Abstract
The home days ratio (days at home/observation period) is an important index for evaluating the efficacy of therapy for chronic disease. To compute the home days ratio in patients treated with long-term oxygen therapy, we retrospectively studied the records of 72 consecutive patients with chronic respiratory failure who received long-term oxygen therapy from the Department of Pulmonary Medicine, Ogaki Municipal Hospital. These patients were representative of those treated with long-term oxygen therapy in terms of age, cause of hypoxemia, blood gas values, and pulmonary function. The home days ratio gradually decreased; it was 92.7±15.2% during the first year, 87.5±24.0% during the second year, and 78.5±39.7% during the third year. The home days ratios in survivors (n=39) were greater than in non-survivors (n=33). For the first year: 96.7±7.5% vs. 85.8±21.9%, p=0.034; for the second year: 99.0±2.6% vs. 71.4±31.0%, p=0.004; for the third year: 96.0±9.0% vs. 48.4±53.1%, p=0.081, for survivors and non-survivors, respectively. These data suggest that non-survivors can be distinguished from survivors soon after the start of oxygen therapy.
