Geographic assessment of access to health care in patients with cardiovascular disease in South Africa

Vascular medicine in the 21st century: Embracing comprehensive vasculature evaluation and multidisciplinary treatment

The field of vascular medicine has undergone a profound transformation in the 21^st century, transforming our approach to assessment and treatment. Atherosclerosis, a complex inflammatory disease that affects medium and large arteries, presents a major challenge for researchers and healthcare professionals. This condition, characterized by arterial plaque formation and narrowing, poses substantial challenges to vascular health at individual, national, and global scales. Its repercussions are far-reaching, with clinical outcomes including ischemic heart disease, ischemic stroke, and peripheral arterial disease—conditions with escalating global prevalence. Early detection of vascular changes caused by atherosclerosis is crucial in preventing these conditions, reducing morbidity, and averting mortality. This article underscored the imperative of adopting a holistic approach to grappling with the intricacies, trajectories, and ramifications of atherosclerosis. It stresses the need for a thorough evaluation of the vasculature and the implementation of a multidisciplinary treatment approach. By considering the entire vascular system, healthcare providers can explore avenues for prevention, early detection, and effective management of this condition, ultimately leading to improved patient outcomes. We discussed current practices and proposed new directions made possible by emerging diagnostic modalities and treatment strategies. Additionally, we considered healthcare expenditure, resource allocation, and the transformative potential of new innovative treatments and technologies.

Cross-municipality migration and spread of tuberculosis in South Africa

Human migration facilitates the spread of infectious disease. However, little is known about the contribution of migration to the spread of tuberculosis in South Africa. We analyzed longitudinal data on all tuberculosis test results recorded by South Africa's National Health Laboratory Service (NHLS), January 2011-July 2017, alongside municipality-level migration flows estimated from the 2016 South African Community Survey. We first assessed migration patterns in people with laboratory-diagnosed tuberculosis and analyzed demographic predictors. We then quantified the impact of cross-municipality migration on tuberculosis incidence in municipality-level regression models. The NHLS database included 921,888 patients with multiple clinic visits with TB tests. Of these, 147,513 (16%) had tests in different municipalities. The median (IQR) distance travelled was 304 (163 to 536) km. Migration was most common at ages 20-39 years and rates were similar for men and women. In municipality-level regression models, each 1% increase in migration-adjusted tuberculosis prevalence was associated with a 0.47% (95% CI: 0.03% to 0.90%) increase in the incidence of drug-susceptible tuberculosis two years later, even after controlling for baseline prevalence. Similar results were found for rifampicin-resistant tuberculosis. Accounting for migration improved our ability to predict future incidence of tuberculosis.

A quantitative comparison of essential cardiovascular medicines from countries in the Southern African Development Community to the WHO model essential medicines list

BACKGROUND

Globally, cardiovascular disease (CVD) is a leading cause of death and disproportionately affects low- and middle-income countries (LMICs). The WHO Model List of Essential Medicines (WHO EML) is a tool for improving accessibility and availability of medicines. This study compared the 2021 WHO EML CVDs basket of medicines with latest available national essential medicines list (NEMLs) for South Africa and 15 Southern African Development Community (SADC) countries to assess consistency in CVDs medicine listing.

METHODS

This descriptive, desktop review study compared SADC NEMLs. A comparator list was extracted by combining cardiovascular medicines listed in the 2021 WHO EML for adults and children. SADC country NEMLs were obtained from the WHO Essential Medicines and Health Products Information Portal. Consistency of NEMLs was calculated as a percentage coverage of CVD medicines listed in the 2021 WHO EML. SA hospital and primary health care (PHC) level NEMLs were included as separate formularies.

RESULTS

The SA hospital level NEML scored 70% consistency with the 2021 WHO EML. Tanzania (84%), Namibia (81%) and Angola (79%) scored the highest consistency. The mean consistency for SADC NEMLs was 66%. The lowest scoring country was Eswatini at 26%. The SA PHC NEML scored 35%. The least listed medicines were beta-blockers, angiotensin receptor blockers (ARBs), clopidogrel (43%) and paediatric formulations (furosemide (21%); digoxin (43%)). Individual antihypertensive medicines were most commonly listed. Botswana and Lesotho were the only countries to list a single pill combination (SPC) for the treatment of hypertension.

