Andrew Strunk

Sex- and Age-Adjusted Population Analysis of Prevalence Estimates for Hidradenitis Suppurativa in the United States

Importance The true prevalence of hidradenitis suppurativa (HS) is unknown. Objective To establish standardized overall and group-specific prevalence estimates for HS in the United States. Design, Setting, and Participants This retrospective analysis included a demographically heterogeneous population-based sample of more than 48 million unique patients across all US census regions. As of October 27, 2016, a total of 47 690 patients with HS were identified using electronic health record data. Main Outcomes and Measures Standardized overall point prevalence for HS and sex-, age-, and race-specific prevalence estimates of HS in the general US population. Results Of the 47 690 patients with HS (26.2% men and 73.8% women), the overall HS prevalence in the US population sample was 0.10%, or 98 per 100 000 persons (95% CI, 97-99 per 100 000 persons). The adjusted prevalence in women was 137 per 100 000 (95% CI, 136-139 per 100 000), more than twice that of men (58 per 100 000; 95% CI, 57-59 per 100 000; P < .001). The prevalence of HS was highest among patients aged 30 to 39 years (172 per 100 000; 95% CI, 169-275 per 100 000) compared with all other age groups (range, 15-150 per 100 000; P < .001). Adjusted HS prevalences among African American (296 per 100 000; 95% CI, 291-300 per 100 000) and biracial (218 per 100 000; 95% CI, 202-235 per 100 000) patients were more than 3-fold and 2-fold greater, respectively, than that among white patients (95 per 100 000; 95% CI, 94-96 per 100 000; P < .001). Conclusions and Relevance Hidradenitis suppurativa is an uncommon, but not rare, disease in the United States that disproportionately affects female patients, young adults, and African American and biracial patients.

Incidence of hidradenitis suppurativa in the United States: A sex- and age-adjusted population analysis

Background The true incidence of hidradenitis suppurativa (HS) is unknown. Objective To determine standardized incidence estimates for HS in the United States. Methods We used a retrospective cohort analysis, including incident HS cases identified using electronic health records data for a demographically heterogeneous population‐based sample of >48 million unique patients across all 4 census regions. We calculated standardized 1‐ and 10‐year cumulative incidences for the overall population and for sex‐, age‐, and race‐specific groups. Results There were 5410 new HS diagnoses over a 1‐year period, with an incidence of 11.4 (95% confidence interval [CI], 11.1‐11.8) cases per 100,000 population. One‐year incidence in women was 16.1 (95% CI, 15.5‐16.6) per 100,000, more than twice that of men [6.8 (95% CI, 6.5‐7.2) per 100,000; P < .0001]. Age group–specific incidence was highest among patients 18 to 29 years of age [22.0 (95% CI, 21.0‐23.2) per 100,000]. Incidence among African Americans [30.6 (95% CI, 29.1‐32.2) per 100,000] was >2.5 times that of whites [11.7 (95% CI, 11.3‐12.2) per 100,000; P < .0001]. The average annual overall incidence over 10 years was 8.6 (95% CI, 8.6‐8.7) per 100,000 population. Limitations The use of deidentified claims prevented validation for a larger case subset. Conclusion HS incidence has increased over the past decade and disproportionately involves women, young adults, and African Americans.

Validation of a Case-Finding Algorithm for Hidradenitis Suppurativa Using Administrative Coding from a Clinical Database

Background: Requisite to the application of clinical databases for observational research in hidradenitis suppurativa (HS) is the identification of an accurate case cohort. Objective: To assess the validity of utilizing administrative codes to establish the HS cohort from a large clinical database. Methods: In this retrospective study using chart review as the reference standard, we calculated several estimates of the diagnostic accuracy of at least 1 ICD-9 code for HS. Results: Estimates of the diagnostic accuracy of at least 1 ICD-9 code for HS include sensitivity 100% (95% CI 98-100), specificity 83% (95% CI 77-88), positive predictive value 79% (95% CI 72-85), negative predictive value 100% (95% CI 98-100), accuracy 90% (95% CI 86-93), and kappa statistic 79% (95% CI 73-86). Conclusion: The case-finding algorithm employing at least 1 ICD-9 code for HS provides balance in achieving accuracy and adequate power, both necessary in the evaluation of a less common disease and its potential association with uncommon or even rare events.

