Hidradenitis suppurativa (HS) is a long-standing inflammatory follicular disease presenting with multiple subcutaneous nodules, abscess and fistula. In Western countries, the prevalence of HS has been estimated as 0.1%-4% of general population with a higher rate among female than male. In Okinawa prefecture, the southernmost prefecture of Japan, HS is more frequent than the other parts of Japan. The aim of this study is to find out characteristics of HS patients in Okinawa, and to reveal the difference between East Asia and Western countries.
The data of all 50 HS patients, who were diagnosed at University of the Ryukyus Hospital from April 2010 to March 2018, were collected, and compared with previous studies in Japan, Korea, French, and United states.
50 HS cases included 38 males and 12 females, and age of patients ranged from 17 to 73 years old with the median disease duration of 7 years. The smoking rate and BMI of HS patients were higher than the average in Japanese and Okinawa population. The median sartorius score was 41.5 (IQR=10.5). In multivariate analysis, disease duration was associated with Sartorius score. There was a strong positive correlation with serum CRP (r=0.75, P<0.001), and an inverse correlation with serum albumin level (r=-0.67. P<0.001) to Sartorius score. Overall, in East Asia, HS was common in male; few patients had family history(1.7% vs 29.1%, p<0.001); and there were more severe Hurley stageⅢ patients (11.3% vs 3.1%, p<0.001) compared to Western countries. Comorbidity with inflammatory bowel disease and spondyloarthritis were rare in East Asia. In Western countries, patients were more obese, in contrast smoking rate was higher than in East Asia.
Our study will help to understand distinction of HS patients between East Asia and Western countries.

Clinical characteristics of Hidradenitis suppurativa patients in Okinawa Japan: Diffeerence between East Asia and Western countries