22 research outputs found
Beyond adolescents : The study of sexual behaviour of middle-aged men in Nigeria
Studies on sexual behaviour in Nigeria have rather been lopsided largely focussing on
adolescents while neglecting the older men. This may not be unconnected with the fact that the
young people are often seen as being more sexually active than the older men. In this study, the
patterns and the determinants of sexual behaviour of middle-aged men were investigated.
This study is based on secondary data analysis of the 2003 Nigeria Demographic and Health
Survey male dataset. Data collected from a sample of 633 men whose ages fall between 40 and
59 years in Nigeria were extracted and analysed to achieve the set objectives. The variables of
interest were analysed by using relevant statistical techniques with the aid of SAS enterprise
guide. Sexual behaviour was measured by three variables namely: current sexual activity, extra
marital partnership and condom use. Also, three hypotheses were tested. The Health Belief
Model (HBM) was the theoretical model used for this study.
The study shows that a high proportion of men (71.2%) aged 40-59 years in Nigeria are sexually
active. The study further reveals that about 12% of Nigerian middle-aged men engage in
extramarital sex and 30% are in polygynous relationships (i.e. have multiple sex partners) while
condom use is very low among them. Extramarital sex is more prevalent in the rural (7.05%)
than urban (4.5%) areas. The study shows that the correlates of current sexual activity among the
middle-aged men in Nigeria are education and religion while engagement in extramarital sexual
activity is determined by ethnicity, age at first intercourse and knowledge of HIV/AIDS. Among
the sexually active ones, condom use is influenced by ethnicity, marriage type and extramarital
partnership. The sexual behaviour of middle-aged men in Nigeria follows the pattern described
in the HBM. That is, individual, socio-economic and HIV/AIDS factors can influence the sexual
behaviour of Middle-aged men.
The study concludes that in addressing the problems associated with sexual and reproductive
health of Nigerian, focus should also be extended to middle-aged men, instead of the narrow
focus on only adolescents and youths. Further investigation, using multiple methods of data
collection is also suggested
A longitudinal study of migration and it relation to AIDS/TB mortality in rural South Africa
A thesis submitted to the Faculty of Humanities, University of Witwatersrand, Johannesburg, South Africa in fulfilment of the requirements of the Degree of Doctor of Philosophy in the field of Demography and Population Studies.Background: In exploring the relationship between migration and HIV/AIDS, a
focus of earlier studies was on the role of the mobile population in the
geographical spread of the disease. There has been a shift in this perception and
the focus now is on the implications of being a migrant. A body of literature
has developed on the risk of migrants contracting HIV, but only a few studies
have examined the AIDS/TB mortality risk as a consequence of migration, with
the results showing that migrants have higher chance of dying of AIDS/TB
compared to their non-migrant counterparts. However, these studies mainly
looked at the impact of migration on mortality due to AIDS/TB and did not
make provision for the presence of other causes of death. Therefore, this study
is geared towards investigating migration as it relates to death caused by
AIDS/TB, longitudinally, and in the presence of other causes such as non
communicable diseases, other infectious diseases, and external causes of death,
in rural South Africa. Specifically, the study addressed the following questions:
(i) What is the risk of dying from AIDS/TB among migrants in rural South
Africa in the presence of other causes of death? (ii) How does this relationship
compare with the relationship between migration and other causes of death? (3)
What are possible predictors of the relationship between migration and
AIDS/TB in the presence of other causes of death?
Method: This research project is part of a longitudinal study of the inhabitants
of the Agincourt sub-district, situated in the rural north-eastern part of South
Africa. The study utilises the Agincourt Health and Demographic Surveillance
System data spanning 12 years, starting from 1st January, 2000 to 31st
December, 2011. The main target group for the study is individuals aged 20 to
69 years at the date of analysis. The selected individuals are divided into the
following categories: (i) the return migrants who returned after spending a
period of time outside the study area; (ii) the in-migrants who moved into the
study location for the first time, and (iii) the permanent residents (non
migrants). A six month residence threshold period is used to distinguish
participants from ordinary visitors. The migration status categorical variable
was further expanded from three to five categories with in-migrant and return
migrant categories being split to accommodate short and long-term durations of
exposure. In the year 2000, the baseline year, a total of 25,621 individuals who
met the entry criteria were recruited into the study.
