Nephrol Dial Transplant (2014) 29: 1770–1777 doi: 10.1093/ndt/gft472 Advance Access publication 8 December 2013
Original Article Two-times weekly hemodialysis in China: frequency, associated patient and treatment characteristics and Quality of Life in the China Dialysis Outcomes and Practice Patterns study Brian Bieber1*, Jiaqi Qian2,*, Shuchi Anand3, Yucheng Yan2, Nan Chen4, Mia Wang1, Mei Wang5, Li Zuo6,7, Fan Fan Hou8, Ronald L. Pisoni1, Bruce M. Robinson1 and Sylvia P.B. Ramirez1 1
Arbor Research Collaborative for Health, Ann Arbor, MI, USA, 2Renal Division, Renji Hospital, Shanghai Jiaotong University School of
Medicine, Shanghai, China, 3Division of Nephrology, Stanford University School of Medicine, Palo Alto, CA, USA, 4Department of Nephrology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China, 5People’s Hospital, Peking University, Beijing, China, 6
Peking University First Hospital, Beijing, China, 7Institute of Nephrology, Peking University, Beijing, China and 8Division of Nephrology,
Nanfang Hospital, Southern Medical University, Guangzhou, China
Correspondence and offprint requests to: B. Bieber; E-mail: [email protected] * Co-first author.
associated with dialyzing two times weekly (versus three times weekly). Patients dialyzing two times per week had longer treatment times and lower standardized Kt/V, but similar quality of life scores. Conclusions. Two-times weekly dialysis is common in China, particularly among patients, who started dialysis more recently, have a lower comorbidity burden and have financial constraints. Quality of life scores do not differ between the twotimes and three-times weekly groups. The effect on clinical outcomes merits further study.
A B S T R AC T Background. Renal replacement therapy is rapidly expanding in China, and two-times weekly dialysis is common, but detailed data on practice patterns are currently limited. Using cross-sectional data from the China Dialysis Outcomes and Practice Patterns Study (DOPPS), we describe the hemodialysis practice in China compared with other DOPPS countries, examining demographic, social and clinical characteristics of patients on two-times weekly dialysis. Methods. The DOPPS protocol was implemented in 2011 among a cross-section of 1379 patients in 45 facilities in Beijing, Guangzhou and Shanghai. Data from China were compared with a cross section of 11 054 patients from the core DOPPS countries (collected 2009–11). Among China DOPPS patients, logistic and linear regression were used to describe the association of dialysis frequency with patient and treatment characteristics and quality of life. Results. A total of 26% of the patients in China were dialyzing two times weekly, compared with < 5% in other DOPPS regions. Standardized Kt/V was lowest in China (2.01) compared with other regions (2.12–2.27). Female sex, shorter dialysis vintage, lower socioeconomic status, less health insurance coverage, and lack of diabetes and hypertension were
© The Author 2013. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.
Keywords: hemodialysis adequacy, hemodialysis frequency, outcomes, practice patterns, quality of life
INTRODUCTION The prevalence of chronic kidney disease (CKD) in China approaches that of the United States [1]. The use of renal replacement therapy (RRT) for patients reaching end-stage renal disease (ESRD) is rising rapidly: in Shanghai, the incidence of RRT more than doubled between 2000 and 2005 [2]. Though there are regional variations, a majority of patients with ESRD are on hemodialysis (HD) [3]. However, data on HD practice and outcomes remain sparse.
