Using verbal autopsy to assess the prevalence of HIV infection among deaths in the ART period in rural Uganda: a prospective cohort study, 2006-2008

Validation studies of verbal autopsy methods: a systematic review

BACKGROUND

Verbal autopsy (VA) has emerged as an increasingly popular technique to assign cause of death in parts of the world where the majority of deaths occur without proper medical certification. The purpose of this study was to examine the key characteristics of studies that have attempted to validate VA cause of death against an established cause of death.

METHODS

A systematic review was conducted by searching the MEDLINE, EMBASE, Cochrane-library, and Scopus electronic databases. Included studies contained 1) a VA component, 2) a validation component, and 3) original analysis or re-analysis. Characteristics of VA studies were extracted. A total of 527 studies were assessed, and 481 studies screened to give 66 studies selected for data extraction.

RESULTS

Sixty-six studies were included from multiple countries. Ten studies used an existing database. Sixteen studies used the World Health Organization VA questionnaire and 5 studies used the Population Health Metrics Research Consortium VA questionnaire. Physician certification was used in 36 studies and computer coded methods were used in 14 studies. Thirty-seven studies used high level comparator data with detailed laboratory investigations.

CONCLUSION

Most studies found VA to be an effective cause of death assignment method and compared VA cause of death to a high-quality established cause of death. Nonetheless, there were inconsistencies in the methodologies of the validation studies, and many used poor quality comparison cause of death data. Future VA validation studies should adhere to consistent methodological criteria so that policymakers can easily interpret the findings to select the most appropriate VA method.

PROSPERO REGISTRATION

CRD42020186886.

Reporting of ethics in peer-reviewed verbal autopsy studies: a systematic review

Introduction

Verbal autopsy (VA) is a method that determines the cause of death by interviewing a relative of the deceased about the events occurring before the death, in regions where medical certification of cause of death is incomplete. This paper aims to review the ethical standards reported in peer-reviewed VA studies.

Methods

A systematic review of Medline and Ovid was conducted by two independent researchers. Data were extracted and analysed for articles based on three key areas: Institutional Review Board (IRB) clearance and consenting process; data collection and management procedures, including: time between death and interview; training and education of interviewer, confidentiality of data and data security; and declarations of funding and conflict of interest.

Results

The review identified 802 articles, of which 288 were included. The review found that 48% all the studies reported having IRB clearance or obtaining consent of participants. The interviewer training and education levels were reported in 62% and 21% of the articles, respectively. Confidentiality of data was reported for 14% of all studies, 18% did not report the type of respondent interviewed and 51% reported time between death and the interview for the VA. Data security was reported in 8% of all studies. Funding was declared in 63% of all studies and conflict of interest in 42%. Reporting of all these variables increased over time.

Conclusions

The results of this systematic review show that although there has been an increase in ethical reporting for VA studies, there still remains a large gap in reporting.

Completeness and reliability of mortality data in Viet Nam: Implications for the national routine health management information system

Background

Mortality statistics form a crucial component of national Health Management Information Systems (HMIS). However, there are limitations in the availability and quality of mortality data at national level in Viet Nam. This study assessed the completeness of recorded deaths and the reliability of recorded causes of death (COD) in the A6 death registers in the national routine HMIS in Viet Nam.

Methodology and findings

1477 identified deaths in 2014 were reviewed in two provinces. A capture-recapture method was applied to assess the completeness of the A6 death registers. 1365 household verbal autopsy (VA) interviews were successfully conducted, and these were reviewed by physicians who assigned multiple and underlying cause of death (UCOD). These UCODs from VA were then compared with the CODs recorded in the A6 death registers, using kappa scores to assess the reliability of the A6 death register diagnoses. The overall completeness of the A6 death registers in the two provinces was 89.3% (95%CI: 87.8–90.8). No COD recorded in the A6 death registers demonstrated good reliability. There is very low reliability in recording of cardiovascular deaths (kappa for stroke = 0.47 and kappa for ischaemic heart diseases = 0.42) and diabetes (kappa = 0.33). The reporting of deaths due to road traffic accidents, HIV and some cancers are at a moderate level of reliability with kappa scores ranging between 0.57–0.69 (p<0.01). VA methods identify more specific COD than the A6 death registers, and also allow identification of multiple CODs.

