Saudi Journal of Kidney Diseases and Transplantation

ORIGINAL ARTICLE
Year
: 2016  |  Volume : 27  |  Issue : 7  |  Page : 51--61

Gulf Cooperation Council-dialysis outcomes and practice patterns study: An overview of anemia management trends at the regional and country specific levels in the Gulf Cooperation Council countries


Samra Abouchacra1, Ali Obaidli2, Saeed M. G. Al-Ghamdi3, Jamal Al Wakeel4, Issa Al Salmi5, Sumaya Al Ghareeb6, Mohammad Al Azmi7, Mohammed Elsayed8, Brian A Bieber9, Ronald L Pisoni9, GCC-DOPPS 5 Study Group10,  
1 Department of Medicine, Tawam Hospital, Al Ain, United Arab Emirates
2 Department of Medicine, Sheikh Khalifa Medical City, Abu Dhabi, United Arab Emirates
3 Department of Medicine, King Abdulaziz University Hospital, Jeddah, Saudi Arabia
4 Department of Medicine, King Saud University, Riyadh, Saudi Arabia
5 Department of Medicine, The Royal Hospital, Muscat, Oman
6 Department of Medicine, Salmaniya Medical Complex, Manama, Bahrain
7 Department of Medicine, Dar Al Shifa Hospital, Hawally, Kuwait
8 Department of Medicine, Hamad General Hospital, Doha, Qatar
9 Arbor Research Collaborative for Health, Ann Arbor, MI, USA
10 List of Study Group in Acknowledgment

Correspondence Address:
Samra Abouchacra
Department of Medicine, Tawam Hospital, Al Ain
United Arab Emirates

Abstract

The Gulf Cooperation Council-Dialysis Outcomes and Practice Patterns Study (GCC-DOPPS) marks the joining of the six Gulf region countries including Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates to the main DOPPS study in 2012. The current review is a descriptive reporting on results related to the management of anemia from these countries. Our data demonstrate consistent anemia management patterns across the GCC countries allowing the achievement of international treatment levels. Overall, the majority of hemodialysis patients were prescribed appropriate erythropoiesis-stimulating agents (ESAs) and supplemental iron, enabling the attainment of mean hemoglobin (Hb) level of 10.9 g/dL. Comparisons of the individual country profiles reveal individual differences in the choice and mode of ESA and iron administration. However, all countries displayed good compliance with guideline recommendations. The same challenges as elsewhere are faced in the GCC, with respect to optimizing Hb levels and judiciously using ESA and iron supplements. Some opportunities exist for focused efforts to fine tune inter-facility variability in anemia management based on continued data tracking. The latter is vital in enabling adopting new trends to further improve not only anemia management but also the wholesome care of dialysis patients.



How to cite this article:
Abouchacra S, Obaidli A, Al-Ghamdi SM, Al Wakeel J, Al Salmi I, Al Ghareeb S, Al Azmi M, Elsayed M, Bieber BA, Pisoni RL, GD. Gulf Cooperation Council-dialysis outcomes and practice patterns study: An overview of anemia management trends at the regional and country specific levels in the Gulf Cooperation Council countries.Saudi J Kidney Dis Transpl 2016;27:51-61


How to cite this URL:
Abouchacra S, Obaidli A, Al-Ghamdi SM, Al Wakeel J, Al Salmi I, Al Ghareeb S, Al Azmi M, Elsayed M, Bieber BA, Pisoni RL, GD. Gulf Cooperation Council-dialysis outcomes and practice patterns study: An overview of anemia management trends at the regional and country specific levels in the Gulf Cooperation Council countries. Saudi J Kidney Dis Transpl [serial online] 2016 [cited 2020 Apr 3 ];27:51-61
Available from: http://www.sjkdt.org/text.asp?2016/27/7/51/194895


Full Text

 Introduction



The Dialysis Outcomes and Practice Patterns Study (DOPPS) is a prospective, observational cohort study examining data from nationally representative samples of hemodialysis (HD) facilities to describe associations between HD facility practices and key outcomes for HD patients. [1] The first phase of DOPPS began in 1996 in the United States, followed by the participation of France, Germany, Italy, Spain and the UK in 1998, and Japan in 1999. Other countries were subsequently added with the latest addition being the inclusion of the Gulf Cooperation Council (GCC) countries in 2012. The GCC-DOPPS is involved in data collection from the six Gulf region countries, namely, the United Arab Emirates (UAE), Bahrain, Saudi Arabia, Kuwait, Oman, and Qatar. The current review is a descriptive reporting on results from these GCC countries specifically related to anemia management.