CONCLUSIONS

This comparison indicates that South Africa and most SADC countries are aligned with 2021 WHO EML recommendations. The inclusion of age-appropriate formulations for children as well as ARBs and SPC for the treatment of hypertension may improve patient adherence and cardiovascular outcomes in these countries. More frequent updates to NEMLs should improve consistency. NEMLs were not available for two countries, and these therefore did not form part of this study. Country health expenditure in ranking the consistency of NEMLs was not accounted for. LMICs adopting the essential medicine list strategy should consider imposing minimum consistency thresholds to the WHO EML to improve accessibility and availability of CVD medicines.

TRIAL REGISTRATION

Not applicable.

Prognostic values of modifiable risk factors for cardiovascular events in South African health promotion

Background

Cardiovascular diseases (CVDs) are increasing at an alarming rate among the South African population. This study aimed to determine the prognostic value of modifiable CVD risk factors for fatal and non-fatal events to inform cardiovascular health promotion practices in the South African public health system.

Methods

Data was collected from individuals participating in the South African leg of a multi-national prospective cohort study. Binary logistic regression was applied to estimate odds of total, non-fatal and fatal cardiovascular events.

Results

Binary logistic regression analyses identified age as a predictor of non-fatal and fatal CV events, with ORs of 1.87 to 3.21, respectively. Hypertension increased the odd of suffering a non-fatal CV event by almost two and a half (OR = 2.47; 95% CI = 1.26, 4.85). Moreover, being physically active reduced the odd of non-fatal CVD events by 38% (OR = 0.62; 95% CI = 0.46, 0.83 for 1 Standard deviation increase of the weighted physical activity index score (WPA)). On the one hand, gamma-glutamyltransferase (GGT) was associated with a higher fatal cardiovascular disease risk OR = 2.45 (95% CI = 1.36, 4.42) for a standard deviation increase.

Conclusions

Elevated blood pressure, GGT, and physical activity have significant prognostic values for fatal or non-fatal CV events. These findings emphasise the importance of highlighting hypertension and physical activity when planning cardiovascular health education and intervention programmes for this population, with attention to the monitoring of GGT.

Evaluating the geographic distribution of cervical cancer patients presenting to a multidisciplinary gynecologic oncology clinic in Gaborone, Botswana

OBJECTIVE

In Botswana, cervical cancer is the leading cause of cancer death for females. With limited resources, Botswana is challenged to ensure equitable access to advanced cancer care. Botswana's capital city, Gaborone, houses the only gynecologic oncology multi-disciplinary team (MDT) and the one chemoradiation facility in the country. We aimed to identify areas where fewer women were presenting to the MDT clinic for care.

METHODS

This cross-sectional study examined cervical cancer patients presenting to the MDT clinic between January 2015 and March 2020. Patients were geocoded to residential sub-districts to estimate age-standardized presentation rates. Global Moran's I and Anselin Local Moran's I tested the null hypothesis that presentation rates occurred randomly in Botswana. Community- and individual-level factors of patients living in sub-districts identified with higher (HH) and lower (LL) clusters of presentation rates were examined using ordinary least squares with a spatial weights matrix and multivariable logistic regression, respectively, with α level 0.05.

RESULTS

We studied 990 patients aged 22-95 (mean: 50.6). Presentation rates were found to be geographically clustered across the country (p = 0.01). Five sub-districts were identified as clusters, two high (HH) sub-district clusters and three low (LL) sub-district clusters (mean presentation rate: 35.5 and 11.3, respectively). Presentation rates decreased with increased travel distance (p = 0.033). Patients residing in LL sub-districts more often reported abnormal vaginal bleeding (aOR: 5.62, 95% CI: 1.31-24.15) compared to patients not residing in LL sub-districts. Patients in HH sub-districts were less likely to be living with HIV (aOR: 0.59; 95% CI: 0.38-0.90) and more likely to present with late-stage cancer (aOR: 1.78; 95%CI: 1.20-2.63) compared to patients not in HH sub-districts.