Conclusions

The study results suggest that data completeness in HMIS A6 death registers in the study sample of communes was relatively high (nearly 90%), but triangulation with death records from other sources would improve the completeness of this system. Further, there is an urgent need to enhance the reliability of COD recorded in the A6 death registers, for which VA methods could be effective. Focussed consultation among stakeholders is needed to develop a suitable mechanism and process for integrating VA methods into the national routine HMIS A6 death registers in Viet Nam.

COHORT PROFILE: The Complications of Long-Term Antiretroviral Therapy study in Uganda (CoLTART), a prospective clinical cohort

BACKGROUND

Antiretroviral therapy (ART) improves the survival and quality of life of HIV-positive individuals, but the effects of long-term ART use do eventually manifest. The Complications of Long-Term Antiretroviral Therapy cohort study in Uganda (CoLTART) was established to investigate the metabolic and renal complications of long-term ART use among Ugandan adults. We describe the CoLTART study set-up, aims, objectives, study methods, and also report some preliminary cross-sectional study enrolment metabolic and renal complications data analysis results.

METHODS

HIV-positive ART naïve and experienced adults (18 years and above) in Uganda were enrolled. Data on demographic, dietary, medical, social economic and behaviour was obtained; and biophysical measurements and a clinical examination were undertaken. We measured: fasting glucose and lipid profiles, renal and liver function tests, full blood counts, immunology, virology and HIV drug resistance testing. Plasma samples were stored for future studies.

RESULTS

Between July 2013 and October 2014, we enrolled 1095 individuals, of whom 964 (88.0%) were ART experienced (6 months or more), with a median of 9.4 years (IQR 7.0-9.9) on ART. Overall, 968 (88.4%) were aged 35 years and above, 711 (64.9%) were females, 608 (59.6%) were or had ever been on a Tenofovir ART regimen and 236 (23.1%) on a Protease Inhibitor (PI) regimen. There were no differences in renal dysfunction between patients on Tenofovir and Non-Tenofovir containing ART regimens. Patients on PI regimens had higher total cholesterol, lower high density lipoprotein, higher low density lipoprotein, higher triglycerides, and a high atherogenic index for plasma than the non-PI regimen, p = 0.001 or < 0.001. Patients on Non-PI regimens had higher mean diastolic hypertension than patients on PI regimens, p < 0.001.

CONCLUSIONS

Our finding of no differences in renal dysfunction between patients on Tenofovir and those on Non-Tenofovir containing ART regimens means that Tenofovir based first line ART can safely be initiated even in settings without routine renal function monitoring. However, integration of cardiovascular risk assessment, preventive and curative measures against cardiovascular disease are required. The CoLTART cohort is a good platform to investigate the complications of long-term ART use in Uganda.

Pilot study of antibodies against varicella zoster virus and human immunodeficiency virus in relation to the risk of developing stroke, nested within a rural cohort in Uganda

OBJECTIVE

The risk of stroke rises after episodes of herpes zoster and chickenpox, which are caused by varicella zoster virus (VZV). We conducted a pilot case-control study of stroke, nested within a long-standing cohort in Uganda (the General Population Cohort), to examine antibodies against VZV prior to diagnosis.

METHODS

We used stored sera to examine the evolution of IgG and IgM antibodies against VZV among 31 clinically confirmed cases of stroke and 132 matched controls. For each participant, three samples of sera were identified: one each, taken at or near the time of (pseudo)diagnosis, between 5 and 10 years prior to diagnosis and at 15 years prior to diagnosis.