Anemia is not only common in HD patients, but also associated with significant morbidity and mortality. [2],[3],[4],[5],[6] Moreover, its management is challenging despite the development of treatment guidelines, including Kidney Disease Improving Global Outcomes, European Renal Association's Best Practice Guidelines [7] , and Dialysis Outcomes Quality Initiative of the US National Kidney Foundation (NKF-DOQI). [7],[8],[9],[10] Difficulties are still faced in achieving stable hemoglobin (Hb) levels and maintaining optimal dosing of both erythropoiesis-stimulating agents (ESA) and iron formulations to reach these levels and still avoid their associated detrimental effects. This study explores the composite patterns of anemia management and outcomes from the GCC countries as a group as well as comparisons of the individual profiles of each of the participating countries.

 Methods



Data were from phase 5 of the DOPPS, an international prospective cohort study in 21 countries. The DOPPS is based on nationally representative samples of randomly selected dialysis facilities and patients. Facilities participating in the Phase 5 GCC-DOPPS were randomly selected from a list of all dialysis units within each of the six participating countries. Only facilities having at least 24 HD patients were eligible for the study participation. These facilities typically serve >90% of all facilitybased HD patients in each country. The selection was stratified in a way that the facility samples provide proportional representation of the types of HD units and geographic regions within each country. The main analyses were performed on 927 adult chronic HD patients who were enrolled at the start of the GCCDOPPS Phase 5 study from 40 GCC HD units participating in DOPPS 5. All six GCC countries were represented in this DOPPS phase 5 study. All study HD patients were aged >18 years at entry to the study. Further details of the GCC-DOPPS study design are provided in the "The DOPPS Phase 5 Study in the GCC Countries: Design and Study Methods" paper by Pisoni et al in this special Supplement issue of the Saudi Journal of Kidney Disease and Transplantation.

Baseline descriptive statistics (e.g., mean, median, and percentage) were calculated for the study sample, stratified to country, and gender. Descriptive statistics for each country were derived from the initial cross-section of selected patients and weighted by facility sampling fraction (sampled patients/total number of patients at the facility) to provide nationally representative statistics. Use of ESAs or iron preparations was calculated based on prescription at any time during the month at the time of the study enrollment.

All statistical analyses were performed using SAS software, version 9.4 (SAS Institute Inc. 2013. SAS® 9.4 Guide to Software Updates. Cary, NC: SAS Institute Inc.)

 Results



Observational data were reported on 928 HD patients from all six GCC countries [Table 1] with the majority of patients being from Saudi Arabia and the UAE, 390 and 220, respectively. Overall, there were 77% Arab nationals, 12% non-Arab nationals, and 11% belonging to other nationalities (non nationals of all other nationalities, Asians, European, north Americans, Africans, Australians etc.). However, the percentage of nationals within the DOPPS study sample varied by country with a uniformly national cohort in Bahrain (100%) and Oman (97%) to 49% in Qatar and 57% in the UAE. Patient characteristics for the group as a whole and by gender are shown in [Table 1] and [Table 2], respectively. There was a greater predominance of males in each country [Table 1], with a similar mean age, but longer dialysis vintage and higher body mass index (BMI) for females compared to males [Table 2]. The mean Hb concentration, however, was identical for both groups at 10.9 ± 3.3 g/dL with no gender difference [Figure 1].{Figure 1}{Table 1}{Table 2}

