Prevalence of extended treatment in pulmonary tuberculosis patients receiving first-line therapy and its association with recurrent tuberculosis in Beijing, China.

BACKGROUND: In China, it is known that extended treatment is given to patients with pulmonary TB after they have successfully completed 6 months of first-line treatment. This practice is not officially reported to the National Tuberculosis Control Programme, so there are no data on its prevalence, its possible benefits in terms of preventing recurrent disease or the costs. This study aimed to provide information, from a single TB dispensary in Beijing, China, on the prevalence of extended anti-TB treatment and its relationship with recurrent TB. METHODS: Retrospective cohort study using the electronic national TB information system and dispensary medical records. RESULTS: Of 935 patients with pulmonary TB who completed 6-7 months of first-line drug treatment, 399 (43%) were given extended treatment. This was more common in patients with smear-positive disease, and those with lung cavities and more extensive radiographic lobar involvement at the time of diagnosis. Over 3-4 years' follow-up, recurrent disease was not significantly different in patients who received extended treatment (2.8%, 11/399) as compared to those who received the standard 6-month treatment (3.7%, 20/534). The median length of extended treatment was 89 days at a median cost of US$111 for drugs and US$32 for laboratory examinations. CONCLUSIONS: This study shows that extended treatment is common in one TB dispensary in Beijing. Further studies are needed to determine the countrywide prevalence of this practice and ascertain more conclusively the apparent lack of benefit.