The state of the global nephrology workforce: a joint ASN–ERA-EDTA–ISN investigation
Authors: Stephen M. Sozio, Kurtis A. Pivert, Fergus J. Caskey, Adeera Levin
Journal: Kidney International (2021)

Chronic kidney disease (CKD) is a global health crisis, affecting 11% to 13% of the world's population.1GBD Chronic Kidney Disease CollaborationGlobal, regional, and national burden of chronic kidney disease, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017.Lancet. 2020; 395: 709-733Abstract Full Text Full Text PDF PubMed Scopus (1247) Google Scholar,2Bello A.K. Levin A. Tonelli M. et al.Assessment of global kidney health care status.JAMA. 2017; 317: 1864-1881Crossref PubMed Scopus (198) Google Scholar Although gaps in the workforce and available training pathways have been explored,3Osman M.A. Alrukhaimi M. Ashuntantang G.E. et al.Global nephrology workforce: gaps and opportunities toward a sustainable kidney care system.Kidney Int. 2018; 8: 52-63Abstract Full Text Full Text PDF Scopus (82) Google Scholar,4Riaz P. Caskey F. McIsaac M. et al.Workforce capacity for the care of patients with kidney failure across world countries and regions.BMJ Global Health. 2021; 6e004014Crossref PubMed Scopus (8) Google Scholar it remains unclear if nephrologist availability, measured as ratios of nephrologists to both the general population and to individuals burdened by CKD, is sufficient for the estimated 850 million individuals with CKD. The scope of kidney health services that nephrologists provide, qualified by local health care environments and practice patterns, may also vary geographically. These variations in how nephrologists are defined, trained, and certified contribute to regional challenges for the kidney specialist pipeline. Lower-income economies lack the resources and health care infrastructure to provide comprehensive nephrology training, whereas declining nephrology interest among medical trainees could constrain the workforce in higher-income countries.5Couser W.G. Remuzzi G. Mendis S. Tonelli M. The contribution of chronic kidney disease to the global burden of major noncommunicable diseases.Kidney Int. 2011; 80: 1258-1270Abstract Full Text Full Text PDF PubMed Scopus (861) Google Scholar,6Sharif M.U. Elsayed M.E. Stack A.G. The global nephrology workforce: emerging threats and potential solutions!.Clin Kidney J. 2016; 9: 11-22Crossref PubMed Scopus (82) Google Scholar To inform efforts to strengthen kidney care capacity, the American Society of Nephrology, European Renal Association–European Dialysis and Transplant Association, and International Society of Nephrology sought to assess the state of the global nephrology workforce. We conducted a cross-sectional survey quantifying the nephrology workforce's adequacy across regional and economic strata, measuring the following: nephrologist-to-population ratios; how nephrologists were trained and certified; and the range of kidney health services provided by nephrologists, other physicians, and allied health professionals. In addition, we considered if survey measures could be surrogate indicators for nephrologist supply and/or demand. We assessed nephrology workforce adequacy using a survey measuring certified nephrologist totals per country; length of nephrology training and certification mechanisms; and primary kidney health providers for multiple therapeutic areas (Supplementary Survey Instrument). The instrument was evaluated for reliability with a global audience, translated into French and Spanish, and distributed to a survey frame comprising 260 stakeholders from nephrology and medical organizations representing 170 countries. In addition, we hypothesized if survey measures could be useful indicators for nephrologist supply and/or kidney care demand. Supply measures included the following: practicing nephrologists per country; nephrologist per-million-population (pmp) ratio; full-time equivalent (FTE) nephrologists, estimated as the proportion of time nephrologists spent solely providing kidney care; and whether countries offered early retirement incentives. Surrogate demand indicators comprised the following: dialysis facilities requiring on-site nephrologists; dialysis rounding frequencies; and ratio of nephrologist per 100,000 population with CKD.1GBD Chronic Kidney Disease CollaborationGlobal, regional, and national burden of chronic kidney disease, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017.Lancet. 