RT Journal Article
SR Electronic
T1 TB morbidity estimates overlook the contribution of post-TB disability: evidence from urban Malawi
JF BMJ Global Health
JO BMJ Global Health
FD BMJ Publishing Group Ltd
SP e007643
DO 10.1136/bmjgh-2021-007643
VO 7
IS 5
A1 Ewan M Tomeny
A1 Rebecca Nightingale
A1 Beatrice Chinoko
A1 Georgios F Nikolaidis
A1 Jason J Madan
A1 Eve Worrall
A1 Lucky Gift Ngwira
A1 Ndaziona Peter Banda
A1 Knut Lönnroth
A1 Denise Evans
A1 Jeremiah Chakaya
A1 Jamie Rylance
A1 Kevin Mortimer
A1 S. Bertel Squire
A1 Jamilah Meghji
YR 2022
UL http://gh.bmj.com/content/7/5/e007643.abstract
AB Introduction Despite growing evidence of the long-term impact of tuberculosis (TB) on quality of life, Global Burden of Disease (GBD) estimates of TB-related disability-adjusted life years (DALYs) do not include post-TB morbidity, and evaluations of TB interventions typically assume treated patients return to pre-TB health. Using primary data, we estimate years of life lost due to disability (YLDs), years of life lost due to premature mortality (YLL) and DALYs associated with post-TB cardiorespiratory morbidity in a low-income country.Methods Adults aged ≥15 years who had successfully completed treatment for drug-sensitive pulmonary TB in Blantyre, Malawi (February 2016–April 2017) were followed-up for 3 years with 6-monthly and 12-monthly study visits. In this secondary analysis, St George’s Respiratory Questionnaire data were used to match patients to GBD cardiorespiratory health states and corresponding disability weights (DWs) at each visit. YLDs were calculated for the study period and estimated for remaining lifespan using Malawian life table life expectancies. YLL were estimated using study mortality data and aspirational life expectancies, and post-TB DALYs derived. Data were disaggregated by HIV status and gender.Results At treatment completion, 222/403 (55.1%) participants met criteria for a cardiorespiratory DW, decreasing to 15.6% after 3 years, at which point two-thirds of the disability burden was experienced by women. Over 90% of projected lifetime-YLD were concentrated within the most severely affected 20% of survivors. Mean DWs in the 3 years post-treatment were 0.041 (HIV-) and 0.025 (HIV+), and beyond 3 years estimated as 0.025 (HIV-) and 0.010 (HIV+), compared with GBD DWs of 0.408 (HIV+) and 0.333 (HIV-) during active disease. Our results imply that the majority of TB-related morbidity occurs post-treatment.Conclusion TB-related DALYs are greatly underestimated by overlooking post-TB disability. The total disability burden of TB is likely undervalued by both GBD estimates and economic evaluations of interventions, particularly those aimed at early diagnosis and prevention.Data are available upon reasonable request. The code used in our analyses is available upon request.