Prevalence Of Hidradenitis Suppurativa Research Articles

Comprehensive Codified Algorithms to Identify the Underestimated Burden of Hidradenitis Suppurativa in the United States.

Hidradenitis suppurativa (HS) is a painful, inflammatory skin disease associated with a high disease burden and long diagnostic delay. Prevalence estimates of HS vary widely in the literature owing to differing estimation methodologies. This study aimed to apply stepwise algorithms to estimate the prevalence of possible/diagnosed cases of HS in the US. This was a retrospective cohort study in adult and pediatric patients with HS which utilized data from four US databases (MarketScan [Medicare and Medicaid] andOptum [electronichealth record (EHR) andClinformatics Data Mart (CDM)]). Patients withpossible/diagnosed HS were identified using two algorithms (termed Algorithm 1 and Algorithm 2), which assessed symptoms such as multiple skin boils in site-specific areas based on international classification of disease (ICD) codes. Patients with diagnosed HS were defined as having ≥ 2 outpatient or ≥ 1 inpatient diagnosis codes of HS. In each database, patients with continuous medical and pharmacy benefits in the 365days pre-index and 0-365days post-index periods were eligible for inclusion. Across all databases, Algorithm 2 (MarketScan Medicare [N = 309,916]; MarketScan Medicaid [N = 188,783]; Optum EHR [N = 366,158]; Optum CDM [N = 173,812]) identified more patients with possible/diagnosed HS than Algorithm 1 (MarketScan Medicare [N = 194,353]; MarketScan Medicaid [N = 99,276]; Optum EHR [N = 177,957]; Optum CDM [N = 112,244]). Based on ICD-9/10 codes, the 5-year period prevalence of HS ranged from 0.06% to 0.12% across all databases, while for Algorithm 1 and Algorithm 2, this ranged from 0.27% to 0.41% and 0.49% to 0.78%, respectively. Adults and females generally had a higher 5-year period prevalence versus pediatric patients and males, respectively. This real-world study highlights that HS diagnosis codes alone may be insufficient to estimate the prevalence of HS, demonstrating the value of employing algorithms in practice which assess for parameters such as multiple skin boils in site-specific areas. Integrating robust methods to identify the prevalence of HS may improve the diagnostic delay observed in HS and improve treatment outcomes.

Hidradenitis Suppurativa in Elderly Patients: Clinical and Therapeutical Outcomes-A Review of the Literature.

The management of hidradenitis suppurativa (HS) in elderly patients presents unique challenges due to its chronic inflammatory nature, heterogeneous clinical presentation and comorbidities. While HS typically affects the anogenital and intertriginous regions, elderly patients may exhibit atypical features such as the involvement of the neck, mammary area and gluteal region. The prevalence of HS in the elderly population is lower and the average age of disease onset is higher than in patients under 65. In contrast, it is unclear whether HS in the elderly has different clinical features. The elderly frequently present multiple comorbidities, including obesity, diabetes, and heart disease, which further complicate management decisions. Therapeutic interventions must consider the frailty and increased risk of multimorbidity and adverse events in elderly patients. While systemic antibiotics remain a mainstay of HS treatment, biologic agents such as TNFα inhibitors and secukinumab offer promising options for refractory cases. However, their safety and efficacy in elderly patients, particularly those with multiple comorbidities, require careful consideration. A comprehensive approach to managing HS in elderly patients involves not only pharmacological interventions but also lifestyle modifications and surgical options where appropriate. Multidisciplinary collaboration between dermatologists, geriatricians and other specialists is essential for tailoring treatment strategies and optimizing long-term outcomes and quality of life in special population.

Epidemiology and clinical correlates of hidradenitis suppurativa in primary care in Italy.

Hidradenitis suppurativa (HS) is a persistent skin disorder that is characterized by painful lesions or pus-filled lumps, mostly occurring in areas where the skin flexes. It is a disfiguring condition that significantly reduces the quality of life of those affected. Developing new, effective treatments for HS is crucial, but it is important that it be recognized and diagnosed early, especially in primary care settings. To assess the epidemiology and clinical correlates of HS in a primary care setting. The study utilized the Italian Health Search Database (HSD). A case-control design was adopted to investigate the clinical correlates of HS. Cases were classified as either "definite" or "probable" using an operational algorithm. Up to 10 controls were matched to each case based on factors such as calendar period, age, sex, and duration of follow-up. Cumulative prevalence of HS increased from 0.06% in 2002 to 0.46% in 2021. When only "definite" cases were considered, the prevalence was almost 10 times lower (0%-0.02%). Several clinical correlates were found to be positively associated with HS, including obesity, dyslipidemia, hypertension, autoimmune/inflammatory diseases, and depression. This study found that correct diagnoses of HS were made, as demonstrated by the expected relationship with clinical correlates. These associations were consistent when probable cases were included in the analysis. This evidence could serve as a foundation for proposing a decision support system for general practitioners to help identify HS in individuals with certain coexisting conditions.

