Alopecia areata and risk of common infections: a population-based cohort study.

BACKGROUND: It is not known whether alopecia areata (AA) is associated with a greater or reduced risk for infection. AIM: We undertook a population-based study exploring associations between AA and common infections. METHODS: We extracted primary care records from the UK Oxford-Royal College of General Practitioners Research and Surveillance Centre database (trial registration: NCT04239521). The incidence of common and viral infection composite outcomes, and individual respiratory, gastrointestinal (GI), skin, urinary tract, genital and herpes infections, were compared in people with AA (AA group, n = 10 391) and a propensity-matched control group (n = 41 564). Adjusted hazard ratios (aHRs), controlling for sociodemographic and clinical covariates, and comorbidities were used to estimate the association between AA and each infection over 5 years. RESULTS: The incidence (per 100 person-years) of common infections was slightly higher in the AA group [14.2, 95% confidence interval (CI) 13.8-14.6] than the control group (11.7, 95% CI 11.5-11.9). In adjusted analysis, positive associations were observed for composite outcomes (common infections aHR 1.13, 95% CI 1.09-1.17; viral infections aHR 1.11, 95% CI 1.07-1.16) and with respiratory tract, GI, skin and herpes simplex infections (aHR range 1.09-1.32). Excluding people in the control group without a recent consultation with their general practitioner showed no association between AA and infection (common infections aHR 1.01, 95% CI 0.98-1.05, viral infections aHR 0.99, 95% CI 0.95-1.03). CONCLUSIONS: The association between AA and common infection may represent a higher propensity of people with AA to engage with healthcare services (and thereby to have infections recorded), rather than a true association between AA and infection. Overall our findings suggest that AA is not associated with a clinically significantly increased or decreased incidence of common infections.

Alopecia areata and risk of atopic and autoimmune conditions: population-based cohort study.

BACKGROUND: Alopecia areata (AA) has features of both autoimmune and atopic pathogenesis, but information on the risk of people with AA developing autoimmune and atopic conditions is limited. OBJECTIVE: To assess the prevalence and incidence of atopic and autoimmune conditions in people with AA. METHODS: This was a population-based cohort study of 8051 adults with newly diagnosed AA (AA group) and 32 204 adults in the matched control group, using the UK Oxford-Royal College of General Practitioners (RCGP) Research and Surveillance Centre (RSC) network primary care database, 2009-2018 (trial registration number: NCT04239521). Baseline prevalence of common atopic and autoimmune conditions, and risk of new-onset atopic and autoimmune disease, were estimated. RESULTS: Atopic and autoimmune conditions were more prevalent in the AA group than the control group (atopic 37.2% vs. 26.7%, autoimmune 11.5% vs. 7.9%). The AA group were 43% more likely to develop any new-onset atopic condition [adjusted hazard ratio (aHR) 1.43. 95% confidence interval (CI) 1.28-1.61] and 45% more likely to develop any autoimmune condition (aHR 1.45, 95% CI 1.28-1.66) compared with the control group. When examining individual conditions, the AA group were at increased risk of atopic dermatitis (aHR 1.91, 95% CI 1.67-2.19), allergic rhinitis (aHR 1.32, 95% CI 1.14-1.54), autoimmune hypothyroidism (aHR 1.65, 95% CI 1.35-2.02), systemic lupus erythematosus (aHR 4.51, 95% CI 1.88-10.82) and vitiligo (aHR 2.39, 95% CI 1.49-3.82). There was no evidence for a higher incidence of other conditions examined. CONCLUSION: People with AA have an increased burden of atopic and autoimmune comorbidity. This supports previous work suggesting that both T helper cell (Th)1 and Th2 immune responses may be implicated in the pathogenesis of AA.

The associated burden of mental health conditions in alopecia areata: a population-based study in UK primary care.