1770
M AT E R I A L S A N D M E T H O D S Patients and data collection Begun in 1996, the DOPPS is an international prospective cohort study of HD patients ≥18 years of age in Australia, Belgium, Canada, France, Germany, Italy, Japan, New Zealand, Spain, Sweden, the United Kingdom and the United States (core DOPPS countries). Patients in the DOPPS are selected randomly from a representative sample of HD facilities within each nation [10, 11]. In 2011, cross-sectional data were collected in China using the baseline DOPPS questionnaires and study protocols. Due to feasibility considerations, the China study was limited to representative data from the metropolitan areas in the three largest cities in China (Beijing, Guangzhou and Shanghai). These cities were identified based on feasibility of data collection and availability of registry information should a comparison between DOPPS and registry data be required. In each metropolitan area, 15 HD facilities were randomly selected from a comprehensive roster of HD units (total selected Chinese HD facilities = 45). Study approval and patient consent were obtained as required by national and local ethics committee regulations. A study coordinator at each participating site collected clinical data. At the time of patient enrollment, the study coordinator abstracted demographic data, comorbid conditions, laboratory values, insurance status and medications from patient records. Practice-level data were obtained through a survey administered to the medical director at each facility. Individual patients completed a questionnaire that included the Kidney Disease Quality of Life-Short Form (KDQOL-SF) 12
China DOPPS dialysis adequacy and vascular access
and questions related to socioeconomic status [12, 13]. Singlepool Kt/V was calculated using the Daugirdas formula among patients dialyzing 3 × per week for at least 1 year. To account for patients dialyzing at a frequency other than three times per week, a standardized Kt/V was calculated from the equation reported by Leypoldt et al. [14]. Normalized protein catabolic rate (nPCR) was calculated by the equations reported by Depner and Daugirdas [15]. Data from 10 947 patients sampled in the DOPPS 4 prevalent cross section of HD patients in the core DOPPS countries between 2009 and 2011 were compared with data from 1379 prevalent Chinese patients collected in 2011. Standard descriptive analyses were used to characterize the DOPPS patients and practices in each country as well as within China, by frequency of dialysis. Generalized estimating equation (GEE) models with a logit link were used to describe the adjusted association of patient characteristics with two-times (versus three-times) per week HD, accounting for facility clustering. Mixed models were used to describe the adjusted association between HD frequency and laboratory values and quality of life, accounting for facility clustering. All analyses used SAS software, version 9.2 (SAS Institute, Cary, NC). R E S U LT S Facility and patient characteristics Of the 45 sampled facilities from the three metropolitan areas in China (Beijing, Guangzhou and Shanghai), 23 were academic or military facilities and 22 were non-academic facilities. On average, the Chinese facilities treated a comparable number of HD patients (95) to facilities in Japan (97). In contrast, facilities in North America and Europe-Australia/New Zealand (EUR-A/NZ) treated substantially fewer patients on average (∼72) (Table 1). Compared with study patients in the other DOPPS regions, the Chinese patients were younger, more likely to be female and less likely to have diabetes as the cause of ESRD (Table 1). Time on dialysis in China was comparable with that in North America and Eur-A/NZ, but shorter than in Japan. The average body mass index (BMI) among patients in China was similar to that in Japan but lower than in North America and Eur-A/NZ. Dialysis access and prescription A native arteriovenous (AV) fistula for HD access was used by 88% of China DOPPS patients compared with 91% in Japan, 58% in North America and 70% in Eur-A/NZ (Table 1). The mean number of prescribed HD sessions per week was lower in China (2.8) than in the other DOPPS countries (range 3.0–3.1) (Table 1, Figure 1A). Twenty-six percent of HD patients in China were dialyzing less than three times weekly (88% of this group were undergoing two-times weekly dialysis) compared with 1–6% in other DOPPS countries. The median Chinese facility reported 26% of patients dialyzing less than three times weekly (22% two times weekly) compared with a range of 0–4% for the median facility in other DOPPS countries (Figure 1B).
1771
ORIGINAL ARTICLE
The recently launched Chinese Renal Data System and published data from city registries have reported that a significant proportion of patients are on two-times weekly HD [2, 4– 6]. Given that patients may shoulder a significant share of cost for HD care in China [7], complex factors—such as patients’ comorbidity burden, residual function, preference to start HD gradually and insurance status—may underlie a decision to pursue two-times weekly dialysis. The effect on Chinese patients’ health-related quality of life (HR-QOL) and survival is unknown. Using cross-sectional data from the China Dialysis Outcomes and Practice Patterns (DOPPS) study, we describe the current state of HD in China in comparison with other DOPPS countries. We also tested the hypothesis that the decision to pursue two-times weekly HD would be related to both clinical and economic factors. As such, we expected that patients with lower comorbidity burden, greater residual function, shorter dialysis vintage (i.e., years since initiation of dialysis) and greater share of cost for treatment would be more likely to undergo two-times weekly HD. Despite attempts to select a ‘healthier’ group of patients for less frequent dialysis, we expected that this group would face a greater likelihood of ‘inadequate’ dialysis therapy and require strict diet restrictions. We therefore hypothesized that this group would exhibit poorer control of anemia and markers of mineral-bone disease, and experience worse quality of life [8, 9].