The role of diet in managing hidradenitis suppurativa: a review of current evidence and future directions.

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition wish a complex pathogenesisinfluenced by multiple factors, including diet. This manuscript summarizes current literature onthe potential role of diet in HS management.Various dietary interventions, including the Mediterranean diet, elimination diets and specific nutrient supplementation, have shown promise in individual cases and observational studies. However, the heterogeneous nature of HS and the lack of controlled prospective studies limit the ability to make general dietary recommendations. Demographic factors influencing dietary habits and HS prevalence are also discussed. While food quality appears to be a crucial factor, more research is needed to establish definitive links between specific dietary components and HS outcomes. Future controlled clinical trials are necessary to develop evidence-based dietary guidelines for HS patients, considering individual variability and demographic factors.

Hidradenitis suppurativa: definition, epidemiology, etiology, diagnosis (part 1)

Hidradenitis suppurativa (HS) is a chronic recurrent skin disease characterized by development of autoimmune inflammation in the infundibulum of the hair follicle and apocrine sweat glands located in the axillary, inguinal, anogenital regions, submammary folds, near the areola of mammary glands and the umbilical region. HS is difficult to treat and has an extremely negative impact on the quality of life. HS is separated into a distinct clinical entity fundamentally different in etiopathogenesis from acute bacterial hidradenitis. The exact prevalence of HS is unknown, it varies greatly in different studies ranging from 0.03 to 4% in general population. The detection of IL-1β, IL-23, and IL-17 in the lesions indicates the key role of autoimmune inflammation involving Th17-lymphocytes in the pathogenesis of HS. Risk factors include smoking, obesity, mechanical friction, genetic predisposition. The diagnosis of HS relies on three obligatory criteria: characteristic distribution, typical morphology of the lesions and relapsing, chronic disease course. There is no “gold standard” in assessing the severity of the disease, since all available scoring systems have many limitations, therefore many questions regarding this disease remain unsolved at present — from terminology and clear and most objective assessment criteria for the severity of the process to the development of native clinical guidelines.

The Global Hidradenitis Suppurativa Atlas Methodology: Combining Global Proportions in a Pooled Analysis

Introduction: Data concerning the global burden of hidradenitis suppurativa (HS) are limited. Reported prevalence estimates vary between 0.0003% and 4.1%, and data from various geographical regions are still to be collected. Previously reported prevalences have been limited by the methodological approach and source of data. This has resulted in great heterogeneity as prevalence data from physician-diagnosed cases poorly match those of self-reported apparent HS disease. Methods: The Global Hidradenitis Suppurativa Atlas (GHiSA) introduces an innovative approach to determine the global prevalence of HS. This approach involves using a previously validated questionnaire to screen apparently healthy adults accompanying a patient to a non-dermatological outpatient clinic visit in a hospital or a private/family medicine clinic. The screening questionnaire (i.e., the index test) is combined with a subsequent physician-based in-person validation (i.e., the reference standard) of the participants who screen positive. Approximately ten percent of the screen-negative participants are also clinically assessed to verify the diagnostic precision of the test. The local prevalence (pi) will be estimated from each country that submits the number of patients who are HS positive according to the index test and clinical examination (n), and the corresponding total number of observations (N). Conclusion: The GHiSA Global Prevalence studies are currently running simultaneously in 58 countries across six continents (Africa, Europe, Australia, North America, South America, and Asia). The goal of the combined global proportion is the generation of a single summary (i.e., proportional meta-analysis), which will be done after a logit transformation and synthesized using a random-effects model. The novel standardization of the Global Prevalence Studies conducted through GHiSA enables direct international comparisons, which were previously not possible due to substantial heterogeneity in past HS prevalence studies.

Autoimmune, Autoinflammatory Disease and Cutaneous Malignancy Associations with Hidradenitis Suppurativa: A Cross-Sectional Study.