RESULTS

All participants had detectable antibodies against VZV, but there were no significant differences between cases and controls in the 15 years prior to diagnosis. As a secondary finding, 16% (5/31) of cases and 6% (8/132) of controls had HIV (OR 3.0; 95% CI 0.8-10.1; P = 0.06).

CONCLUSIONS

This is the first prospective study to examine a biological measure of exposure to VZV prior to diagnosis of stroke and although we identified no significant association, in this small pilot, with limited characterisation of cases, we cannot exclude the possibility that the virus is causal for a subset. The impact of HIV on risk of stroke has not been well characterised and warrants further study.

A comparative analysis of national HIV policies in six African countries with generalized epidemics

OBJECTIVE

To compare national human immunodeficiency virus (HIV) policies influencing access to HIV testing and treatment services in six sub-Saharan African countries.

METHODS

We reviewed HIV policies as part of a multi-country study on adult mortality in sub-Saharan Africa. A policy extraction tool was developed and used to review national HIV policy documents and guidelines published in Kenya, Malawi, South Africa, Uganda, the United Republic of Tanzania and Zimbabwe between 2003 and 2013. Key informant interviews helped to fill gaps in findings. National policies were categorized according to whether they explicitly or implicitly adhered to 54 policy indicators, identified through literature and expert reviews. We also compared the national policies with World Health Organization (WHO) guidance.

FINDINGS

There was wide variation in policies between countries; each country was progressive in some areas and not in others. Malawi was particularly advanced in promoting rapid initiation of antiretroviral therapy. However, no country had a consistently enabling policy context expected to increase access to care and prevent attrition. Countries went beyond WHO guidance in certain areas and key informants reported that practice often surpassed policy.

CONCLUSION

Evaluating the impact of policy differences on access to care and health outcomes among people living with HIV is challenging. Certain policies will exert more influence than others and official policies are not always implemented. Future research should assess the extent of policy implementation and link these findings with HIV outcomes.

Prevalence of dyslipidaemia and associated risk factors in a rural population in South-Western Uganda: a community based survey

BACKGROUND

The burden of dyslipidaemia is rising in many low income countries. However, there are few data on the prevalence of, or risk factors for, dyslipidaemia in Africa.

METHODS

In 2011, we used the WHO Stepwise approach to collect cardiovascular risk data within a general population cohort in rural south-western Uganda. Dyslipidaemia was defined by high total cholesterol (TC) ≥ 5.2 mmol/L or low high density lipoprotein cholesterol (HDL-C) <1 mmol/L in men, and <1.3 mmol/L in women. Logistic regression was used to explore correlates of dyslipidaemia.

RESULTS

Low HDL-C prevalence was 71.3% and high TC was 6.0%. In multivariate analysis, factors independently associated with low HDL-C among both men and women were: decreasing age, tribe (prevalence highest among Rwandese tribe), lower education, alcohol consumption (comparing current drinkers to never drinkers: men adjusted (a)OR=0.44, 95%CI=0.35-0.55; women aOR=0.51, 95%CI=0.41-0.64), consuming <5 servings of fruit/vegetable per day, daily vigorous physical activity (comparing those with none vs those with 5 days a week: men aOR=0.83 95%CI=0.67-1.02; women aOR=0.76, 95%CI=0.55-0.99), blood pressure (comparing those with hypertension to those with normal blood pressure: men aOR=0.57, 95%CI=0.43-0.75; women aOR=0.69, 95%CI=0.52-0.93) and HIV infection (HIV infected without ART vs. HIV negative: men aOR=2.45, 95%CI=1.53-3.94; women aOR=1.88, 95%CI=1.19-2.97). The odds of low HDL-C was also higher among men with high BMI or HbA1c ≤ 6%, and women who were single or with abdominal obesity. Among both men and women, high TC was independently associated with increasing age, non-Rwandese tribe, high waist circumference (men aOR=5.70, 95%CI=1.97-16.49; women aOR=1.58, 95%CI=1.10-2.28), hypertension (men aOR=3.49, 95%CI=1.74-7.00; women aOR=1.47, 95%CI=0.96-2.23) and HbA1c >6% (men aOR=3.00, 95%CI=1.37-6.59; women aOR=2.74, 95%CI=1.77-4.27). The odds of high TC was also higher among married men, and women with higher education or high BMI.