With respect to anemia management, 88% of both men and women were prescribed an ESA, 53% were prescribed intravenous (i.v.) iron and about 20% were on oral iron formulation [Table 2]. The type of ESA had an almost even split between i.v. short-acting Epoetin and long-acting Darbepoetin, with a small percentage of patients treated with pegylated epoetin beta and subcutaneous ESA [Figure 2] and [Table 2]. Compared to men, women had a higher median (inter-quartile range) Epoetin dose equivalent [8667 (5333, 1333) units/week vs. 8000 (5333, 13333) units/week for males] as well as greater median i.v. iron dose [333 (217, 435) mg/month vs. 290 (169, 435) mg/ month for males, [Table 2]. This was also linked to higher median serum ferritin levels in women versus men (419 ng/mL vs. 362 ng/ mL); the mean transferrin saturation (TSAT) percentage was similar in males and females. With respect to i.v. iron formulations, ferrous saccharide was prescribed in over 60% of both males and females with approximately 10% of patients treated with iron dextran [Table 2].{Figure 2}

Inter-country variability

Demographic characteristics were comparable in Bahrain, Oman, and Saudi Arabia with similar average age of approximately 51 years, whereas patients from Qatar, on average, were a whole decade older [Table 1]. Although there was a slight predominance of men in all GCC countries, this was more pronounced in Qatar and the UAE. Kuwaiti patients had the highest BMI at 28.9, followed by Bahrainis, and the lowest BMI among the study patients was in Oman at 23.9 kg/m 2 where a greater representation of non-Omanis was seen. The Hb levels showed some variability between GCC countries, with a mean Hb level of 11.1 g/dL observed in Kuwait and Qatar, with mean Hb concentrations closely approaching this level in Saudi Arabia (10.9 g/dL), and with mean Hb levels of 10.7 g/dL in Oman, and the UAE, and 10.4 g/dL in Bahrain. Importantly, however, none of the participating countries had an achieved mean Hb level <10 g/dL as shown in [Figure 1].

There was a widespread high rate of use of ESA in all GCC countries, ranging from 100% in Bahrain to 80% in Saudi Arabia. Nevertheless, there appeared to be no consistent relationship between achieved Hb levels and the prevalence of ESA use or use of iron or their respective doses. However, it seemed that the two countries with the highest Hb levels, namely, Kuwait and Qatar, were in fact among the highest in percentage of patients prescribed i.v. iron, yet the monthly dose was surprisingly in the lower range. Moreover, in Qatar, the mean Hb level was also associated with a relatively high percentage of ESA use as well as fairly high i.v. epoetin dose equivalent, being second only to Bahrain. Bahrain also had high use of i.v. iron and the highest ESA and iron dosing, yet interestingly achieved the lowest mean Hb level [Figure 3]. The prevalence of sickle cell disease in the general population in Bahrain is 2.1% with sickle cell trait seen in 11%. [11] Investigators from Bahrain have indicated a relatively high prevalence of sickle cell anemia among HD patients in Bahrain. This has not been documented in DOPPS phase 5 but is included in the new DOPPS phase 6 data collection beginning in 2016. Recent work by Derebail et al has shown that higher ESA doses were given to US African-American HD patients with sickle cell trait to achieve the same Hb level as those without sickle cell trait. [12]{Figure 3}

Kuwait and Saudi Arabia, on the other hand, had the lowest mean i.v. epoetin dose equivalent at 8000 units/week, but their Hb levels were among the top three countries, despite intermediate mean i.v. iron doses. Moreover, the percentage of i.v. iron use was distinctly different among them, constituting 68% in Kuwait and 38% in Saudi; the latter being the lowest among all GCC countries and additionally linked with the highest use of oral iron.