Hidradenitis suppurativa (HS) is a debilitating cutaneous disease characterized by severe painful inflammatory nodules/abscesses. At present, data regarding the epidemiology and pathophysiology of this disease are limited. To define the prevalence and comorbidity associations of HS. This was a cross-sectional study of EPICTM Cosmos© examining over 180 million US patients. Prevalences were calculated by demographic and odds ratios (OR) and identified comorbidity correlations. All examined metabolism-related, psychological, and autoimmune/autoinflammatory (AI) diseases correlated with HS. The strongest associations were with pyoderma gangrenosum [OR 26.56; confidence interval (CI): 24.98-28.23], Down syndrome (OR 11.31; CI 10.93-11.70), and polycystic ovarian syndrome (OR 11.24; CI 11.09-11.38). Novel AI associations were found between HS and lupus (OR 6.60; CI 6.26-6.94) and multiple sclerosis (MS; OR 2.38; CI 2.29-2.48). Cutaneous malignancies were largely not associated in the unsegmented cohort; however, among Black patients, novel associations with melanoma (OR 2.39; CI 1.86-3.08) and basal cell carcinoma (OR 2.69; CI 2.15-3.36) were identified. International Classification of Diseases (ICD)-based disease identification relies on coding fidelity and diagnostic accuracy. This is the first study to identify correlations between HS with melanoma and basal cell carcinoma (BCC) among Black patients as well as MS and lupus in all patients with HS.

Prevalence and Characteristics of Hidradenitis Suppurativa in the Northern Finland Birth Cohort 1986 Study: A Cross-sectional Study of 2,775 Subjects.

A negative stigmatization related to hidradenitis suppurativa may prevent patients from seeking care. Thus, a large proportion of patients with hidradenitis suppurativa may be missing from studies based on hospital data. The aim of this study was to examine the prevalence and characteristics of hidradenitis suppurativa among 2,775 subjects in the Northern Finland Birth Cohort 1986 Study (NFBC1986), who were in their mid-thirties. The prevalence of hidradenitis suppurativa was 4.0% (n = 110/2,775), being higher in females (4.8%) than in males (2.5%) (p < 0.01). Of those defined as having hidradenitis suppurativa in this study, only 4 cases (n = 4/110, 3.6%) were found to have a hidradenitis suppurativa diagnosis either in the hospital (Care Register for Health Care) or in the primary healthcare data. In an adjusted model in logistic regression analyses, hidradenitis suppurativa was significantly associated with obesity (body mass index 30-55 kg/m2) (odds ratio 3.81, 95% confidence interval 2.80-5.22), female sex (1.99, 1.53-2.61) and smoking (1.56, 1.21-2.00). In addition, there was an association between hidradenitis suppurativa and self-reported poor overall health status. Hidradenitis suppurativa seems to be common at the population level and only a minority of these patients seek care for the condition.

Hidradenitis suppurativa: new insights into disease mechanisms and an evolving treatment landscape.

Hidradenitis suppurativa (HS), also known as acne inversa, is a chronic disabling and debilitating inflammatory disease with a high unmet medical need. The prevalence of HS reported in most studies is 1-2%, although it is likely to be under-reported and estimates vary globally owing to variance in data collection methods, ethnicity, geographical location and under-diagnosis. HS is characterized by persistent, painful cutaneous nodules, abscesses and draining tunnels commonly affecting the axillary, anogenital, inguinal and perianal/gluteal areas. Over time, chronic uncontrolled inflammation results in irreversible tissue destruction and scarring. Although the pathophysiology of HS has not been fully elucidated, the tumour necrosis factor (TNF)-α and interleukin (IL)-17 pathways have an important role, involving multiple cytokines. Currently, treatment options include topical medications; systemic therapies, including repeated and/or rotational courses of systemic antibiotics, retinoids and hormonal therapies; and various surgical procedures. The anti-TNF-α antibody adalimumab is currently the only biologic approved by both the US Food and Drug Administration and the European Medicines Agency for HS; however, its efficacy varies, with a clinical response reported in approximately 50% of patients in phase III trials. HS is a rapidly evolving field of discovery, with a diverse range of agents with distinct mechanisms of action currently being explored in clinical trials. Several other promising therapeutic targets have recently emerged, and agents targeting the IL-17 and Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathways are the most advanced in ongoing or completed phase III clinical trials. Alongside limited therapeutic options, significant challenges remain in terms of diagnosis and disease management, with a need for better treatment outcomes. Other unmet needs include significant diagnostic delays, thus missing the therapeutic 'window of opportunity'; the lack of standardized outcome measures in clinical trials; and the lack of established, well-defined disease phenotypes and biomarkers.