2020; 395: 709-733Abstract Full Text Full Text PDF PubMed Scopus (1247) Google Scholar To facilitate comparisons between regions with diverse economies and health care systems, we aggregated results by World Bank regions and income levels.7World BankWorld Bank Country and Lending Groups. Washington, DC: The World Bank Group; 2017.https://datahelpdesk.worldbank.org/knowledgebase/articles/906519-world-bank-country-and-lending-groupsDate accessed: February 22, 2021Google Scholar World Bank income levels were based on nations' 2017 gross national income per capita ($US): low-income (≤$1005), lower-middle-income ($1006–$3955), upper-middle-income ($3956–$12,235), and high-income (>$12,235). Percentages were calculated on a per-question basis, and summary statistics were reported as medians (25th percentile [Q1], 75th percentile [Q3]), or medians (ranges), as appropriate (see Supplementary Complete Methods). A total of 106 countries participated (64% response). Fewer countries from sub-Saharan Africa (29% of countries), Latin American and Caribbean (36%), and East Asia and Pacific (39%) were represented than from Europe and Central Asia (74%), North America (67%), South Asia (63%), and the Middle East and North Africa (62%). Only 35% of low-income nations (11 countries) responded versus ≥50% of those in high-income (40 counties), upper-middle-income (31 countries), and lower-middle-income (24 countries) economic strata. Estimates (63 countries) or accurate data (36 countries) on total certified nephrologists per country ranged from 0 (Papua New Guinea) to 10,083 (United States; median, 150 [26, 350] nephrologists per country). Globally, a median 9.1 (2.3, 24.9) nephrologists pmp were in practice, yet medians varied from 0.3 (0.2, 0.7) nephrologists pmp in low-income countries to 26.5 (15.9, 32.1) nephrologists pmp in high-income nations (range, 0–58 nephrologists pmp). There was substantial regional variation in nephrologist pmp ratios: sub-Saharan Africa reported a median 0.5 (0.25, 1.2) nephrologists pmp versus 25.3 (22.5, 28.1) nephrologists pmp in North America (Table 11GBD Chronic Kidney Disease CollaborationGlobal, regional, and national burden of chronic kidney disease, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017.Lancet. 2020; 395: 709-733Abstract Full Text Full Text PDF PubMed Scopus (1247) Google Scholar).Table 1Nephrologist totals and ratios of nephrologists per million population and per 100,000 population with CKD by World Bank regions and income levelsVariableNephrologistsNephrologists per million populationNephrologists per 100,000 population with CKDaCKD prevalence obtained from GBD Chronic Kidney Disease Collaboration.1World Bank regionsNorth America5392 (3046, 7737)25.3 (22.5, 28.1)23.1 (21.6, 24.5)Latin America and Caribbean214 (60, 366)8.9 (7.7, 12.6)12.0 (7.3, 14.5)Europe and Central AsiabValues reported for 43 participating nations in the Europe and Central Asia World Bank region and aggregated by individual continent—Europe (37 countries) and Central Asia (6 countries).150 (42, 350)20.1 (10.8, 30.2)20.3 (10.4, 28.0) Europe155 (48, 358)25.7 (12.9, 31.1)25.6 (10.9, 28.0) Central Asia135 (20, 200)8.7 (6.6, 10.8)7.7 (4.6, 11.3)Middle East and North Africa150 (43, 225)5.9 (2.8, 14.0)6.1 (3.1, 14.5)Sub-Saharan Africa18 (8, 26)0.5 (0.25, 1.2)0.8 (0.5, 1.7)South Asia150 (30, 200)1.0 (1.0, 1.3)1.3 (1.1, 1.4)East Asia and Pacific312 (77, 738)5.9 (0.8, 15.3)6.0 (1.0, 15.1)World Bank income levelsHigh-income270 (85, 650)26.5 (15.9, 32.1)25.7 (14.3, 28.3)Upper-middle-income180 (90, 400)8.8 (6.2, 13.0)7.7 (5.2, 12.7)Lower-middle-income72 (24, 188)1.5 (0.8, 4.5)1.8 (1.0, 4.2)Low-income11 (7, 20)0.3 (0.2, 0.7)0.6 (0.4, 0.9)CKD, chronic kidney disease.Data are given as median (25th percentile [Q1], 75th percentile [Q3]).a CKD prevalence obtained from GBD Chronic Kidney Disease Collaboration.1GBD Chronic Kidney Disease CollaborationGlobal, regional, and national burden of chronic kidney disease, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017.Lancet. 