The type of ESA also appeared to have little relationship with the mean Hb level achieved. Moreover, tremendous variability was observed between the GCC countries regarding the use of longer versus shorter acting ESA formulations [Figure 4]. Epoetin was predominantly used in Oman, Bahrain, and Qatar (100%, 76%, 64%, respectively) whereas Darbepoetin was used predominantly in Kuwait at 98%. The two remaining GCC countries, namely, the UAE and Saudi Arabia, had an almost even split in the use of Epoetin and Darbepoetin. Subcutaneous ESA was used primarily in Saudi Arabia in 15% of patients while 0-4% of patients in all other GCC countries received subcutaneous administration of ESAs.{Figure 4}

Some inconsistencies were observed in the choice and route of iron administration among the GCC countries. i.v. iron sucrose was the predominant formulation used in all GCC countries except Bahrain. It was the only formulation used in Oman and Qatar whereas in Bahrain, 35% of patients received iron dextran, and the others were given other non-sucrose, non-gluconate iron formulations. In addition, wide differences were seen in the mean monthly dose of i.v. iron among countries with Oman and Bahrain having the highest median monthly i.v. iron dose at 435 mg, with Qatar and UAE having the lowest at 217 mg. Nevertheless, the higher dose of supplemental iron was not associated with lower prescribed ESA doses or higher achieved Hb levels, whereas lower i.v. iron doses on the other hand, seemed to be linked with the prescription of higher ESA doses when viewed at the country level [Figure 5]. {Figure 5}

Although the median serum ferritin levels were >200 ng/mL in all patients across GCC countries, the highest median ferritin levels were seen in the UAE at 449 ng/mL and Kuwait at 438 ng/mL; the latter had the highest achieved mean Hb level with the lowest ESA dose. The lowest ferritin levels were seen in Oman with an intermediate i.v. epoetin dose and achieved Hb levels [Figure 6]. Interestingly, the mean TSAT percentage was highest in Qatar and Saudi Arabia (30.7% and 30.0%, respectively) and was associated with relatively high Hb levels. Mean TSAT levels were lowest in Bahrain (16.2%) and accompanied with the lowest achieved mean Hb level [Figure 7].{Figure 6}{Figure 7}

 Discussion



The mean Hb concentration in GCC DOPPS closely approached the recommended international target levels in a consistent fashion, with none of the participating countries showing a mean Hb level below 10 g/dL. This is reflective of not only individual physician efforts in embracing and disseminating international guidelines within their units but is also indicative of the tremendous administration, governmental and policymaker involvement in ensuring the provision of care of high quality and according to internationally recommended benchmarks. This is shown by the availability of the essential infrastructural requirements as well as the ongoing focus on participation in quality initiatives and performance evaluations to assess and track compliance.

It is worth emphasizing that overall, there was comprehensive care provision to dialysis patients as well as the widespread application of standard practices which has enabled the achievement of the recommended Hb levels for most patients. This is seen in the consistent and high overall ESA use across all GCC countries, seen in 88% of HD patients. Moreover, since effective iron management is crucial to achieve maximum ESA effectiveness and optimal Hb levels, it is reassuring that a high prevalence of supplemental iron use of 73%, was seen in all GCC countries. Although there was some observed variation in the i.v. iron compound used as well as the route of iron administration, this is likely related to the availability of different agents in the respective hospital formularies.

When examining country-specific data, there was some minor variability in achieved Hb levels among participating countries. Not surprisingly, countries with the highest Hb levels were in fact among the most frequent users of iron and ESA. Nevertheless, inter-country comparisons did not show consistent relationship with the prevalence of ESA use or ESA dosage, nor use or average monthly dose of iron. This is likely to be due to the relatively minor differences in achieved Hb levels and the uniform guideline-driven practice patterns making the effect of these variations insignificant. In addition, the type of ESA agent had little relationship with achieved Hb levels that were observed despite tremendous differences between countries in their individual agent of choice. Of note, however, there was little overall use of subcutaneous ESA.

Across all, the randomly selected HD units participating in GCC-DOPPS, the mean weekly epoetin equivalent dose was 8335 IU which was higher in women and might be explained by their higher BMI. Interestingly, lower ESA dose was not necessarily associated with lower mean Hb levels, which was clearly demonstrated in both Kuwait and Saudi Arabia, and inciden-tally they also had lower average iron doses. Moreover, the percentage of use of i.v. iron was distinctly different among GCC countries ranging from 38 to 73%, with the trend suggesting that higher i.v. iron use was not the only therapy contributing to the achievement of observed Hb levels. Importantly, i.v. iron sucrose was the predominantly used formulation in all GCC countries. Use of oral iron did not adversely affect achieved Hb levels. This was seen with data from Saudi Arabia where almost 50% of administered iron was the oral form and still achieving a Hb level of 10.9 g/dL.