Hidradenitis suppurativa tarda: defining an understudied elderly population.

Hidradenitis suppurativa (HS) is a chronic, devastating, multifactorial skin disease. Patients generally develop HS after puberty and the prevalence of the disease is assumed to decrease with higher age. Data outside the usual age range are limited, especially for elderly patients. To investigate the prevalence, clinical characteristics and associated comorbidities among the elderly HS population. Data were collected through a population-wide survey-based study within the Lifelines Cohort Study in the Netherlands. The clinical characteristics of elderly patients with HS (≥ 60 years) were compared with an adult population (< 60 years) with HS. The comorbidities in elderly patients with HS were compared with those of a non-HS sex- and age-matched elderly population in a 1 : 4 ratio. HS in the elderly was defined as active HS in patients aged 60 years and older. Within the HS elderly group, two subgroups were defined, late-onset HS (HS developed after 60 years of age) and persistent HS (HS developed from a younger age but continuing after 60 years of age). Within the Lifelines cohort 209 elderly patients with HS were identified as well as an adult (< 60 years) group with HS (n = 793) and a non-HS sex- and age-matched control elderly group (n = 810). The prevalence of HS among the elderly bootstrap analysis population was 0.8% [95% confidence interval (CI) 0.4-1.2]. A significantly higher age of HS symptom onset was found compared with the adult HS group: respectively, 40 vs. 23 years (odds ratio 1.056, 95% CI 1.05-1.07). Among the elderly HS cohort (in the Discussion, the HS tarda cohort) a female : male ratio of 1.7 : 1.0 and a higher family history for HS were found. Moreover, elderly patients with HS had a significantly higher risk of having HS-associated comorbidities compared with the sex- and age-matched controls. The prevalence of HS in the elderly is not rare. Among the elderly a shift from female predominance towards a lower female: male ratio in HS is observed. In addition, HS in the elderly showed significant variation in age of onset and involved body areas. Moreover, elderly patients with HS were more susceptible to multimorbidity. Finally, we propose defining HS in the elderly as 'HS tarda' and subdividing it as late-onset and persistent HS tarda.

Epidemiology of hidradenitis suppurativa

Hidradenitis suppurativa (HS) is a chronic, inflammatory, recurrent skin disease affecting hair follicles in predominantly intertriginous areas, characterized by deep, painful nodules and abscesses, fistulas, sinus tracts, and scarring. The estimated global prevalence of HS is highly variable, as revealed in a growing body of published literature, and ranges from 0.053% to 4.1%. In North American and European patients, HS is three times more common in women than men, whereas in South Korea and Japan, male predominance is found. The disease most frequently manifests itself between the ages of 18 and 29. Numerous published studies have reported the association between smoking, obesity, and HS, although there are limitations in confirming the causal relationship due to the retrospective design of the available studies.Case-control studies have frequently evaluated the association between HS, metabolic syndrome, and other systemic comorbidities. Due to increased mental health problems, a higher risk of suicide in patients with HS has been reported. We provide up-to-date evidence about the epidemiology, genetic and environmental risk factors, comorbidities, and quality of life of patients with HS. The divergence in HS frequency, possibly due to differences in populations and methodologies, remains to be explained in future worldwide studies.

Investigating Adiposity-Related Metabolic Health Phenotypes in Patients with Hidradenitis Suppurativa: A Cross-Sectional Study.