For data analysis, a Fine and Gray model is used, which is a variant of a Cox
proportional hazard model, to estimate the competing risk of dying among the
selected participants by sex. The causes of death (CoD) variable was
categorised into the following broad categories: âAIDS/TBâ, âNon
Communicable Diseaseâ, âExternal causeâ and âOther infectious diseaseâ, with
indeterminate causes coded as missing. The five categories of migration serve
as the independent variable, with permanent residence acting as the reference
group, while the broad Cause of Death categories are the main dependent
variables. Other dependent variables are: period, nationality, education and
socio-economic status.
Results: This first set of results aims to address the question on the risk of
AIDS/TB mortality among migrants in rural South Africa in the presence of
other causes of death. The findings are that male and female short-term return
migrants have significantly higher relative risk of dying of AIDS/TB death
when compared to their non-migrants counterparts with sub-hazard ratio (SHR)
of 4.87 (95% CI 4.17-5.72; P<0.001) and 5.44 (95% CI 4.64-6.38; P<0.001))
reported for both gender group respectively. For male and female long-term
return migrants, their SHR was 1.80 (95% CI 1.43-2.26; P<0.001) and 2.06
(95% CI 1.57-2.70; P<0.001) respectively. The results did not reveal significant
results for the in-migrants.
The second set of results aims to address the second research question, which
is, how does the relationship between migration and mortality caused by
AIDS/TB in rural South Africa in the context of other causes of death compare
with the relationship between migration and causes different from AIDS/TB.
The results show that Short-term return migrants have higher mortality than
non-migrants, whatever the four causes of mortality. For instance, the
competing risk of death due to AIDS/TB for short-term return migrants
compared to non-migrants showed a lower SHR for external cause of death,
namely 8.78 (95% CI 5.86-13.16; P<0.05) vis-Ă -vis non-migrants. This implies
that the difference in the relative risk of mortality between migrants and non
migrants is even higher for external causes than for AIDS/TB. The same is
applicable to the risk of death from other infectious diseases for females, which
has a SHR of 4.97 (95% CI 2.50-9.89; P<0.05) in the competing risk model.
The relative risk of death due to AIDS/TB for male is 4.87 (95% CI 4.14-5.72
P<0.001) while that of female is 5.44 (95% CI 4.64-6.38; P<0.001);
respectively.
With regards to the question on the possible predictors of the relationship
between migration and AIDS/TB in the presence of other causes of death, it is
shown that period is one of the predictors of the relationship between migration
and AIDS/TB mortality. And, it is relevant to the study participants who died
as a result of AIDS/TB, NCDs and other infectious diseases. In general, the risk
dwindles in the latter period when the antiretroviral drugs become available for
AIDS/TB. Nationality is also a determinant of the relationship and it is
applicable to those who lost their lives due AIDS/TB (female only), NCDs and
other infections (female). In all, the Mozambican nationals are less likely to die
in comparison with the South Africans. Educational status is a predictor and it
relevance cuts across virtually all the causes of death. The dominant pattern that
is revealed in this context is that the higher the level of education, the lower the
risk of death due to any of the causes. The predictive impact of SES can only be felt among the respondents whose death was due to AIDS/TB and NCDs
(female only).
