Related Experiment Video

Updated: Aug 11, 2026

Detection of Anti-MDA5 Autoantibodies Using HeLa Cells and Immunocytochemistry with Light Microscopy
10:55

Detection of Anti-MDA5 Autoantibodies Using HeLa Cells and Immunocytochemistry with Light Microscopy

Published on: October 31, 2025

Prognosis and mortality of polymyositis and dermatomyositis patients

A Airio1, H Kautiainen, M Hakala

  • 1Rheumatism Foundation Hospital, Heinola, Finland. antti.airio@fimnet.fi

Clinical Rheumatology
|February 16, 2006
PubMed

Insights

This study found that patients with dermatomyositis (DM) have a higher mortality risk than those with polymyositis (PM), largely due to an increased risk of dying from cancer. Long-term survival rates for both conditions remain significantly lower than the general population.

Area of Science:

  • Rheumatology and Immunology
  • Epidemiology and Public Health
  • Oncology

Background:

  • Polymyositis (PM) and dermatomyositis (DM) are rare idiopathic inflammatory myopathies with significant long-term morbidity and mortality.
  • Understanding survival rates and prognostic factors is crucial for patient management and healthcare resource allocation.
  • Previous studies have varied in their findings regarding long-term outcomes and specific risk factors for PM and DM.

Purpose of the Study:

  • To evaluate the long-term survival outcomes of polymyositis (PM) and dermatomyositis (DM) patients in Finland.
  • To identify factors that predict mortality in a nationwide cohort of PM and DM patients.
  • To compare mortality risks and causes of death between PM and DM.

Main Methods:

  • A nationwide cohort of 176 PM and 72 DM patients diagnosed in Finland between 1969-1985 was identified.
  • Patients were followed up until death or August 1995, using national hospital discharge registers and diagnostic criteria by Bohan and Peter.
  • Prognostic factors assessed included gender, age, treatment delay, serum creatine kinase, ESR, corticosteroid dose, and cytostatic therapy duration.

Main Results:

  • The 5-year survival rates were 75% for PM and 63% for DM; 10-year rates were 55% for PM and 53% for DM.
  • The standardized mortality ratio for the combined PM and DM group was approximately threefold that of the general population.
  • Dermatomyositis (DM) patients had a 1.47-fold increased age- and sex-adjusted mortality risk compared to polymyositis (PM) patients, primarily driven by a 5.11-fold higher risk of cancer-related death.

Conclusions:

  • Patients with dermatomyositis (DM) face a significantly higher age-adjusted mortality risk than those with polymyositis (PM).
  • Cancer is a major cause of death in DM patients, contributing significantly to the increased mortality observed in this group.
  • Age and delayed diagnosis were significant predictors of death in PM, while cancer risk was elevated in both groups, particularly DM.

Related Concept Videos

Myocarditis III: Medical Management01:14

Myocarditis III: Medical Management

Myocarditis: Comprehensive Medical ManagementMyocarditis, the heart muscle inflammation, requires a comprehensive medical management strategy that addresses the underlying cause, provides supportive care, manages symptoms, and reduces cardiac workload.Infections and Autoimmune CausesAdminister appropriate antimicrobial therapy when an infectious agent causes myocarditis. For instance, penicillin treats infections caused by Group A Streptococcus. In cases where autoimmune processes are...
Myocarditis IV: Nursing Management01:22

Myocarditis IV: Nursing Management

Myocarditis is an inflammatory condition of the myocardium requiring meticulous nursing management for optimal patient outcomes. Effective management begins with a thorough assessment of the patient's medical history, paying close attention to past infections, autoimmune disorders, travel history, and exposure to toxins or drugs. Recent viral infections and systemic diseases are particularly relevant due to their potential role in triggering myocarditis.Physical Examination and MonitoringThe...
Myocarditis I: Introduction01:21

Myocarditis I: Introduction

Myocarditis is inflammation of the myocardium, which is the muscular layer of the heart.EtiologyMyocarditis has a diverse etiology, including a wide range of infectious and non-infectious causes:Infectious CausesViral: Common viruses include Coxsackie A and B, adenovirus, parvovirus B19, enteroviruses, and influenza A.Bacterial: Examples include infections caused by Streptococcus, Staphylococcus, and Mycoplasma species.Rickettsial: Infections like Rocky Mountain spotted fever can result in...
Rocky Mountain Spotted Fever01:26

Rocky Mountain Spotted Fever

Rocky Mountain Spotted Fever (RMSF) is a severe tick-borne illness caused by Rickettsia rickettsii, a Gram-negative, coccobacillary bacterium. This pathogen is an obligate intracellular parasite, requiring a host cell for replication. Transmission occurs through the bite of an infected tick. In the United States, the most important vectors are Dermacentor variabilis (American dog tick) and Dermacentor andersoni (Rocky Mountain wood tick), though other tick species may also serve as vectors.
Myasthenia Gravis: Overview and Treatment01:20

Myasthenia Gravis: Overview and Treatment

Myasthenia gravis is a neuromuscular transmission disorder characterized by weakness and increased fatigability of skeletal muscles. It is an autoimmune disease affecting approximately one in 2000 people, where antibodies against the α1 subunit of nicotinic acetylcholine receptors are produced.
These antibodies interfere with the function of the nicotinic receptors in three ways: by binding to the receptor and disrupting acetylcholine binding; by causing cross-linking of receptors which leads...
Myocarditis II: Clinical Features and Diagnostic Tests01:27

Myocarditis II: Clinical Features and Diagnostic Tests

Myocarditis is an inflammation of the heart muscle. The symptoms vary widely, encompassing asymptomatic presentations to severe, acute manifestations.Clinical PresentationAsymptomatic cases: In some instances, myocarditis may be asymptomatic, with the infection resolving without intervention. These cases often go undetected unless discovered incidentally through diagnostic imaging or tests conducted for other reasons.General Early Symptoms: Early symptoms of myocarditis are non-specific and can...