Severe subtype of alopecia areata is highly associated with thyroid autoimmunity

An Update on Alopecia and its Association With Thyroid Autoimmune Diseases

Alopecia is comorbid with several illnesses, including various autoimmune conditions such as thyroid disease. Leukocyte-mediated inflammation of hair follicles in alopecia was first described over a century ago. However, the high prevalence of the role of thyroid autoimmune disease in the pathogenesis of alopecia has only recently come to light, together with a strong association between the two. Therefore, this review focuses on articles published between 2011 and 2022 on alopecia's association with thyroid autoimmune disease, and the mechanism behind it. In addition, it highlights the link between alopecia and thyroid cancer, as patients with alopecia have increased risk of thyroid cancer. In conclusion, this comprehensive, focused, scoping review will serve as a reference highlighting recent information on alopecia, exploring its association with thyroid autoimmune diseases.

Comorbid Conditions Associated with Alopecia Areata: A Systematic Review and Meta-analysis

BACKGROUND

Alopecia areata (AA) is a complex autoimmune condition resulting in nonscarring hair loss. In recent years, many studies have provided new evidence on comorbid diseases present in patients with AA. However, some studies have conflicting results, and analyses conducting a comprehensive approach are lacking.

OBJECTIVE

The aim of our study was to provide an updated systematic review and meta-analysis of medical comorbidities associated with AA.

METHODS

We searched PubMed, Embase, and Web of Science for case-control, cross-sectional, and cohort studies investigating medical comorbidities in AA published from inception through 1 February 2023.

RESULTS

We screened 3428 abstracts and titles and reviewed 345 full text articles for eligibility. Ultimately, 102 studies were analyzed, comprising 680,823 patients with AA and 72,011,041 healthy controls. Almost all included studies (100 of 102 studies) were of satisfactory to high quality (Newcastle-Ottawa scale score ≥ 4). Among patients with AA, comorbidities with the highest odds ratios (OR) compared with healthy controls and data available from more than one study included vitamin D deficiency (OR 10.13, 95% CI 4.24-24.20), systemic lupus erythematous (OR 5.53, 95% CI 3.31-9.23), vitiligo (OR 5.30, 95% CI 1.86-15.10), metabolic syndrome (OR 5.03, 95% CI 4.18-6.06), and Hashimoto's thyroiditis (OR 4.31, 95% CI 2.51-7.40). AA may be a protective factor for certain disorders, for which the AA group had lower odds compared with healthy controls, such as irritable bowel syndrome (OR 0.38, 95% CI 0.14-0.99) and colorectal cancer (OR 0.61, 95% CI 0.42-0.89).

CONCLUSION

These findings corroborate and contextualize the risks across comorbidities for patients with AA. Further work should be done to identify the underlying pathophysiology and understand appropriate screening criteria.

Autoimmune, Inflammatory, Atopic, Thyroid, and Psychiatric Outcomes of Offspring Born to Mothers With Alopecia Areata

Importance

Alopecia areata (AA) is associated with diverse autoimmune and psychiatric disorders. However, an investigation on the long-term outcomes for offspring born to mothers diagnosed with AA is lacking.

Objective

To investigate the risks for autoimmune, inflammatory, atopic, thyroid, and psychiatric outcomes of offspring born to mothers with AA.

Design, Setting, and Participants

This retrospective population-based birth cohort study used the linked birth registration database with the Nationwide Health Insurance Service database of Korea. The participants included all newborns born to mothers with 3 or more visits with International Classification of Diseases, Tenth Revision code of L63 and 1:10 birth year, sex, insurance, income, and location of residence-matched control offspring born to mothers without AA during the years from 2003 to 2015. The analysis was conducted from July 2022 to January 2023.

Exposure

Maternal AA.

