Table II.

Characteristics of patients with classic dermatomyositis

Classic DM
Department	Dermatology	Rheumatology	Both	P value
No. of patients	27	24	7
Sex
Female	25 (93%)	15 (63%)	5 (71%)	.015*
Male	2 (7%)	9 (38%)	2 (29%)
Ethnicity
Caucasian	23 (85%)	12 (50%)	6 (86%)	.014*
African American	2 (7%)	9 (38%)
Other	2 (7%)	3 (13%)	1 (14%)
Age at DM diagnosis, y	45.4 (19)	45.0 (20)	40.4 (19)	.93
Age at first DM symptoms, y	43.3 (20)	42.3 (20)	38.9 (19)	.85
Symptom onset to DM diagnosis, y	2.1 (8)	2.7 (7)	1.6 (2)	.78
Weakness
None	1 (4%)	2 (8%)		.18
2/4	3 (11%)
3/4		2 (8%)
4/4	23 (85%)	20 (83%)	7 (100%)
Neuropathy
Present	7 (26%)	6 (25%)	2 (29%)	1.0
Absent	20 (74%)	18 (75%)	5 (71%)
Dysphagia
Present	14 (52%)	17 (71%)	6 (86%)	.25
Absent	13 (48%)	7 (29%)	1 (14%)
Malignancy
Yes	7 (26%)	2 (8%)		.15
No	20 (74%)	22 (92%)	7 (100%)
ILD
Present	6 (22%)	13 (54%)	4 (57%)	.023*
Absent	21 (78%)	11 (46%)	3 (43%)
CPK†	1798 (4532)	3616 (6611)	352 (331)	.27
Aldolase†	15 (23)	27 (47)	12 (4)	.27
Muscle biopsy
c/w DM	14 (93%)	15 (94%)	4 (100%)	1.0
Not c/w DM	1 (7%)	1 (6%)

CPK, Creatine phosphokinase; c/w, consistent with; DM, dermatomyositis; ILD, interstitial lung disease.

^*P values reflect comparisons between dermatology and rheumatology.

^†Values are not normally distributed.