CONCLUSIONS

This study identified geographic clustering of cervical cancer patients presenting for care in Botswana and highlighted sub-districts with disproportionately lower presentation rates. Identified community- and individual level-factors associated with low presentation rates can inform strategies aimed at improving equitable access to cervical cancer care.

Comparing absolute and relative distance and time travel measures of geographic access to healthcare facilities in rural Haiti

INTRODUCTION

While travel distance and time are important proxies of physical access to health facilities, obtaining valid measures with an appropriate modelling method remains challenging in many settings. We compared five measures of geographic accessibility in Haiti, producing recommendations that consider available analytic resources and geospatial goals.

METHODS

Eight public hospitals within the ministry of public health and population were included. We estimated distance and time between hospitals and geographic centroids of Haiti's section communes and population-level accessibility. Geographic feature data were obtained from public administrative databases, academic research databases and government satellites. We used validated geographic information system methods to produce five geographic access measures: (1) Euclidean distance (ED), (2) network distance (ND), (3) network travel time (NTT), (4) AccessMod 5 (AM5) distance (AM5D) and (5) AM5 travel time (AM5TT). Relative ranking of section communes across the measures was assessed using Pearson correlation coefficients, while mean differences were assessed using analysis of variance (ANOVA) and pairwise t-tests.

RESULTS

All five geographic access measures were highly correlated (range: 0.78-0.99). Of the distance measures, ED values were consistently the shortest, followed by AM5D values, while ND values were the longest. ND values were as high as 2.3 times ED values. NTT models generally produced longer travel time estimates compared with AM5TT models. ED consistently overestimated population coverage within a given threshold compared with ND and AM5D. For example, population-level accessibility within 15 km of the nearest studied hospital in the Center department was estimated at 68% for ED, 50% for AM5D and 34% for ND.

CONCLUSION

While the access measures were highly correlated, there were significant differences in the absolute measures. Consideration of the benefits and limitations of each geospatial measure together with the intended purpose of the estimates, such as relative proximity of patients or service coverage, are key to guiding appropriate use.

Toward Equitable Access to Tertiary Cancer Care in Rwanda: A Geospatial Analysis

PURPOSE

Geographic access to care is an important measure of health equity. In this study, we describe geographic access to cancer care centers (CCCs) in Rwanda with the current facilities providing care and examine how access could change with expanded care infrastructure.

METHODS

Health facilities included are public hospitals administered by the Rwanda Ministry of Health. The WorldPop Project was used to estimate population distribution, and OpenStreetMap was used to determine travel routes. On the basis of geolocations of the facilities, AccessMod 5 was used to estimate the percentage of the population that live within 1 hour, 2 hours, and 4 hours of CCCs under the current (two facilities) and expanded care (seven facilities) scenarios. Variations in access by region, poverty, and level of urbanization were described.

RESULTS

Currently, 13%, 41%, and 85% of Rwandans can access CCCs within one, two, and 4 hours of travel, respectively. With expansion of CCCs to seven facilities, access increases to 37%, 84%, and 99%, respectively. There is a substantial variation in current geographic access by province, with 1-hour access in Kigali at 98%, whereas access in the Western Province is 0%; care expansion could increase 2-hour access in the Western Province from 1% to 71%. Variation in access is also seen across the level of urbanization, with current 1-hour access in urban versus rural areas of 45% and 8%, respectively. Expanded care results in improvement of 1-hour access to 67% and 33%, respectively. Similar trends were also noted across poverty levels.

CONCLUSION

Geographical access to CCCs varies substantially by province, level of urbanization, and poverty. These disparities can be alleviated by strategic care expansion to other tertiary care facilities across Rwanda.

