Acne vulgaris and light-based therapies

Visible Light in the Treatment of Acne Vulgaris

Acne vulgaris, a prevalent dermatological disorder, frequently affects individuals' self-perception and general psychosocial functioning. The growing demand for home-based light therapy devices prompted a systematic review to assess the efficacy of visible light in acne treatment. Overall, 35 studies were included, representing 1185 cases of acne vulgaris (mean age: 23.7 years; sex: 63% female). A total of 69% of the included studies were level 2 evidence. Overall, 92% of patients achieved partial remission of their acne lesions using visible light therapy. Among the patients who experienced a partial remission of their acne, 46% experienced a reduction of 0% to 50% in their acne lesions, while 33% and 12% experienced reductions of 51% to 74% and 75% to 99%, respectively. Notably, blue light emerged as the predominant treatment modality in this context, used in around 64% of the cases. A total of 95% of the patients who were treated with blue light experienced a partial clearance of acne lesions; 44% experienced a reduction of 0% to 50% in their acne lesions, while 42% and 9% experienced reductions of 51% to 74% and 75% to 99%, respectively. Overall, the average total lesion count improved by 43% at week 4 compared to the baseline. The average number of treatment sessions was 22 (range 1-112 sessions). On average, treated patients responded within a period of 4 weeks. Commonly reported side effects included skin irritation and erythema. This review highlights the potential of visible light therapy in acne treatment. Head-to-head studies are needed to compare the efficacy of visible light compared to existing therapies for the treatment of acne.

Long-term exposure to low levels of ambient UVB are associated with a decreased risk of moderate-to-severe acne: A retrospective cohort study in college students

BACKGROUND

As a crucial component of solar radiation, the association between exposure to ambient ultraviolet (UV) radiation and acne remains unclear.

METHODS

This was a multicenter retrospective cohort study of incoming college students in five universities of China. Previous exposure (6 years prior to enrollment) to different wavelengths of ambient UVs were obtained from public repositories by linking to individual hometown addresses. Logistic models were applied to assess the relationship between ambient UV exposure and acne. Subgroup analysis was conducted by sun protection behaviors and time of daily sun exposure. Overall effect and single effect of exposure to four different wavelengths of UVs (305, 310, 324, and 380 nm) were estimated by Bayesian kernel machine regression (BKMR).

RESULTS

A total of 19,939 participants was included for analysis. Analysis in all participants showed a significant association between log-transformation levels of exposure to UV at 305 nm (log (UV 305 nm)) and acne (OR = 0.77, p = .021). The effect size was stronger in participants reporting no sun protection habit. Both UVs at 305 nm (OR = 0.51, p = .001) and 310 nm (OR = 0.50, p = .012) were associated a decreased risk of acne in participants reporting no sun protection habit. This inverse association was also observed in those exposed to low levels of UV (<1 h/day). The BKMR indicated consistent results that low levels of exposure to UVs combination and UVs at 305 and 310 nm were associated with a lower risk of acne.

CONCLUSION

Long-term exposure to relatively low levels of ambient UVB are associated with a decreased risk of moderate-to-severe acne in college students.

Indoor tanning: Evidence surrounding advertised health claims

Indoor tanning continues to remain common, despite evidence of an increased risk of skin cancer from artificial ultraviolet (UV) radiation. In the hopes of gaining customers, the tanning bed industry has marketed health benefits of indoor tanning such as increased vitamin D production, development of a base tan, enhanced mood, and treatment of certain dermatologic conditions. To better educate their patients, providers need a comprehensive reference reviewing the evidence that support or oppose these claims. In this work, we conducted an evidence-based review of the literature to identify and grade studies that investigate health claims related to UV exposure. Results indicate that there is little evidence to support each of these proposed health benefits. Tanning beds emit primarily UVA radiation, which is relatively ineffective at activating vitamin D or mood enhancing pathways, and the effects are minimal in regard to tanning beds generating a protective base tan or treating dermatologic conditions compared with the increased risk of skin cancer. Health care providers must continue to warn and educate patients about the misleading information propagated by the tanning bed industry as well as about the dangers of artificial UV radiation.

