Early childbearing, human capital attainment and mortality risk

This paper uses a rich longitudinal dataset to examine the relationship between teen fertility and both subsequent educational outcomes and mortality risk in rural South Africa. Human capital deficits among teen mothers are large and significant, with earlier births associated with greater deficits. In contrast to many other studies, we find no clear evidence of selectivity into teen childbearing in either schooling trajectories or pre-fertility household characteristics. Enrolment rates among teen mothers only begin to drop in the period immediately preceding the birth and future teen mothers are not behind in their schooling relative to other girls. Older teen mothers and those further ahead in school for their age pre-birth are more likely to continue schooling after the birth. Following women over a six year period we document a higher mortality risk before the age of 30 for teen mothers that cannot be explained by household characteristics in early adulthood.

Old Age Health and HIV in a Rural Area with High HIV Prevalence and Incidence: What is the Impact of Enhanced Access to Antiretroviral Treatment?

The widespread roll-out of antiretroviral therapy (ART) has resulted in a decline of HIV-related deaths; as a result the HIV positive population is rapidly ageing with improved survival of HIV positive adults on ART. In sub-Saharan Africa, including South Africa, where older adults comprise a significant proportion of the total population, health services face the complexities of an ageing population and HIV. The aim of this PhD study is to inform understanding of issues relating to older adults, aged 50 years or more, HIV infection and ART, who are resident in Northern KwaZulu-Natal, South Africa. Data from the cross-sectional Wellbeing of Older People Study (WOPS), including 422 older adults and nested within the demographic surveillance system, show that HIV positive older adults receiving ART for >1 year had less chronic morbidity than HIV negative older adults despite having higher IL6 and hsCRP levels. To quantify the cause-specific morbidity burden at the time of initiating ART, data on 1 409 adults aged ≥16 years obtained from the ART Clinical Cohort show that chronic morbidity at time of ART initiation burden and HIV-associated morbidity was more common in older than younger (16-49 years old) adults. Data from the HIV Treatment and Care programme, linked to an electronic Hospital Information database (n=8598 adults aged ≥16 years) show that older adults had a lower hospitalisation rate, but higher case fatality rates, than younger adults. In the HIV treatment and Care programme, including 8846 overall, in the first year of ART, mortality was higher in older than younger adults, but rates in the two groups were similar thereafter. Older adults had a blunted immunological but superior virological response. All-cause mortality risk increased with a decline in CD4 cell count and unsuppressed viral load. Further detailed data from the ART Clinical Cohort showed that, in both age groups, the contribution of multiple co-morbidity to early mortality was high. The results presented here contribute towards evidence required to understand issues surrounding the health of older adults in the context of high HIV prevalence and incidence with widespread availability and access to ART and provide knowledge required for evidence-based health planning for the ageing HIV cohort. The thesis concludes with a discussion of the implications for health service development and future research

Comparison of Research Ethics Committees (RECs) review of protocols reviewed by multiple ethics review committees.

Master Social Science in Psychology. University of KwaZulu-Natal, Pietermaritzburg 2016.As high-impact diseases have increased, so have the collaborative efforts to alleviate their effects. These collaborative efforts have gone beyond borders, resulting in collaborative research between low- and middle-income countries (LMICs) and high-income countries (HICs). This collaborating factor has resulted in protocol review between the sponsor and host countries, resulting in multiple ethics review of a single site protocol. This study discusses the issue of using a multiple research ethics committee (REC) model in ethics review. The study objectives were to investigate the similarity and/or variability in ethics review for a single-site protocol reviewed by multiple research ethics committees and to determine if protocols reviewed by both developing and developed countries were reviewed according to the ethical framework for clinical research proposed by Emanuel, Wendler, Killen, and Grady (2004). The study employed an exploratory qualitative design. For data collection, retrospective document review was used to review and compare REC responses. Key findings were that there are major similarities in the ethics review process of RECs in developed and developing countries. Where variability was noted, this was negligible. The study highlighted that RECs in both developed and developing countries followed common research ethics principles and benchmarks as laid out in the ethical framework by Emanuel et al. Most researchers did not deviate from the protocols when carrying out their proposed studies as determined in the subsequent publishing of results

Burden and determinants of Bacterial vaginosis in sexually active women aged 18 years and over, enrolled in an HIV prevention trial, in northern KwaZulu Natal

M.Sc (Med.), Faculty of Health Sciences, University of the Witwatersrand, 2009Background: Bacterial vaginosis (BV) results from a shift in normal vaginal flora and predisposes women to sexually transmitted infections (STI) including HIV. Risk factors for BV are not well understood. This analysis seeks to determine the disease frequency of BV, assess determinants of BV and quantify time to first BV episode in HIV negative women. Methods: Baseline and follow-up data from 1066 women was analysed in STATA10. Logistic regression was used to determine baseline factors associated with BV and Kaplan Meier survival analysis to estimate time to BV episode. Results: BV prevalence and incidence was estimated at 48.42% and 81 cases per 100 women years respectively. Controlling for age and education, women with Trichomonas vaginalis, Chlamydia trachomatis, Herpes Simplex Virus2 and lower socio-economic status were 67%- 380%, 31%-472%, 20%-220% and 4%-91% more likely to present with BV respectively. Consistent condom use and being a housewife or student was significantly (p<0.05) associated with lower prevalent BV, with a significant interaction between age and education (p<0.05). The median time to first BV episode was 9.7 months. Conclusion: The analysis identifies modifiable risk factors like condom use, injectable contraceptives and treatment of STIs which could potentially decrease the high BV disease burden

