Hidradenitis suppurativa (HS) is a painful, long-term skin condition that causes abscesses and scarring on the skin. The exact cause of HS is unknown, but it occurs near hair follicles where there are sweat glands. Symptoms of HS, including pain and wound drainage, are known to have a large impact on patient quality of life. HS is often initially diagnosed as simple infections or furunculosis. Long diagnosis delays of several years are common in the UK, with the global average being 7 years. In the UK, the treatment guidelines for HS recommend the use of systemic antibiotics as part of medical therapy. However, the outcomes of antibiotics are extremely variable and some patients may experience difficulty to tolerate the antibiotic treatment for prolonged period of time. Alternative treatment options include infliximab and anakinra, which have shown promising results in clinical trials.
The purpose of this study is to describe the HS patient profile in England, including socio-demographic and clinical characteristics. This study will describe treatments and outcomes for patients with physician-diagnosed HS and undiagnosed (probable or suspected) HS. It is of public health interest to understand the health care resource use and costs to the National Health Service due to different treatments for HS. The results will allow an understanding of the real-world experience of diagnosis and treatment for patients with HS in England and highlight the need for faster diagnosis and better treatment options for HS due to the great impact on patients’ quality of life.
Hidradenitis suppurativa (HS) is a painful, long-term skin condition that causes abscesses and scarring on the skin. The exact cause of HS is unknown, but it occurs near hair follicles where there are sweat glands, usually around the groin, bottom, breasts and armpits. HS has an estimated prevalence of 0.77% in the general UK population. However, when probable undiagnosed cases are taken into consideration, this estimate increases to 1.18%-1.20%. This retrospective cohort study will describe the patient characteristics, patient journey (treatments and outcomes), and health care resource utilisation (HCRU) for patients with HS in England. The Clinical Practice Research Datalink (CPRD) linked with the Hospital Episode Statistics (HES) databases will be used to understand the real-world treatment options and outcomes for patients with physician-diagnosed HS and patients with undiagnosed (probable or suspected) HS.
Treatment outcomes (proxy measures):
• Prescription of dressings and all wound care related products
• Surgical intervention
• Duration of treatment of specific therapies
• HCRU use (GP visits) for HS: pre- and post-index
Ineffective treatment identification (proxy measures):
• Cessation of repeat prescriptions
• Treatment switches
• Length of treatment
Patient quality of life (proxy measures)
Quality of life proxy variables to be considered include (but not limited to):
• Psychiatric hospital visits (available in HES)
• Prescription of antidepressants
• Mental illness diagnosis
• Specialist referral (psychiatry etc.)
• Elixhauser comorbidities e.g., alcohol abuse, drug abuse, psychoses, depression (categorical)
HCRU:
The following resource use will be determined during the period of 730 days post-index date, including the index date. All-cause and HS-specific HCRUs will be assessed for all analyses.
All-cause and HS specific HCRUs as follow (but not limited to):
• Number of General Practitioner (GP), specialist (based on HES) visits, and specialist referrals
• Number of Accident & Emergency (A&E) admissions (based on a diagnosis acquired during the stay)
• Number of hospitalizations and the length of stay
• Procedure/surgery in a hospitalization event (HES)
• Reasons for hospitalization
• Patient classification (ordinary admission, day case admission, regular day attendee)
• Diagnoses within the hospital setting
• Number of days of dermatological support – in critical care only
• Prescriptions (GP setting) (product codes and BNF code for treatments and products)
• High-cost drugs (HCD) (hospital setting)
• Length of time on therapy (GP setting) (indication of repeat prescription schedules etc.)
Craig Currie - Chief Investigator - Pharmatelligence Limited t/a Human Data Sciences
Ellen Hubbuck - Corresponding Applicant - Pharmatelligence Limited t/a Human Data Sciences
Anastasia Lampropoulou - Collaborator - Novartis Pharmaceuticals UK Limited
Bethan Jones - Collaborator - Pharmatelligence Limited t/a Human Data Sciences
Debra Gregory - Collaborator - Harvey Walsh Ltd
Erica Malcolm - Collaborator - NOVARTIS
Hannah Matthews - Collaborator - Harvey Walsh Ltd
John Ingram - Collaborator - Cardiff University
Luca Le Treust - Collaborator - Harvey Walsh Ltd
PAULA PAMIES - Collaborator - Novartis Pharmaceuticals UK Limited
Petra Westlake - Collaborator - OPEN Health Group
Xiaocong Marston - Collaborator - Harvey Walsh Ltd
Ahmad Mahmoud - Collaborator - NOVARTIS
Bethan Jones - Collaborator - Pharmatelligence Limited t/a Human Data Sciences
Debra Gregory - Collaborator - Harvey Walsh Ltd
Emma Riley - Collaborator - NOVARTIS
Erica Malcolm - Collaborator - NOVARTIS
Hannah Matthews - Collaborator - Harvey Walsh Ltd
john forni - Collaborator - NOVARTIS
Luca Le Treust - Collaborator - Harvey Walsh Ltd
Manoharan Andiappan - Collaborator - Harvey Walsh Ltd
Mark Evans - Collaborator - OPEN Health Group
PAULA PAMIES - Collaborator - Novartis Pharmaceuticals UK Limited
Petra Westlake - Collaborator - OPEN Health Group
Sara Jenkins-Jones - Collaborator - Pharmatelligence Limited t/a Human Data Sciences
Sue Beecroft - Collaborator - Harvey Walsh Ltd
HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;Patient Level Index of Multiple Deprivation