Solorzano. Inclusion body myositis: diagnosis, pathogenesis, and treatment options. Rheumatic diseases clinics of North America 2011 vol:37 iss:2 pg:173 -83, v
IBM primarily affects those older than 50, but should be considered with appropriate symptoms in those who are older than 30. It is more common in men; it presents insidiously, with a reported diagnosis mean time in the range of 1 to 9 years. IBM generally presents with quadriceps and forearm flexor weakness. Quadriceps and forearm atrophy may be seen as the presenting feature.