Table 1. Facility and patient characteristics by region
ORIGINAL ARTICLE
Measure Facility characteristics Facility, n Facility size Facility size, range Patient demographics Study population, n Age, years Female, % Time on dialysis, years Urine output >1 cup/day, %a BMI, kg/m2 Comorbidities Cause of ESRD, % Diabetes Glomerular disease Other Comorbidities, % Coronary heart disease Congestive heart failure Cerebrovascular disease Peripheral vascular disease Other cardiovascular disease Diabetes Hypertension Dialysis prescription # Prescribed HD sessions/week Dialysis session length, min Blood flow rate, mL/min Single-pool Kt/V b Single-pool Kt/V
Original Article Two-times weekly hemodialysis in China: frequency, associated patient and treatment characteristics and Quality of Life in the China Dialysis Outcomes and Practice Patterns study Brian Bieber1*, Jiaqi Qian2,*, Shuchi Anand3, Yucheng Yan2, Nan Chen4, Mia Wang1, Mei Wang5, Li Zuo6,7, Fan Fan Hou8, Ronald L. Pisoni1, Bruce M. Robinson1 and Sylvia P.B. Ramirez1 1
Arbor Research Collaborative for Health, Ann Arbor, MI, USA, 2Renal Division, Renji Hospital, Shanghai Jiaotong University School of
Medicine, Shanghai, China, 3Division of Nephrology, Stanford University School of Medicine, Palo Alto, CA, USA, 4Department of Nephrology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China, 5People’s Hospital, Peking University, Beijing, China, 6
Peking University First Hospital, Beijing, China, 7Institute of Nephrology, Peking University, Beijing, China and 8Division of Nephrology,
Nanfang Hospital, Southern Medical University, Guangzhou, China
Correspondence and offprint requests to: B. Bieber; E-mail: [email protected] * Co-first author.
associated with dialyzing two times weekly (versus three times weekly). Patients dialyzing two times per week had longer treatment times and lower standardized Kt/V, but similar quality of life scores. Conclusions. Two-times weekly dialysis is common in China, particularly among patients, who started dialysis more recently, have a lower comorbidity burden and have financial constraints. Quality of life scores do not differ between the twotimes and three-times weekly groups. The effect on clinical outcomes merits further study.
A B S T R AC T Background. Renal replacement therapy is rapidly expanding in China, and two-times weekly dialysis is common, but detailed data on practice patterns are currently limited. Using cross-sectional data from the China Dialysis Outcomes and Practice Patterns Study (DOPPS), we describe the hemodialysis practice in China compared with other DOPPS countries, examining demographic, social and clinical characteristics of patients on two-times weekly dialysis. Methods. The DOPPS protocol was implemented in 2011 among a cross-section of 1379 patients in 45 facilities in Beijing, Guangzhou and Shanghai. Data from China were compared with a cross section of 11 054 patients from the core DOPPS countries (collected 2009–11). Among China DOPPS patients, logistic and linear regression were used to describe the association of dialysis frequency with patient and treatment characteristics and quality of life. Results. A total of 26% of the patients in China were dialyzing two times weekly, compared with < 5% in other DOPPS regions. Standardized Kt/V was lowest in China (2.01) compared with other regions (2.12–2.27). Female sex, shorter dialysis vintage, lower socioeconomic status, less health insurance coverage, and lack of diabetes and hypertension were
© The Author 2013. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.
Keywords: hemodialysis adequacy, hemodialysis frequency, outcomes, practice patterns, quality of life
INTRODUCTION The prevalence of chronic kidney disease (CKD) in China approaches that of the United States [1]. The use of renal replacement therapy (RRT) for patients reaching end-stage renal disease (ESRD) is rising rapidly: in Shanghai, the incidence of RRT more than doubled between 2000 and 2005 [2]. Though there are regional variations, a majority of patients with ESRD are on hemodialysis (HD) [3]. However, data on HD practice and outcomes remain sparse.