Conclusion: With circular labour migration in South Africa showing no
evidence of declining and with the attendant mortality risks due to AIDS/TB
and other causes, and needs to be carefully considered - in policies aiming to
control mortality in South Africa. Disease-induced migration creates burdens
not only for the left-behind families in terms of their means of livelihood
through loss of remittances, but also for the burden on health care facilities in
the rural area. With short-term labour migrants being a high risk group, the
success of intervention programmes addressing the problem of HIV infection
and the resultant mortality implication, such as âtreatment as preventionâ
programmes, can only be guaranteed by recognising the risks incumbent on this
group of people and the influence of the larger communities.XL201
Relationship between school dropout and teen pregnancy among rural South African young women
BackgroundSexual activity may be less likely to occur during periods of school enrolment because of the structured and supervised environment provided, the education obtained and the safer peer networks encountered while enrolled. We examined whether school enrolment was associated with teen pregnancy in South Africa
Profile: Agincourt health and socio-demographic surveillance system.
The Agincourt health and socio-demographic surveillance system (HDSS), located in rural northeast South Africa close to the Mozambique border, was established in 1992 to support district health systems development led by the post-apartheid ministry of health. The HDSS (90 000 people), based on an annual update of resident status and vital events, now supports multiple investigations into the causes and consequences of complex health, population and social transitions. Observational work includes cohorts focusing on different stages along the life course, evaluation of national policy at population, household and individual levels and examination of household responses to shocks and stresses and the resulting pathways influencing health and well-being. Trials target children and adolescents, including promoting psycho-social well-being, preventing HIV transmission and reducing metabolic disease risk. Efforts to enhance the research platform include using automated measurement techniques to estimate cause of death by verbal autopsy, full 'reconciliation' of in- and out-migrations, follow-up of migrants departing the study area, recording of extra-household social connections and linkage of individual HDSS records with those from sub-district clinics. Fostering effective collaborations (including INDEPTH multi-centre work in adult health and ageing and migration and urbanization), ensuring cross-site compatibility of common variables and optimizing public access to HDSS data are priorities
Moringa oleifera ameliorates histomorphological changes associated with cuprizone neurotoxicity in the hippocampal Cornu ammonis (CA) 3 region
Summary: Cuprizone-induced neurotoxicity has severally been used to study demyelinating diseases like multiple sclerosis (MS), adversely affecting both the white and grey matters of the brain. Lesions have been observed in different regions of the brain including, corpus callosum, neocortex and the hippocampal formation. The current study explored the role of Moringa oleifera leaf extract in restoring the resultant histomorphological changes in cuprizone-induced hippocampal damage in Wistar rats. Twenty adult female Wistar rats with average weight of 163.74 ± 3.59 g were grouped into A: Control, administered with 1 ml of normal saline, B: received 0.4% cuprizone diet, C: received 1.875 mg/ml/day of Moringa extract, and D: received a combination of cuprizone and Moringa in similar doses. Administration was oral for 5 weeks. The weights of animals were assessed during treatment, and at the termination of experiment, the rats were euthanized and the brains were fixed in 4% paraformaldehyde. The tissue was processed for histological and histochemical examinations using the Haematoxylin and Eosin stain and cresyl fast violet stain to assess the general microarchitecture and neuronal cells respectively of hippocampal cornu ammonis (CA) 3 region. The body weight of cuprizone-treated rats was reduced and this was ameliorated significantly in animals that were co-administered with Moringa. Similarly, there were histological alterations in the CA3 region of the hippocampus with the presence of pyknotic pyramidal cells organized in clusters and CA3 cells with degenerative changes, but administration of Moringa led to a better organised and fairly intact histological appearance. Pharmaceutical development of Moringa oleifera into appropriate therapeutic formulations could offer some relief to patients of demyelinating conditions that have clinical features of neurological deficits.Keywords: cuprizone, neurotoxicity, hippocampus, Moring
Evidence for sample selection effect and Hawthorne effect in behavioural HIV prevention trial among young women in a rural South African community
