Mortality rates among maintenance hemodialysis (MHD) patients in China are lower than those among MHD patient in the United States, and the reason may be differences in race or practice pattern, according to a new study.
The study, by Li Zuo, MD, of Peking University First Hospital in Beijing, China, and colleagues, included 11,675 MHD patients from 104 dialysis centers in Beijing and 1,937,819 MHD patients in the U.S. Renal Data System (USRDS). The raw mortality for the Beijing cohort (per 1,000 patient-years) increased from 47.8 in 2007 to 76.8 in 2010, the researchers reported online ahead of print in Nephrology Dialysis Transplantation. In the USRDS cohort, the raw mortality rate rose for white patients rose from 250.7 in 2007 and 236.3 in 2009. For African-Americans, the rate was 167.8 in 2007 and 156.7 in 2009. For Asian-Americans, the rate was 157.6 and 247.9 for those years, respectively.
In adjusted analyses, the Beijing cohort had a survival benefit compared with each of the U.S. race groups. The annual mortality rates for the Beijing patients were 99.4, 80.6, and 94.3 when adjusted to whites, African Americans, and Asian-Americans, respectively, in 2009.
Dr. Zuo’s group noted that the Beijing cohort was relatively younger than the USRDS cohort and had a lower prevalence of diabetic end-stage renal disease (ESRD). Regardless of age group, U.S. patients suffered from relatively higher mortality compared with their Beijing counterparts. The survival advantage of the Beijing cohort still persisted even after adjusting for age, gender, and primary cause of ESRD.
“Although the possibility of baseline comorbidity differences as an explanation for survival difference could not be ruled out, differences in practice pattern (such as time spent on patients by physicians) or race should be the main explanation,” the investigators wrote.
They pointed out that, according to the Dialysis Outcomes and Practice Patterns Study (DOPPS), better care was not explained by doses of erythropoiesis-stimulating agents or urea kinetics, but by the number of minutes physicians spent with their patients.
In Beijing, the authors explained, it is mandatory for physicians to be present in the dialysis facility when patients are undergoing dialysis. Physicians are asked to see patients before dialysis starts and to change their dialysis prescription if necessary. They are also asked to make ward rounds to contact each patient, and to see patients again to evaluate the finished dialysis session and make necessary dialysis prescription changes for the next dialysis session.
“To our knowledge, whether this practice pattern of intensive patient care favored better patient outcome has not been explored adequately,” the authors observed.