Outcome in patients with idiopathic inflammatory myositis: morbidity and mortality.
OBJECTIVE
To assess the long-term outcome of a cohort of 46 patients with idiopathic myositis by assessing both health status, as measured by the SF-36, and cumulative survival probability over a 20-yr follow-up period at a single rheumatology centre. Methods and results. Forty-six patients under long-term follow-up from 1978 to 1999 were identified from our database. All patients fulfilled three out of four of the Bohan and Peter criteria for myositis. We excluded those with malignancy-associated disease and those with inclusion body myositis. Twenty-three patients (50%) had adult-onset polymyositis, 14 (30.4%) had adult-onset dermatomyositis, one had childhood-onset dermatomyositis and eight (17.4%) had an overlap syndrome (associated with either systemic lupus erythematosus or rheumatoid arthritis). During the course of the disease, seven patients (15.2%) went into full remission, eight (17.4%) had monophasic illness, nine (19.6%) had a relapsing-remitting course, 16 (34.8%) had chronic progressive illness and six (13.04%) died. All patients had significantly lower SF-36 scores in all aspects of health compared with the general population (P< or =0.001). Patients with chronic progressive illness had significantly greater bodily pain (P< or =0.05, t-test) than those with a relapsing-remitting illness, but did not differ in other aspects of health. There was no significant difference in the scores in the different domains of the SF-36 between the patients with active disease and those with inactive disease (0.05<P<0.1). Six of the 46 patients died. Cumulative survival probability was calculated. The five-year survival rate was 95% and the 10-yr survival rate 83.8%.


CONCLUSIONS
Patients with myositis report significantly poorer health compared with the general population. Health status and disease activity are important outcome measures in the assessment of patients with myositis.
Sultan
S M
SM
Centre for Rheumatology, Department of Medicine, University College Hospital, London W1P 9PG, UK.
Ioannou
Y
Y
Moss
K
K
Isenberg
D A
DA
D000328:Adult; D017677:Age Distribution; D000368:Aged; D015331:Cohort Studies; D003882:Dermatomyositis / Q000175:diagnosis* / Q000401:mortality* / Q000628:therapy; D018450:Disease Progression; D005260:Female; D006304:Health Status; D006801:Humans; D008134:Long-Term Care; D008297:Male; D008875:Middle Aged; D009017:Morbidity / Q000639:trends*; D017285:Polymyositis / Q000175:diagnosis* / Q000401:mortality* / Q000628:therapy; D011336:Probability; D011379:Prognosis; D011788:Quality of Life; D012016:Reference Values; D012042:Registries; D012720:Severity of Illness Index; D017678:Sex Distribution; D018434:Sickness Impact Profile; D016019:Survival Analysis; D006113:United Kingdom / Q000453:epidemiology