Obesity and hidradenitis suppurativa (HS) are related through meta-inflammation and are both associated with increased cardiometabolic risk. Notwithstanding, cardiometabolic pathology is not uniform in obesity and a subset of individuals with excess adiposity exhibit a healthy metabolic profile. Whilst the incidence of cardiometabolic endpoints and transitions across different adiposity-related body composition phenotypes within several populations and across different ethnicities have been investigated, data regarding metabolic health (MetH) and body composition phenotypes in individuals with HS are lacking. The objective of this study was to evaluate the relationship between different body composition phenotypes in individuals with HS. This was a cross-sectional study of 632 individuals with and without HS from a population with a high prevalence of both obesity and HS. A total of four body composition phenotypes were generated based on BMI and metabolic status (defined using either the metabolic syndrome definition or the homeostasis model of insulin resistance (HOMA-IR)): metabolically healthy overweight/obese (MHOWOB), metabolically unhealthy overweight/obese (MUOWOB), metabolically healthy normal weight (MHNW), and metabolically unhealthy normal weight (MUNW). Generally, subjects with HS exhibited a worse metabolic profile with higher levels of indices of central adiposity measures (including Visceral Adiposity Index and waist circumference), systolic blood pressure and markers of insulin resistance, as well as a higher prevalence of the metabolic syndrome. Moreover, when sub-stratified into the different body composition phenotypes, individuals with HS typically also demonstrated adverse metabolic characteristics relative to controls matched for both adiposity and metabolic health, particularly in the normal weight category and despite being classified as metabolically healthy. Being metabolically unhealthy in addition to being overweight/obese increases an individual's risk of HS. Metabolic risk-assessment should be prioritized in the clinical management of individuals with HS even in those who are lean. Patients attending HS clinics provide a valuable opportunity for targeted cardiovascular risk reduction with respect to the management of both obesity and metabolic health.

Clinical-Epidemiological Characteristics of Hidradenitis Suppurativa: A Retrospective Cohort Study from a Tertiary Care Centre in Northern Israel.

Hidradenitis suppurativa (HS) is characterised by inflamed lesions that typically appear in apocrine-rich flexural areas. Although studies have reported clinical and epidemiological data from western countries, data from the Middle East are scarce. The aim of this study is to characterise the differences in the clinical characteristics of patients with HS of Arab and Jewish ancestry and review the clinical characteristics, the course of the disease, the comorbidities, and the response to treatment. This is a retrospective study. We collected clinical and demographic data from patient files between 2015-2018 at the Rambam Healthcare Campus dermatology clinic-a tertiary hospital located in the north of Israel. Our results were compared to those of a previously published Israeli control group registered in Clalit Health Services. Of the 164 patients with HS, 96 (58.5%) were men and 68 (41.5%) were women. The average age at diagnosis was 27.5 years and the average latency between the onset and diagnosis of the disease was 4 years. We found a higher adjusted prevalence of HS in Arab patients (56%) than in their Jewish counterparts (44%). Gender, smoking, and obesity, as well as axilla and buttock lesions, were risk factors for severe HS, with no differences between ethnicities. No differences were documented in comorbidities and in response to adalimumab, with a high overall response rate of 83%. Our findings revealed differences between Arab and Jewish patients with HS in terms of incidence and gender predominance, while no differences were documented in comorbidities and response to adalimumab.

Knowledge, attitudes, and perceptions of hidradenitis suppurativa among young adults in Singapore

The prevalence of hidradenitis suppurativa (HS) is 0.00033% to 4.10% globally. Few epidemiological studies derive from Asia, with social stigmatization postulated to result in under-diagnosis. This study aimed to assess the self-reported prevalence of HS, and the knowledge, attitudes, and perceptions towards HS among Singaporean young-adults. A cross-sectional study (n=158) was conducted by anonymous online questionnaire. The association between demographic factors and risk of potentially undiagnosed HS was evaluated using multivariable logistic regression. Differences between attitude-perception scores by demographic factors and knowledge of HS were tested using two-sample t-tests. The prevalence of diagnosed and potentially undiagnosed HS was 0.63% and 8.9%, respectively. Non-Chinese had significantly higher social attitude-perception scores than Chinese (P=.029). Females had significantly higher social (P=.048) as well as economic and work (P=.037) attitude-perception scores than males. Those with knowledge of HS had significantly higher attitude-perception scores for interpersonal (P=.031) and social (P=.0052) subsections. Small sample size, low frequency of HS cases, and self-reported prevalence may not generalize to the broader population in Singapore. Our results suggest a potential underdiagnosis of HS. Non-Chinese stigmatize HS less than Chinese, and females less than males. Individuals with knowledge of HS might be more open to interpersonal and social interactions with HS sufferers.

Epidemiology and comorbidity of hidradenitis suppurativa in Korea for 17 years: A nationwide population-based cohort study.

