Trends in mortality from chronic obstructive airways disease in the United Kingdom.

Chronic bronchitis, the so called English disease, has been declining as a cause of death throughout this century in all age groups and for both sexes. Recently concern has been expressed among epidemiologists that in Britain this rapidly declining mortality has suffered a setback: the trend has been reversed and the already substantial burden of chronic obstructive airways disease is going to get worse. This view is echoed in many other countries, including the United States. The culprit is "chronic airways obstruction," a concept first devised in 1959 at a Ciba symposium' in an attempt to clarify the confusion over terminology, and now a well established clinical term. It has been reported that, although the number of deaths attributed to chronic bronchitis continues to decline, this is counterbalanced by the considerable increase in deaths classified as chronic airways obstruction.2 This has led to an actual increase in the total number of deaths due to chronic obstructive airways disease. This is undoubtedly true, but, at a time when the age structure ofthe population is rapidly changing, it is the age specific mortality rates that are important. This paper seeks to establish both the current and the long term trends through an analysis ofage specific mortality over 90 years. Terminology remains a problem and, for the purposes of this paper, ICD/9 496 will be referred to as chronic airways obstruction, and bronchitis (chronic and unqualified), emphysema, and chronic airways obstruction (ICD/9 490492 and 496) will be referred to collectively as chronic obstructive airways disease. Chronic obstructive pulmonary disease describes those conditions coded ICD/9 490496.