Epidemiological basis of tuberculosis eradication. 9. Changes in the mortality of Danish tuberculosis patients since 1925.

The authors have carried out an analysis of the mortality among Danish patients with tuberculosis whose condition was diagnosed between 1925 and 1954 in order to obtain a picture of the trend of tuberculosis mortality over a period during which a dramatic improvement in the prognosis of the disease has taken place. The data originate from clinical records and follow-up during 10 years of all notified cases fulfilling certain conditions in Arhus, the largest provincial town in Denmark.The mortality of the patients was highest immediately after diagnosis and decreased during the 10 years they were followed. The relative changes during the follow-up period, however, appeared to be the same in all patient groups and this fact has greatly simplified the comparison of the mortality among patients diagnosed in the different calendar years.Analysis of the data according to year of diagnosis showed a consistent and substantial decrease in the mortality of young patients before the antituberculosis drugs came into use. This was true even within groups of patients with similar radiological findings. For patients over 45 years of age, however, there was no significant decrease in mortality before 1950.