Browsing by Author "Fox, Matthew P"

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    A comparison of death recording by health centres and civil registration in South Africans receiving antiretroviral treatment
    (Journal of the International AIDS Society, 2015-12-16) Johnson, Leigh F; Dorrington, Rob E; Laubscher, Ria; Hoffmann, Christopher J; Wood, Robin; Fox, Matthew P; Cornell, Morna; Schomaker, Michael; Prozesky, Hans; Tanser, Frank; Davies, Mary-Ann; Boulle, Andrew
    Introduction: There is uncertainty regarding the completeness of death recording by civil registration and by health centres in South Africa. This paper aims to compare death recording by the two systems, in cohorts of South African patients receiving antiretroviral treatment (ART). Methods: Completeness of death recording was estimated using a capture-recapture approach. Six ART programmes linked their patient record systems to the vital registration system using civil ID numbers, and provided data comparing the outcomes recorded in patient files and in the vital registration. Patients were excluded if they had missing/invalid IDs or had transferred to other ART programmes. Results: After exclusions, 91 548 patient records were included. Of deaths recorded in patients files after 2003, 94.0% (95% CI: 93.3-94.6%) were recorded by civil registration, with completeness being significantly higher in urban areas, older adults and females. Of deaths recorded by civil registration after 2003, only 35.0% (95% CI: 34.2-35.8%) were recorded in patient files, with this proportion dropping from 60% in 2004-2005 to 30% in 2010 and subsequent years. Recording of deaths in patient files was significantly higher in children and in locations within 50km of the health centre. When the information from the two systems was combined, an estimated 96.2% of all deaths were recorded (93.5% in children and 96.2% in adults). Conclusions: South Africa’s civil registration system has achieved a high level of completeness in the recording of mortality. However, the fraction of deaths recorded by health centres is low and information from patient records is insufficient by itself to evaluate levels and predictors of ART patient mortality. Previously-documented improvements in ART mortality over time may be biased if based only on data from patient records.
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    Open Access
    Correcting mortality for loss to follow-up: a nomogram applied to antiretroviral treatment programmes in sub-Saharan Africa
    (Public Library of Science, 2011) Egger, Matthias; Spycher, Ben D; Sidle, John; Weigel, Ralf; Geng, Elvin H; Fox, Matthew P; MacPhail, Patrick; van Cutsem, Gilles; Messou, Eugène; Wood, Robin
    Background: The World Health Organization estimates that in sub-Saharan Africa about 4 million HIV-infected patients had started antiretroviral therapy (ART) by the end of 2008. Loss of patients to follow-up and care is an important problem for treatment programmes in this region. As mortality is high in these patients compared to patients remaining in care, ART programmes with high rates of loss to follow-up may substantially underestimate mortality of all patients starting ART. Methods and Findings: We developed a nomogram to correct mortality estimates for loss to follow-up, based on the fact that mortality of all patients starting ART in a treatment programme is a weighted average of mortality among patients lost to follow-up and patients remaining in care. The nomogram gives a correction factor based on the percentage of patients lost to follow-up at a given point in time, and the estimated ratio of mortality between patients lost and not lost to follow-up. The mortality observed among patients retained in care is then multiplied by the correction factor to obtain an estimate of programme-level mortality that takes all deaths into account. A web calculator directly calculates the corrected, programme-level mortality with 95% confidence intervals (CIs). We applied the method to 11 ART programmes in sub-Saharan Africa. Patients retained in care had a mortality at 1 year of 1.4% to 12.0%; loss to follow-up ranged from 2.8% to 28.7%; and the correction factor from 1.2 to 8.0. The absolute difference between uncorrected and corrected mortality at 1 year ranged from 1.6% to 9.8%, and was above 5% in four programmes. The largest difference in mortality was in a programme with 28.7% of patients lost to follow-up at 1 year. Conclusions: The amount of bias in mortality estimates can be large in ART programmes with substantial loss to follow-up. Programmes should routinely report mortality among patients retained in care and the proportion of patients lost. A simple nomogram can then be used to estimate mortality among all patients who started ART, for a range of plausible mortality rates among patients lost to follow-up.
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    Treatment response and mortality among patients starting antiretroviral therapy with and without Kaposi sarcoma: a cohort study
    (Public Library of Science, 2013) Maskew, Mhairi; Fox, Matthew P; Cutsem, Gilles van; Chu, Kathryn; MacPhail, Patrick; Boulle, Andrew; Egger, Matthias; Africa, for IeDEA Southern
    BACKGROUND: Improved survival among HIV-infected individuals on antiretroviral therapy (ART) has focused attention on AIDS-related cancers including Kaposi sarcoma (KS). However, the effect of KS on response to ART is not well-described in Southern Africa. We assessed the effect of KS on survival and immunologic and virologic treatment responses at 6- and 12-months after initiation of ART. METHODS: We analyzed prospectively collected data from a cohort of HIV-infected adults initiating ART in South Africa. Differences in mortality between those with and without KS at ART initiation were estimated with Cox proportional hazard models. Log-binomial models were used to assess differences in CD4 count response and HIV virologic suppression within a year of initiating treatment. RESULTS: Between January 2001-January 2008, 13,847 HIV-infected adults initiated ART at the study clinics. Those with KS at ART initiation (n = 247, 2%) were similar to those without KS (n = 13600,98%) with respect to age (35 vs. 35yrs), presenting CD4 count (74 vs. 85cells/mm 3 ) and proportion on TB treatment (37% vs. 30%). In models adjusted for sex, baseline CD4 count, age, treatment site, tuberculosis and year of ART initiation, KS patients were over three times more likely to have died at any time after ART initiation (hazard ratio[HR]: 3.62; 95% CI: 2.71-4.84) than those without KS. The increased risk was highest within the first year on ART (HR: 4.05; 95% CI: 2.95-5.55) and attenuated thereafter (HR: 2.30; 95% CI: 1.08-4.89). Those with KS also gained, on average, 29 fewer CD4 cells (95% CI: 7-52cells/mm 3 ) and were less likely to increase their CD4 count by 50 cells from baseline (RR: 1.43; 95% CI: 0.99-2.06) within the first 6-months of treatment. CONCLUSIONS: HIV-infected adults presenting with KS have increased risk of mortality even after initiation of ART with the greatest risk in the first year. Among those who survive the first year on therapy, subjects with KS demonstrated a poorer immunologic response to ART than those without KS.