Main Outcomes and Measures

The occurrence of the following diseases was measured in newborns from birth to December 31, 2020: AA, alopecia totalis/universalis (AT/AU), vitiligo, psoriasis, inflammatory bowel disease, rheumatoid arthritis, atopic dermatitis, allergic rhinitis, asthma, hyperthyroidism, hypothyroidism, Graves disease, Hashimoto thyroiditis, attention-deficit hyperactivity disorder, mood disorder, and anxiety disorder. Multivariable Cox proportional hazard analyses were performed with the following covariates: birth year, age, insurance type, income level, location of residence, maternal age, mode of delivery, maternal history of atopic disorders, and autoimmune disorders.

Results

In total, 67 364 offspring born to 46 352 mothers with AA and 673 640 controls born to 454 085 unaffected mothers were analyzed. The risk of AA (adjusted hazard ratio [aHR], 2.08; 95% CI, 1.88-2.30), AT/AU (aHR, 1.57; 95% CI, 1.18-2.08), vitiligo (aHR, 1.47; 95% CI, 1.32-1.63), atopic disorders (aHR, 1.07; 95% CI, 1.06-1.09), hypothyroidism (aHR, 1.14; 95% CI, 1.03-1.25), and psychiatric disorders (aHR, 1.15; 95% CI, 1.11-1.20) was significantly increased in offspring born to mothers with AA. Among them, 5088 born to mothers with AT/AU were at much greater risk for the development of AT/AU (aHR, 2.98; 95% CI, 1.48-6.00) and psychiatric disorders (aHR, 1.27; 95% CI, 1.12-1.44).

Conclusions and Relevance

In this Korean retrospective population-based birth cohort study, maternal AA was associated with the development of autoimmune/inflammatory, atopic, thyroid, and psychiatric disorders in their offspring. Clinicians and parents need to be aware of the potential for these comorbidities to occur.

Review on Alopecia Areata in the Middle East and Africa: Landscape and Unmet Needs

BACKGROUND

Alopecia areata (AA) is an autoimmune disease characterized by non-scarring hair loss in adults and children. Clinical manifestations range from hair loss in small, well-circumscribed patches to total hair loss on the scalp or any other hair-bearing areas. Although the exact pathogenesis of AA is not fully understood, it is thought that loss of immune privilege caused by immunological dysregulation of the hair follicle is key. Genetic susceptibility also plays a role. Response to currently available treatments is widely variable, causing patient dissatisfaction and creating an unmet need. AA is frequently associated with multiple comorbidities, further affecting patient quality of life.

AIMS AND FINDINGS

AA causes a significant burden on dermatologists and healthcare systems in the Middle East and Africa. There is a lack of data registries, local consensus, and treatment guidelines in the region. Limited public awareness, availability of treatments, and patient support need to be addressed to improve disease management in the region. A literature review was conducted to identify relevant publications and highlight regional data on prevalence rates, diagnosis, quality of life, treatment modalities, and unmet needs for AA in the Middle East and Africa.

Prevalence and Risk Factors Associated with the Occurrence of Autoimmune Diseases in Patients with Alopecia Areata

BACKGROUND

Increased rates of autoimmune diseases (ADs) have been reported in association with alopecia areata (AA); however, the risk factors for coexisting ADs in AA patients have been poorly investigated.

OBJECTIVE

To evaluate the prevalence and factors associated with AD comorbidities in patients with AA.

METHODS

This case-control study included patients diagnosed with AA between January 2000 and March 2020. Individuals with AA, both with and without concomitant ADs, were statistically compared. Variables significantly associated with coexisting ADs were identified using univariate and multivariate logistic regression analyses. Multinomial logistic regression analysis was performed to identify the specific risk factors for each concomitant AD.

