The prevalence of chronic kidney disease in South Africa - limitations of studies comparing prevalence with sub-Saharan Africa, Africa, and globally

Cost-effectiveness and budget impact analysis of peritoneal dialysis and haemodialysis in South Africa

BACKGROUND

More than 800 million people are affected by chronic kidney disease (CKD) worldwide. In South Africa, the prevalence of CKD increased by 67% between 1999 and 2006. Haemodialysis (HD), peritoneal dialysis (PD), and kidney transplant are the three main modalities used for managing end stage kidney disease. The cost of these therapies poses a significant burden to the health care system in South Africa. The aim of this study is to determine the cost-effectiveness and budget impact of peritoneal dialysis versus haemodialysis from the societal perspective in South Africa.

METHODS

A Markov model was constructed to estimate the cost-effectiveness of peritoneal dialysis versus haemodialysis. The model was developed in excel and populated with clinical evidence and cost data synthesized from the literature. The costs and outcomes were estimated over a 5-year time-horizon. The outcomes were presented as quality-adjusted life years. Cost effectiveness was estimated using the incremental cost-effectiveness ratio and the incremental net monetary benefit (INMB). Probabilistic sensitivity analysis was also conducted to assess the robustness of the results. A budget impact model was constructed to estimate the impact of PD and HD over a 5 year period.

RESULTS

The total discounted costs per patient over 5 years were R788 384 for PD versus R1 227 708 for HD. The incremental cost for providing PD was estimated at -R438 875. The net QALYs for delivering PD compared to HD were estimated at -0.09. Cost effectiveness ratio for PD versus PD was R5 096 154/QALY. At a threshold of R38 500, PD provision has a 79% probability of being cost-effective relative to HD. The INMB was estimated at R328 574 for PD and R322 194 for HD indicating the cost-effectiveness of PD. The budget impact analysis showed that it would cost government approximately R25 billion over 5 years to treat all individuals eligible for KRT under the current scenario of 88% HD and 12% PD.

CONCLUSIONS

In South Africa, PD is shown to be cost-effective at a willingness to pay threshold of less than R38 500. A PD-preferred policy that considers clinical appropriateness and patients' values should be considered.

UMOD Genotype and Determinants of Urinary Uromodulin in African Populations

Introduction

Single-nucleotide polymorphisms (SNPs) in the UMOD -PDILT genetic locus are associated with chronic kidney disease (CKD) in European populations, through their effect on urinary uromodulin (uUMOD) levels. The genetic and nongenetic factors associated with uUMOD in African populations remain unknown.

Methods

Clinical parameters, 3 selected UMOD-PDILT SNPs and uUMOD levels were obtained in 1202 young Black and White adults from the African-PREDICT study and 1943 middle aged Black adults from the PURE-NWP-SA study, 2 cross-sectional, observational studies.

Results

Absolute uUMOD and uUMOD/creatinine levels were lower in Black participants compared to White participants. The prime CKD-risk allele at rs12917707 was more prevalent in Black individuals, with strikingly more risk allele homozygotes compared to White individuals. Haplotype analysis of the UMOD-PDILT locus predicted more recombination events and linkage disequilibrium (LD) fragmentation in Black individuals. Multivariate testing and sensitivity analysis showed that higher uUMOD/creatinine associated specifically with risk alleles at rs12917707 and rs12446492 in White participants and with higher serum renin and lower urine albumin-to-creatinine ratio in Black participants, with a significant interaction of ethnicity on the relationship between all 3 SNPs and uUMOD/creatinine. The multiple regression model explained a greater percentage of the variance of uUMOD/creatinine in White adults compared to Black adults (23% vs. 8%).

Conclusion

We evidenced ethnic differences in clinical and genetic determinants of uUMOD levels, in particular an interaction of ethnicity on the relationship between CKD-risk SNPs and uUMOD. These differences should be considered when analyzing the role of uromodulin in kidney function, interpreting genome-wide association studies (GWAS), and precision medicine recommendations.

Sociodemographic and Economic Correlates of Dialysis Vintage in a Resource Challenged Setting: A Four-Year Prospective Study in Southwest Nigeria

Background

Dialysis vintage is largely dependent on the effectiveness of the delivered dose coupled with the extent of patient compliance with the prescribed treatment regimen. This study assessed the determinants and correlates of dialysis vintage. Methodology: This was a 4-year prospective, observational study. The data was collected from the dialysis and medical records, both had the contacts of patients and relatives.