CONCLUSION

Low HDL-C prevalence in this relatively young rural population is high whereas high TC prevalence is low. The consequences of dyslipidaemia in African populations remain unclear and prospective follow-up is required.

Measuring child awareness for adult symptomatic HIV using a verbal assessment tool: concordance between adult-child dyads on adult HIV-associated symptoms and illnesses

OBJECTIVES

This study assessed children's awareness for adult HIV-associated symptoms and illnesses using a verbal assessment tool by analysing inter-rater reliability between adult-child dyads. This study also evaluated sociodemographic and household characteristics associated with child awareness of adult symptomatic HIV.

METHODS

A cross-sectional survey using a representative community sample of adult-child dyads (N=2477 dyads) was conducted in KwaZulu-Natal, South Africa. Analyses focused on a subsample (n=673 adult-child dyads) who completed verbal assessment interviews for symptomatic HIV. We used an existing validated verbal autopsy approach, originally designed to determine AIDS-related deaths by adult proxy reporters. We adapted this approach for use by child proxy reporters for reporting on HIV-associated symptoms and illnesses among living adults. Analyses assessed whether children could reliably report on adult HIV-associated symptoms and illnesses and adult provisional HIV status.

RESULTS

Adult-child pairs concurred above the 65th percentile for 9 of the 10 HIV-associated symptoms and illnesses with sensitivities ranging from 10% to 100% and specificities ranging from 20% to 100%. Concordant reporting between adult-child dyads for the adult's provisional HIV status was 72% (sensitivity=68%, specificity=73%). Children were more likely to reliably match adult's reports of provisional HIV status when they lived in households with more household members, and households with more robust socioeconomic indicators including access to potable water, food security and television.

CONCLUSIONS

Children demonstrate awareness of HIV-associated symptoms and illnesses experienced by adults in their household. Children in households with greater socioeconomic resources and more household members were more likely to reliably report on the adult's provisional HIV status.

Comparison of physician-certified verbal autopsy with computer-coded verbal autopsy for cause of death assignment in hospitalized patients in low- and middle-income countries: systematic review

BACKGROUND

Computer-coded verbal autopsy (CCVA) methods to assign causes of death (CODs) for medically unattended deaths have been proposed as an alternative to physician-certified verbal autopsy (PCVA). We conducted a systematic review of 19 published comparison studies (from 684 evaluated), most of which used hospital-based deaths as the reference standard. We assessed the performance of PCVA and five CCVA methods: Random Forest, Tariff, InterVA, King-Lu, and Simplified Symptom Pattern.

METHODS

The reviewed studies assessed methods' performance through various metrics: sensitivity, specificity, and chance-corrected concordance for coding individual deaths, and cause-specific mortality fraction (CSMF) error and CSMF accuracy at the population level. These results were summarized into means, medians, and ranges.

RESULTS

The 19 studies ranged from 200 to 50,000 deaths per study (total over 116,000 deaths). Sensitivity of PCVA versus hospital-assigned COD varied widely by cause, but showed consistently high specificity. PCVA and CCVA methods had an overall chance-corrected concordance of about 50% or lower, across all ages and CODs. At the population level, the relative CSMF error between PCVA and hospital-based deaths indicated good performance for most CODs. Random Forest had the best CSMF accuracy performance, followed closely by PCVA and the other CCVA methods, but with lower values for InterVA-3.

CONCLUSIONS

There is no single best-performing coding method for verbal autopsies across various studies and metrics. There is little current justification for CCVA to replace PCVA, particularly as physician diagnosis remains the worldwide standard for clinical diagnosis on live patients. Further assessments and large accessible datasets on which to train and test combinations of methods are required, particularly for rural deaths without medical attention.

