Demographic Profile of Acne Inversa (Hidradenitis Suppurativa)
Acne inversa (hidradenitis suppurativa) primarily affects young adults, with typical onset in the second to fourth decades of life, and has a female predominance (3:1, F:M ratio). 1
Prevalence and Distribution
- Prevalence is estimated at approximately 1-4% in the UK population, with European studies consistently reporting around 1% prevalence in the general population 1
- US studies using health claims databases suggest a lower prevalence of 0.05%, likely due to underdiagnosis and methodological limitations 1
- The disease typically presents after puberty with painful, deep-seated inflammatory lesions in apocrine gland-bearing areas 1
- Mean age of onset is between 20-30 years, though early onset (before age 13) has been reported in some cases and is associated with stronger genetic susceptibility and more widespread disease 1
Gender and Racial Distribution
- Female predominance is well-established with a 3:1 female to male ratio 1
- Higher prevalence has been documented among African-American and biracial individuals, with 3-fold and 2-fold greater prevalence respectively compared to white individuals 1
- The disproportionate prevalence in women and Black patients intensifies the need for early identification and management 1
Associated Risk Factors
- Strong association with obesity, with an odds ratio of 33 compared to controls 1
- Significant association with smoking, with an odds ratio of 36 compared to controls 1
- However, non-smoking patients with normal BMI are also seen in clinical practice 1
Common Comorbidities
- Higher overall comorbidity burden compared to both healthy populations and psoriasis patients 1
- Nearly doubled risk of cardiovascular-associated death compared to controls 1
- Associated with type 2 diabetes, hyperlipidemia, and hypertension 1
- Increased risk of depression and completed suicide, likely related to the chronic, painful nature of the disease and its impact on quality of life 1
- Association with inflammatory bowel disease, particularly Crohn's disease (but not ulcerative colitis) 1
- Higher prevalence of other follicular occlusion disorders:
Clinical Presentation
- Presents with painful, deep-seated, inflamed lesions in the apocrine gland-bearing areas 1
- Most commonly affects axillae, inguinal and anogenital regions 1
- May present with comedones (characteristically paired), papules, pustules, nodules, cysts, abscesses, sinus tracts, and fistulae in flexural areas 1
- Causes severe pain, pruritus, chronic discharge, and persistent malodor 1
- Long-standing disease can result in fibrosis, dermal contractures, scarring, and reduced mobility 1
Impact on Quality of Life
- Has the highest impact on patients' quality of life among all assessed dermatological diseases 2
- Can lead to social withdrawal, stigmatization, unemployment, and suicidal thoughts 3
- Significantly impairs sexual life of affected individuals 3
Key Diagnostic Considerations
- Diagnosis requires typical lesions (painful nodules, abscesses, sinus tracts, bridged scars, or open comedones) in typical sites, with chronic and recurrent presentation 1
- Disease severity is often measured using the Hurley staging system (I-III) 1
- Often diagnosed after long delays, highlighting the need for increased awareness 1