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Twelve- or 24-Hour Oxygen Therapy: Why a Clinical Trial?

Claude Lenfant, MD
JAMA. 1980;243(6):551-552. doi:10.1001/jama.1980.03300320043025.
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The question posed at the Sugarloaf Conference is significant, and finding an answer important, because of the high prevalence of COPD and the magnitude of the public health problem it represents. It is estimated that 8 to 9 million people in the United States have COPD, and for about 1 million of these, activity is limited. Obviously, with such numbers, personal suffering and societal losses are considerable. Present knowledge does not provide a basis for effective prevention of the disease or for a cure, once it is established. In many instances the lingering course ends in death. Today COPD ranks sixth among the leading causes of death in the United States, having reached 44,000 deaths in 1976, an increase of 44% over the number in 1968.

The progressive hypoxia that is characteristic of COPD is the major cause of morbidity and can lead to cor pulmonale, a complication of hypoxia


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