Incidence of hidradenitis suppurativa among tobacco smokers: a population‐based retrospective analysis in the U.S.A.

The relationship between tobacco use and hidradenitis suppurativa (HS) is controversial.

Prevalence of hidradenitis suppurativa among patients with Down syndrome: a population-based cross-sectional analysis

Hidradenitis suppurativa (HS) has been linked to Down syndrome (DS).

Opioid, alcohol, and cannabis misuse among patients with hidradenitis suppurativa: A population-based analysis in the United States

Background: Patients with hidradenitis suppurativa (HS) experience chronic pain and have significant physical, emotional, and psychological disease impact. These patients may be at risk for substance abuse. Objective: To evaluate substance use disorder (SUD) among patients with HS in the United States. Methods: This cross‐sectional analysis of adult HS patients (n = 32,625) identified using electronic health records data was pulled from a population‐based sample of >50 million patients. Results: The prevalence of SUD among patients with HS was 4.0% (1315/32,625) compared to 2.0% (195,260/9,581,640) for patients without HS (P < .001). The most common forms of substance misuse among HS patients were alcohol (630/1315, 47.9% of SUD cases), followed by opioids (430/1315, 32.7% of SUD cases) and cannabis (430/1315, 29.7% of SUD cases). Patients with HS had 1.50 (95% confidence interval 1.42–1.59) times the adjusted odds of SUD compared to patients without HS. Patients with HS had significantly greater odds of SUD across demographic subgroups. The association between HS and SUD was generally stronger for patients 45 to 64 years of age, nonwhites, privately insured, and those without depressive or anxiety disorder. Limitations: SUD may not be accurately diagnosed. Conclusion: Patients with HS have higher odds of SUD and may benefit from periodic screening for substance abuse.

Hidradenitis Suppurativa Is Associated with Polycystic Ovary Syndrome: A Population-Based Analysis in the United States

Polycystic ovary syndrome (PCOS) has been linked to hidradenitis suppurativa (HS). However, evidence establishing a relationship between the two conditions is limited. We sought to determine the prevalence of PCOS among patients with HS and the strength of the association. We performed a cross-sectional analysis involving 22,990 patients with HS using clinical data from a multihealth system analytics platform comprising more than 55 million unique patients across all census regions of the United States. The prevalence of PCOS among patients with HS was 9.0%, compared with 2.9% in patients without HS (P < 0.0001). The likelihood of patients with HS having PCOS was 2.14 (95% confidence interval 2.04-2.24) times that of patients without HS, and PCOS was associated with HS across all subgroups. The strength of the HS association with PCOS was similar to that of diabetes mellitus (odds ratio 2.88, 95% confidence interval 2.83-2.93) and obesity (odds ratio 3.93, 95% confidence interval 3.87-3.99) with PCOS. The influence of disease severity on the strength of association with PCOS could not be assessed, nor could an HS phenotype for patients also having PCOS. This analysis could not establish directionality of relationship, nor causal link. In conclusion, PCOS is associated with HS, and patients with HS who have symptoms or signs of androgen excess should be screened for PCOS.

Incidence of Herpes Zoster among Patients with Hidradenitis Suppurativa: a retrospective population-based cohort analysis

fi ca n t (P 1⁄4 .6 7 ). To the Editor: With the advent of a highly effective recombinant subunit vaccine for herpes zoster (HZ), there is a need to identify which patients with inflammatory skin disease, some of whom may be candidates for immunomodulatory therapy, warrant vaccination for HZ. Weperformed a retrospective cohort analysis using the Explorys database to compare incidence of HZ among patients with and without hidradenitis suppurativa (HS). The Systematized Nomenclature of Medicine Clinical Terms hidradenitis and herpes zoster, which have one-to-one mapping with the International Classification of Diseases, Ninth Revision, codes for HS (705.83) and HZ (053), were used to identify the case cohort and those with the outcome of interest, respectively. This method of cohort identification has been validated for both conditions. The study population included patients with active status in the database from 2012 to 2017. Patients with HIV infection, malignant neoplastic disease, and a history of receipt of a tissue or organ transplant were excluded. Immunosuppression (IS) was defined as having received a prescription for adalimumab, infliximab, methotrexate, cyclosporine, azathioprine, or a glucocorticoid. The incidence ofHZ was compared between patients with HS and without HS, stratified by immunosuppressant use, on the basis of adjusted odds ratios from a logistic regression model that included terms for HS status, IS, sex, age, and the interaction between HS status and IS.

