remained elevated 30 min after termination of the light exposure. The nitric oxide precursor content significantly increased by 50% by irradiation then depleted in plasma, while remained stable in the hindlimb muscle. Third, to mimic human peripheral artery disease, an ameroid constrictor was inserted on the proximal femoral artery of mice and caused a significant reduction of flow. Repeated light treatment for 14 days achieved steady and significant increase of perfusion in the constricted limb. Our results strongly support 670 nm light can regulate dilation of conduit vessel by releasing a vasoactive nitric oxide precursor species and may offer a simple home-based therapy in the future to individuals with impaired blood flow in the leg.
Photobiomodulation in Periodontology and Implant Dentistry: Part 2. [2020](Part 1 of this article can be located at www.liebertpub.com/doi/10.1089/photob.2019.4710.) Objective: Finding evidence-based treatment strategies for low-level light therapy and the correct incorporation of these treatment methods in the clinical practice of periodontics. Background: Photobiomodulation has been shown to have biostimulatory, anti-inflammatory, and analgesic effects that can be beneficial in periodontal and dental implant treatment procedures. Methods: In this review, we have addressed some clinical questions regarding the potential clinical application of low-level light irradiation and its photobobiomodulatory effects in periodontology and implantology. The literature was searched for in vivo (animal or clinical) articles written in English in four electronic databases of PubMed, Scopus, Google Scholar, and Cochrane Library until April 2019. Only studies with low irradiation doses without any thermal effects used only for their photobiomodulatory purposes were included. Results: We were able to find relevant studies for all of our questions, and positive effects for the application of light therapy were reported in most of the studies. However, there is still a great deal of heterogeneity in terms of study designs and most importantly in light irradiation devices and the parameters used. Due to this issue, it was not possible to reach specific evidence-based irradiation protocols for the questions addressed in this review. Conclusions: Based on our search results, an obvious positive effect of low-level light therapy on stimulation of healing of periodontal soft and hard tissues and reduction of inflammation can be seen. Future well-designed randomized control studies with the same irradiation settings and systematic reviews evaluating the studies found on the questions mentioned are necessary to reach evidence-based recommendations.
Light-induced vasodilation of coronary arteries and its possible clinical implication. [2015]Low-level laser therapy and light-emitting diodes (LED) are increasingly used in phototherapy. Their therapeutic effects are at least partly mediated by light-induced vasodilation. The aim of this study was to determine the effect of different light sources on coronary arteries.
Biphasic dose response in low level light therapy. [2023]The use of low levels of visible or near infrared light for reducing pain, inflammation and edema, promoting healing of wounds, deeper tissues and nerves, and preventing cell death and tissue damage has been known for over forty years since the invention of lasers. Despite many reports of positive findings from experiments conducted in vitro, in animal models and in randomized controlled clinical trials, LLLT remains controversial in mainstream medicine. The biochemical mechanisms underlying the positive effects are incompletely understood, and the complexity of rationally choosing amongst a large number of illumination parameters such as wavelength, fluence, power density, pulse structure and treatment timing has led to the publication of a number of negative studies as well as many positive ones. A biphasic dose response has been frequently observed where low levels of light have a much better effect on stimulating and repairing tissues than higher levels of light. The so-called Arndt-Schulz curve is frequently used to describe this biphasic dose response. This review will cover the molecular and cellular mechanisms in LLLT, and describe some of our recent results in vitro and in vivo that provide scientific explanations for this biphasic dose response.
The Use of Low-Level Energy Laser Radiation in Basic and Clinical Research. [2019]Laser radiation has specific attributes: monochromaticity, high coherence and polarization. These properties result in the extensive use of lasers in medicine. Laser devices can be assigned into three basic groups by means of their level of energy: high, medium and low energy. All of these types of radiation are used in medicine. However, the most commonly used, in basic science and clinical studies, is low-energy radiation. Molecular effects of low energy laser irradiation on cells are generally described as "fotobiostimulation" and "fotobiomodulation". These phenomena consequently lead to attempts to exploit this kind of radiation as a treatment method (low-level laser therapy-LLLT). Areas in which LLLT is used are: regenerative medicine (for healing wounds and ulcers); aesthetic medicine (to improve appearance of scars); dentistry (to accelerate healing of implants); physiotherapy (to reduce chronic pain syndromes), orthopedics (in bone healing) and cardiology (as a prevention of restenosis after percutaneous coronary intervention). This paper discusses the medical applications of LLLT which are used in daily clinical practice as well as those used in basic science.
Auto-Administered Photobiomodulation on Diabetic Leg Ulcers Treatment: A New Way to Manage It? [2022]Peripheral arterial disease is a dramatic consequence of an uncontrolled diabetic condition causing an increase of morbidity and mortality and its treatment is currently medical or surgical, finally requiring, in the 7-20% of cases, major or minor amputation. Photobiomodulation therapy (PBM) is a laser treatment used in medicine, thanks to its ability to stimulate the wound healing, the acceleration of inflammatory process, and the modulation of pain. Recently, the self-administration of the treatment has been suggested for different purposes in medicine and dentistry with a great number of advantages and no side effects.