Risk factors and timing of default from treatment for non-multidrug-resistant tuberculosis in Moldova

Abstract

Setting: The Republic of Moldova, in Eastern Europe, has among the highest reported nationwide proportions of tuberculosis (TB) patients with multidrug-resistant tuberculosis (MDR-TB) worldwide. Default has been associated with increased mortality and amplification of drug resistance, and may contribute to the high MDR-TB rates in Moldova.

Objective: To assess risk factors and timing of default from treatment for non-MDR-TB from 2007 to 2010.

Design: A retrospective analysis of routine surveillance data on all non-MDR-TB patients reported.

Results: A total of 14.7% of non-MDR-TB patients defaulted from treatment during the study period. Independent risk factors for default included sociodemographic factors, such as homelessness, living alone, less formal education and spending substantial time outside Moldova in the year prior to diagnosis; and health-related factors such as human immunodeficiency virus co-infection, greater lung pathology and increasing TB drug resistance. Anti-tuberculosis treatment is usually initiated within an institutional setting in Moldova, and the default risk was highest in the month following the phase of hospitalized treatment (among civilians) and after leaving prison (among those diagnosed while incarcerated).

Conclusions: Targeted interventions to increase treatment adherence for patients at highest risk of default, and improving the continuity of care for patients transitioning from institutional to community care may substantially reduce risk of default.

Figure 1

Cumulative percentage of tuberculosis (TB) cases without multidrug-resistant TB (MDR-TB) in Moldova that defaulted by days after diagnosis. Diagnoses included from 2007 to 2010. Separate lines are shown for new and previously treated cases. Previously treated cases includes: relapse cases, returns from default, treatment failures and chronic cases. Horizontal arrows show the percentage that had defaulted by the end of the intensive phase of treatment (2 months) which is usually spent in hospital. Vertical arrows show the median time of default. The grey shaded area shows the 30 day period during which the highest percentage of new cases defaulted. This coincides with the month directly following the intensive (hospitalized) treatment phase.

Figure 2

Percentage of new tuberculosis (TB) incident cases without multidrug-resistant TB (MDR-TB) notified between 2007 and 2010 in Moldova that defaulted on treatment. Results are stratified by diagnosis location (civilian sector or penitentiary system) and further stratified by whether or not the patients remained in that location or were transferred in or out from the penitentiary system. Binomial confidence intervals and p-values for differences between groups are shown.

Figure 3

Maps of the percentage of tuberculosis (TB) cases without multidrug-resistant TB (MDR-TB) that defaulted on treatment by region of residence in Moldova (2007–2010). Data are stratified by (A) new and (B) previously treated cases. Note that numbers in some regions for previously treated cases are small (<10) and thus estimated regional rates should be interpreted with caution. The major cities (Chisinau (capital city), Balti and Tiraspol) are shown.