Results

A total of 314 participants (males 67.20%) with a mean age of 47.91±8.81 years underwent 2265 maintenance haemodialysis sessions. The females were older and had more hospital admissions; (P=0.07). Approximately 32.17% of the participants traveled at least fifty kilometers to access dialysis treatment. In a month, only 23.57% of the participants received the minimum prescribed twelve sessions, and 24.84% received the required erythropoietin dose. The mean dialysis vintage for all population was 9.13 ± 3.15 months, it was shorter for participants with hospitalization, (p<0.001), dialysis termination (p<0.001), intradialytic hypotension (p<0.001), and hypertension (p<0.001), Approximately, 14.2% of the participants had health insurance coverage, more so with the men After dialysis initiation, 6.69% of the participants were alive to the fourth year. The predictors of dialysis vintage were income (OR-4.62, 95% CI-2.88-6.24), health insurance (OR-8.11, 95% CI-4.82-13.35), dialysis duration (OR-6.38, 95% CI-2.40-9.55) and spKt/V (OR-4.24, 95% CI-0.48-5.91).

Conclusion

Dialysis vintage was short (9.13 ± 3.15 months), more so in females, poor funding, peridialysis complications, and without health insurance. More concerted efforts from governments, multinational donor agencies, and philanthropists are needed in health insurance coverage, particularly for kidney care to increase the dialysis vintage.

A conceptual framework to improve the quality of life in patients with CKD on dialysis in KwaZulu Natal Province, South Africa

Chronic kidney disease (CKD) is one non-communicable disease mainly caused by comorbid of diabetes and hypertension, thus compromising quality of life for the patients. Few rigorous Quality of Life frameworks on chronic kidney disease (CKD) have been reported in low-middle income countries including South Africa. Therefore, the study aimed at developing a Conceptual Framework to improve the Quality of Life in Patients with CKD on Dialysis in KwaZulu Natal Province, South Africa. A Mixed method sequential explanatory design which entails collection of quantitative data, followed by qualitative. A purposive sampling of 316 CKD patients for quantitative was initially selected. For qualitative, 17 healthcare professionals were theoretically sampled until data saturation. A structured questionnaire (WHO HRQOL-BREF) was utilized to collect numerical data for quantitative phase, while focus group discussions provided qualitative insights. The quantitative results indicated low quality of life (QoL) in several dimensions: economic (98 %), psychological (95 %), physical (70 %), and social (55 %). Grounded theory analysis of the qualitative data identified key predictors of QoL as the patients' geographic location, accessibility to haemodialysis centres, their ability to adapt and accept the condition, self-management practices, support from family members and caregivers including the presence of well-trained nursing staff. A comprehensive conceptual framework was developed through identifying contextual factors, interventions and outcomes that is expected to improve the QOL. The study recommends the immediate intervention of the policy makers and health care providers in drafting and implementing policies to improve the QOL in patients with CKD.

Cost-benefit analysis of haemodialysis in patients with end-stage kidney disease in Abuja, Nigeria

BACKGROUND

Significant gaps in scholarship on the cost-benefit analysis of haemodialysis exist in low-middle-income countries, including Nigeria. The study, therefore, assessed the cost-benefit of haemodialysis compared with comprehensive conservative care (CCC) to determine if haemodialysis is socially worthwhile and justifies public funding in Nigeria.

METHODS

The study setting is Abuja, Nigeria. The study used a mixed-method design involving primary data collection and analysis of secondary data from previous studies. We adopted an ingredient-based costing approach. The mean costs and benefits of haemodialysis were derived from previous studies. The mean costs and benefits of CCC were obtained from a primary cross-sectional survey. We estimated the benefit-cost ratios (BCR) and net benefits to determine the social value of the two interventions.

RESULTS

The net benefit of haemodialysis (2,251.30) was positive, while that of CCC was negative (-1,197.19). The benefit-cost ratio of haemodialysis was 1.09, while that of CCC was 0.66. The probabilistic and one-way sensitivity analyses results demonstrate that haemodialysis was more cost-beneficial than CCC, and the BCRs of haemodialysis remained above one in most scenarios, unlike CCC's BCR.