Regression Discontinuity Designs in Epidemiology: Causal Inference Without Randomized Trials

When patients receive an intervention based on whether they score below or above some threshold value on a continuously measured random variable, the intervention will be randomly assigned for patients close to the threshold. The regression discontinuity design exploits this fact to estimate causal treatment effects. In spite of its recent proliferation in economics, the regression discontinuity design has not been widely adopted in epidemiology. We describe regression discontinuity, its implementation, and the assumptions required for causal inference. We show that regression discontinuity is generalizable to the survival and nonlinear models that are mainstays of epidemiologic analysis. We then present an application of regression discontinuity to the much-debated epidemiologic question of when to start HIV patients on antiretroviral therapy. Using data from a large South African cohort (2007–2011), we estimate the causal effect of early versus deferred treatment eligibility on mortality. Patients whose first CD4 count was just below the 200 cells/μL CD4 count threshold had a 35% lower hazard of death (hazard ratio = 0.65 [95% confidence interval = 0.45–0.94]) than patients presenting with CD4 counts just above the threshold. We close by discussing the strengths and limitations of regression discontinuity designs for epidemiology

Assessing the validity of respondents’ reports of their partners’ ages in a rural South African population-based cohort

Objectives: This study evaluated the validity of using respondents’ reports of age disparity in their sexual relationships (perceived disparity), compared to age disparity based on each partner's report of their own date of birth (actual disparity). Setting: The study was conducted using data from a longitudinal population-based cohort in rural KwaZulu-Natal, South Africa, between 2005 and 2012. Participants: The study used 13 831 reports of partner age disparity within 7337 unique conjugal relationships. 10 012 (72.4%) reports were made by women. Primary and secondary outcome measures The primary outcome was the Lin concordance correlation of perceived and actual age disparities. Secondary outcomes included the sensitivity/specificity of perceived disparities to assess whether the man in the relationship was more than five or more than 10 years older than the woman. Results: Mean relationship age disparity was 6 years. On average, respondents slightly underestimated their partners’ ages (male respondents: 0.50 years; female respondents: 0.85 years). Almost three-quarters (72.3%) of age disparity estimates fell within 2 years of the true values, although a small minority of reports were far from correct. The Lin concordance correlation of perceived and actual age disparities (men: ρ=0.61; women: ρ=0.78), and assessments of whether the man in the relationship was more than five, or more than 10 years older than the woman (sensitivity >60%; specificity >75%), were relatively high. Accuracy was higher for spouses and people living in the same household, but was not affected by relationship duration. Conclusions: Rural South Africans reported their sexual partners’ ages imperfectly, but with less error than in some other African settings. Further research is required to determine how generalisable these findings are. Self-reported data on age disparity in sexual relationships can be used with caution for research, intervention design, and targeting in this and similar settings

The impact of self-interviews on response patterns for sensitive topics: a randomized trial of electronic delivery methods for a sexual behaviour questionnaire in rural South Africa

Background: Self-interviews, where the respondent rather than the interviewer enters answers to questions, have been proposed as a way to reduce social desirability bias associated with interviewer-led interviews. Computer-assisted self-interviews (CASI) are commonly proposed since the computer programme can guide respondents; however they require both language and computer literacy. We evaluated the feasibility and acceptability of using electronic methods to administer quantitative sexual behaviour questionnaires in the Somkhele demographic surveillance area (DSA) in rural KwaZulu-Natal, South Africa. Methods: We conducted a four-arm randomized trial of paper-and-pen-interview, computer-assisted personal-interview (CAPI), CASI and audio-CASI with an age-sex-urbanicity stratified sample of 504 adults resident in the DSA in 2015. We compared respondents’ answers to their responses to the same questions in previous surveillance rounds. We also conducted 48 cognitive interviews, dual-coding responses using the Framework approach. Results: Three hundred forty (67%) individuals were interviewed and covariates and participation rates were balanced across arms. CASI and audio-CASI were significantly slower than interviewer-led interviews. Item non-response rates were higher in self-interview arms. In single-paper meta-analysis, self-interviewed individuals reported more socially undesirable sexual behaviours. Cognitive interviews found high acceptance of both self-interviews and the use of electronic methods, with some concerns that self-interview methods required more participant effort and literacy. Conclusions: Electronic data collection methods, including self-interview methods, proved feasible and acceptable for completing quantitative sexual behaviour questionnaires in a poor, rural South African setting. However, each method had both benefits and costs, and the choice of method should be based on context-specific criteria