Objectives We examined the potential influence of both sample selection effects and Hawthorne effects in the behavioural HIV Prevention Trial Network 068 study, designed to examine whether cash transfers conditional on school attendance reduce HIV acquisition in young South African women. We explored whether school enrolment among study participants differed from the underlying population, and whether differences existed at baseline (sample selection effect) or arose during study participation (Hawthorne effect). Methods We constructed a cohort of 3889 young women aged 11-20 years using data from the Agincourt Health and socio-Demographic Surveillance System. We compared school enrolment in 2011 (trial start) and 2015 (trial end) between those who did (n=1720) and did not (n=2169) enrol in the trial. To isolate the Hawthorne effect, we restricted the cohort to those enrolled in school in 2011. Results In 2011, trial participants were already more likely to be enrolled in school (99%) compared with non-participants (93%). However, this association was attenuated with covariate adjustment (adjustedârisk difference (aRD) (95%âCI): 2.9 (â 0.7 to 6.5)). Restricting to those enrolled in school in 2011, trial participants were also more likely to be enrolled in school in 2015 (aRD (95%âCI): 4.9 (1.5 to 8.3)). The strength of associations increased with age. Conclusions Trial participants across both study arms were more likely to be enrolled in school than non-participants. Our findings suggest that both sample selection and Hawthorne effects may have diminished the differences in school enrolment between study arms, a plausible explanation for the null trial findings. The Hawthorne-specific findings generate hypotheses for how to structure school retention interventions to prevent HIV
Relationship between school dropout and teen pregnancy among rural South African young women
BackgroundSexual activity may be less likely to occur during periods of school enrolment because of the structured and supervised environment provided, the education obtained and the safer peer networks encountered while enrolled. We examined whether school enrolment was associated with teen pregnancy in South Africa. MethodsUsing longitudinal demographic surveillance data from the rural Agincourt sub-district, we reconstructed the school enrolment status from 2000 through 2011 for 15 457 young women aged 12â18 years and linked them to the estimated conception date for each pregnancy during this time. We examined the effect of time-varying school enrolment on teen pregnancy using a Cox proportional hazard model, adjusting for: age; calendar year; household socioeconomic status; household size; and gender, educational attainment and employment of household head. A secondary analysis compared the incidence of pregnancy among school enrolees by calendar time: school term vs school holiday. ResultsSchool enrolment was associated with lower teen pregnancy rates [adjusted hazard ratio (95% confidence interval): 0.57 (0.50, 0.65)].This association was robust to potential misclassification of school enrolment. For those enrolled in school, pregnancy occurred less commonly during school term than during school holidays [incidence rate ratio (95% confidence interval): 0.90 (0.78, 1.04)]. ConclusionsYoung women who drop out of school may be at higher risk for teen pregnancy and could likely benefit from receipt of accessible and high quality sexual health services. Preventive interventions designed to keep young women in school or addressing the underlying causes of dropout may also help reduce the incidence of teen pregnancy
Association between internal migration and epidemic dynamics : an analysis of cause-specific mortality in Kenya and South Africa using health and demographic surveillance data
Background: Many low- and middle-income countries are facing a double burden of disease with persisting high levels of infectious disease, and an increasing prevalence of non-communicable disease (NCD). Within these settings, complex processes and transitions concerning health and population are underway, altering population dynamics and patterns of disease. Understanding the mechanisms through which changing socioeconomic and environmental contexts may influence health is central to developing appropriate public health policy. Migration, which involves a change in environment and health exposure, is one such mechanism. Methods: This study uses Competing Risk Models to examine the relationship between internal migration and premature mortality from AIDS/TB and NCDs. The analysis employs 9 to 14 years of longitudinal data from four Health and Demographic Surveillance Systems (HDSS) of the INDEPTH Network located in Kenya and South Africa (populations ranging from 71 to 223 thousand). The study tests whether the mortality of migrants converges to that of non-migrants over the period of observation, controlling for age, sex and education level. Results: In all four HDSS, AIDS/TB has a strong influence on overall deaths. However, in all sites the probability of premature death (45q15) due to AIDS/TB is declining in recent