Table 2

 Favourable and poor outcome in surviving patients categorised by diagnosis

Disability (Rankin score)n (%)*Muscle strength (MRC sum score) n (%)Quality of life (phSIP) n (%)Treatment at FU n (%)
0–13–5130<128<1.6%>10.8%†NoYes‡
CTD, connective tissue disorder; DM, dermatomyositis; FU, follow-up; mal, malignancy; MRC, Medical Research Council; phSIP, physical dimension of the Sickness Impact Profile (mean phSIP score in healthy persons is 1.6%,31 median phSIP score in our study population was 10.8%, three missing values); PM, polymyositis (defined by endomysial cell infiltrates); Poss myositis, possible myositis (clinical PM with necrotising myopathy); Unsp myositis, unspecified myositis (clinical PM, with perimysial and perivascular cell infiltrates); +, with.
*Values are given for favourable and poor outcome; number of patients with neither a poor nor a favourable outcome are not shown.
†Median physical SIP score in total population.
‡Prednisone >10 mg/day or immunosuppressive drug.
PM (n = 6)
    Isolated (n = 6)0 (0)2 (33)2 (33)3 (50)1 (17)5 (83)2(33)1(17)
    + CTD (n = 0)
    + mal (n = 0)
DM (n = 41)
    Isolated (n = 37)14 (38)6 (16)22 (60)9 (24)8 (22)17 (46)14(38)15(41)
    + CTD (n = 3)2 (67)0 (0)3 (100)0 (0)0 (0)1 (33)2(67)0(0)
    + mal (n = 1)1(100)0 (0)1 (100)0 (0)0 (0)0 (0)1(100)0(0)
Unsp myositis (n = 40)
    Isolated (n = 24)7 (29)8 (33)17 (71)7 (29)5 (22)11 (47)9(38)11(46)
    + CTD (n = 16)3 (19)3 (19)13 (81)1 (6)2 (13)10 (63)3(19)8(50)
    + mal (n  = 0)
Poss myositis (n = 23)
    Isolated (n = 21)9 (43)6 (29)12 (57)6 (29)1 (5)8 (42)9(43)9(43)
    + CTD (n = 2)1 (50)1 (50)1 (50)1 (50)0 (0)1 (50)1(50)1(50)
    + mal (n = 0)
Total (%)37 (34)26 (24)71 (65)27 (25)17 (16)53 (51)41(37)45(41)