TY - JOUR
T1 - Demographic features of Japanese patients with sporadic inclusion body myositis
T2 - A single-center referral experience
AU - Nakanishi, Hirotaka
AU - Koike, Haruki
AU - Matsuo, Koji
AU - Tanaka, Fumiaki
AU - Noda, Tomoko
AU - Fujikake, Akifumi
AU - Kimura, Seigo
AU - Katsuno, Masahisa
AU - Doyu, Manabu
AU - Watanabe, Hirohisa
AU - Sobue, Gen
N1 - Copyright:
Copyright 2013 Elsevier B.V., All rights reserved.
PY - 2013
Y1 - 2013
N2 - Objective The incidence of sporadic inclusion body myositis (sIBM) in the Japanese population has increased, and some researchers have suggested that race and genetic background may influence the clinical features of the disease. The aim of this study was to clarify the demographic features of Japanese patients with sIBM. Methods We retrospectively evaluated the demographic features of consecutive patients who were referred to our institution between 1995 and 2011 for diagnostic muscle biopsies and who subsequently were diagnosed to have sIBM. Results Seventy-three patients comprising 54 men and 19 women received a diagnosis of sIBM during the study period. The patients were divided into two groups based on the date of diagnosis (before and including 2002, and after 2002). The annual number of patients who received a diagnosis of sIBM increased significantly from 3.6±1.6 (mean ± SD) before and including 2002 to 4.9±3.1 (mean ± SD) after 2002 (p<0.05), whereas the annual number of patients who received a diagnosis of polymyositis (PM) or dermatomyositis (DM) remained consistent from 1995 to 2011. The ratio of PM and DM to sIBM was 7.6 during the period from 1995 to 2002 and 5.5 during the period from 2003 to 2011. However, the age-adjusted annual number of patients newly diagnosed with sIBM did not increase significantly after 2002. Conclusion The number of Japanese patients with sIBM appears to have increased in recent years; however, the characteristics of the patients have not changed. Considering the increased size of the elderly population, prolonged lifespans could explain the demographic movement of sIBM in Japan.
AB - Objective The incidence of sporadic inclusion body myositis (sIBM) in the Japanese population has increased, and some researchers have suggested that race and genetic background may influence the clinical features of the disease. The aim of this study was to clarify the demographic features of Japanese patients with sIBM. Methods We retrospectively evaluated the demographic features of consecutive patients who were referred to our institution between 1995 and 2011 for diagnostic muscle biopsies and who subsequently were diagnosed to have sIBM. Results Seventy-three patients comprising 54 men and 19 women received a diagnosis of sIBM during the study period. The patients were divided into two groups based on the date of diagnosis (before and including 2002, and after 2002). The annual number of patients who received a diagnosis of sIBM increased significantly from 3.6±1.6 (mean ± SD) before and including 2002 to 4.9±3.1 (mean ± SD) after 2002 (p<0.05), whereas the annual number of patients who received a diagnosis of polymyositis (PM) or dermatomyositis (DM) remained consistent from 1995 to 2011. The ratio of PM and DM to sIBM was 7.6 during the period from 1995 to 2002 and 5.5 during the period from 2003 to 2011. However, the age-adjusted annual number of patients newly diagnosed with sIBM did not increase significantly after 2002. Conclusion The number of Japanese patients with sIBM appears to have increased in recent years; however, the characteristics of the patients have not changed. Considering the increased size of the elderly population, prolonged lifespans could explain the demographic movement of sIBM in Japan.
UR - http://www.scopus.com/inward/record.url?scp=84873516822&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84873516822&partnerID=8YFLogxK
U2 - 10.2169/internalmedicine.52.8910
DO - 10.2169/internalmedicine.52.8910
M3 - Article
C2 - 23370740
AN - SCOPUS:84873516822
VL - 52
SP - 333
EP - 337
JO - Internal Medicine
JF - Internal Medicine
SN - 0918-2918
IS - 3
ER -