Author:
Foerster Milena,Anele Angelica,Adisa Charles,Galukande Moses,Parham Groesbeck,Zietsman Annelle,Oyamienlen Christopher Sule,Iwuoha Kingsley Chukwunyere,Ezeigbo Esther,Bakengesa Evelyn,Kaggwa Agnes,Naamala Allen,Nteziryayo Anne,Nakazibwe Teopista,Pinder Leeya F,Walubita Emily,Pontac Johanna,Anderson Benjamin O,McKenzie Fiona,Schüz Joachim,dos Santos Silva Isabel,McCormack Valerie
Abstract
Abstract
Accurate survival estimates are needed for guiding cancer control efforts in sub-Saharan Africa, but previous studies have been hampered by unknown biases due to excessive loss to follow-up (LTFU). In the African Breast Cancer—Disparities in Outcomes Study, a prospective breast cancer cohort study, we implemented active mobile health follow-up, telephoning each woman or her next-of-kin (NOK) trimonthly on her mobile phone to update information on her vital status. Dates of every contact with women/NOK were analyzed from diagnosis in 2014–2017 to the earliest of September 1, 2018, death, or 3 years postdiagnosis. The cumulative incidence of being LTFU was calculated considering deaths as competing events. In all, 1,490 women were followed for a median of 24.2 (interquartile range (IQR), 14.2–34.5) months, corresponding to 8,529 successful contacts (77% of total contacts) with the women/NOK. Median time between successful contacts was 3.0 (IQR, 3.0–3.7) months. In all, 71 women (5.3%) were LTFU at 3 years: 0.8% in Nigeria, 2.2% in Namibia, and 5.6% in Uganda. Because of temporary discontinuity of active follow-up, 20.3% of women were LTFU after 2 years in Zambia. The median time to study notification of a death was 9.1 (IQR, 3.9–14.0) weeks. Although the present study was not a randomized controlled trial, in this cancer cohort with active mobile health follow-up, LTFU was much lower than in previous studies and enabled estimation of up-to-date and reliable cancer survival.
Funder
Susan G. Komen
International Agency for Research on Cancer
National Institutes of Health
Publisher
Oxford University Press (OUP)