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Adequacy Targets of Peritoneal Dialysis in the Asian Population

End-stage renal disease affects a large number of patients in Asia. The percentage of patients utilizing PD varies significantly in Asian countries. Continuous ambulatory peritoneal dialysis (CAPD) accounts for about 80% of the dialysis population in Hong Kong.

In this review, we address several questions related to adequacy targets in Asians: Are Asians different? Is dialysis adequacy important for Asians? What is the magnitude of the benefit and the optimal dose of dialysis prescription? Is the adequacy target realistic?

The current international recommendations, including the Dialysis Outcomes Quality Initiative guidelines, are compared with some of our own data for Asian patients. Our published data on dialysis adequacy, nutrition, residual renal function, and peritoneal membrane transport showed that those factors have a significant impact on the morbidity and mortality of PD patients in Hong Kong.

Our results show that solute clearance as measured by Kt/V has a significant impact on the outcome of Asian CAPD patients. Although Chinese PD patients have excellent medium-term patient and technique survival despite an apparently lower Kt/V as compared with the CANUSA standard, that favorable outcome should not prevent nephrologists from providing adequate dialysis to Asian patients. From our own data and analysis, we propose a target Kt/V of 1.9 in Asian CAPD populations. Small-volume dialysis (6 L daily) may be an acceptable compromise in some Asian populations with a smaller body size, especially with residual renal function, given the financial constraints in some developing countries.

Dialysis adequacy means more than a Kt/V value; other clinical parameters are equally if not more important. Thus we should also aim at achieving adequate fluid removal and volume homeostasis, blood pressure control, good nutrition, normal acid–base balance, normal mineral metabolism, minimal anemia, and normal lipid metabolism.

Predictors of diabetic end-stage renal disease in Japan

Diabetes mellitus (DM) has been the leading cause of incident dialysis in Japan since 1998, according to the Japanese Society for Dialysis Therapy (JSDT). In particular, the number of male DM dialysis patients is increasing. DM is becoming a worldwide epidemic in both developed and developing countries. Strategies to detect individuals at high-risk of developing CKD and end-stage renal disease (ESRD) are needed that can be implemented on a population-basis. Among the commonly measured variables, dipstick urinalysis (proteinuria, haematuria), blood pressure, serum creatinine, body mass index (BMI), and serum uric acid are significant predictors of ESRD. Recently, we evaluated the effect of DM as a risk factor of developing ESRD. DM was diagnosed when the fasting plasma glucose (FPG) was 126 mg/dL or more in participants (n = 78529) of the 1993 screening program in Okinawa. The prevalence of DM was 5.2%. The odds ratio (95% CI) of DM for developing ESRD was 3.098 (1.738-5.525, P = 0.0001) after adjusting for possible confounding variables. Early detection and treatment of DM might prevent DM-related ESRD. We examined 7125 non-DM screenees who underwent a 1-day health check between April 1997 and March 1998. They were followed-up until March 2000 to determine whether they developed DM. Over the 2 years, the cumulative incidence of DM was 2.3%, 2.9% in men and 1.3% in women. Proteinuria was the most robust predictor of the development of DM; the adjusted relative risk (95% CI) was 1.90 (1.14-3.17). Obesity, per se, is also recognized as a risk factor for developing proteinuria. The higher the BMI, the higher the risk of developing ESRD; the adjusted odds ratio (95% CI) was 1.273 (1.121-1.446, P = 0.0002) for men. Other than being overweight (BMI = 25.0 kg/m2), a smoking habit was a significant predictor of developing proteinuria. The prevalence of obesity and DM is increasing in Japan. It is possible that the impact of obesity and complications of DM are different among races and ethnicities. Public relations regarding the risk of DM and its complications are especially important in Asian countries. Asians have more fat than non-Asians, even at the same BMI levels. Knowledge of the predictors of DM-ESRD is crucial as a first step toward prevention. Consistent with this notion, initiatives on the management of CKD and ESRD were recently organized in Japan and internationally.