Exploring Patient Reported Outcomes in Inherited Ichthyosis

Study Overview
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Brief Summary
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The goal of this observational study is to learn about the presence of extracutaneous manifestations in patients with congenital ichthyosis. The main question it aims to answer is: - Do patients with congenital ichthyosis experience extracutaneous manifestations? Participants will fill in questionnaires in which the investigators will explore whether patients experience extracutaneous manifestations, and if so what these manifestations entail. Examples of such questions are whether patients experience (joint) pain or whether they experience hindrance due to their complaints.

Detailed Description
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There is only limited knowledge about extracutaneous manifestations in patients with congenital ichthyosis. With this study, the investigators aim to identify extracutaneous manifestations with questionaires based on patient reported outcomes. Secondary research questions include: What is the prevalence of joint complaints in patients with congenital ichthyosis What is the influence of ichthyosis on the quality of life patients experience Furthermore, the investigators aim to discover knowledge gaps in current patient management and possible areas of improvement in patient care towards healthcare professionals.

Official Title
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Exploring Patient Reported Outcomes in Inherited Ichthyosis

Conditions
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Congenital Ichthyosis

Intervention / Treatment
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* Other: Questionnaires with patient reported outcome measures


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 16 years and older Clinically and genetically confirmed congenital ichthyosis Exclusion Criteria: <16 years of age Not able to read Dutch Not able to fill in questionnaires online or in print

Ages Eligible for Study
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Minimum Age: 16 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Congenital ichthyosis patients<br>Questionnaires | Other: Questionnaires with patient reported outcome measures<br>* Questionnaires to gain insight of the prevalence of extracutaneous manifestations and the impact of the disease on the quality of life.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Extracutaneous manifestations in general | Evaluation of possible extracutaneous manifestations patients with congenital ichthyosis exhibit. This is measured by a questionnaire the investigators have composed. The questions entail patient reported outcomes on their general health and the health issues patients experience due to ichthyosis. | Day 1 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prevalence of joint complaints measured by the Psoriasis Epidemiology Screening Tool | Prevalence of joint complaints measured by the Psoriasis Epidemiology Screening Tool (PEST). The higher the total score, the more joint complaints patients with congenital ichthyosis experience. | Day 1 | 
| Prevalence of joint complaints measured by the Early Arthritis Recognition Clinic questionnaire | Prevalence of joint complaints measured by the Early Arthritis Recognition Clinic (EARC) questionnaire. The higher the total score, the more joint complaints patients with congenital ichthyosis experience. | Day 1 | 
| Prevalence of joint complaints Early Arthritis for Psoriatic patients questionnaire | Prevalence of joint complaints measured by the Early Arthritis for Psoriatic patients (EARP) questionnaire. The higher the total score, the more joint complaints patients with congenital ichthyosis experience. | Day 1 | 
| Prevalence of joint complaints measured by the Clinical Arthritis Rule questionnaire | Prevalence of joint complaints measured by the Clinical Arthritis Rule (CARE) questionnaire. The higher the total score, the more joint complaints patients with congenital ichthyosis experience. | Day 1 | 
| Impact of ichthyosis on quality of life | Evaluation of quality of life measured by the Dermatology Life Quality Index (DLQI) questionnaire. Scores range from 0-30, where a higher score indicates that the skin disease has a bigger influence on their quality of life. | Day 1 | 
| Impact of ichthyosis on quality of life measured by Skindex-29 | Evaluation of the quality of life of patients with congenital ichthyosis measured by the Skindex-29 questionnaire. Scores ranging from >25 and >44, where a higher score indicates that the skin disease has a bigger influence on their quality of life. | Day 1 | 
| Prevalence of itch complaints | Evaluation of possible extracutaneous manifestations patients with congenital ichthyosis exhibit. This is measured by a numeric rating scale (NRS) of itch. The higher the outcome, the more itch patients experience | Day 1 | 
| Prevalence of pain complaints | Evaluation of possible extracutaneous manifestations patients with congenital ichthyosis exhibit. This is measured by a numeric rating scale (NRS) of pain. The higher the outcome, the more pain the patients experience | Day 1 |