The mean ferritin levels were all within recommended target levels and it appeared that higher ferritin levels were associated with lower monthly iron doses and linked to achieving higher Hb levels. A similar relationship was observed with TSAT but was not necessarily directly proportional to administered iron dose. However, when TSAT was below 20%, it appeared to be linked to the attainment of lower Hb levels and higher requirement of ESA and iron dose, which could also be due to greater inflammation which was not described in these analyses.

 Conclusion



Effective anemia management is of key importance in the treatment of dialysis patients. GCC-DOPPS data demonstrate consistent anemia management across GCC countries closely approaching international guidelines of level ≥11 g/dL. The same challenges are faced in GCC as elsewhere, with respect to optimizing Hb levels and judiciously using ESA and iron supplementation. This is especially important in this region, in which expanded health coverage is present allowing for more liberal prescribing. Overall, a good proportion of HD patients within GCC countries is on supplemental ESA and iron, both of which are key elements to achieving target levels. It is clear that there are still good opportunities for continued efforts to improve anemia management and fine tune inter-facility variability based on regular data tracking. We are counting on sustained future participation in DOPPS study to adopt new trends to further enhance the delivery of quality care in the GCC countries.

 Acknowledgments



We wish to thank the devoted efforts of GCC-DOPPS 5 Study Group members for their numerous contributions to this study including Country Investigators (Dr. Sameer Al-Arrayed, Dr. Sumaya Al Ghareeb, Dr. Bassam Al Helal, Dr. Naser Alkandari, Dr. Ali Alsahow, Dr. Anas AlYousef, Dr. Mohammad AlAzmi, Dr. Yaqob Ahmed Almaimani, Dr. Issa Alsalmi, Dr. Nabil Salmeen Mohsin, Dr. Fadwa Al Ali, Dr. Mohamed El-Sayed Abdel Fatah, Dr. Ashraf Fawzy, Dr. Abdulla Hamad, Dr. Saeed M. G. Al-Ghamdi, Dr. Mohammed Al Ghonaim, Dr. Jamal Al Wakeel, Dr. Fayez Hejaili, Dr. Ayman Karkar, Dr. Faissal Shaheen, Dr. Samra Abouchacra, Dr. Ali Abdulkarim Al Obaidli, Dr. Mohamed Hassan, Dr. Mona Nasir Al Rukhaimi, and Dr. Abdul Kareem Saleh, Dr. Sylvia Ramirez, Dr. Bruce Robinson, Dr. Ronald Pisoni), Clinical Research Associates and Project Coordinators/Managers (Dr. Amgad El-Baz El-Agroudy, Dr. Balaji Dandi, Ms. Cherry Flores, Mrs. Ph. Fatma Al Raisi, Ms. Ibtisam Al-Hasni, Dr. Ashraf Fawzy, Dr. Haroun Zakaria Ahmed and Mr. Dan Santiago from the Saudi Center for Organ Transplantation, Mr. Muhammad Awwad, Ms. Roberta Al Housani-Blakely, Christina Pustulka, Anne Vandermade, Melissa Fava, Anna Hogan, Michelle Maxim, Justin Albert), Biostatisticians (Brian Bieber), and Study Site Medical Directors, and Study Coordinators: Dr. Hamid Ali Alyousif, Ms. Sohair Abdulroof Albably, Dr. Ahmed Eid Alkady, Dr. Samir Al