Rural Transportation Infrastructure in Low- and Middle-Income Countries: A Review of Impacts, Implications, and Interventions

The rural transport infrastructure sector is a critical force for sustainable development that is interwoven with many other sectors. Rural transportation is an underlying driver of many of the Sustainable Development Goals (SDGs) and a crucial contributor to many socioeconomic benefits for rural people around the world. This review paper expands upon, enhances, and cross-references the perspectives outlined in previous rural infrastructure-focused review papers. Firstly, this work gives a thorough look into the progress of the rural transportation sector in recent years by focusing on the thematic relationships between infrastructure and other components of sustainable development, namely, economics and agriculture, policy and governance, health, gender, education, and climate change and the environment. Secondly, several strategies, approaches, and tools employed by governments and practitioners within the rural transport sector are analyzed and discussed for their contributions to the wellbeing of rural dwellers in low- and middle-income countries (LMICs). These include rural roads, bridges, maintenance, and non-infrastructural approaches that include concepts such as advanced technological innovations, intermediate modes of transport (IMTs), and transport services. This paper concludes that enhancement, improvement, and extension of rural transportation infrastructure brings significant benefits to rural dwellers. However, this paper also calls for additional integration of the sector and increased usage of systems approaches that view rural transport as an active part of many other sectors and a key leverage point within rural development as a whole. Further, this paper notes areas for future research and investigation, including increased investigation of the relationship between rural transportation infrastructure and education, improved data collection and management in support of improved policymaking, improved prioritization of interventions and institutionalization of maintenance, and expansion of pro-poor transportation strategies and interventions.

Examining social determinants of undiagnosed diabetes in Namibia and South Africa using a behavioral model of health services use

AIMS

To examine factors associated with undiagnosed diabetes in Namibia and South Africa.

METHODS

This study used the most recent Demographic and Health Surveys (DHS) from Namibia (2013) and South Africa (2016). This study focused on adults at 35-64 years old. Using Andersen's Behavioral Model, potential contributing factors were categorized into predisposing factors (sex and education), enabling factors (wealth, health insurance, and residence), and a need factor (age, BMI, and high blood pressure). Separate multivariable logistic regression models were used to examine factors associated with undiagnosed diabetes in Namibia (N = 242) and South Africa (N = 525).

RESULTS

In Namibia, higher odds of having undiagnosed diabetes were associated with rural residence (adjusted odds ratio (aOR) = 2.21) and age younger than 45 years old (aOR = 3.20). In South Africa, odds of having undiagnosed diabetes were higher among the poorest-to-poorer group than it was in the richer-to-richest group (aOR = 2.33). In both countries, having high blood pressure was associated with lower odds of having undiagnosed diabetes (aOR = 0.31 in Namibia; aOR = 0.21 in South Africa).

DISCUSSION

Different enabling and need factors were associated with undiagnosed diabetes in these two countries, which implies potentially-different mechanisms driving the high prevalence of undiagnosed diabetes, as well as the needs for different solutions.

Medicines Availability among Hypertensive Patients in Primary Health Care Facilities in a Rural Province in South Africa: Findings and Implications

Objective:

Controlling blood pressure (BP) in hypertensive patients is a challenge, with the lack of antihypertensive medicines negatively impacting on BP control. Consequently, we assessed the availability of prescribed antihypertensives among patients with chronic hypertension attending primary health care (PHC) facilities in a rural province of South Africa and explored any association between medicines availability, the number of prescribed antihypertensive medicines and BP control.

Methods:

Secondary data that included patients' demographics, BP, and data on medicines availability of the intervention group from a 3 months' operational study conducted in rural PHC facilities in South Africa were analyzed. The association between medicines availability, the number of antihypertensive medicines, and BP control was explored.

Findings:

Fifty-five African patients (89.1% females) with a mean age of 61.3 years were included. Two-thirds (67.2%) received all their medicines during their monthly visits, 25.5% received some, and for 7.3%, there was no record of whether medicines were dispensed or not. Patients with controlled BP (60.0%) were more likely to have been prescribed only one antihypertensive medicine compared to patients with uncontrolled BP (20.7%) (P = 0.017; odds ratio: 5.75; 95% confidence interval: 1.46, 22.61).

Conclusion:

It is concerning that one-third of patients went home without all of their antihypertensive medicines from PHC facilities in this Province of South Africa where there is evidence of use of herbal medicines and uncontrolled BP contributing to high morbidity and mortality from cardiovascular diseases. Additional studies are needed to fully explore the association between medicines availability, their use, and BP control among patients.

