Diagnoses of Hidradenitis Suppurativa in the United States, 1979-2012.

Hidradenitis suppurativa (HS) is rarely diagnosed in the United States. Delayed diagnosis is a significant problem in the management of HS. In the past decade, there has been an increase in HS research. To determine whether those efforts have led to an increase in diagnoses, an analysis of visits to physicians in the United States from 1979 to 2012 was performed, using National Center for Health Statistics (NCHS) databases. Patient visits to private physician offices, hospital outpatient departments, and emergency rooms were analyzed. An increase in visit rates at outpatient departments from 2003-2007 [6.3/100,000, 95% confidence interval (CI) 2.9-9.8] to 2008-2010 (30.4/100,000, 95% CI 13.9-46.9; p = 0.017) was found. Converting the data to estimated numbers of patients, a 7-fold increase in patients from 2002-2007 (2.5/100,000, 95% CI 1.4-3.6) to 2008-2010 (16.9/100,000, 95% CI 7.8-26.1; p = 0.003) was found. No significant increase in patient or patient visit rates were found when analyzing visits in the physician office setting or combined office and hospital settings. Localization of increased diagnosis to outpatient departments may reflect the recent increase in clinical research. NCHS data can be useful in monitoring rates of HS diagnosis as an outcome of increased awareness of the disease.