2020; 395: 709-733Abstract Full Text Full Text PDF PubMed Scopus (1247) Google Scholarb Values reported for 43 participating nations in the Europe and Central Asia World Bank region and aggregated by individual continent—Europe (37 countries) and Central Asia (6 countries). Open table in a new tab CKD, chronic kidney disease. Data are given as median (25th percentile [Q1], 75th percentile [Q3]). We calculated ratios of nephrologists to the estimated CKD population per country using Global Burden of Disease data.1GBD Chronic Kidney Disease CollaborationGlobal, regional, and national burden of chronic kidney disease, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017.Lancet. 2020; 395: 709-733Abstract Full Text Full Text PDF PubMed Scopus (1247) Google Scholar Median nephrologists per 100,000 population with CKD ranged from 0.8 (0.5, 1.7) in sub-Saharan Africa to 23.1 (21.6, 24.5) in North America. Income-level variation was acute, with only an estimated 0.6 (0.4, 0.9) nephrologists per 100,000 with CKD in low-income countries. FTE nephrologist estimates (58 countries) were 50.8% lower than nephrologist totals: median of 73.8 FTE nephrologists versus a median of 150 certified nephrologists per country. Across economic strata, deficits in nephrology service capacity (between median accredited nephrologist and median FTE nephrologist estimates) were similar, with low- and lower-middle-income countries reporting 45% and 64% fewer FTE nephrologists, respectively. Regional differences were pronounced in Latin America and Caribbean, Middle East and North Africa, and South Asia (all reporting ≥60% fewer FTE nephrologists). The nephrology workforce was predominantly male (range, 20%–30% women), with the highest proportion of female nephrologists (44%) in upper-middle-income economies. Only 6 countries offered early retirement incentives. Training duration was calculated by summing years of medical school with the length of either: (i) medical residency plus nephrology residency/fellowship for single nephrology accreditation; or (ii) joint medical-nephrology residency/fellowship for joint nephrology accreditation. Nephrologists undergo a median 12 (10, 13) years of training (median, 6 [6, 6] years of medical school plus median 6 [4, 7] years of specialist training). Duration varied widely regardless of pathway—median range of 9.0–13.0 years for single accreditation and median range of 9.0–12.5 years for joint accreditation. Governments were principal funders of nephrology training (36%–58%), except South Asia, where 50% of countries indicated trainees pay for their subspecialty education. Physicians in lower-middle-income and upper-middle-income countries were also likely to self-fund their nephrology training (33% and 35%, respectively). Most countries (66%) certify nephrologists using a combination of written examinations (56% of countries), clinical examinations (51%), and/or formal appraisal of clinical experience (50%). Overall, certification was not time limited (71%), with 24% of countries requiring recertification every 5 to 10 years. Globally, nephrologists address all major areas of kidney care. Acute kidney injury, CKD, dialysis, end-stage kidney disease, glomerulonephritis, hypertension, and kidney transplantation were managed by nephrologists in 77% to 93% of countries. In many areas, nephrologists performed dedicated roles (CKD [78 countries], dialysis [77 countries], and glomerulonephritis [75 countries]) or formally subspecialized (adult-pediatric nephrology [36 countries], intensive care unit [27 countries], interventional [26 countries], and transplant [26 countries]). Nephrologists were primary physicians across most kidney care areas (Figure 1), including CKD stages 4–5, end-stage kidney disease, and glomerulonephritis; living donor evaluation and preoperative/postoperative transplant care; and chronic dialysis modalities (all in ≥89% of countries). Other physicians also provided continuous kidney replacement therapy (other specialists, 33%; and nephrologists, 67%), managed CKD stages 1–3 (primary care providers, 36%; and nephrologists, 55%), and hypertension (other specialists, 49%; and nephrologists, 47%). Primary physicians varied by economy, with nephrologists in low-income nations responsible for nearly all kidney care and those in high-income countries sharing primary roles in acute kidney injury, CKD stages 1–3, and continuous kidney replacement therapy. Registered nurses (RNs) and physician assistants (PAs) make substantial contributions to kidney care, providing chronic hemodialysis (HD) (RNs, 48%; and PAs, 32%), chronic peritoneal dialysis (RNs, 48%; and