Hidradenitis suppurativa (HS) is associated with various metabolic and autoimmune diseases. The epidemiology has been analyzed in various studies worldwide. However, epidemiological data on HS for Asian populations are limited. This study aimed to analyze the change in the prevalence and incidence of HS over 17 years in South Korea using the Korean National Health Insurance Service (NHIS) database. This study also evaluated the comorbidities in patients with HS. Population-based data from the NHIS database of Korea were obtained between January 2003 and December 2019. Odds ratios were estimated to determine the association between comorbidities and HS during the study period. Hazard ratios for the risk of incident comorbidities in patients with HS were obtained using the multivariableCox proportionalhazardanalysis. This study included 45 511 patients with HS and 910 220 controls matched for age, sex, insurance type, and income level. The incidence rate of HS per 1 000 000 person-years in Korea increased from 11.69 in 2003 to 78.78 in 2019. The annual prevalence per 1 000 000 people also increased from 34.68 in 2003 to 140.10 in 2019, showing a similar trend. Many comorbidities, including atopic, metabolic and end-organ, autoimmune/inflammatory, and psychiatric diseases were associated with HS at baseline. In many diseases, the risk of incident comorbidities in patients with HS was higher than that in controls. The incidence and prevalence of HS in Korea have increased over the past 17 years. Various comorbidities, including allergic diseases, hypertension, diabetes mellitus, dyslipidemia, myocardial infarction, chronic hepatitis and cirrhosis, chronic kidney disease, inflammatory bowel diseases, rheumatoid arthritis, vitamin D deficiency, and psychiatric diseases, were associated with HS. Physicians need to keep in mind and closely monitor these comorbidities in patients with HS.

Importance of a multi-tiered treatment approach for intellectually and developmentally disabled patients with hidradenitis suppurativa.

Hidradenitis suppurativa (HS) is a chronic, debilitating skin condition that is characterized by painful pustules, nodules, abscesses, and sinus tracts. The complicated and fast-evolving treatment of HS consists of a multi-tiered approach that includes, antibacterial, antihormonal, anti-inflammatory, and surgical options. Studies have demonstrated an earlier age of onset and increased prevalence of HS in patients with intellectual and developmental disability (IDD) compared to patients without IDD. To explore the use of an intensive multi-tiered HS management algorithm that requires monthly office visits, monthly intravenous therapy, and several daily treatment modalities in an HS population with IDD, we conducted an IRB-approved retrospective chart review of HS patients treated at the Albert Einstein College of Medicine-Montefiore HS Center (HSC) with diagnoses of concurrent IDD to investigate their demographic and diagnostic characteristics, as well as the spectrum of therapies employed in this cohort. A total of 22 HS patients with concomitant IDD, including trisomy 21, unspecified intellectual disability, autism spectrum disorder, and trisomy 13 were identified. Therapies utilized in this cohort for HS included topical and oral antibiotics, spironolactone, finasteride, oral contraceptive pills, infliximab, adalimumab, isotretinoin, intralesional and intramuscular triamcinolone injections, and excisional surgery. In conclusion, our findings indicate that despite the practical challenges, daily oral antibiotic regimens, anti-androgen combinations, oral retinoids, infliximab, adalimumab, and surgery collectively play important roles in treating HS patients with IDD. Our cases underscore the importance of utilizing the full range of modalities as the HS treatment algorithm continues to evolve.

Hidradenitis Suppurativa Prevalence in Nuuk, Greenland: Physician Validation of a Hidradenitis Suppurativa Questionnaire in a Greenlandic Setting

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Real-World Findings on the Characteristics and Treatment Exposures of Patients with Hidradenitis Suppurativa from US Claims Data.

Hidradenitis suppurativa (HS) is a chronic, debilitating, and painful inflammatory skin disease that significantly and negatively impacts patients' quality of life. The prevalence of HS in the USA is estimated to be 0.10%, with worldwide reports suggesting a prevalence closer to 1%. There is limited real-world evidence available on the care of patients with HS. We aimed to evaluate the trends in clinical care and treatment in the patient population with HS in the USA in a real-world setting. A cohort study was conducted using claims data from IBM MarketScan Databases, including the US Commercial Claims and Encounters with Medicare Supplemental and Coordination of Benefits (CCAE+MDCR) database and IBM US Medicaid database. The annual prevalence of HS increased from 0.06% (2008) to 0.14% (2017), and from 0.17% (2008) to 0.31% (2017) among CCAE+MDCR and Medicaid patients, respectively. Dermatologist visits increased from 31.9% (2008) to 47.8% (2019) in CCAE+MDCR patients, and decreased from 10.9% (2008) to 8.5% (2018) in Medicaid patients. Opioid use decreased from 45.4% (2008) to 25.5% (2019) among CCAE+MDCR patients, and from 71.3% (2008) to 48.1% (2018) among Medicaid patients. Only 8.4% of CCAE+MDCR patients and 5.8% of Medicaid patients were exposed to any biologic in 2018. Improved care and treatment of HS over the last decade, including the emergence of new treatments, have been accompanied by an increase in awareness and reported prevalence of the disease. However, there are still gaps in access to dermatologic care and low utilization of biologic therapies among patients with HS. INFOGRAPHIC.