periods, having exceeded 0.39 in the South African sites and 0.18 in the Kenyan sites in earlier years. In general, the migration effect presents similar patterns in relation to both AIDS/TB and NCD mortality, and shows a migrant mortality disadvantage with no convergence between migrants and non-migrants over the period of observation. Return migrants to the Agincourt HDSS (South Africa) are on average four times more likely to die of AIDS/TB or NCDs than are non-migrants. In the Africa Health Research Institute (South Africa) female return migrants have approximately twice the risk of dying from AIDS/TB from the year 2004 onwards, while there is a divergence to higher AIDS/TB mortality risk amongst female migrants to the Nairobi HDSS from 2010. Conclusion: Results suggest that structural socioeconomic issues, rather than epidemic dynamics are likely to be associated with differences in mortality risk by migrant status. Interventions aimed at improving recent migrant's access to treatment may mitigate risk.Errata: Ginsburg, C., Bocquier, P., BĂ©guy, D. et al. Correction to: association between internal migration and epidemic dynamics: an analysis of cause-specific mortality in Kenya and South Africa using health and demographic surveillance data. BMC Public Health 21, 1555 (2021). DOI: 10.1186/s12889-021-11604-z</p
Human capital on the move: Education as a determinant of internal migration in selected INDEPTH surveillance populations in Africa
Background: Education, as a key indicator of human capital, is considered one of the major determinants of internal migration, with previous studies suggesting that human capital accumulates in urban areas at the expense of rural areas. However, there is fragmentary evidence concerning the educational correlates of internal migration in sub-Saharan Africa. Objective: The study questions whether more precise measures of migration in Health and Demographic Surveillance System (HDSS) populations support the hypothesis that migrants are self-selected on human capital and more educated people are more likely to leave rural areas or enter urban areas within a geographical region. Methods: Using unique longitudinal data representing approximately 900,000 people living in eight sub-Saharan African HDSS sites that are members of the INDEPTH Network, the paper uses Event History Analysis techniques to examine the relationship between formal educational attainment and in- and out-migration, over the period 2009 to 2011. Results: Between 7Ć and 27Ć of these local populations are moving in or out of the HDSS area over this period. Education is positively associated with both in- and out-migration in the Kenyan HDSS areas; however, the education effect has no clear pattern in the HDSS sites in Burkina Faso, Mozambique, and South Africa. Conclusions: Empirical results presented in this paper confirm a strong age profile of migration consistent with human capital expectation, yet the results point to variability in the association of education and the propensity to migrate. In particular, the hypothesis of a shift of human capital from rural to urban areas is not universally valid
Evidence for sample selection effect and Hawthorne effect in behavioural HIV prevention trial among young women in a rural South African community
Objectives: We examined the potential influence of both sample selection effects and Hawthorne effects in the behavioural HIV Prevention Trial Network 068 study, designed to examine whether cash transfers conditional on school attendance reduce HIV acquisition in young South African women. We explored whether school enrolment among study participants differed from the underlying population, and whether differences existed at baseline (sample selection effect) or arose during study participation (Hawthorne effect). Methods: We constructed a cohort of 3889 young women aged 11-20 years using data from the Agincourt Health and socio-Demographic Surveillance System. We compared school enrolment in 2011 (trial start) and 2015 (trial end) between those who did (n=1720) and did not (11=2169) enrol in the trial. To isolate the Hawthorne effect, we restricted the cohort to those enrolled in school in 2011. Results: In 2011, trial participants were already more likely to be enrolled in school (99%) compared with non-participants (93%). However, this association was attenuated with covariate adjustment (adjusted risk difference (aRD) (95% Cl): 2.9 (0.7 to 6.5)). Restricting to those enrolled in school in 2011, trial participants were also more likely to be enrolled in school in 2015 (aRD (95% Cl): 4.9 (1.5 to 8.3)). The strength of associations increased with age. Conclusions: Trial participants across both study arms were more likely to be enrolled in school than nonparticipants. Our findings suggest that both sample selection and Hawthorne effects may have diminished the differences in school enrolment between study arms, a plausible explanation for the null trial findings. The Hawthorne-specific findings generate hypotheses for how to structure school retention interventions to prevent HIV