Adverse events and patients' perceived health-related quality of life at the end of multidrug-resistant tuberculosis treatment in Namibia

Abstract

PURPOSE:The health-related quality of life (HRQoL) of patients completing multidrug-resistant tuberculosis (MDR-TB) treatment in Namibia and whether the occurrence of adverse events influenced patients' rating of their HRQoL was evaluated.PATIENTS AND METHODS:A cross-sectional analytic survey of patients completing or who recently completed MDR-TB treatment was conducted. The patients rated their HRQoL using the simplified Short Form-™ (SF-8) questionnaire consisting of eight Likert-type questions. Three supplemental questions on the adverse events that the patients may have experienced during their MDR-TB treatment were also included. Scoring of HRQoL ratings was norm-based (mean =50, standard deviation =10) ranging from 20 (worst health) to 80 (best health), rather than the conventional 0-100 scores. We evaluated the internal consistency of the scale items using the Cronbach's alpha, performed descriptive analyses, and analyzed the association between the patients' HRQoL scores and adverse events.RESULTS:Overall, 36 patients (20 males, 56%) aged 17-54 years (median =40 years) responded to the questionnaire. The median (range) HRQoL score for the physical component summary was 58.6 (35.3-60.5), while the median score for the mental component summary was 59.3 (26.6-61.9), indicating not-so-high self-rating of health. There was good internal consistency of the scale scores, with a Cronbach's alpha value of >0.80. In all, 32 (89%) of the 36 patients experienced at least one adverse drug event of any severity during their treatment (median events =3, range 1-6), of which none was life-threatening. The occurrence of adverse events was not related to HRQoL scores. For patients reporting zero to two events, the median (range) HRQoL score was 56.8 (44.4-56.8), while for those reporting three or more events, the median score was 55.2 (38.6-56.8); P=0.34 for difference between these scores.CONCLUSION:Patients completing treatment for MDR-TB in Namibia tended to score moderately low on their HRQoL, using the generic SF-8 questionnaire. The occurrence of adverse events did not lead to lower HRQoL scores upon treatment completion.