A recent study published in Skin Research and Technology revealed a potential causal relationship between vitiligo, a condition causing skin depigmentation, and two major autoimmune diseases namely rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE).
Researchers employed Mendelian randomization (MR) to investigate the connection between these conditions. The study, which analyzed data from genome-wide association studies, found a significant association between genetically predicted vitiligo and an increased risk of RA (OR 1.47, P <0.001) and SLE (OR 1.22 (95% CI, P 0.005). These associations were consistently supported by the various sensitivity analyses conducted. However, no causal relationship was found between vitiligo and other rheumatic diseases such as Sjögren’s syndrome and ankylosing spondylitis.
Vitiligo is frequently associated with various other autoimmune diseases, likely due to shared genetic and immunological factors. Studies have identified common genetic variants and loci, such as PTPN22 and the HLA region, which are shared between vitiligo and diseases like RA, type 1 diabetes, and autoimmune thyroid diseases. Genetic studies have also found links to RA and SLE, with shared variants in immune response regulation genes. Pathways involving interferon regulatory factors and cytokine genes, like those encoding TNF-α and interleukins, are implicated in these associations.
A retrospective study by Hadi et al. analyzed medical records of 1487 vitiligo patients in New York City over a 10-year period to investigate associated diseases and their variations across race/ethnicity and sex. The research revealed a statistically significant higher prevalence of several autoimmune conditions in vitiligo patients, with hypothyroidism being the most common, followed by rheumatoid arthritis. Notably, the study identified new associations with multiple sclerosis, idiopathic thrombocytopenic purpura, and lymphoma, while also confirming previously reported links to other autoimmune diseases.
This research marks a significant step forward in understanding the complex interplay between autoimmune conditions. The study findings necessitate the screening and monitoring of vitiligo patients for other autoimmune diseases, for adopting personalized treatment strategies and guiding future research into novel therapeutic targets.
References
- Zhao M, Zhang Y, Sun G. Identifying the genetic association between common rheumatic diseases and vitiligo. Skin Res Technol. 2024 Jul;30(7):e13846.
- Hadi A, Wang JF, Uppal P, Penn LA, Elbuluk N. Comorbid diseases of vitiligo: A 10-year cross-sectional retrospective study of an urban US population. J Am Acad Dermatol. 2020 Mar;82(3):628-633.