Preventing Unintended Pregnancy and HIV Transmission: Effects of the HIV Treatment Cascade on Contraceptive Use and Choice in Rural KwaZulu-Natal

Background: For women living with HIV, contraception using condoms is recommended because it prevents not only unintended pregnancy but also acquisition of other sexually transmitted infections and onward transmission of HIV. Dual-method dual-protection contraception (condoms with other contraceptive methods) is preferable over single-method dual-protection contraception (condoms alone) because of its higher contraceptive effectiveness. We estimate the effect of progression through the HIV treatment cascade on contraceptive use and choice among HIV-infected women in rural South Africa. Methods: We linked population-based surveillance data on contraception collected by the Wellcome Trust Africa Centre for Health and Population Studies to data from the local antiretroviral treatment (ART) program in Hlabisa subdistrict, KwaZulu-Natal. In bivariate probit regression, we estimated the effects of progressing through the cascade on contraceptive choice among HIV-infected sexually active women aged 15–49 years (N = 3169), controlling for a wide range of potential confounders. Findings: Contraception use increased across the cascade from 70% among women who have been on ART for 4–7 years. Holding other factors equal (1) awareness of HIV status, (2) ART initiation, and (3) being on ART for 4–7 years increased the likelihood of single-method/dual-method dual protection by the following percentage points (pp), compared with women who were unaware of their HIV status: (1) 4.6 pp (P = 0.030)/3.5 pp (P = 0.001), (2) 10.3 pp (P = 0.003)/5.2 pp (P = 0.007), and (3) 21.6 pp (P < 0.001)/11.2 pp (P < 0.001). Conclusions: Progression through the HIV treatment cascade significantly increased the likelihood of contraception in general and contraception with condoms in particular. ART programs are likely to contribute to HIV prevention through the behavioral pathway of changing contraception use and choice

The tuberculosis challenge in a rural South African HIV programme.

BACKGROUND: South Africa remains the country with the greatest burden of HIV-infected individuals and the second highest estimated TB incidence per capita worldwide. Within South Africa, KwaZulu-Natal has one of the highest rates of TB incidence and an emerging epidemic of drug-resistant tuberculosis. METHODS: Review of records of consecutive HIV-infected people initiated onto ART between 1st January 2005 and 31st March 2006. Patients were screened for TB at initiation and incident episodes recorded. CD4 counts, viral loads and follow-up status were recorded; data was censored on 5th August 2008. Geographic cluster analysis was performed using spatial scanning. RESULTS: 801 patients were initiated. TB prevalence was 25.3%, associated with lower CD4 (AHR 2.61 p = 0.01 for CD4 25 copies/ml (OR 1.75 p = 0.11). A low-risk cluster for incident TB was identified for patients living near the local hospital in the geospatial analysis. CONCLUSION: There is a large burden of TB in this population. Rate of incident TB stabilises at a rate higher than that of the overall population. These data highlight the need for greater research on strategies for active case finding in rural settings and the need to focus on strengthening primary health care

List randomization for eliciting HIV status and sexual behaviors in rural KwaZulu-Natal, South Africa: a randomized experiment using known true values for validation

Background: List randomization (LR), a survey method intended to mitigate biases related to sensitive true/false questions, has received recent attention from researchers. However, tests of its validity are limited, with no study comparing LR-elicited results with individually known truths. We conducted a test of LR for HIV-related responses in a high HIV prevalence setting in KwaZulu-Natal. By using researcher-known HIV serostatus and HIV test refusal data, we were able to assess how LR and direct questionnaires perform against individual known truth. Methods: Participants were recruited from the participation list from the 2016 round of the Africa Health Research Institute demographic surveillance system, oversampling individuals who were HIV positive. Participants were randomized to two study arms. In Arm A, participants were presented five true/false statements, one of which was the sensitive item, the others non-sensitive. Participants were then asked how many of the five statements they believed were true. In Arm B, participants were asked about each statement individually. LR estimates used data from both arms, while direct estimates were generated from Arm B alone. We compared elicited responses to HIV testing and serostatus data collected through the demographic surveillance system. Results: We enrolled 483 participants, 262 (54%) were randomly assigned to Arm A, and 221 (46%) to Arm B. LR estimated 56% (95% CI: 40 to 72%) of the population to be HIV-negative, compared to 47% (95% CI: 39 to 54%) using direct estimates; the population-estimate of the true value was 32% (95% CI: 28 to 36%). LR estimates yielded HIV test refusal percentages of 55% (95% CI: 37 to 73%) compared to 13% (95% CI: 8 to 17%) by direct estimation, and 15% (95% CI: 12 to 18%) based on observed past behavior. Conclusions: In this context, LR performed poorly when compared to known truth, and did not improve estimates over direct questioning methods when comparing with known truth. These results may reflect difficulties in implementation or comprehension of the LR approach, which is inherently complex. Adjustments to delivery procedures may improve LR’s usefulness. Further investigation of the cognitive processes of participants in answering LR surveys is warranted