1770
M AT E R I A L S A N D M E T H O D S Patients and data collection Begun in 1996, the DOPPS is an international prospective cohort study of HD patients ≥18 years of age in Australia, Belgium, Canada, France, Germany, Italy, Japan, New Zealand, Spain, Sweden, the United Kingdom and the United States (core DOPPS countries). Patients in the DOPPS are selected randomly from a representative sample of HD facilities within each nation [10, 11]. In 2011, cross-sectional data were collected in China using the baseline DOPPS questionnaires and study protocols. Due to feasibility considerations, the China study was limited to representative data from the metropolitan areas in the three largest cities in China (Beijing, Guangzhou and Shanghai). These cities were identified based on feasibility of data collection and availability of registry information should a comparison between DOPPS and registry data be required. In each metropolitan area, 15 HD facilities were randomly selected from a comprehensive roster of HD units (total selected Chinese HD facilities = 45). Study approval and patient consent were obtained as required by national and local ethics committee regulations. A study coordinator at each participating site collected clinical data. At the time of patient enrollment, the study coordinator abstracted demographic data, comorbid conditions, laboratory values, insurance status and medications from patient records. Practice-level data were obtained through a survey administered to the medical director at each facility. Individual patients completed a questionnaire that included the Kidney Disease Quality of Life-Short Form (KDQOL-SF) 12
China DOPPS dialysis adequacy and vascular access
and questions related to socioeconomic status [12, 13]. Singlepool Kt/V was calculated using the Daugirdas formula among patients dialyzing 3 × per week for at least 1 year. To account for patients dialyzing at a frequency other than three times per week, a standardized Kt/V was calculated from the equation reported by Leypoldt et al. [14]. Normalized protein catabolic rate (nPCR) was calculated by the equations reported by Depner and Daugirdas [15]. Data from 10 947 patients sampled in the DOPPS 4 prevalent cross section of HD patients in the core DOPPS countries between 2009 and 2011 were compared with data from 1379 prevalent Chinese patients collected in 2011. Standard descriptive analyses were used to characterize the DOPPS patients and practices in each country as well as within China, by frequency of dialysis. Generalized estimating equation (GEE) models with a logit link were used to describe the adjusted association of patient characteristics with two-times (versus three-times) per week HD, accounting for facility clustering. Mixed models were used to describe the adjusted association between HD frequency and laboratory values and quality of life, accounting for facility clustering. All analyses used SAS software, version 9.2 (SAS Institute, Cary, NC). R E S U LT S Facility and patient characteristics Of the 45 sampled facilities from the three metropolitan areas in China (Beijing, Guangzhou and Shanghai), 23 were academic or military facilities and 22 were non-academic facilities. On average, the Chinese facilities treated a comparable number of HD patients (95) to facilities in Japan (97). In contrast, facilities in North America and Europe-Australia/New Zealand (EUR-A/NZ) treated substantially fewer patients on average (∼72) (Table 1). Compared with study patients in the other DOPPS regions, the Chinese patients were younger, more likely to be female and less likely to have diabetes as the cause of ESRD (Table 1). Time on dialysis in China was comparable with that in North America and Eur-A/NZ, but shorter than in Japan. The average body mass index (BMI) among patients in China was similar to that in Japan but lower than in North America and Eur-A/NZ. Dialysis access and prescription A native arteriovenous (AV) fistula for HD access was used by 88% of China DOPPS patients compared with 91% in Japan, 58% in North America and 70% in Eur-A/NZ (Table 1). The mean number of prescribed HD sessions per week was lower in China (2.8) than in the other DOPPS countries (range 3.0–3.1) (Table 1, Figure 1A). Twenty-six percent of HD patients in China were dialyzing less than three times weekly (88% of this group were undergoing two-times weekly dialysis) compared with 1–6% in other DOPPS countries. The median Chinese facility reported 26% of patients dialyzing less than three times weekly (22% two times weekly) compared with a range of 0–4% for the median facility in other DOPPS countries (Figure 1B).
1771
ORIGINAL ARTICLE
The recently launched Chinese Renal Data System and published data from city registries have reported that a significant proportion of patients are on two-times weekly HD [2, 4– 6]. Given that patients may shoulder a significant share of cost for HD care in China [7], complex factors—such as patients’ comorbidity burden, residual function, preference to start HD gradually and insurance status—may underlie a decision to pursue two-times weekly dialysis. The effect on Chinese patients’ health-related quality of life (HR-QOL) and survival is unknown. Using cross-sectional data from the China Dialysis Outcomes and Practice Patterns (DOPPS) study, we describe the current state of HD in China in comparison with other DOPPS countries. We also tested the hypothesis that the decision to pursue two-times weekly HD would be related to both clinical and economic factors. As such, we expected that patients with lower comorbidity burden, greater residual function, shorter dialysis vintage (i.e., years since initiation of dialysis) and greater share of cost for treatment would be more likely to undergo two-times weekly HD. Despite attempts to select a ‘healthier’ group of patients for less frequent dialysis, we expected that this group would face a greater likelihood of ‘inadequate’ dialysis therapy and require strict diet restrictions. We therefore hypothesized that this group would exhibit poorer control of anemia and markers of mineral-bone disease, and experience worse quality of life [8, 9].
Table 1. Facility and patient characteristics by region
ORIGINAL ARTICLE
Measure Facility characteristics Facility, n Facility size Facility size, range Patient demographics Study population, n Age, years Female, % Time on dialysis, years Urine output >1 cup/day, %a BMI, kg/m2 Comorbidities Cause of ESRD, % Diabetes Glomerular disease Other Comorbidities, % Coronary heart disease Congestive heart failure Cerebrovascular disease Peripheral vascular disease Other cardiovascular disease Diabetes Hypertension Dialysis prescription # Prescribed HD sessions/week Dialysis session length, min Blood flow rate, mL/min Single-pool Kt/V b Single-pool Kt/V