RESULTS

Among the 615 patients with AA, comorbid ADs were found in 76 (12.4%). Autoimmune thyroid disease (AITD) exhibited the highest frequency (n = 42, 6.8%), followed by vitiligo (n = 15, 2.4%), and systemic lupus erythematosus (SLE) (n = 12, 2.0%). Logistic regression analyses revealed that female sex (odds ratio [OR] = 2.45, 95% confidence interval [CI] = 1.24-4.82; P = 0.011), nail abnormalities (OR = 2.49, 95% CI = 1.14-5.46; P = 0.023), and atopic diseases (OR = 1.98, 95% CI = 1.09-2.43; P < 0.001) were significantly associated with coexisting ADs. Regarding each concomitant AD, nail abnormalities were an associated factor for AITD (OR = 4.65, 95% CI = 1.96-7.24; P = 0.01), whereas coexisting atopic diseases were demonstrated as a predictor of vitiligo (OR = 2.48, 95% CI = 1.43-4.58; P = 0.02). Female sex (OR = 1.61, 95% CI = 1.18-4.27; P = 0.04) and family history of AD (OR = 1.85, 95% CI = 1.26-4.19; P = 0.03) were predictors of SLE.

CONCLUSION

This study suggests that female AA patients with nail abnormalities and atopic diseases have increased rates of AD comorbidities. A thorough review of systems for associated factors can help physicians screen for concomitant ADs.

Alopecia Universalis Occurring after Alemtuzumab Treatment for Multiple Sclerosis. A Two-Year Follow-Up of Two Patients

Alopecia Universalis (AU) is the most severe form of Alopecia Areata and is caused by cytotoxic T-cells reacting with follicular autoantigens, producing complete loss of scalp and body hair. Alemtuzumab is a highly efficacious monoclonal antibody used in the treatment of Multiple Sclerosis (MS), but it causes secondary autoimmunity in up to 40% of patients. Many factors are believed to contribute to this process, but pathogenic mechanisms are not well clear. To date, three cases of AU after treatment with Alemtuzumab have been reported. In this paper we report the cases of two patients who developed AU 12 months after the second cycle of Alemtuzumab, with a review of the literature. One year after the end of the second cycle, two female patients in their thirties experienced complete hair loss. The first case was temporally associated with a significant drop in vitamin D (VD) levels. The second case was accompanied by joint swelling. Both patients had thyroid alterations and showed no hair regrowth after a 2-year follow-up. AU must be considered among the secondary autoimmune manifestations of Alemtuzumab treatment. We emphasize the need for appropriate patient screening and thorough clinical surveillance for factors predisposing patients to secondary autoimmunity.

Increased Incidence of Thyroid Disease in Patients with Alopecia Areata: A Systematic Review and Meta-Analysis

Background: Alopecia areata (AA) is a common, clinically heterogeneous, immune-mediated, nonscarring hair loss disease with a pathogenesis that is not fully understood. The prevalence of thyroid disease is likely increased among individuals with AA. However, this association remains controversial. Objective: To evaluate the risk of thyroid disease in patients with AA. Methods: We performed a systematic review by searching both English and Chinese literature databases. Random- or fixed-effects models were used to summarize the association between thyroid disease and AA. Results: In total, 17 articles were included in this meta-analysis, with 2,850 AA cases and 4,667 controls. Overall, the prevalence of thyroid disease in patients with AA was significantly increased compared with that in controls (odds ratios 3.66, 95% confidence intervals 2.90–4.61). Conclusions: The results suggest that AA patients should be screened for thyroid disease.

Vitamin D supplementation for the prevention or depletion of side effects of therapy with alemtuzumab in multiple sclerosis

PURPOSE OF REVIEW

Not only the multiple sclerosis specialist but also the general neurologist and primary care practitioner are increasingly aware of possible adverse events (AEs) by treatment with alemtuzumab (over 47% risk of secondary autoimmune-mediated diseases). Vitamin D supplementation's effect (VDS) to reduce these autoimmune AEs is poorly performed in routine practice. This article seeks to justify why this simple, inexpensive, patient-friendly therapy should be seriously discussed.