CONCLUSION

The benefit of haemodialysis outweighs its cost, making it cost-beneficial to society and justifying public funding. However, the National Health Insurance Authority requires additional studies, such as budget impact analysis, to establish the affordability of full coverage of haemodialysis.

The Future of Kidney Care in Low- and Middle-Income Countries: Challenges, Triumphs, and Opportunities

CKD affects about 850 million people worldwide and is projected to be the fifth leading cause of death by 2040. Individuals from low- and middle-income countries (LMICs) bear the bulk of CKD. They face challenges including lack of awareness among the general population, as well as health care providers, unique risk factors such as genetic predispositions, infectious diseases, and environmental toxins, limited availability and affordability of diagnostic tests and medications, and limited access to KRTs. The inadequate health system infrastructure, human resources, and financing mechanisms to support comprehensive and integrated kidney care worsen the situation. Overcoming these challenges needs concerted efforts toward early detection, intervention, and multidisciplinary follow-up, policy, collaboration, advocacy, and financing. To achieve this, there is need for individual governments to include kidney health among the key health priorities and build capacity toward resilient health care systems. Integrating kidney care using the roadmaps of well-established management systems for other chronic diseases, such as HIV, has the potential to expedite the widespread adoption of kidney health. The aim of this article is to provide an overview of the current state and future prospects of kidney care in LMICs, highlighting the main challenges, ongoing efforts, and opportunities for improvement. We present case studies of exemplary efforts from three continents of the world with the highest densities of LMICs and propose potential strategies for a sustainable solution.

Prevalence and progression of chronic kidney disease among adults undergoing creatinine testing in South African public healthcare facilities: a study leveraging data from South Africa's National Health Laboratory Service (NHLS)

Background

Chronic kidney disease (CKD) has emerged as a substantial global health challenge, with a marked rise in associated mortality. However, it often goes undetected until advanced stages, particularly in low-income and middle-income countries such as South Africa. We investigated the prevalence and progression of CKD in South Africa, utilising a subset of data from the National Health Laboratory Services Multi-morbidity Cohort.

Methods

This study was a retrospective analysis of adults aged 18-85 years who underwent initial creatinine laboratory testing at government hospitals and clinics from January 2012 to January 2016. CKD was assessed using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, excluding the race factor, with a cut-off of CKD-EPI<60 mL/min/1.73 m2. Lab-diagnosed CKD was defined as two estimated glomerular filtration rate measurements <60 mL/min/1.73 m2 at least 90 days apart. Cox regression and survival curves were used to estimate HRs and rates of progression.

Results

Among 6 106 521 adults tested between 2012 and 2016, 1.5% (95% CI 1.4% to 1.5%) were diagnosed with CKD, with the majority in stage 3. Over follow-up (median: 2 years, IQR: 0.8-3.6 years), 28.2% (95% CI 27.7% to 28.6%) of patients diagnosed as stage 3a progressed to a more severe disease state. Among patients who were in stage 3b at diagnosis, 29.6% (95% CI 29.0% to 30.1%) progressed and 33.3% (95% CI 32.5% to 34.1%) of stage 4 patients progressed. We estimated a 48% higher adjusted hazard of CKD progression for individuals with diabetes (adjusted HR 1.48, 95% CI 1.41 to 1.57) compared with those without. Advancing age also increased the risk, particularly for those aged >50 years.

Conclusions

This study underscores the urgency for early detection and management of CKD in South Africa, particularly for high-risk individuals. Strengthening primary healthcare systems and raising CKD awareness are vital for improved patient outcomes and to alleviate the burden on healthcare resources. Early intervention can delay CKD progression, thus reducing the need for costly treatments like dialysis and transplantation.

Comparing a range of potassium-enriched low sodium salt substitutes to common salt: Results of taste and visual tests in South African adults

BACKGROUND AND AIMS

Potassium-enriched low sodium salt substitutes (LSSS), which replace a proportion of sodium chloride (NaCl) with potassium chloride (KCl), have been shown to reduce blood pressure and offer a potential solution to address the high burden of hypertension in South Africa. However, it is unknown which proportions of KCl in LSSS are acceptable. We compared the taste and visual acceptability of various LSSS in South African adults.

