Adjusting the screen door: Developing a rational approach to assessing for thyroid disease in patients with alopecia areata

By Warren R. Heymann, MD
Jan. 11, 2018

Since my residency, I have been perplexed about how to screen patients with alopecia areata (or vitiligo) for thyroid disease. What tests should (or should not) be ordered? Which patients should be tested? When? I have not been alone in my state of confusion.

Honestly, I have not been consistent in screening for thyroid disease in patients with alopecia areata (AA), mostly because of conflicting published recommendations. My rabbi told me that the essence of his job is to “comfort the afflicted and afflict the comfortable.” This has been my general guide for ordering tests in this population — although I explain that there may be a small risk of thyroid disease, whether I have tested has essentially been based on the degree of concern of the patient or their parents. If there is ample worry (usually based on what has been Googled) that conversation ends with handing the patient a lab slip (checking a TSH, T4 and thyroid autoantibodies). Alternatively, if there is complete unawareness of any such association, because of the potential risk, perhaps testing is warranted. I have often deferred the decision to their primary physician.

Twenty-five years ago I published my first CME article about the cutaneous manifestations of thyroid disease. (1) Regarding the association of autoimmune thyroid disorders with AA, not too much has changed over the past quarter century. There have been innumerable reports of AA associated with Hashimoto thyroiditis, Graves disease, insulin-dependent diabetes, vitiligo, Addison disease, pernicious anemia, celiac disease, and atopic disorders. In a recent study of 78 patients with AA, including 46 (59%) men and 32 (41%) women, mean age 52.7 +/- 3.09 years, abnormal thyroid function and anti-thyroid autoantibodies were detected in 19 (24%) of patients. Of these, 12 (15%) patients were diagnosed with subclinical hypothyroidism, one (1%) with overt hypothyroidism, and four (5%) with euthyroid Hashimoto thyroiditis. The authors concluded that because of the significant association between AA and thyroid abnormalities, screening for thyroid function and anti-thyroid autoantibodies is advised in AA. (2)

The presence of thyroid peroxidase antibodies (TPO-Ab) is a marker for autoimmune thyroid disease, occurring in up to 10% of women of fertile age – often without overt thyroid disease – and substantially increases the risk for future thyroid dysfunction. In a study of 130 AA patients (45 male, 85 female), a TSH, free T4, and TPO-Ab were checked. Elevated TPO-Ab titers were found in 23 patients; 6.7 times greater in women. Twelve of these patients were already on thyroid hormone replacement therapy; the other 11 were considered at high risk for future thyroid dysfunction. The authors recommended that all patients with AA be checked annually for thyroid function parameters, including TPO-AB. (3)

Bin Saif et al performed a prospective case-control study of 50 Saudi alopecia totalis (AT) and alopecia universalis (AU) patients, 50 age- and gender-matched patients with localized AA, and 50 age- and gender- matched healthy subjects. Thyroid autoantibodies (TAAs) were positive in AT/AU (40%), mild AA (14%), and healthy subjects (4%). The frequency of TAAs was significantly higher in patients with AT/AU than in mild AA (p=0.001) and healthy controls (p less than 0.001). The author concluded that severe subtypes of AA are associated with a high risk of autoimmune thyroid disease, thereby recommending screening for thyroid abnormalities and TAAs in patients with AT/AU. (4)

Patel et al retrospectively reviewed 298 children with AA who had thyroid function screening (from a total 0f 751 AA patients over an 8 year period). Of those with thyroid screening, patterns of AA included patchy (68%), ophiasis (13%), totalis (9%), and universalis (10%). Severity was determined by percentage of hair loss on the scalp and was divided into mild (30.2%), moderate (32.9%), and severe (36.9%) types. A total of 59 (20%) patients had abnormalities on thyroid testing results. In this group of patients, hypothyroidism was the most frequent finding 29 (49%), with Hashimoto thyroiditis being the most common cause (24 [41%]). Other abnormalities included hyperthyroidism secondary to Grave disease (12 [20%]) and subclinical thyroid dysfunction (7 [12%]). Whereas age, duration of disease, pattern of alopecia, and diagnosis of autoimmune diseases had no significant association with abnormal thyroid findings, a personal history of Down syndrome (P = .004), atopy (P = .009), and family history of thyroid disease (P = .001) did. The authors recommended that routine thyroid function screening should be restricted to AA patients with a medical history of Down syndrome, personal history of atopy, a family history of thyroid disease, or clinical findings (goiter) suggestive of potential thyroid dysfunction in the individual patient. They suggest screening with a TSH and free T4 at the first presentation of these patients. If abnormalities are detected in either of these studies, subsequent testing for thyroid autoantibodies should be checked for potential autoimmune causes of thyroid dysfunction. (5)

AA usually presents in younger patients. In a retrospective study of 29 AA patients with an age of onset ≥ 50 years, 25 (86.2%) were female (female-to-male ratio, 6.2:1). There was a family history of alopecia areata in 17.2%, thyroid disease in 31%, atopic background in 6.9%, and 17/29 (58.6%) reported a significant stressful event. The most common disease pattern was patchy, and disease was mild in the majority of participants. Complete hair regrowth was observed in 82.8% of participants, and 37.9% relapsed. The authors concluded that late-onset alopecia areata is characterized by marked female predominance, less extensive disease, and a high incidence of complete hair regrowth. (6)

Will 2018 bring a change in how I screen for thyroid disease in patients with AA? Partially, based on the excellent work of Patel et al.

It helps to have targeted AA populations to screen, where the yield will be greater. Patel et al have defined those subgroups (Down syndrome, atopics, those with a family history of thyroid disease, or clinical signs or symptoms of thyroid disease) — a worthy accomplishment. Confirmation of their findings in children and adults would help strategize and streamline such screening. I would opt for checking a TSH, free T4, and thyroid autoantibodies at once, rather than having the patient have a second blood draw only if abnormalities are detected in a TSH or free T4. Statistically, if there are abnormalities, they are likely to be autoimmune in nature; if the antibodies are present, that person may be at a higher risk of developing autoimmune thyroid disease later in life, warranting further periodic screening. I see no need to repeat autoantibody titers if they are elevated.

More needs to be learned before definitive screening guidelines can be rendered. A long-term prospective study of alopecia areata patients would be very revealing (as it would also for patients with vitiligo). Regardless, Patel et al have offered data to set us on a more rational path.

1. Heymann WR. Cutaneous manifestations of thyroid disease. J Am Acad Dermatol 1992; 26: 885-902.
2. Lyakhovitsky A, et al. Increased prevalence of thyroid disorders in patients with new onset alopecia areata. Australas J Dermatol 2015; 56: 103-6.
3. Baars MP, et al. High prevalence of thyroid peroxidase antibodies in patients with alopecia areata. J Eur Acad Dermatol Venereol. 2013;27(1): e137-9.
4. Bin Saif GA. Severe subtype of alopecia areata is highly associated with thyroid autoimmunity. Saudi Med J 2016; 37: 665-61.
5. Patel D, et al. Screening guidelines for thyroid function in children with alopecia areata. JAMA Dermatol 2017; 153: 1307-10.
6. Lyakhovitsky A, et al. Late-onset alopecia areata: A retrospective cohort study. Dermatology 2017; Dec 7 [Epub ahead of print].

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