. Author manuscript; available in PMC: 2016 May 1.

Published in final edited form as: Arthritis Care Res (Hoboken). 2015 May;67(5):673–680. doi: 10.1002/acr.22501

Table 1.

Characteristics of all hospitalizations and hospitalizations with myositis in the National Inpatient Sample

	Sample of all hospitalizations (n=27,990)	All myositis hospitalizations (n=15,407)	Myositis hospitalizations
	Sample of all hospitalizations (n=27,990)	All myositis hospitalizations (n=15,407)	Survived (n=14,707)	Died (n=700)
Age	62+/−19	61+/−16	60+/−16	66+/−15
Female	15,074 (54%)	10,534 (68%)	10,089 (69%)	445 (64%)
Race
White	16,781 (60%)	7,719 (50%)	7,344 (50%)	375 (54%)
African American	3,307 (12%)	3,253 (21%)	3,125 (21%)	128 (18%)
Hispanic	1,990 (7%)	1,226 (8%)	1,172 (8%)	54 (8%)
Other	1,311 (5%)	638 (4%)	597 (4%)	41 (6%)
Missing	4,601 (16%)	2,571 (17%)	2,469 (17%)	102 (15%)
Lowest income quartile	8,062 (29%)	4,387 (28%)	4,216 (29%)	171 (24%)
Charlson Index	0.9+/−1.2	0.9+/−1.1	0.9+/−1.1	1.2+/−1.3
Dermatomyositis (vs. polymyositis)	NA^*	10,023 (65%)	9,574 (65%)	449 (64%)

Patients with a discharge diagnosis of 710.3 or 710.4 were excluded from the sample of all hospital discharges (15 patients were excluded from this group).