Decreasing tuberculosis case fatality in England and Wales, 1988-2001

SETTING: Despite declining tuberculosis mortality per head of population, there was little change in tuberculosis case fatality in England and Wales from 1974 to 1987. OBJECTIVE: To determine the trend in tuberculosis case fatality for England and Wales from 1988 to 2001. DESIGN: Annual deaths to notifications ratios (DNRs) for tuberculosis were calculated using published notification and mortality data, and analysed by age group and three disease sites (central nervous system [CNS], respiratory and other). DNRs for seven disease sites (miliary, bone and joint, CNS, respiratory, genitourinary, gastrointestinal and other) were calculated for 1998 and 1999 combined, using additional data from the enhanced tuberculosis surveillance programme. RESULTS: DNR for all ages and disease sites combined fell from 9.26% in 1988 to 5.59% in 2001 (r = -0.90; 95% CI -0.97--0.70). DNRs for 1998-1999 combined were 41% for miliary disease, 17% for bone and joint disease, 8% for CNS disease, 7% for respiratory disease, 2% for genitourinary and gastrointestinal disease and 0.6% for other disease. CONCLUSIONS: Some of the decrease in DNRs may be due to improving notification rates. True declines in overall case fatality reflect increases in the proportion of tuberculosis patients in younger age groups and with low mortality extra-pulmonary disease.