Place and health infrastructure in the Gulf Cooperation Council: A systematic scoping review of GIS applications in health

The rising burden of non-communicable diseases is taxing health systems globally. Using data science and information systems is necessary to support public health practices. Geographic Information Systems (GIS) are key to inform and help guide public health policies related to place (i.e. location or where one lives) and how it affects health. Despite the increasing use of GIS for public health globally, its applications to health in the Gulf Cooperation Council (GCC) states remains largely unknown. This systematic scoping review aimed to uncover how GIS has been used in the GCC states to understand "place" and "health". A comprehensive search of the literature was performed in PubMed, Scopus, Science Citation Index Expanded, ScienceDirect, Embase, IEEE Xplore, and ACM Digital Library during June 2020. All journal articles involving the use of GIS for human health applications in the GCC states published in English in peerreviewed scientific journals were considered. After removing duplicates and applying eligibility criteria, qualitative content analysis was performed for 24 of 630 studies. GIS uses in the GCC states were categorized as health access and planning (n=9), health risk analysis (n=8), disease surveillance (n=6) and community health profiling (n=1). The majority of the uncovered evidence in this study focused on the Kingdom of Saudi Arabia. The results of this study indicate a deficiency of published evidence regarding the use of GIS in support of public health in other GCC states. This stands to compromise planning and strategic decision making in health risk analysis, disease surveillance, community health profiling, health services provision and health interventions.

Ongoing and planned activities to improve the management of patients with Type 1 diabetes across Africa; implications for the future

BACKGROUND

Currently about 19 million people in Africa are known to be living with diabetes, mainly Type 2 diabetes (T2DM) (95%), estimated to grow to 47 million people by 2045. However, there are concerns with early diagnosis of patients with Type 1 diabetes (T1DM) as often patients present late with complications. There are also challenges with access and affordability of insulin, monitoring equipment and test strips with typically high patient co-payments, which can be catastrophic for families. These challenges negatively impact on the quality of care of patients with T1DM increasing morbidity and mortality. There are also issues of patient education and psychosocial support adversely affecting patients' quality of life. These challenges need to be debated and potential future activities discussed to improve the future care of patients with T1DM across Africa.

METHODOLOGY

Documentation of the current situation across Africa for patients with T1DM including the epidemiology, economics, and available treatments within public healthcare systems as well as ongoing activities to improve their future care. Subsequently, provide guidance to all key stakeholder groups going forward utilizing input from senior-level government, academic and other professionals from across Africa.

RESULTS

Whilst prevalence rates for T1DM are considerably lower than T2DM, there are concerns with late diagnosis as well as the routine provision of insulin and monitoring equipment across Africa. High patient co-payments exacerbate the situation. However, there are ongoing developments to address the multiple challenges including the instigation of universal health care and partnerships with non-governmental organizations, patient organizations, and pharmaceutical companies. Their impact though remains to be seen. In the meantime, a range of activities has been documented for all key stakeholder groups to improve future care.

CONCLUSION

There are concerns with the management of patients with T1DM across Africa. A number of activities has been suggested to address this and will be monitored.