BACKGROUND: Alopecia areata (AA) is a common cause of nonscarring hair loss that can have a profound psychological impact. OBJECTIVES: To assess the co-occurrence of depression and anxiety in adults with AA compared with the general population, and to evaluate the mental health treatment burden and impact on time off work and unemployment. METHODS: In total, 5435 people with newly diagnosed AA in UK primary care were identified from the Oxford Royal College of General Practitioners Research and Surveillance Centre network database, and matched to 21 740 controls. In cases and controls, we compared the prevalence and incidence of depressive episodes, recurrent depressive disorder and anxiety disorder, rates of time off work and unemployment, and, in those with pre-existing mental health conditions, rates of mental health-related prescribing and referral rates. This observational was registered with ClinicalTrials.gov (NCT04239521). RESULTS: Depression and anxiety were more prevalent in people diagnosed with AA than in controls (P < 0·001). People with AA were also more likely to subsequently develop new-onset depression and anxiety: adjusted hazard ratio (aHR) for recurrent depressive disorder 1·38 [95% confidence interval (CI) 1·13-1·69], depressive episodes aHR 1·30 (95% CI 1·04-1·62) and anxiety disorder aHR 1·33 (95% CI 1·09-1·63); to be issued time off work certificates (aHR 1·56, 95% CI 1·43-1·71); and to be recorded as unemployed (aHR 1·82, 95% CI 1·33-2·49). Higher rates of antidepressant prescribing were also seen in people with AA. CONCLUSIONS: People with AA have higher rates of depression and anxiety than those without AA. This impacts deleteriously on mental health treatment burden, time off work and unemployment. Evidence-based mental health treatment programmes are needed for people with AA.

Epidemiology, management and the associated burden of mental health illness, atopic and autoimmune conditions, and common infections in alopecia areata: protocol for an observational study series.

INTRODUCTION: Alopecia areata (AA) is a common cause of immune-mediated non-scarring hair loss. Links between AA and common mental health, autoimmune and atopic conditions, and common infections have previously been described but remain incompletely elucidated and contemporary descriptions of the epidemiology of AA in the UK are lacking. METHODS AND ANALYSIS: Retrospective study series using a large population-based cohort (5.2 million) from the Oxford Royal College of General Practitioners (RCGP) Research and Surveillance Centre (RSC) database, exploring four themes: AA epidemiology, mental health comorbidities, autoimmune/atopic associations and common infections.In the epidemiology theme, we will describe the incidence and point prevalence of AA overall and by age, sex and sociodemographic factors. Healthcare utilisation (primary care visits and secondary care referrals) and treatments for AA will also be assessed. In the mental health theme, we will explore the prevalence and incidence of mental health conditions (anxiety, depressive episodes, recurrent depressive disorder, adjustment disorder, agoraphobia, self-harm and parasuicide) in people with AA compared with matched controls. We will also explore the mental health treatment patterns (medication and psychological interventions), time off work and unemployment rates. Within the autoimmune/atopic associations theme, we will examine the prevalence of atopic (atopic dermatitis, allergic rhinitis, asthma) and autoimmune conditions (Crohn's disease, ulcerative colitis, coeliac disease, type 1 diabetes, Hashimoto's thyroiditis, Graves' disease, rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, systemic lupus erythematosus (SLE), polymyalgia rheumatica, Sjögren's syndrome, psoriasis, vitiligo, multiple sclerosis, pernicious anaemia) in people with AA compared with matched controls. We will also estimate the incidence of new-onset atopic and autoimmune conditions after AA diagnosis. Within the common infections theme, we will examine the incidence of common infections (respiratory tract infection, pneumonia, acute bronchitis, influenza, skin infection, urinary tract infection, genital infections, gastrointestinal infection, herpes simplex, herpes zoster, meningitis, COVID-19) in people with AA compared with matched controls. ETHICS AND DISSEMINATION: The Health Research Authority decision tool classed this a study of usual practice, ethics approval was not required. Study approval was granted by the RCGP RSC Study Approval Committee. Results will be disseminated through peer-reviewed publications. OBSERVATIONAL STUDY REGISTRATION NUMBER: NCT04239521.

Photoletter to the editor: Dermatitis herpetiformis co-localised with vitiligo in a patient with autoimmune polyglandular syndrome.

We report a case of dermatitis herpetiformis co-localised with segmental vitiligo in a 37-year-old woman with a background history of autoimmune polyglandular syndrome type 2. We propose genetic mosaicism as a possible mechanism. There has only been one previous case report in which dermatitis hepetiformis co-localised in close proximity but not exclusively within vilitigo in a patient with autoimmune thyroiditis. To our knowledge, this is the first case report of dermatitis herpetiformis co-localised exclusively to segmental vitiligo in the presence of autoimmune polyglandular syndrome.