Healthcare Disparities in Alopecia Areata

Study Overview
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Brief Summary
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Alopecia areata (AA) is a common immune-mediated non-scarring alopecia often associated with substantial morbidity. There are however, limited population-based data on potential disparities in the burden of AA, including across people of different ethnicities and deprivation. We aimed to provide the first large-scale, population-based estimate of lifetime risk of AA overall and by important sociodemographic subgroups. As AA is associated with an increased burden of mental health conditions and work-related outcomes (unemployment, time off work), a detailed understanding of the burden of disease in different sociodemographic groups is vital to plan resource provision.

Detailed Description
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The overall purpose of the study is to provide an estimate of the cumulative lifetime incidence of AA in the population overall and by important sociodemographic groups. Moreover, to do a subgroup analysis in the AA population to identify health-related disparities across people in different socioeconomic strata, geographical distribution, sex and ethnic groups. The disparities that will be considered are AA associated: Mental health conditions; healthcare utilisation; and work impact (time off work and unemployment). The cumulative lifetime risk of AA was estimated at age 80 years (approximate life expectancy in the UK) using survival models, with age as the timescale and accounting for the competing risk of death. The assessment of any associations with baseline characteristics and the outcomes of interest will be assessed using Cox proportional hazards models (time to event outcomes) and Poisson regression (repeated event outcomes) models.

Official Title
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Healthcare Disparities in Alopecia Areata: UK Population-based Cohort Study

Conditions
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Alopecia Areata

Intervention / Treatment
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* Other: No intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients aged greater than 12 over the study period. Registered with the contributing primary care practice for any duration during the study period Exclusion Criteria: People diagnosed with AA before the study period.

Ages Eligible for Study
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Minimum Age: 12 Years
Maximum Age: 95 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| People with Alopecia Areata<br>Children and adults aged 12+ with new onset Alopecia Areata registered with a contributing General practitioner (GP) practice during the study period. | Other: No intervention<br>* Observational analysis of usual care only.<br>|
| People without Alopecia Areata<br>Children and adults aged 12+ without Alopecia Areata registered with a contributing GP practice during the study period. | Other: No intervention<br>* Observational analysis of usual care only.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total disease burden | Disease burden of Alopecia Areata (AA) measured using cumulative lifetime incidence against age. | Measured over 10 years - 2009 - 2018 inclusive. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of mental health conditions within patients with AA | Describe any disparities in AA related mental health conditions measured by time to first mental health diagnosis | 2 years | 
| Primary care attendance | Describe any disparities in AA healthcare utilisation measured by the number of primary care visits. | 2 years | 
| Dermatology referrals | Describe any disparities in AA healthcare utilisation measured by the number of dermatology referrals, | 2 years | 
| Psychological therapy | Describe any disparities in AA healthcare utilisation measured by the number of referrals for psychological therapy. | 2 years | 
| Psychiatric reviews | Describe any disparities in AA healthcare utilisation measured by the number of referrals to psychiatric review. | 2 years | 
| Unemployment | Describe any disparities in work-related impact measured by time to first recorded unemployment event. | 2 years | 
| Time off work | Describe any disparities in work-related impact measured by time to first recorded time off work sickness event. | 2 years |