Muielo, MD, Dr. Fakreldein Elamien Ali, Dr. Ayman El Monger, Dr. Sameh Mohammed Al-sammad, Dr. Baraa Rajab, Dr. Atif Hanan, Tarek Abdelfattah Ahmed Ali, Dr. Ayman Karkar, Dr. Mohammed Abdelrahman, Dr. Mohammed Hussein, Dr. Wael Abdlah, Dr. Faisal Mushtaq, Dr. Salah Eldin El Sheik Beshir, Dr. Medhat Abdelmonem Shalaby, Dr. Mustafa Khaleel Al Obeid, Dr. Mohamad El Hadary, Dr. Alaa Al Shamy; Dr. Aboud Mamari, Dr. Mohammed Raily, Dr. Mustafa Ahmed; Ramzi AbouAyache, Dr. Hormoz Dastoor, Dr. Mohamed Hassan, Dr. Bassam Bernieh, Dr. Hareth Muthanna Mohammed Saaed, Dr. Mustafa Kamel, Prof. Abdel Basset Hassan, MD, PhD, FASN, Dr. Hassan Khammas, Dr. Balaji Dandi, Dr. Sumaya Al-Ghareeb, Dr. Fadwa Al Ali, Dr. Anas Alyousef, Dr. Nasser AlKandari, Dr. Ali Alsahow, Dr. Bassam AlHelal, Dr. Ahmed Mandour, Dr. Yaqob Ahmed Almaimani, Dr. Amer Ahmed Alaamri, Dr. Ibrahim Sayed Ibrahim, Dr. El Badri Abdelgadir, Dr. Mohammed Al-Sayed Seleem, Dr. Ali Hassan Hakami; Dr. Samir Beshay, Dr. Nayer Morsy, Mr Menwer Al-ofi, Ms. Sohair Abdulroof Albably, Dr. Huda Mohammed Saeed Ahmed, Ola Al-Marhoon; Dr. Samir Al Muielo, Ms. Joynalyn Barrios, Ms. Fatima Cruza; Ligaya Battad, Mr. Abdullah A.K. al Harbi, Dr. Sameh Mohammed Al-sammad, Ms. Manal Ahmed Hamdan, Jennifer Samson, Mr. Ahmed mousa Khawaji, Ms. Eman Al-Hejji, Ms. Rosalinda Lamis, Ms. Lagrimas Codotco, Dr. Wael Abdlah, Mrs Priyanka Prasad, RN, Mr. Bander Faisal Justinia, Mr. Faisal Al Enazy, Sarah Brazil, Dr. Naemah Abdullah, Dr. Alaa Al Shamy, Dr. Aboud Mamari, Mely Gari Piling, Dr. Fakhriya Al Alwai, Rusmina Binti Sudin, Dr. Chandra Mauli Jha, MD; Katheryn Jamilano, Basima Khaddah, Hilal Al Rasbi, Muhy Eddin Hashem Hasan, Sr. Ekram Awadh Salem, Walid Gouiaa, Mini Issac, Jiby Mammen, Mary Ellen Monday, Mrs. Afrah Al Jamri, Mr. Yasser Khalil Abbas, Mrs. Rania Abd El-Aziz, Rania Abd El-Aziz, Cherry Flores, Mini Kumari Ramakrishnan, Shanty Mannaraprayil, Maria Charisse Bernardo, Bassam AlHelal, Evangeline Valdez, Rosily Joseph, Mrs. Ghaniya Al Shukaili, Adel Mohamed Bayoumy, Hamid Alshahri, Amira Balkhair, Amina Said Al Shezawi, Sultan Saif Ali Alroshdi, Dr. Shaninaz Faisal Bashir, Dr. Ahmed Mousa Dawood, Keirin Porras, Dr. Anthonimuthu Victor, Mr. Sultan Al-Toqi.

 Source of Support



The DOPPS program is supported by Amgen, Kyowa Hakko Kirin, AbbVie, Sanofi Renal, Baxter Healthcare, and Vifor Fresenius Medical Care Renal Pharma. Additional support for specific projects and countries is provided by Keryx Biopharmaceuticals, Merck Sharp & Dohme Corp., Proteon Therapeutics, Relypsa, and F. Hoffmann-LaRoche; in Canada by Amgen, BHC Medical, Janssen, Takeda, and the Kidney Foundation of Canada (for logistics support); in Germany by Hexal, DGfN, Shire, and the WiNe Institute; and for PDOPPS in Japan by the Japanese Society for Peritoneal Dialysis (JSPD). All support is provided without restrictions on publications.

Conflict of interest: None declared.

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