Revising the WHO verbal autopsy instrument to facilitate routine cause-of-death monitoring

Objective

Verbal autopsy (VA) is a systematic approach for determining causes of death (CoD) in populations without routine medical certification. It has mainly been used in research contexts and involved relatively lengthy interviews. Our objective here is to describe the process used to shorten, simplify, and standardise the VA process to make it feasible for application on a larger scale such as in routine civil registration and vital statistics (CRVS) systems.

Methods

A literature review of existing VA instruments was undertaken. The World Health Organization (WHO) then facilitated an international consultation process to review experiences with existing VA instruments, including those from WHO, the Demographic Evaluation of Populations and their Health in Developing Countries (INDEPTH) Network, InterVA, and the Population Health Metrics Research Consortium (PHMRC). In an expert meeting, consideration was given to formulating a workable VA CoD list [with mapping to the International Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) CoD] and to the viability and utility of existing VA interview questions, with a view to undertaking systematic simplification.

Findings

A revised VA CoD list was compiled enabling mapping of all ICD-10 CoD onto 62 VA cause categories, chosen on the grounds of public health significance as well as potential for ascertainment from VA. A set of 221 indicators for inclusion in the revised VA instrument was developed on the basis of accumulated experience, with appropriate skip patterns for various population sub-groups. The duration of a VA interview was reduced by about 40% with this new approach.

Conclusions

The revised VA instrument resulting from this consultation process is presented here as a means of making it available for widespread use and evaluation. It is envisaged that this will be used in conjunction with automated models for assigning CoD from VA data, rather than involving physicians.

Animal models and conserved processes

BACKGROUND

The concept of conserved processes presents unique opportunities for using nonhuman animal models in biomedical research. However, the concept must be examined in the context that humans and nonhuman animals are evolved, complex, adaptive systems. Given that nonhuman animals are examples of living systems that are differently complex from humans, what does the existence of a conserved gene or process imply for inter-species extrapolation?

METHODS

We surveyed the literature including philosophy of science, biological complexity, conserved processes, evolutionary biology, comparative medicine, anti-neoplastic agents, inhalational anesthetics, and drug development journals in order to determine the value of nonhuman animal models when studying conserved processes.

RESULTS

Evolution through natural selection has employed components and processes both to produce the same outcomes among species but also to generate different functions and traits. Many genes and processes are conserved, but new combinations of these processes or different regulation of the genes involved in these processes have resulted in unique organisms. Further, there is a hierarchy of organization in complex living systems. At some levels, the components are simple systems that can be analyzed by mathematics or the physical sciences, while at other levels the system cannot be fully analyzed by reducing it to a physical system. The study of complex living systems must alternate between focusing on the parts and examining the intact whole organism while taking into account the connections between the two. Systems biology aims for this holism. We examined the actions of inhalational anesthetic agents and anti-neoplastic agents in order to address what the characteristics of complex living systems imply for inter-species extrapolation of traits and responses related to conserved processes.

CONCLUSION

We conclude that even the presence of conserved processes is insufficient for inter-species extrapolation when the trait or response being studied is located at higher levels of organization, is in a different module, or is influenced by other modules. However, when the examination of the conserved process occurs at the same level of organization or in the same module, and hence is subject to study solely by reductionism, then extrapolation is possible.

Human immune responses to vaccines in the first year of life: biological, socio-economic and ethical issues - a viewpoint

Human newborns are vulnerable to infectious diseases that account for majority of the morbidity and mortality, particularly in first year of life. Vaccines have become the most effective public health intervention strategy to curtail the prevalence of these infectious diseases. Although vaccines against a number of diseases exist, there are no vaccines against many other diseases that commonly affect children. The adequate assessment of immune responses to vaccines is an important step in the development of vaccines. However, a number of biological and "non-medical" socio-economic and ethical factors could influence either the administration and/or evaluation of vaccines in infants. Recognition and understanding of these determinants are crucial in planning interventions and for logical interpretations of results.