Aims: Vitiligo is an autoimmune skin disorder characterised by the loss of melanocytes, leading to development of depigmented lesions. Oxidative stress is believed to have a significant influence in the pathogenesis of vitiligo. Traditional treatment modalities yield variable outcomes and as such, systemic antioxidants have been proposed to play a potential role in vitiligo treatment in combination with more conventional therapies.
Methods: Human studies published until October 2022 with search terms "vitiligo," "antioxidants," “oxidative stress,” "treatment," and "therapy." were obtained from Embase, Ovid Medline and Cochrane databases. Papers were screened and extracted by three reviewers. The primary outcome of interest was clinical success rate and degree of regimentation achieved.
Results
Fifteen studies were identified (4 additional studies involving polypodium leucotomos are presented separately), including seven randomised controlled trials (RCTs) and 3 cohort studies. Four studies investigated the use of vitamin E, of which 2 were RCTs. Vitamin E increased the therapeutic success of NB-UVB significantly compared to NB-UVB alone, with 47% of patients obtaining >75% repigmentation vs 18%. Another trial investigated Vitamin E and NB-UVB compared to NB-UVB alone and demonstrated a repigmentation rate of 72.7% compared to 5.6%. A RCT evaluating the effectiveness of Gingko Biloba demonstrated a >75% repigmentation in 40% of patients group compared to just 9.1% in the control group. More novel systemic antioxidants such as Ginkgo Bilboba, Silybum Marianum, minocycline, Munzij and Mushil herbal preparations, turmeric, alpha-lipoic acid, aspirin, Coenzyme Q10 and coffee and sunflower seed preparations have also been used demonstrating variable effects on repigmentation.
Conclusion
There are limited standardised studies investigating the use of systemic antioxidants in the treatment of vitiligo, all with heterogenous study designs and outcomes. Vitamin E in particular has demonstrated significant efficacy in achieving regimentation. However, further studies are necessary to determine optimal antioxidant adjuvant therapy for vitiligo.