[Importance of interstitial lung disease in collagen vascular disease: analysis of outcome]

We studied length of survival and related clinical findings in 715 inpatients with collagen-vascular diseases (1984 through 1994), the diagnostic Kaplan-Meier analysis showed that patients with polymyositis/dermatomyositis and those with systemic sclerosis did not survive as long as those with other types of collagen-vascular disease. Of the patients who died 37% died of respiratory failure due to interstitial lung disease. Patients with interstitial lung disease had better outcomes than did those with idiopathic interstitial pneumonia: they were younger, had higher initial vital capacities, and fewer episodes of acute exacerbation of lung disease than did those with idiopathic interstitial pneumonia. Among patients with interstitial lung disease, those who died of polymyositis/dermatomyositis did so within 1 year, but those who died of systemic sclerosis lived longer. Interstitial lung disease is an important prognostic factor in collagen-vascular disease, and needs further evaluation.