The future of cystic fibrosis care: a global perspective

The past six decades have seen remarkable improvements in health outcomes for people with cystic fibrosis, which was once a fatal disease of infants and young children. However, although life expectancy for people with cystic fibrosis has increased substantially, the disease continues to limit survival and quality of life, and results in a large burden of care for people with cystic fibrosis and their families. Furthermore, epidemiological studies in the past two decades have shown that cystic fibrosis occurs and is more frequent than was previously thought in populations of non-European descent, and the disease is now recognised in many regions of the world. The Lancet Respiratory Medicine Commission on the future of cystic fibrosis care was established at a time of great change in the clinical care of people with the disease, with a growing population of adult patients, widespread genetic testing supporting the diagnosis of cystic fibrosis, and the development of therapies targeting defects in the cystic fibrosis transmembrane conductance regulator (CFTR), which are likely to affect the natural trajectory of the disease. The aim of the Commission was to bring to the attention of patients, health-care professionals, researchers, funders, service providers, and policy makers the various challenges associated with the changing landscape of cystic fibrosis care and the opportunities available for progress, providing a blueprint for the future of cystic fibrosis care. The discovery of the CFTR gene in the late 1980s triggered a surge of basic research that enhanced understanding of the pathophysiology and the genotype-phenotype relationships of this clinically variable disease. Until recently, available treatments could only control symptoms and restrict the complications of cystic fibrosis, but advances in CFTR modulator therapies to address the basic defect of cystic fibrosis have been remarkable and the field is evolving rapidly. However, CFTR modulators approved for use to date are highly expensive, which has prompted questions about the affordability of new treatments and served to emphasise the considerable gap in health outcomes for patients with cystic fibrosis between high-income countries, and low-income and middle-income countries (LMICs). Advances in clinical care have been multifaceted and include earlier diagnosis through the implementation of newborn screening programmes, formalised airway clearance therapy, and reduced malnutrition through the use of effective pancreatic enzyme replacement and a high-energy, high-protein diet. Centre-based care has become the norm in high-income countries, allowing patients to benefit from the skills of expert members of multidisciplinary teams. Pharmacological interventions to address respiratory manifestations now include drugs that target airway mucus and airway surface liquid hydration, and antimicrobial therapies such as antibiotic eradication treatment in early-stage infections and protocols for maintenance therapy of chronic infections. Despite the recent breakthrough with CFTR modulators for cystic fibrosis, the development of novel mucolytic, anti-inflammatory, and anti-infective therapies is likely to remain important, especially for patients with more advanced stages of lung disease. As the median age of patients with cystic fibrosis increases, with a rapid increase in the population of adults living with the disease, complications of cystic fibrosis are becoming increasingly common. Steps need to be taken to ensure that enough highly qualified professionals are present in cystic fibrosis centres to meet the needs of ageing patients, and new technologies need to be adopted to support communication between patients and health-care providers. In considering the future of cystic fibrosis care, the Commission focused on five key areas, which are discussed in this report: the changing epidemiology of cystic fibrosis (section 1); future challenges of clinical care and its delivery (section 2); the building of cystic fibrosis care globally (section 3); novel therapeutics (section 4); and patient engagement (section 5). In panel 1, we summarise key messages of the Commission. The challenges faced by all stakeholders in building and developing cystic fibrosis care globally are substantial, but many opportunities exist for improved care and health outcomes for patients in countries with established cystic fibrosis care programmes, and in LMICs where integrated multidisciplinary care is not available and resources are lacking at present. A concerted effort is needed to ensure that all patients with cystic fibrosis have access to high-quality health care in the future.

Urban Green Space Is Spatially Associated with Cardiovascular Disease Occurrence in Women of Mashhad: a Spatial Analysis of Influential Factors on their Presence in Urban Green Spaces

Chronic diseases have spread around the world. Cardiovascular diseases (CVD), the most important of the chronic diseases and the leading cause of death in women of Mashhad, are impacted by environmental factors. Urban green spaces (UGSs) are important environmental factors playing a critical role in the prevention and control of CVD. Spatial analysis is useful in understanding the application of UGSs in CVD prevention. To identify the spatial distribution of CVD in Mashhad, Moran's index was used and 7539 home addresses of female patients with CVD were imported into ArcMap. Moran's coefficient was estimated to be 0.34, revealing a clustered distribution of CVD. The spatial autocorrelation between CVD and UGSs was analyzed using Moran's I. Moran's I index value was calculated to be - 0.15, and four types of clusters were identified in eight sub-districts of Mashhad municipality. To find the factors influencing the presence in UGSs among women affected by CVD, 607 female patients living in the selected sub-districts were asked to take part in a telephone survey. Data were analyzed using ordinary least squares (OLS) and geographically weighted regression (GWR) at block level (343 statistical blocks in total). Accordingly, the spatial diversity and effects of three variables of income, level of education, and access to UGSs among female patients with CVD were measured. According to OLS results and the standard residual, two clusters were removed. Finally, vulnerable blocks were identified that could be helpful in the development of prevention policies and place-based interventions.