577-nm high-power optically pumped semiconductor laser is safe and effective in the treatment of inflammatory acne: a prospective, single-center, split-face comparative study

Objective

This study aimed to appraise the efficacy of a 577-nm high-power optically pumped semiconductor laser (HOPSL) for the treatment of inflammatory acne.

Methods

The study included 50 patients with acne vulgaris (inflammatory type), 14 men, and 36 women; patient ages ranged from 16 to 35 years. The left side of the face was treated with a single pass of a 577-nm high-power optically pumped semiconductor laser (HOPSL) every 2 weeks for 3 sessions. The severity of acne examined prior to the first session and 4 weeks after the last session (Investigator's Global Assessment of acne severity, IGA; single lesion count).

Results

At baseline, no statistically significant difference in the severity of inflammatory acne lesions between both sides was observed. One month after the final session, a significant improvement (IGA reduction of > 50%) of the overall severity of acne was observed in 49 patients (98%) on the laser-treated side versus 41 (82%) the control side of the face (P < .05). Hence, we found a significant reduction in the mean percentage of inflammatory papules, pustules, and nodules on the laser-treated versus the control side (79.33 vs 56.92, 78.04 vs 43.33, 64.85 vs 21.93%, respectively) (P < 0.05). Side effects in the form of erythema and irritation during sessions were transient and tolerated by the patients.

Conclusion

The 577-nm high-power optically pumped semiconductor laser is effective and safe for the treatment of inflammatory lesions (papules, pustules, and nodules) in acne patients.

Efficacy and safety of intense pulsed light using a dual-band filter for the treatment of facial acne vulgaris

Intense pulsed light (IPL) devices have been used in acne treatment in combination with conventional topical and oral medications. This study aimed to evaluate the efficacy and safety of IPL treatment using a dual-band filter (400-600 nm and 800-1200 nm) in facial acne vulgaris treatment. Twenty-three acne vulgaris patients were enrolled in this study. The patients were treated on both sides of the face. The treatments were performed in 2-week intervals for a total of five sessions. The final visit for the clinical evaluation was 2 weeks after the fifth treatment session. The mean number of papules, pustules, and comedones, and the melanin index, was significantly decreased at the final visit. However, sebum production and the erythema index showed no statistically significant differences after treatment. IPL treatment using a dual-band filter can be an alternative for patients who are unfit for systemic acne medication. It can also be used with conventional acne treatment for better treatment results.

Photothermal therapy using gold nanoparticles for acne in Asian patients: A preliminary study

Acne is a common skin disease that occurs in pilosebaceous units and is often prevalent in adolescence. There are many acne treatments, but they are associated with side effects, such as antibiotic resistance, teratogenicity, and irritation. Therefore, it is necessary to develop a more effective and safe alternative treatment for managing acne in patients of all ages. This study aimed to confirm the effect of gold photothermal therapy for acne. About 12 patients who visited the dermatologic clinic with moderate to severe acne vulgaris were included in the study, regardless of age or sex. All patients received three successive treatments at 1- to 2-week intervals with a photopneumatic device after applying the contents of a gold nanoparticle ample to the skin. Changes in the number of papules, pustules, and comedones before and after treatment, along with the overall improvement, were assessed. In four patients, a biopsy was taken before and 1 month after the last treatment. Significant reductions in acne lesions were observed after the use of gold photothermal therapy (papules, P = .001; pustules, P < .001; and comedones, P = .001). As noted in the Physician Global Assessment, the patients showed an average improvement of more than 50% in their condition. In the histopathological findings, a decrease in inflammatory cell infiltration and fibrotic changes of the dermis were observed after gold photothermal therapy. Gold photothermal therapy showed significant clinical and histological improvements in acne vulgaris in Asians without serious adverse effects.

