|LETTER TO THE EDITOR
|Ahead of print publication
Is screening for thyroid dysfunction a requisite for all with alopecia areata?
Rahman Nadiya1, Priya Prathap2, Neelakhandan Asokan2
1 Department of Dermatology, Venereology and Leprosy, Daya Hospital, Thrissur, Kerala, India
2 Department of Dermatology, Venereology and Leprology, Government Medical College, Thrissur, Kerala, India
|Date of Submission||03-Feb-2022|
|Date of Acceptance||05-Feb-2022|
|Date of Web Publication||15-Apr-2022|
Gitanjali, Kadavil Lane, Chembukkavu, Thrissur - 680 020, Kerala
Source of Support: None, Conflict of Interest: None
|How to cite this URL:|
Nadiya R, Prathap P, Asokan N. Is screening for thyroid dysfunction a requisite for all with alopecia areata?. Thyroid Res Pract [Epub ahead of print] [cited 2022 May 24]. Available from: https://www.thetrp.net/preprintarticle.asp?id=343325
Alopecia areata (AA) is a nonscarring, chronic inflammatory disease characterized by circumscribed areas of hair loss with no surface changes with a lifetime risk of 1.7%. The prevalence of thyroid disorders in AA varies from 8% to 28%.
We conducted a comparative cross-sectional study to determine the association of AA with thyroid disease and the proportion of autoimmune thyroid disease in those with thyroid dysfunction. The sample size was calculated based on the study by Thomas and Kadyan in which the prevalence of thyroid disorders was 18.3% (P = 0.01; odds ratio [OR] = 3.75). Sixty-six patients with AA diagnosed by a faculty with postgraduate degree in dermatology and 132 age- and gender-matched controls without AA who presented with skin infections were chosen after obtaining consent. Ethical clearance was acquired from the institutional research committee. All patients underwent thyroid function testing. Those with abnormal thyroid function were tested for antithyroid peroxidase (TPO) antibodies and antithyroglobulin (TG) antibodies.
The baseline demographic characteristics of cases and controls are described in [Table 1].
Thyroid dysfunction was more in AA patients (8/66; 12.1%) compared to controls (6/132; 4.5%), but statistical significance was not present (P = 0.051; OR = 2.897, confidence interval [CI] = 0.961–8.730). Among AA cases, hypothyroidism was the most frequently associated thyroid dysfunction (n = 6). Subclinical hypothyroidism and overt hyperthyroidism were detected in one patient each.
The baseline demographic variables and clinical characteristics of patients with AA with thyroid disease and those without thyroid disease are depicted in [Table 2].
|Table 2: Baseline demographic variables and clinical characteristics of patients with alopecia areata with thyroid disease and those without thyroid disease|
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Thyroid disease was identified to be more in those above 40 years of age among AA patients in our study (P = 0.029; OR = 9, CI = 1.559–51.949). Chu et al. (OR = 2.52) and Park et al. (OR = 7.89, CI = 4.94–12.62) also demonstrated a stronger association of thyroid disease with AA in older age groups.,
We did not detect any relationship of thyroid disease with gender, relapses, family history of AA, the pattern of AA, and severe AA (P = 0.03; OR = 0.136, CI = 0.023–0.789). However, Thomas and Kadyan and Park et al. (P < 0.001; OR = 3.23, CI = 2.13–4.90) observed noteworthy association between thyroid dysfunction and severe AA., The reason for the contrary finding in our study might be the smaller sample size.
Functional defect in regulatory T cells which play a key role in autoimmune diseases and HLA association (HLA-DQB1 * 03) were proposed as factors linking AA and thyroid disease.
In our study, autoimmune thyroid disease was more in AA patients compared to controls. However, this was not statistically significant (P = 0.156; OR = 6.00, CI = 0.582–61.842). According to our study, the presence of thyroid autoantibodies did not necessarily indicate the presence of severe types of AA. Two of the three patients with alopecia totalis had thyroid dysfunction, but only one had antithyroid antibodies (both anti-TPO and anti-TG). More patients with patchy AA (n = 5) had antithyroid antibodies compared to severe AA. Wang et al. did a case–control study, measuring antithyroid antibodies among all study subjects. They also inferred similarly. However, Bin Saif and Park et al. noted a higher frequency of antithyroid antibodies in patients with alopecia totalis and universalis than in mild AA (P < 0.001)., Systematic review and meta-analysis by Kinoshita-Ise et al. and Lee et al. recommended that AA patients need not be routinely screened for autoimmune thyroid disease except in severe and refractory AA.,
Patel et al. suggested screening guideline for Thyroid function test (TFT) among children with AA whereby health-care cost could be reduced and unnecessary testing could be avoided. TFT may be done only when there is history of atopy, family history of thyroid disease, or clinical findings indicative of possible thyroid dysfunction.
We would like to highlight that despite adjusting for age, the association of AA with thyroid disease was found to increase past middle age (P = 0.029; OR = 9). Hence, all patients who have a late onset of AA would benefit from screening for thyroid disease, irrespective of the severity of their disease. Although thyroid dysfunction and autoimmune thyroid disease were more frequent among AA patients compared to controls, we did not obtain statistical significance. Therefore, TFT and autoimmune thyroid screening are indicated among AA patients only if there are clinical features of goiter, hypothyroidism, or hyperthyroidism.
A limitation of our study was that autoantibody screening was done only for those patients with abnormal TFT due to financial constraints. However, this will not affect patient care as treatment for thyroid diseases relies on abnormal thyroid function test than the presence of autoantibodies. Comparative cross-sectional design was the strength of our study.
A systematic review and meta-analysis with multivariate analysis design and long-term follow-up studies could enable to formulate thyroid screening guidelines among AA patients.
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Conflicts of interes
There are no conflicts of interest.
| References|| |
Naik PP, Farrukh SN. Association between alopecia areata and thyroid dysfunction. Postgrad Med 2021;133:895-8.
Thomas EA, Kadyan RS. Alopecia areata and autoimmunity: A clinical study. Indian J Dermatol 2008;53:70-4.
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Chu SY, Chen YJ, Tseng WC, Lin MW, Chen TJ, Hwang CY, et al.
Comorbidity profiles among patients with alopecia areata: The importance of onset age, a nationwide population-based study. J Am Acad Dermatol 2011;65:949-56.
Park SM, Oh YJ, Lew BL, Sim WY. The association among thyroid dysfunction, thyroid autoimmunity, and clinical features of alopecia areata: A retrospective study. J Am Acad Dermatol 2019;81:602-5.
Wang H, Gan H, Mei L, Yang G, Fang F. The association between alopecia areata and thyroid autoimmunity in Chinese adult patients: A controlled study. Biomed Res 2017;28:3517-21.
Bin Saif GA. Severe subtype of alopecia areata is highly associated with thyroid autoimmunity. Saudi Med J 2016;37:656-61.
Kinoshita-Ise M, Martinez-Cabriales SA, Alhusayen R. Chronological association between alopecia areata and autoimmune thyroid diseases: A systematic review and meta-analysis. J Dermatol 2019;46:702-9.
Lee S, Lee YB, Kim BJ, Lee WS. Screening of thyroid function and autoantibodies in patients with alopecia areata: A systematic review and meta-analysis. J Am Acad Dermatol 2019;80:1410-3.e4.
Patel D, Li P, Bauer AJ, Castelo-Soccio L. Screening Guidelines for Thyroid Function in Children With Alopecia Areata. JAMA Dermatol 2017;153:1307-10.
[Table 1], [Table 2]