Defaulting from tuberculosis treatment in the Netherlands: rates risk factors and trend in the period 1993-1997

The aim of this study was to assess the rate of defaulting from treatment a mong tuberculosis patients diagnosed in the Netherlands in the period 1993- 1997, whether risk groups for defaulting can be identified at the start of treatment and the trend of defaulting over time. The Netherlands Tuberculosis Register provided data on all patients diagnos ed in the Netherlands during the period 1993-1997, Defaulting probabilities were determined using Kaplan-Meier survival analysis and risk factors were identified with Cox's proportional hazard analysis, Of 7,529 patients with reported treatment outcome, 718 (10%) defaulted or l eft the country within 1 yr after starting treatment. Defaulting probabilit ies were 9% (95% confidence interval (CI) 8-10%) among 5,256 patients in lo w-risk groups, 17% (95% CI 14-19%) among 1,437 asylum seekers and 29% (95% CI 24-34%) among 836 patients in other high-risk groups (other recent immig rants, illegal immigrants, the homeless, prisoners and nationals from Easte rn Europe), Defaulting probabilities decreased over time from 12% in 1993 t o 7% in 1997, Risk groups for defaulting can be recognized at the start of treatment, The decreasing defaulting probabilities were probably due in part to shortenin g treatment from 9 to 6 months and improved follow-up of asylum seekers. Ho wever, additional measures are needed to reduce defaulting among the homele ss, recent immigrants, illegal immigrants and prisoners.