Acne treatment efficacy of intense pulsed light photodynamic therapy with topical licochalcone A, l-carnitine, and decanediol: A spilt-face, double-blind, randomized controlled trial

BACKGROUND

Depending on disease severity, standard acne treatments can vary from topical to systemic therapy. However, poor compliance caused by adverse events and antibiotic resistance is a major cause of treatment failure.

AIMS

To determine the effectiveness of photodynamic therapy (PDT) with intense pulsed light (IPL) in the treatment of acne when combined with a cream containing licochalcone A, L-carnitine and decanediol (so-called, 'active formulation') versus PDT alone.

PATIENTS/METHODS

Twenty-nine volunteers, aged 21-39 years (26 women and 3 men, mean age 29.41 ± 5.24 years), with mild to severe facial acne, were enrolled. Each subject's face sides were randomized in a split-face manner to either receive PDT (IPL with a 400-720 nm cut-off filter, at 4 sessions with two-week intervals) combined with the active formulation cream twice daily for 10 weeks on one face side; or PDT and the vehicle cream on the other side, with the same treatment protocol. Reduction in acne quantity, melanin index and erythema index were assessed 2 weeks after the second treatment (day 28), 1 week after the fourth treatment (day 49), and 1 month after the fourth treatment (day 70).

RESULTS

Compared to baseline, patients in the active formulation group demonstrated a faster onset of reduction in the number of lesions at 2 weeks after the second treatment (p=0.010 for inflammatory acne and p=0.001 for non-inflammatory acne). A significantly greater reduction in lesion count was observed in the active formulation group compared with the vehicle group at all timepoints of evaluation for noninflammatory acne (day 28, day 49, and day 70; p=0.003, 0.005 and 0.002 respectively), and at 1 month after the fourth treatment for inflammatory acne (p=0.036). Compared to the vehicle group, the melanin index of the active formulation group decreased significantly at 1 month after the fourth treatment (p=0.015).

CONCLUSION

PDT is more effective in treating acne when combined with a topical cream containing licochalcone A, L-carnitine and decanediol, than PDT alone. Significant acne reduction and improvements in post-inflammatory hyperpigmentation were observed, which offers acne patients a better therapeutic option. It is a safe and effective combination treatment for patients with moderate and severe acne.

Emerging Therapies for Acne Vulgaris

As we gain a greater understanding of acne pathogenesis, both new agents as well as new uses for established drugs are being considered for the treatment of acne vulgaris. Multiple clinical trials assessing new formulations or combinations of established acne treatments have been conducted, and novel uses of antimicrobials such as modified diallyl disulfide oxide and nitric oxide are being assessed in clinical trials. There are also a multitude of new therapies currently being studied that target the inflammatory cascade of acne pathogenesis, including sebosuppressive and anti-inflammatory phytochemicals, and  small molecule inhibitors targeting sebaceous glands and enzymes, among others. Laser and light therapy is also being modified for the treatment of acne through combination methods with metal nanoshells and vacuum assistance. Probiotics have gained popularity in medicine as greater knowledge of the microbiome and its effects on multiple organ systems is being elucidated. Studies describing the positive effects of certain ammonia-oxidizing bacterial strains in the regulation of the skin's inflammatory response are ongoing. Therapies for acne are constantly evolving and current gold-standard acne therapy may be supplemented with novel treatment modalities in the near future.

Algorithm for acne treatment: Ibero-Latin American consensus

Acne is a chronic, immune-mediated, inflammatory disease with high prevalence among adolescents. By compromising face, thorax and back, with the risk of permanent scars, it has a negative impact on the quality of life. Effective, safe and early treatment is the key to remission, while decreasing the risk of physical and/or emotional sequelae. The Iberian-Latin American Group of Acne Studies joined professionals with expertise and developed a practical therapeutic algorithm, adapted to the reality of Latin American countries, Spain and Portugal. This article intends to disseminate it with an updated review on a rational, safe and effective acne treatment.