Satisfaction with care and likelihood to recommend ratings attributed to dermatology trainees

To the Editor: The Affordable Care Act directs value-based adjustments to Medicare payments that account for quality measures, including patient satisfaction. However, federally mandated or third-party vendor surveys do not capture unique considerations for academic institutions, including trainee involvement in patient care. Trainees typically have the initial, most durable, and sometimes the most consistent contact with the patient, yet little is known about care experiences attributed to them. We sought to prospectively evaluate the factors associated with highest ratings for satisfaction-withcare (SWC) and likelihood-to-recommend (LTR) attributed to dermatology trainees at Northwell Health and 6 other institutions with accredited programs ranging in size and location. Adults (n 1⁄4 1520) participated in an anonymous survey immediately after completing an encounter with 1 of 84 trainees (Table I). Survey responses, which were based on 5-point Likert scales, were dichotomized to identify factors associated with the highest ratings. Covariates having P values\.25 in bivariate analyses were included in multivariable regression models for each primary outcome. Fixed effects indicator variables were added to account for clustering. Final regression models used complete data from 81.9% (1245/1520) of patients. Highest SWC and LTR ratings were provided to trainees in 86.7% and 83% of encounters, respectively. Patients rating their skin health as good and excellent were more likely to provide highest SWC and LTR ratings, as were those rating overall experience with the health care institution as excellent (Table II). Importantly, factors such as sex concordance, postgraduate year, continuity encounters or number of prior visits with the trainee, and expecting to see a trainee had less (or no) influence on experience ratings than factors unrelated to the trainees themselves. In a study involving family medicine trainees, 92% of patients rated their satisfaction as good to excellent. Prior studies also support the association of satisfaction with self-reported health status and with system performance. With respect to achievement of training milestones, our results on satisfaction attributed to dermatology trainees should reassure training directors, faculty, and residents. If asked, most patients might also endorse the same sense of reassurance. However, based on institutional and national benchmarking, raw scores #90 points typically translate into below target percentile scores for dermatology providers. Whether ratings attributed to dermatology trainees have an influence on experience scores ultimately assigned to the provider of record needs to be explored further. Curricular opportunities might exist for trainees aimed at improving the patient experience, in particular for patients with poor skin health. Trainees must also appreciate that, as stewards of the patient experience, their halo effect facilitates learning opportunities for others. Likewise, we may speculate that institutional reputation might afford trainees initial trust from patients. In balancing the interests of programmatic training objectives, including advancement of graduated autonomy, programs can also make a deliberate effort to educate patients on its training mission, the roles of trainees and their prior education, and the responsibilities maintained by attending physicians throughout the episode of care. Institutions must also support these educational initiatives while also recognizing the complexities accounting for the patient experience.

Prevalence Estimates for Pemphigoid in the United States: a gender and age adjusted population analysis

Background: The burden of the pemphigoid group of autoimmune blistering diseases is poorly understood. Objective: To estimate standardized overall and sex‐specific, age‐specific, and race‐specific prevalence estimates for pemphigoid among adults in the United States. Methods: Cross‐sectional analysis of electronic health records data for a demographically heterogeneous population‐based sample of >55 million patients across all 4 census regions. Results: Overall pemphigoid prevalence was 0.012%, or 12 pemphigoid patients/100,000 adults. Prevalence of pemphigoid among those aged ≥60 years was 0.038%, or 37.7 cases/100,000 adults. Prevalence increased ˜2‐fold within each successive age group and was highest among patients aged ≥90 years (123.6 [95% CI 115.2‐132.5] cases/100,000 adults). Adjusted prevalence in women was 12.7 (95% CI 12.3‐13.2) cases/100,000 adults, slightly more than that in men (11.0 [95% CI 10.5‐11.6] cases/100,000 adults). Adjusted prevalences were similar for blacks (15.4 [95% CI 14.0‐17.0] cases/100,000 adults) and whites (13.5 [95% CI 13.0‐13.9] cases/100,000 adults). Limitations: Analysis of electronic health data might result in disease misclassification. Conclusion: Pemphigoid is rare in the United States. Patients aged ≥60 years comprise the majority of cases.