Vitiligo is associated with a host of comorbid autoimmune, ocular and auditory, and dermatologic disorders.¹ Thyroid disease is the most prevalent of all autoimmune disorders among patients with vitiligo.² Age, sex, and race affect the presence of other autoimmune comorbidities including alopecia areata, diabetes mellitus, pernicious anemia, systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), Addison’s disease, inflammatory bowel disease (IBD), Sjögren’s syndrome, multiple sclerosis, and idiopathic thrombocytopenic purpura.^{1, 3} 

Autoimmune disorders 

A 10-year retrospective study found that 23% of patients with vitiligo had one or more of the following autoimmune disorders: thyroid disease, RA, alopecia areata, IBD, SLE, diabetes mellitus, and psoriasis.⁴ Sex and age influence the prevalence of comorbidities, with Grave’s disease, Hashimoto’s thyroiditis, atopic dermatitis, RA, SLE, and Sjögren’s syndrome more likely in female patients with vitiligo and psoriasis more likely in male patients. SLE and Sjögren’s syndrome are more common among elderly patients with vitiligo and myasthenia gravis is more common among younger patients.⁵ Race also affects the types of autoimmune comorbidities present. White patients demonstrated the highest rates of comorbidities, with hypothyroidism most frequently found in White and Hispanic/Latino patients. In contrast, psoriasis was most frequent in Asian patients, and SLE and RA were most frequent in Black patients.⁴ 

Thyroid disease 

Of all autoimmune disorders, the connection between thyroid disease (especially hypothyroidism and Grave’s disease)^{6, 7} and vitiligo is most established. Autoimmune thyroid disease (AITD) occurs in a range between 1.61% to 37% of patients with vitiligo compared to only 1% in the general population,⁸ and patients with vitiligo have a 2.5-times higher risk of developing AITD than those without vitiligo.⁹ In fact, AITD may have an increased prevalence (6-15%) even among first-degree relatives of patients with vitiligo.10 Vitiligo duration positively correlates with the risk of AITD and larger (>9%) body surface area involvement.¹¹ 

Ocular and audiological abnormalities 

Vitiligo relates to ocular abnormalities as there are melanocytes located in the uveal tract and retinal pigment epithelium (RPE).¹² In a study of 150 patients with vitiligo, 16% have ocular abnormalities in the uvea and RPE compared to 5% of controls.¹ 18.4% of patients with vitiligo demonstrated signs of normal tension glaucoma, compared with 0% of controls. Similar to the relationship between vitiligo and ocular abnormalities, audiological abnormalities are also being investigated as there are melanocytes located in the inner ear (scala vestibuli).¹³ 68.8% of patients with vitiligo had sensorineural hearing loss (SNHL) compared to 6.3% of controls in a study with 16 patients with vitiligo and 16 healthy controls.¹⁴ 

Psoriasis and atopic dermatitis 

Furthermore, psoriasis and atopic dermatitis are dermatologic disorders associated with vitiligo, with the latter showing significantly higher prevalence among pediatric patients and patients with early-onset vitiligo.¹⁵ There is a strong link between atopic dermatitis and vitiligo, with a systematic review of 16 studies illustrating a much higher frequency of atopic dermatitis among patients with vitiligo in contrast to controls.¹⁵ 

The future of vitiligo comorbidities research 

It is critical that care providers remain conscious of these comorbidities in vitiligo, especially autoimmune thyroid disorders. To improve quality of life for patients with vitiligo, future studies should focus on further elucidating the significance of these associations. 

References 

1. Dahir AM, Thomsen SF. Comorbidities in vitiligo: comprehensive review. Int J Dermatol. 2018;57(10):1157-1164. doi:10.1111/ijd.14055 
2. Gill L, Zarbo A, Isedeh P, Jacobsen G, Lim HW, Hamzavi I. Comorbid autoimmune diseases in patients with vitiligo: A cross-sectional study. J Am Acad Dermatol. 2016;74(2):295-302. doi:10.1016/j.jaad.2015.08.063 
3. 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;82(3):628-633. doi:10.1016/j.jaad.2019.07.036 
4. Sheth VM, Guo Y, Qureshi AA. Comorbidities associated with vitiligo: a ten-year retrospective study. Dermatology. 2013;227(4):311-315. doi:10.1159/000354607 
5. Chen YT, Chen YJ, Hwang CY, et al. Comorbidity profiles in association with vitiligo: a nationwide population-based study in Taiwan. J Eur Acad Dermatol Venereol. 2015;29(7):1362-1369. doi:10.1111/jdv.12870 
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7. Bae JM, Lee JH, Yun JS, Han B, Han TY. Vitiligo and overt thyroid diseases: A nationwide population-based study in Korea. J Am Acad Dermatol. 2017;76(5):871-878. doi:10.1016/j.jaad.2016.12.034 
8. Lotti T, D'Erme AM. Vitiligo as a systemic disease. Clin Dermatol. 2014;32(3):430-434. doi:10.1016/j.clindermatol.2013.11.011 
9. Vrijman C, Kroon MW, Limpens J, et al. The prevalence of thyroid disease in patients with vitiligo: a systematic review. Br J Dermatol. 2012;167(6):1224-1235. doi:10.1111/j.1365-2133.2012.11198.x 
10. Spritz RA. Shared genetic relationships underlying generalized vitiligo and autoimmune thyroid disease. Thyroid. 2010;20(7):745-754. doi:10.1089/thy.2010.1643 
11. Gey A, Diallo A, Seneschal J, et al. Autoimmune thyroid disease in vitiligo: multivariate analysis indicates intricate pathomechanisms. Br J Dermatol. 2013;168(4):756-761. doi:10.1111/bjd.12166 
12. Biswas G, Barbhuiya JN, Biswas MC, Islam MN, Dutta S. Clinical pattern of ocular manifestations in vitiligo. J Indian Med Assoc. 2003;101(8):478-480. 
13. Anbar TS, El-Badry MM, McGrath JA, Abdel-Azim ES. Most individuals with either segmental or non-segmental vitiligo display evidence of bilateral cochlear dysfunction. Br J Dermatol. 2015;172(2):406-411. doi:10.1111/bjd.13276 
14. Fleissig E, Gross M, Ophir I, Elidan J, Bdolah-Abram T, Ingber A. Risk of sensorineural hearing loss in patients with vitiligo. Audiol Neurootol. 2013;18(4):240-246. doi:10.1159/000350337 
15. Mohan GC, Silverberg JI. Association of vitiligo and alopecia areata with atopic dermatitis: a systematic review and meta-analysis. JAMA Dermatol. 2015;151(5):522-528. doi:10.1001/jamadermatol.2014.3324