Seeing the Light: Dermatologists Weigh In on Light Therapy for Acne

Light therapy for acne treatment is gaining in popularity despite a lack of clinical evidence to back it up.¹ The American Academy of Dermatology acknowledged in its 2016 acne guidelines that light and laser therapy may be beneficial for some patients with acne, but that more studies are needed to determine the efficacy of such modalities.²

In a systematic review of 71 randomized trials (N=4211 patients; 66% women) examining light therapy, Barbaric and colleagues did not find sufficient evidence to recommend changes to existing practice.^3,4 The types of light therapy included nearly the entire spectrum: red, yellow, green, blue, blue-red, infrared, broad-spectrum light, intense pulsed light, methyl aminolevulinate-photodynamic therapy (MAL-PDT), pulsed-dye lasers, 1450-nm lasers, and blue light-emitting diodes (LED).⁴

Of the 71 studies, red light MAL-PDT demonstrated modest reductions in acne lesions.⁴ However, the researchers stopped short of any recommendations for light therapy to treat acne due to the heterogeneity in the study designs and data collection. While blue, red, and combination blue-red light therapy are approved by the US Food and Drug Administration (FDA) for acne treatment, MAL-PDT remains off-label.¹ Still, clinicians are eager to embrace the technology because light therapy is versatile for treating a broad range of dermatologic conditions and has few adverse effects.

Comparison of the light therapies was difficult due to the wide variation in the clinical trials, including severity of acne, type of light therapy, frequency of application, wavelength variation, concomitant use of topical agents, and inconsistent use of comparators.⁴ Furthermore, the trials tended to be small, averaging 31 participants and concentrated on patients in their 20s and 30s.⁴ Thus, it was not possible to derive one of the primary outcomes of the systematic review — the participants’ global assessment of improvement — because the studies did not use standard measurements.⁴

Researchers deemed severe adverse events, such as blistering and scarring, as critical to understanding the efficacy of light therapy in acne. Due to the lack of uniformity and safety data in the studies, many were rated as providing weak evidence.⁴ Also, few studies included cost effectiveness data in order to better gauge the efficacy of treatments.³

Safety and Convenience May Surpass Evidence

Despite the lack of robust evidence, dermatologists and their patients are embracing light therapy, either as monotherapy or as adjunctive therapy to synergize systemic or topical agents for acne.⁵ Although treatment effects can take weeks to become evident, patients may favor noninvasive treatments that can be administered during their lunch hour with few adverse effects. Emerging evidence has convinced clinicians that light therapy may benefit not only some aspects of acne, but also psoriasis, rosacea, actinic keratosis, wound healing, Bowen’s disease, and basal cell carcinoma.⁵  

In an interview with Dermatology Advisor, dermatologist Glynnis Ablon, MD, FAAD, associate professor at the University of California at Los Angeles, hopes that “clinicians would consider LED therapy as an adjunct [treatment] to all acne cases. It is noninvasive, painless, and provides proven results. We may write prescription medications, but adding LED phototherapy delivers faster results, [and] happier, and more compliant patients.”

With adequate eye protection, light therapy can produce safe results that minimize downtime for patients.⁵ Home versions of light devices are available, albeit in weaker strengths than medical devices, and are best suited for mild acne cases as an adjunct to topical therapy.⁵

“Home LED units are quite small,” said Dr Ablon, “so they are great for college students as an adjunct to their therapy or for extremely mild cases of acne where OTC [over-the-counter] products and LED may be all that is needed.”

Alternative to Systemic Agents

Treating women of childbearing age with severe acne is especially challenging because some of the most efficacious treatments, such as systemic retinoids, are also teratogenic.⁶ In a study of 100 women of childbearing age (21 to 30) with grades 3 and 4 facial acne with Fitzpatrick skin types IV to VI, Deshpande and colleagues found that intense pulsed light (IPL) monotherapy was effective in clearing acne lesions and was well tolerated.⁶

During the 6-week trial, patients received IPL treatments with a 530 nm to 1200 nm filter once per week. Physician assessment by a blinded evaluator at weeks 1 and 6 reported improvement in lesion count and erythema, and 80% of patients reported excellent improvement in their acne. Of the 93 patients who completed the trial, only 4 developed erythema. Immediate post-treatment effects included mild to moderate erythema and stinging, but no patient had lasting adverse effects.⁶  

“I have found IPL very effective, but there is no direct comparative evaluation against systemic retinoids,” explained lead investigator and dermatologist Ajay J. Deshpande, MBBS, DVD, DNB, of the Maharashtra Medical Foundation Joshi Hospital in Pune, India, in an interview with Dermatology Advisor. “IPL may become one of the top 3 approaches in the management of acne when systemic drugs are contraindicated.”

References

1. Alexiades M. Laser and light-based treatments of acne and acne scarring. Clin Dermatol. 2017;35(2):183-189.
2. Zaenglein AL, Pathy AL, Schlosser BJ, et al. Guidelines of care for the management of acne vulgaris. J Am Acad Dermatol. 2016;74(5):945-973.
3. Posadzki P, Car J. Light therapies for acne [published online March 14, 2018]. JAMA Dermatol. doi:10.1001/jamadermatol.2018.0110
4. Barbaric J, Abbott R, Posadzki P, et al. Light therapies for acne (review). Cochrane Database Syst Rev. 2016;9:CD007917.
5. Ablon G. Phototherapy with light emitting diodes: treating a broad range of medical and aesthetic conditions in dermatology. J Clin Aesthet Dermatol. 2018;11(2):21-27.
6. Deshpande AJ. Efficacy and safety evaluation of high-density intense pulsed light in the treatment of grades II and IV acne vulgaris as monotherapy in dark-skinned women of child bearing age. J Clin Aesthet Dermatol. 2018;11(4):43-48.