Measuring Spatial Patterns of Health Care Facilities and Their Relationships with Hypertension Inpatients in a Network-Constrained Urban System

There is evidence of a strong correlation between inequality in health care access and disparities in chronic health conditions. Equal access to health care is an important indicator for overall population health, and the urban road network has a significant influence on the spatial distribution of urban service facilities. In this study, the network kernel density estimation was applied to detect the hot spots of health care service along the road network of Shenzhen, and we further explored the influences of population and road density on the aggregate intensity distributions at the community level, using spatial stratified heterogeneity analyses. Then, we measured the spatial clustering patterns of health care facilities in each of the ten districts of Shenzhen using the network K-function, and the interrelationships between health care facilities and hypertension patients. The results can be used to examine the reasonability of the existing health care system, which would be valuable for developing more effective prevention, control, and treatment of chronic health conditions. Further research should consider the influence of nonspatial factors on health care service access.

Monitoring viral load for the last mile: what will it cost?

INTRODUCTION

Routine viral load testing is the WHO-recommended method for monitoring HIV-infected patients on ART, and many countries are rapidly scaling up testing capacity at centralized laboratories. Providing testing access to the most remote populations and facilities (the "last mile") is especially challenging. Using a geospatial optimization model, we estimated the incremental costs of accessing the most remote 20% of patients in Zambia by expanding the transportation network required to bring blood samples from ART clinics to centralized laboratories and return results to clinics.

METHODS

The model first optimized a sample transportation network (STN) that can transport 80% of anticipated sample volumes to centralized viral load testing laboratories on a daily or weekly basis, in line with Zambia's 2020 targets. Data incorporated into the model included the location and infrastructure of all health facilities providing ART, location of laboratories, measured distances and drive times between the two, expected future viral load demand by health facility, and local cost estimates. We then continued to expand the modelled STN in 5% increments until 100% of all samples could be collected.

RESULTS AND DISCUSSION

The cost per viral load test when reaching 80% patient volumes using centralized viral load testing was a median of $18.99. With an expanded STN, the incremental cost per test rose to $20.29 for 80% to 85% and $20.52 for 85% to 90%. Above 90% coverage, the incremental cost per test increased substantially to $31.57 for 90% to 95% and $51.95 for 95% to 100%. The high numbers of kilometres driven per sample transported and large number of vehicles needed increase costs dramatically for reaching the clinics that serve the last 5% of patients.

CONCLUSIONS

Providing sample transport services to the most remote clinics in low- and middle-income countries is likely to be cost-prohibitive. Other strategies are needed to reduce the cost and increase the feasibility of making viral load monitoring available to the last 10% of patients. The cost of alternative methods, such as optimal point-of-care viral load equipment placement and usage, dried blood/plasma spot specimen utilization, or use of drones in geographically remote facilities, should be evaluated.

Estimating morbidity due to stroke in Nigeria: a systematic review and meta-analysis

BACKGROUND

The response to stroke in Nigeria is impaired by inadequate epidemiologic information. We sought to collate available evidence and estimate the incidence of stroke and prevalence of stroke survivors in Nigeria.

METHODS

Using random effects meta-analysis, we pooled nationwide and regional incidence and prevalence of stroke from the estimates reported in each study.

RESULTS

Eleven studies met our selection criteria. The pooled crude incidence of stroke in Nigeria was 26.0 (12.8-39.0) /100,000 person-years, with this higher among men at 34.1 (9.7-58.4) /100,000, compared to women at 21.2 (7.4-35.0) /100,000. The pooled crude prevalence of stroke survivors in Nigeria was 6.7 (5.8-7.7) /1000 population, with this also higher among men at 6.4 (5.1-7.6) /1000, compared to women at 4.4 (3.4-5.5) /1000. In the period 2000-2009, the incidence of stroke in Nigeria was 24.3 (95% CI: 11.9-36.8) per 100,000, with this increasing to 27.4 (95% CI: 2.2-52.7) per 100,000 from 2010 upwards. The prevalence of stroke survivors increased minimally from 6.0 (95% CI: 4.6-7.5) per 1000 to 7.5 (95% CI: 5.8-9.1) per 1000 over the same period. The prevalence of stroke survivors was highest in the South-south region at 13.4 (9.1-17.8) /100,000 and among rural dwellers at 10.8 (7.5-14.1) /100,000.

CONCLUSION

Although study period does not appear to contribute substantially to variations in stroke morbidity in Nigeria, an increasing number of new cases compared to survivors may be due in part to limited door-door surveys, or possibly reflects an increasing mortality from stroke in the country.