PAs, 29%), and acute HD (RNs, 34%; and PAs, 33%). Nephrologists prescribed and performed acute dialysis (87 and 69 countries, respectively) and kidney biopsy (84 and 67 countries, respectively), but less frequently performed other procedures, including continuous kidney replacement therapy (39 countries), catheter insertion (tunneled, 40 countries; peritoneal dialysis, 31 countries), and arteriovenous fistulas (9 countries) (Figure 2). Practice varied regionally (e.g., tunneled catheter insertion: South Asia [60%] vs. Europe and Central Asia [26%]). Many nephrologists work within public/government (36%) or public/private (50%) health systems, practicing in hospitals (clinics for CKD [90%], dialysis [90%], or kidney transplantation [77%]), outpatient clinics (CKD [80%] or transplantation [54%]), dialysis centers (75%), and intensive care units (48%). On-site nephrologists are required at most hospital and in-center HD facilities (64%). Nephrologists commonly round at every HD session in hospitals (46%), every in-center HD session (31%), and—when available—monthly for home modalities (peritoneal dialysis, 58%; and home HD, 18%). Some variation in rounding was attributable to lack of home modalities (in low-income/lower-middle-income countries), although upper-middle-income and high-income nations demonstrated similar in-center HD rounding patterns (Figure 3). See Supplementary Tables S1–S4 and Supplementary Figures S1–S4 for detailed respondent, nephrologists/population, training, and practice pattern results. Regardless of region or local economy, nephrologists are the primary kidney care providers. Given this finding, and the growing burden of CKD fueled by increasing diabetes and hypertension prevalence, nephrology workforce disparities seen in this study are concerning. To mitigate these disparities, policies are needed to expand capacity by standardizing training, broadening dialysis/kidney care access, and optimizing the existing nephrology workforce through adoption of nephrology teams. Most countries provided some form of nephrology training (98 countries) and certification (96 countries), but differences in training length, dialysis access, and practice patterns indicate variability in workforce adequacy. Lack of faculty and varying health infrastructure can impede effective nephrology education in developing economies, where a tailored approach driven by local needs and resources—focused on stemming upstream risk factors (diabetes and hypertension) and utilizing a team-based approach—could help develop and ensure efficient use of the global nephrology workforce.8Vachharajani T.J. Bello A.K. Evans R. et al.Nephrology education and continuing education in resource-limited settings.Semin Nephrol. 2017; 37: 224-233Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar,9Okel J. Okpechi I.G. Qarni B. et al.Nephrology training curriculum and implications for optimal kidney care in the developing world.Clin Nephrol. 2016; 86: 110-113Crossref PubMed Scopus (7) Google Scholar With little literature on recommended workforce levels—and recognizing the heterogeneity of global health care—minimum nephrologist baselines should be established to guide workforce development, especially in low-income/lower-middle-income countries, comprising ∼46% of global population.10Liyanage T. Ninomiya T. Jha V. et al.Worldwide access to treatment for end-stage kidney disease: a systematic review.Lancet. 2015; 385: 1975-1982Abstract Full Text Full Text PDF PubMed Scopus (988) Google Scholar,11Thurlow J.S. Joshi M. Yan G. et al.Global epidemiology of end-stage kidney disease and disparities in kidney replacement therapy.Am J Nephrol. 2021; 52: 98-107Crossref PubMed Scopus (43) Google Scholar Uneven availability of kidney replacement therapy3Osman M.A. Alrukhaimi M. Ashuntantang G.E. et al.Global nephrology workforce: gaps and opportunities toward a sustainable kidney care system.Kidney Int. 2018; 8: 52-63Abstract Full Text Full Text PDF Scopus (82) Google Scholar,4Riaz P. Caskey F. McIsaac M. et al.Workforce capacity for the care of patients with kidney failure across world countries and regions.BMJ Global Health. 