METHODS AND RESULTS

Fifty-six adults underwent double-blind taste and visual tests of four LSSS (35%KCl/65%NaCl; 50%KCl/50%NaCl; 66%KCl/34%NaCl; 100%KCl) in comparison to 100%NaCl (common salt). Participants scored each product by taste ranking, taste perception and likeliness to use. Participants then visually inspected the five products and attempted to identify which was which. Almost half (45 %) of participants ranked the taste of 50%KCl/50 %NaCl as fantastic or really good. Furthermore, 62 % of participants liked and would be happy to use the 50 %KCl/50 %NaCl or felt this tasted like common salt. Only 12 % rated the 100%KCl highly for taste, and over half reported being unlikely to use this. Most participants (57.3 % and 36.4 %) were able to visually identify 100%NaCl and 100%KCl, while identification of other blends was generally poor. Responses were similar for 35%KCl/65%NaCl and 66%KCl/34%NaCl throughout.

CONCLUSION

Our findings suggest that the taste of the 50%KCl salt substitute would be well tolerated by South African adults, most of which could not visually differentiate between this salt substitute and common salt.

A systematic review assessing the potential use of cystatin c as a biomarker for kidney disease in people living with HIV on antiretroviral therapy

The introduction of antiretroviral therapy (ART) has significantly prolonged the lifespan of people living with human immunodeficiency virus (PLWH). However, the sustained use of this drug regimen has also been associated with a cluster of metabolic anomalies, including renal toxicity, which can lead to the development of kidney diseases. In this study, we reviewed studies examining kidney disease in PLWH sourced from electronic databases such as PubMed/MEDLINE, Scopus, and Google Scholar, as well as gray literature. The narrative synthesis of data from these clinical studies demonstrated that the serum levels of cystatin C remained unchanged or were not affected in PLWH on ART, while the creatinine-based glomerular filtration rate (GFR) fluctuated. In fact, some of the included studies showed that the creatinine-based GFR was increased in PLWH taking tenofovir disoproxil fumarate-containing ART, perhaps indicating that the use of both cystatin C- and creatinine-based GFRs is vital to monitor the development of kidney disease in PLWH. Clinical data summarized within this study indicate the potential detrimental effects of tenofovir-based ART regimens in causing renal tubular injury, while highlighting the possible beneficial effects of dolutegravir-based ART on improving the kidney function in PLWH. However, the summarized literature remains limited, while further clinical studies are required to provide insights into the potential use of cystatin C as a biomarker for kidney disease in PLWH.

Proteomic insights into the pathophysiology of hypertension-associated albuminuria: Pilot study in a South African cohort

BACKGROUND

Hypertension is an important public health priority with a high prevalence in Africa. It is also an independent risk factor for kidney outcomes. We aimed to identify potential proteins and pathways involved in hypertension-associated albuminuria by assessing urinary proteomic profiles in black South African participants with combined hypertension and albuminuria compared to those who have neither condition.

METHODS

The study included 24 South African cases with both hypertension and albuminuria and 49 control participants who had neither condition. Protein was extracted from urine samples and analysed using ultra-high-performance liquid chromatography coupled with mass spectrometry. Data were generated using data-independent acquisition (DIA) and processed using Spectronaut™ 15. Statistical and functional data annotation were performed on Perseus and Cytoscape to identify and annotate differentially abundant proteins. Machine learning was applied to the dataset using the OmicLearn platform.

RESULTS

Overall, a mean of 1,225 and 915 proteins were quantified in the control and case groups, respectively. Three hundred and thirty-two differentially abundant proteins were constructed into a network. Pathways associated with these differentially abundant proteins included the immune system (q-value [false discovery rate] = 1.4 × 10- 45), innate immune system (q = 1.1 × 10- 32), extracellular matrix (ECM) organisation (q = 0.03) and activation of matrix metalloproteinases (q = 0.04). Proteins with high disease scores (76-100% confidence) for both hypertension and chronic kidney disease included angiotensinogen (AGT), albumin (ALB), apolipoprotein L1 (APOL1), and uromodulin (UMOD). A machine learning approach was able to identify a set of 20 proteins, differentiating between cases and controls.

CONCLUSIONS

The urinary proteomic data combined with the machine learning approach was able to classify disease status and identify proteins and pathways associated with hypertension-associated albuminuria.