Incidence and remission rates of self‐reported hidradenitis suppurativa ‐ A prospective cohort study conducted in Danish blood donors

Abstract

Background A large discrepancy between physician-diagnosed and self-reported Hidradenitis suppurativa (HS) exists.Knowledge regarding incidence and remission rates of self-reported HS is missing, but may help bridge the gap in understanding between these two phenotypes.Objectives To determine the incidence and remission rates of self-reported HS, and to what degree these are affected by sex, smoking and BMI.Methods A prospective cohort of 23 930 Danish blood donors. Information on self-reported HS, symptom-localisation, sex, age, BMI and smoking status was collected at baseline and study termination. Self-reported HS fulfilled clinical obligatory diagnostic criteria. Cox proportional hazards regression analyses were conducted for both incidence and remission rates providing a hazard ratio (HR) of risk for each variable in the regression.Results Incidence rate of self-reported HS was 10.8/1000 person-years (95% confidence interval (CI): 9.9-11.7), decreasing as a function of numbers of areas affected. Female BMI points above 25 (HR = 1.11, 95% CI: 1.09-1.13), male BMI points above 25 (HR = 1.07, 95% CI: 1.04-1.11), active smoking (HR = 1.72, 95% CI: 1.15-2.57), male sex (HR = 0.55, 95% CI: 0.45-0.67) and years of age above 25 (HR = 0.97, 95% CI: 0.96-0.97) were all statistically associated with the development of self-reported HS. Remission rate of self-reported HS was 256.7/1000 person-years (95% CI: 223.9-292.6), decreasing as a function of numbers of affected areas. Symptoms in ≥3 areas (HR = 0.54, 95% CI: 0.34-0.85), active smoking (HR = 0.49, 95% CI: 0.32-0.76) and female weight loss (every percentage drop in BMI: HR = 1.07, 95% CI: 1.05-1.11) all significantly affected the remission rate.Conclusions Both incidence and remission rates of self-reported HS are high, indicating that many with self-reported HS are unlikely to be diagnosed, as they to a higher degree experience mild transient HS symptoms.

Evaluating dietary considerations in hidradenitis suppurativa: a critical examination of existing knowledge

“…The review process was initiated by a literature search, which retrieved a total of 8,259 articles. After removing duplicates, 735 articles were assessed for eligibility, and 46 were ultimately included in the study 7–52 . A flowchart depicting the selection process can be found in Figure 1.…”

“…Seven studies on weight loss's effects on HS were found (Table S1). The designs were three case series, two cohorts, and one cross‐sectional study 7,21–26 . Studies agree on significant improvement in HS severity and a higher likelihood of remission in patients with substantial weight loss.…”

“…The designs were three case series, two cohorts, and one cross-sectional study. 7,[21][22][23][24][25][26] Studies agree on significant improvement in HS severity and a higher likelihood of remission in patients with substantial weight loss. However, reports are mixed regarding the effects of BS on HS.…”

Incidence of self‐reported hidradenitis suppurativa – a commentary

“…HS epidemiology remains a very active area of interest, and numerous papers have been published from different countries including Europe, Africa and the United States 2–4 . A recent Danish study has shown a HS prevalence of 1.8% in 27765 blood donors, 5 and many of the authors have also participated in the article ‘Incidence and remission rates of self‐reported hidradenitis suppurativa ‐ a prospective cohort study conducted in Danish blood donors’ 6 object of the present commentary.…”