RECENT FINDINGS

Patients who have developed autoimmunity also show a high basal level of IL-21, a cytokine which increases the growth of auto-reactive T-cells. For side effects such as thyroid dysfunction, autoimmune thrombocytopenia, autoimmune hemolytic anemia, autoimmune hepatitis, diabetes mellitus type 1, and alopecia areata/alopecia totalis, VDS may have an impact on the immunological mechanism, in particular lowering levels of IL-17 and IL-21.

SUMMARY

The potential role of vitamin D in influencing autoimmune diseases is evident. If a life-threatening side-effect can be prevented by high-dose VDS, it is ethical to initiate this add-on therapy despite contradictory results in studies on the effectiveness of VDS.

Thyroid diseases and skin autoimmunity

The skin is the largest organ of the body, at the boundary with the outside environment. Primarily, it provides a physical and chemical barrier against external insults, but it can act also as immune organ because it contains a whole host of immune-competent cells of both the innate and the adaptive immune systems, which cooperate in eliminating invading pathogens following tissue injury. On the other hand, improper skin immune responses lead to autoimmune skin diseases (AISD), such as pemphigus, bullous pemphigoid, vitiligo, and alopecia. Although the interplay among genetic, epigenetic, and environmental factors has been shown to play a major role in AISD etiology and progression, the molecular mechanisms underlying disease development are far from being fully elucidated. In this context, epidemiological studies aimed at defining the association of different AISD with other autoimmune pathologies revealed possible shared molecular mechanism(s) responsible for disease progression. In particular, over the last decades, a number of reports have highlighted a significant association between thyroid diseases (TD), mainly autoimmune ones (AITD), and AISD. Here, we will recapitulate the epidemiology, clinical manifestations, and pathogenesis of the main AISD, and we will summarize the epidemiological evidence showing the associations with TD as well as possible molecular mechanism(s) underlying TD and AISD pathological manifestations.

Alopecia areata and overt thyroid diseases: A nationwide population-based study

An association between alopecia areata (AA) and other autoimmune diseases has been reported. We investigated the associations between AA and overt autoimmune thyroid diseases. A nationwide, population-based, cross-sectional study was performed using the Korea National Health Insurance claims database. We defined patients with AA as those whose records showed at least four physician contacts in which AA, alopecia totalis (AT) or alopecia universalis (AU) was the principal diagnosis. We also established an age- and sex-matched control group without AA. In a subgroup analysis, patients with AT or AU were classified into the severe AA group, and the remainder were classified into the mild to moderate AA group. Patients with AA were at an increased risk of Graves' disease (odds ratio [OR], 1.415; 95% confidence interval [CI], 1.317-1.520) and Hashimoto thyroiditis (OR, 1.157; 95% CI, 1.081-1.237), and the associations were stronger in the severe AA group (Graves' disease: OR, 1.714; 95% CI, 1.387-2.118; Hashimoto thyroiditis: OR, 1.398; 95% CI, 1.137-1.719). In conclusion, AA was significantly associated with overt autoimmune thyroid diseases. Furthermore, the risk was much higher in the severe AA group.

Alopecia Universalis following Alemtuzumab Treatment in Multiple Sclerosis: A Barely Recognized Manifestation of Secondary Autoimmunity-Report of a Case and Review of the Literature

Secondary autoimmunity is the most frequent adverse event occurring in almost every other alemtuzumab-treated multiple sclerosis patient. We report a case of a patient with relapsing-remitting multiple sclerosis who reported smooth, circular areas of complete hair loss on both thighs 6 months after the second treatment cycle with alemtuzumab. The patient was diagnosed as having alopecia areata (AA). Within 3 months, AA progressed to complete loss of all body hair (alopecia universalis). Current literature rarely connects alemtuzumab with the onset of alopecia of autoimmune origin. Here, we report a little-noticed autoimmune disease affecting the skin, very likely being associated with alemtuzumab. We emphasize the necessity of careful clinical surveillance of alemtuzumab-treated patients for yet undescribed autoimmune diseases.