Background & Aims

Brazil currently ranks sixth position among the countries with the highest number of diabetics in the world, exceeding 15 million of individuals. Diabetic ulcers represent until 70% of non-traumatic lower limb amputations of Brazilians patients, resulting in great socioeconomic impact and significant losses in patient’s quality of life. Currently, there is no fully effective treatment available for diabetic painful neuropathy and ulcers in Brazil. Conventional treatments in public hospitals are usually long, restricted and very painful so it is mandatory the development of additional protocols. Photobiomodulation (PBM) arises as a low-cost and no side effects therapy, which presents positive effects in decreasing painful symptoms, favoring tissue repair, and promoting wound healing in diabetic patients. This study aimed to evaluate the effect of PBM on pain scores, quality of life and tissue remodeling of DP from the University Hospital of University of Sao Paulo (USP/ Brazil).

Methods

Sixteen diabetic patients filled pain screening and quality of life questionnaires and assessed exteroceptive pain sensitivity by Quantitative Sensory Test (QST). A skin biopsy (5 mm) was taken to perform fibroblast culture. Photobiomodulation therapy consisted of 660 nm red light, applied twice week for 7 weeks in affected distal member. Patients were reevaluated in the last day of protocol and 6 months after treatment. Digital photographs of wounds were performed at the 1st and 14th day of protocol, area (cm2) and rate of retraction were analyzed by Image J software. Results were analyzed using GraphPad prism, represented by mean±sem; p<0.05.

Results

Clinical evaluation demonstrated that 100% (n=16) of patients presented T2DM and were classified as foot risk. The most reported symptoms were burning (60%) and tingling (55%) with worsening at night (50%) in the lower distal limbs. Photobiomodulation therapy induced significative retraction of wounds (p=0.001), this result was maintained 6 months after the end of treatment in 75% of patients. Furthermore, the results demonstrated a reduction in pain intensity (p=0.05) and an improvement in pain impact (p=0.05) in quality of life. Also, it was a significantly reduction in anxiety symptoms (p=0.05). QST revealed that individuals had a significant improvement in mechanical perception after PBM therapy. In vitro evaluation, showed that PBM improved cell viability and migration, regulating matrix metalloproteinases production, very important in tissue remodeling response.

Conclusions

Photobiomodulation therapy was capable to improve pain scores and quality of life of patients, reinforcing the use of this adjuvant tool in the clinical treatment of painful symptoms and in the wound healing process in diabetic patients.

References

INTERNATIONAL DIABETES FEDERATION (IDF). Diabetes Atlas. 2021. Disponível em: https://diabetesatlas.org/atlas/tenth-edition/. Acesso em julho, 2022. ISBN: 978-2-930229-98-0

FEITOSA, M.C.P., CARVALHO, A. F. M., FEITOSA, V. C., et al. Effects of the Low-Level Laser Therapy (LLLT) in the process of healing diabetic foot ulcers. Acta Cir. Bras., vol.30, n.12, pp.852-857, 2015.

DA SILVA OLIVEIRA V.R., CURY, D.P, YAMASHITA, L.B, ESTECA, et al. Photobiomodulation induces antinociception, recovers structural aspects and regulates mitochondrial homeostasis in peripheral nerve of diabetic mice J. Biophotonics. 11(9): e201800110, 2018.

DE ALENCAR FONSECA SANTOS, J., et al. Effects of Low-Power Light Therapy on the Tissue Repair Process of Chronic Wounds in Diabetic Feet. Photomedicine and Laser Surgery, v.36, n. 6, 2018.

Presenting Author

Camila Dale

Poster Authors

Victoria da Silva Oliveira

Ms, phD

Institute of Biomedical Sciences of University of São Paulo - Brazil

Lead Author

E-mail

Inaeh de Paula Oliveira

Ms.

University of Sao Paulo - Brazil

Lead Author

E-mail

Heloísa Alonso Matielo

MSc.

Institute of Biomedical Sciences of University of São Paulo - Brazil

Lead Author

E-mail

Victhor Teixeira de Oliveira

Ms.

University of Sao Paulo - Brazil

Lead Author

E-mail

Jean Lucas Kremer

phD.

University of Sao Paulo - Brazil

Lead Author

E-mail

Milena Cristina Dias Casalverini

MD.

University Hospital of the University of São Paulo - Brazil

Lead Author

E-mail

Fernando Quadros Ribeiro

MD.

University Hospital of the University of São Paulo - Brazil

Lead Author

E-mail

Silvya Stuchi Maria-Engler

phD.

University of Sao Paulo - Brazil

Lead Author

E-mail

Manoel Teixeira

University of São Paulo School of Medicine

Lead Author

E-mail

José Pinhata Otoch

phD.

University of Sao Paulo - Brazil

Lead Author

E-mail

Camila Squarzoni Dale

Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo

Lead Author

E-mail

Topics

  • Models: Chronic Pain - Neuropathic