Ethnoracial representation in hidradenitis suppurativa clinical trials.

Hidradenitis suppurativa (HS) is an inflammatory skin disorder characterized by recurring painful and suppurating lesions, with the disease disproportionately affecting black populations in the United States. Ethnoracial representation in clinical trials is vital to ensuring results are generalizable. The purpose of this study is to examine whether ethnic or racial disparities exist in HS clinical trials. The US National Library of Medicine clinical trials database (clinicaltrials.gov) was queried to identify HS clinical trials. Trials that did not present ethnic or racial data on either the website or publication were not considered. A total of 57 HS trials were identified. Of these, 23 trials, containing 2530 patients, included racial or ethnic data (Table 1). White patients made up 76.1% (1435/1886) of the study population, followed by Blacks or African Americans (13.7% (238/1732)), Hispanics or Latinos (7.2% (20/279), Asians (2.6% (26/1016)), American Indians or Alaska Natives (1.3% (14/1051)), and Native Hawaiians or Other Pacific Islanders (0.4% (4/926)). Our results establish a significant lack of minority ethnoracial representation in HS clinical trials. Since HS prevalence is highest among Blacks or African Americans, it is imperative that future clinical trials are conducted with a larger proportion of this population. Furthermore, clinical trials that did not report racial or ethnic information were conducted in countries with predominantly White populations, which likely skewed the results of this study and caused underreporting of these patients.

Coexistence of pachyonychia congenita and hidradenitis suppurativa: more than a coincidence.

The coexistence of pachyonychia congenita (PC) and hidradenitis suppurativa (HS) has been described in case reports. However, the pathomechanism underlying this association and its true prevalence are unknown. To determine the genetic defect underlying the coexistence of PC and HS in a large kindred, to delineate a pathophysiological signalling defect jointly leading to both phenotypes, and to estimate the prevalence of HS in PC. We used direct sequencing and a NOTCH luciferase reporter assay to characterize the pathophysiological basis of the familial coexistence of HS and PC. A questionnaire was distributed to patients with PC registered with the International Pachyonychia Congenita Research Registry (IPCRR) to assess the prevalence of HS among patients with PC. Direct sequencing of DNA samples obtained from family members displaying both PC and HS demonstrated a missense variant (c.275A>G) in KRT17, encoding keratin 17. Abnormal NOTCH signalling has been suggested to contribute to HS pathogenesis. Accordingly, the KRT17 c.275A>G variant resulted in a significant decrease in NOTCH activity. To ascertain the clinical importance of the association of HS with PC, we distributed a questionnaire to all patients with PC registered with the IPCRR. Seventy-two of 278 responders reported HS-associated clinical features (25·9%). Disease-causing mutations in KRT17 were most prevalent among patients with a dual phenotype of PC and HS (43%). The coexistence of HS and KRT17-associated PC is more common than previously thought. Impaired NOTCH signalling as a result of KRT17 mutations may predispose patients with PC to HS. What is already known about this topic? The coexistence of pachyonychia congenita (PC) and hidradenitis suppurativa (HS) has been described in case reports. However, the pathomechanism underlying this association and its true prevalence are unknown. What does this study add? A dual phenotype consisting of PC and HS was found to be associated with a pathogenic variant in KRT17. This variant was found to affect NOTCH signalling, which has been previously implicated in HS pathogenesis. HS was found to be associated with PC in a large cohort of patients with PC, especially in patients carrying KRT17 variants, suggesting that KRT17 variants causing PC may also predispose to HS. What is the translational message? These findings suggest that patients with PC have a higher prevalence of HS than previously thought, and hence physicians should have a higher level of suspicion of HS diagnosis in patients with PC.