2021; 6e004014Crossref PubMed Scopus (8) Google Scholar—with individuals in lower economic settings comprising just 7% of individuals on dialysis—contributes to the high premature mortality rate of those not able to receive kidney replacement therapy, estimated at 3 times that of those receiving kidney replacement therapy.10Liyanage T. Ninomiya T. Jha V. et al.Worldwide access to treatment for end-stage kidney disease: a systematic review.Lancet. 2015; 385: 1975-1982Abstract Full Text Full Text PDF PubMed Scopus (988) Google Scholar,11Thurlow J.S. Joshi M. Yan G. et al.Global epidemiology of end-stage kidney disease and disparities in kidney replacement therapy.Am J Nephrol. 2021; 52: 98-107Crossref PubMed Scopus (43) Google Scholar Beyond primary care providers and other specialists, nurse practitioners, physician assistants, and registered nurses played a vital role in kidney care. These are only some of the team members critical to delivering optimal kidney care, many of whom face similar workforce deficits.9Okel J. Okpechi I.G. Qarni B. et al.Nephrology training curriculum and implications for optimal kidney care in the developing world.Clin Nephrol. 2016; 86: 110-113Crossref PubMed Scopus (7) Google Scholar Access to training and inadequate funding are disincentives to global nephrology workforce capacity expansion. Regular assessments of the global nephrology workforce capacity are critical to ensuring the success of any policies. FTE nephrologists is a more conservative—perhaps more realistic—surrogate indicator for workforce supply than point estimates. Lower FTE estimates we observed could indicate nephrologists are providing generalist/other medical care, constraining kidney health service availability. The ratio of nephrologists to prevalent CKD population could provide more meaningful workforce assessments, especially as CKD is asymptomatic until its later stages. Although the ratio of nephrologists per individuals with end-stage kidney disease also indicated a nephrologist deficit, this framing is less generalizable given the uneven global access to kidney replacement therapies.6Sharif M.U. Elsayed M.E. Stack A.G. The global nephrology workforce: emerging threats and potential solutions!.Clin Kidney J. 2016; 9: 11-22Crossref PubMed Scopus (82) Google Scholar,10Liyanage T. Ninomiya T. Jha V. et al.Worldwide access to treatment for end-stage kidney disease: a systematic review.Lancet. 2015; 385: 1975-1982Abstract Full Text Full Text PDF PubMed Scopus (988) Google Scholar,11Thurlow J.S. Joshi M. Yan G. et al.Global epidemiology of end-stage kidney disease and disparities in kidney replacement therapy.Am J Nephrol. 2021; 52: 98-107Crossref PubMed Scopus (43) Google Scholar Although our study featured a granular survey instrument and introduced a novel metric for assessing nephrology workforce adequacy, it has several limitations. Kidney ultrasonography—a skill introduced in the core curriculum of nephrologists in many countries—was not assessed in this study.12O'Neill W.C. Renal relevant radiology: use of ultrasound in kidney disease and nephrology procedures.Clin J Am Soc Nephrol. 2014; 9: 373-381Crossref PubMed Scopus (47) Google Scholar In addition, the uneven representation among low-income nations, potential for reduced reliability among a nonnative English-speaking audience and/or physicians working in different health system structures, and completion before the advent of the coronavirus disease 2019 (COVID-19) pandemic could bias our results and make them less generalizable. In conclusion, nephrologist pmp ratios indicate kidney care is inadequate in many regions, especially because nephrologists are the primary kidney care providers. Quantifying regional variations can inform efforts to strengthen the nephrology workforce and harmonize training, ensuring appropriate care for people with kidney diseases. KAP is an employee of the American Society of Nephrology. All the other authors declared no competing interests. Interim results of this work were presented in poster form at American Society of Nephrology (ASN) Kidney Week 2018 at San Diego, CA. The authors are grateful to the respondents who contributed their insights to the Global Nephrology Workforce Survey. The authors also thank ASN Executive Vice President Tod Ibrahim, MA; European Renal Association–European Dialysis and Transplant Association Executive Director Monica Fontana, MA; and International Society of Nephrology Executive Director Charu Malik, PhD, for their support of this work. Download .pdf (3.31 MB) Help with pdf files Supplementary File (PDF)