The impact of antiretroviral therapy on tuberculosis incidence

Introduction Although HIV infection increases the likelihood of developing TB, evidence suggests that starting ART reduces the risk of TB incidence although not to the level of HIV negative people in the population. This study aims to determine the impact of ART on TB incidence in people living with HIV in the Western Cape Province of South Africa. Methods This is a retrospective cohort study using routinely collected data of HIV infected individuals aged 15 years and above from public health facilities in the Western Cape Province, South Africa, between 2007 and 2016. A Marginal Structural Model (MSM) with inverse probability of treatment weighting (IPTW) was used to estimate the effect of ART on TB incidence adjusting for measured time-dependent confounding by CD4 count. Results ART was associated with a 77.3% (95% CI, 76.7% – 78.0%) reduction in the risk of TB incidence in HIV infected patients. The overall TB incidence was 9 855 per 100 000 patient years (95% CI, 9 798 – 9 912). Patients on ART and those not on ART had a TB incidence of 3 939 and 15 329 per 100 000 patient years respectively. TB incidence was higher in males than females, and higher in patients with lower CD4 count at baseline and during follow-up. TB incidence declined with increasing ART duration and rising CD4 count but remained elevated compared to background incidence. Conclusion This study has shown that ART is highly effective at preventing TB in people living with HIV. The recent introduction of universal ART access for everyone living with HIV should contribute to further reducing TB incidence in South Africa and other high HIV and TB burden countries

Completeness of death registration in Cape Town and its health districts, 1996-2004

It is important for health planners to have timeous and accurate data on deaths. The Department of Home Affairs is responsible for the registration of deaths and the City of Cape Town has a well-established system of collating the death statistics based on vital registration, but the completeness of the death registration has not been assessed previously. The completeness was assessed for the City of Cape Town by comparing their statistics with an estimate based on data obtained from adult deaths reported in the 2001 census. A second approach assessed the trend in completeness between 1996 and 2004 by identifying three rates of mortality considered to be stable over time (non-lung and non-oesophageal cancers, the 10-14 age group and the 60+ age group) and inspecting to observe whether there was any trend apparent over time. Since deaths in most cases are under reported, and the under reporting usually differs in completeness between children and adults, child deaths from the ASSA model projection assuming that they are more complete were compared with the child deaths from the vital registration between 1996 and 2004 to check for completeness of the child vital registration data in Cape Town and its eight health districts The results show high levels of completeness in the adult deaths for Cape Town as a whole in 2001, around 95 per cent, but varying levels in the health districts. The completeness of reporting of male deaths in Cape Town declines with age, whilst completeness for females is fairly level with respect to age, with similar trends being observed in the health districts. Completeness of child (0 -4) death registration averaged around 60 per cent, about 35 per cent lower than the completeness of adult deaths in Cape Town. Cape Town as a whole and most of its health districts revealed two levels of completeness in the registration of deaths, 1996-1999 and 2001-2004 with 2000 sometimes consistent with the first and sometimes with the second period or different from either period in some of the health districts. In conclusion, the completeness estimates obtained are more rigorous from 2001 onwards suggesting that they can be reliably used to monitor trends in the levels of mortality in the city of Cape Town

COVID-19 among adults living with HIV:correlates of mortality among public sector healthcare users in Western Cape, South Africa

Abstract Introduction While a large proportion of people with HIV (PWH) have experienced SARS‐CoV‐2 infections, there is uncertainty about the role of HIV disease severity on COVID‐19 outcomes, especially in lower‐income settings. We studied the association of mortality with characteristics of HIV severity and management, and vaccination, among adult PWH. Methods We analysed observational cohort data on all PWH aged ≥15 years experiencing a diagnosed SARS‐CoV‐2 infection (until March 2022), who accessed public sector healthcare in the Western Cape province of South Africa. Logistic regression was used to study the association of mortality with evidence of antiretroviral therapy (ART) collection, time since first HIV evidence, CD4 cell count, viral load (among those with evidence of ART collection) and COVID‐19 vaccination, adjusting for demographic characteristics, comorbidities, admission pressure, location and time period. Results Mortality occurred in 5.7% (95% CI: 5.3,6.0) of 17,831 first‐diagnosed infections. Higher mortality was associated with lower recent CD4, no evidence of ART collection, high or unknown recent viral load and recent first HIV evidence, differentially by age. Vaccination was protective. The burden of comorbidities was high, and tuberculosis (especially more recent episodes of tuberculosis), chronic kidney disease, diabetes and hypertension were associated with higher mortality, more strongly in younger adults. Conclusions Mortality was strongly associated with suboptimal HIV control, and the prevalence of these risk factors increased in later COVID‐19 waves. It remains a public health priority to ensure PWH are on suppressive ART and vaccinated, and manage any disruptions in care that occurred during the pandemic. The diagnosis and management of comorbidities, including for tuberculosis, should be optimized

