Risk factors associated with mortality from pneumonia among patients with pneumoconiosis

BACKGROUND: The aim of this study was to evaluate factors associated with increased risk of mortality from pneumonia among patients with pneumoconiosis. METHODS: Medical records of 103 pneumoconiosis patients hospitalized for pneumonia were investigated. Seven patients who had lung cancer or other malignancy and 13 patients with insufficient medical record were excluded. Two female patients were excluded due to small number to analyze. The subjects were divided into two groups by clinical outcome of pneumonia, the deceased group and the survival group. The two groups were compared in terms of age, smoking history, episode of recent pneumonia, concomitancy of interstitial fibrosis or fungal ball infection, extent of small opacities, grade of large opacities and results of spirometry. Multiple logistic regression was applied to determine the association between these variables and mortality from pneumonia. RESULTS: The deceased group showed more frequent history of recent pneumonia (p = 0.006), higher prevalence of interstitial fibrosis (p = 0.007) and longer hospitalization period (p = 0.044). The proportion of subjects who had decreased FVC, less than 70 % of predicted value, was higher in the deceased group (p < 0.001). In multiple logistic regression, after adjusting age, smoking history, recent pneumonia, fungal ball, large opacity, profusion and FVC (or FEV(1)) less than 70 % of predicted value, history of recent pneumonia, concomitancy of interstitial fibrosis, type of pneumoconiosis and fungal ball presented statistically significant association with mortality from pneumonia. CONCLUSIONS: The concomitancy of fungal ball or interstitial fibrosis, history of recent pneumonia within last 90 days, type of pneumoconiosis, FVC less than 70 % of predicted value, FEV(1) less than 70 % of predicted value presented statistically significant association with mortality from pneumonia. More attention should be given to patients who have such factors when treating pneumonia with pneumoconiosis.