Risk factors for Coronavirus disease 2019 (Covid-19) death in a population cohort study from the Western Cape province, South Africa

Risk factors for coronavirus disease 2019 (COVID-19) death in sub-Saharan Africa and the effects of human immunodeficiency virus (HIV) and tuberculosis on COVID-19 outcomes are unknown. We conducted a population cohort study using linked data from adults attending public-sector health facilities in the Western Cape, South Africa. We used Cox proportional hazards models, adjusted for age, sex, location, and comorbidities, to examine the associations between HIV, tuberculosis, and COVID-19 death from 1 March to 9 June 2020 among (1) public-sector “active patients” (≥1 visit in the 3 years before March 2020); (2) laboratory-diagnosed COVID-19 cases; and (3) hospitalized COVID-19 cases. We calculated the standardized mortality ratio (SMR) for COVID-19, comparing adults living with and without HIV using modeled population estimates.Among 3 460 932 patients (16% living with HIV), 22 308 were diagnosed with COVID-19, of whom 625 died. COVID19 death was associated with male sex, increasing age, diabetes, hypertension, and chronic kidney disease. HIV was associated with COVID-19 mortality (adjusted hazard ratio [aHR], 2.14; 95% confidence interval [CI], 1.70–2.70), with similar risks across strata of viral loads and immunosuppression. Current and previous diagnoses of tuberculosis were associated with COVID-19 death (aHR, 2.70 [95% CI, 1.81–4.04] and 1.51 [95% CI, 1.18–1.93], respectively). The SMR for COVID-19 death associated with HIV was 2.39 (95% CI, 1.96–2.86); population attributable fraction 8.5% (95% CI, 6.1–11.1)

High Rates of Recurrent Tuberculosis Disease: a population-level cohort study

BACKGROUND: Retreatment tuberculosis (TB) disease is common in high-prevalence settings. The risk of repeated episodes of recurrent TB is unknown. We calculated the rate of recurrent TB per subsequent episode by matching individual treatment episodes over a period of 13 years. METHODS: All recorded TB episodes in Cape Town between 2003 and 2016 were matched by probabilistic linkage of personal identifiers. Among individuals with a first episode notified in Cape Town and who completed their prior treatment successfully we estimated the recurrence rate stratified by subsequent episode and HIV status. We adjusted person-time to background mortality by age, sex, and HIV status. RESULTS: A total of 292 915 TB episodes among 263 848 individuals were included. The rate of recurrent TB was 16.4 per 1000 person-years (95% CI, 16.2-16.6), and increased per subsequent episode (8.4-fold increase, from 14.6 to 122.7 per 1000 from episode 2 to 6, respectively). These increases were similar stratified by HIV status. Rates among HIV positives were higher than among HIV negatives for episodes 2 and 3 (2- and 1.5-fold higher, respectively), and the same thereafter. CONCLUSIONS: TB recurrence rates were high and increased per subsequent episode, independent of HIV status. This suggests that HIV infection is insufficient to explain the high burden of recurrence; it is more likely due to a high annual risk of infection combined with an increased risk of infection or progression to disease associated with a previous TB episode. The very high recurrence rates would justify increased TB surveillance of patients with >1 episode

Local-level mortality surveillance in resource-limited settings: a case study of Cape Town highlights disparities in health

OBJECTIVE: To identify the leading causes of mortality and premature mortality in Cape Town, South Africa, and its subdistricts, and to compare levels of mortality between subdistricts. METHODS: Cape Town mortality data for the period 2001-2006 were analysed by age, cause of death and sex. Cause-of-death codes were aggregated into three main cause groups: (i) pre-transitional causes (e.g. communicable diseases, maternal causes, perinatal conditions and nutritional deficiencies), (ii) noncommunicable diseases and (iii) injuries. Premature mortality was calculated in years of life lost (YLLs). Population estimates for the Cape Town Metro district were used to calculate age-specific rates per 100 000 population, which were then age-standardized and compared across subdistricts. FINDINGS: The pattern of mortality in Cape Town reflects the quadruple burden of disease observed in the national cause-of-death profile, with HIV/AIDS, other infectious diseases, injuries and noncommunicable diseases all accounting for a significant proportion of deaths. HIV/AIDS has replaced homicide as the leading cause of death. HIV/AIDS, homicide, tuberculosis and road traffic injuries accounted for 44% of all premature mortality. Khayelitsha, the poorest subdistrict, had the highest levels of mortality for all main cause groups. CONCLUSION: Local mortality surveillance highlights the differential needs of the population of Cape Town and provides a wealth of data to inform planning and implementation of targeted interventions. Multisectoral interventions will be required to reduce the burden of disease