Dietary Protein Intake in a Multi-ethnic Asian Population of Healthy Participants and Chronic Kidney Disease Patients

<p><b>INTRODUCTION</b>Clinical practice guidelines recommend different levels of dietary protein intake in predialysis chronic kidney disease (CKD) patients. It is unknown how effectively these recommendations perform in a multi-ethnic Asian population, with varied cultural beliefs and diets. We assess the profi le of protein intake in a multi-ethnic Asian population, comparing healthy participants and CKD patients.</p><p><b>MATERIALS AND METHODS</b>We analysed the 24-hour urine collections of the Asian Kidney Disease Study (AKDS) and the Singapore Kidney Function Study (SKFS) to estimate total protein intake (TPI; g/day). We calculated ideal body weight (IDW; kg): 22.99 × height2 (m). Standard statistical tests were applied where appropriate, and linear regression was used to assess associations of continuous variables with protein intake.</p><p><b>RESULTS</b>There were 232 CKD patients and 103 healthy participants with 35.5% diabetics. The mean TPI in healthy participants was 58.89 ± 18.42 and the mean TPI in CKD patients was 53.64 ± 19.39. By US National Kidney Foundation (NKF) guidelines, 29/232 (12.5%) of CKD patients with measured glomerular filtration rate (GFR) <25 (in mL/min/1.73 m2) had a TPI-IDW of <0.6 g/kg/day. By Caring for Australasians with Renal Impairment (CARI) guidelines, 76.3% (177/232) of CKD patients had TPI-IDW >0.75g/kg/ day. By American Dietetic Association (ADA) guidelines, 34.7% (44/127) of CKD patients with GFR <50 had TPI-IDW between 0.6 to 0.8 g/kg/day. Only 1/6 non-diabetic CKD patients with GFR <20 had a protein intake of between 0.3 to 0.5 g/kg/day. A total of 21.9% (25/114) of diabetic CKD patients had protein intake between 0.8 to 0.9 g/kg/day.</p><p><b>CONCLUSION</b>On average, the protein intake of most CKD patients exceeds the recommendations of guidelines. Diabetic CKD patients should aim to have higher protein intakes.</p>

Dietary sodium intake in a multiethnic Asian population of healthy participants and chronic kidney disease patients

<p><b>INTRODUCTION</b>Clinical practice guidelines recommend using creatinine-based equations to estimate glomerular filtration rates (GFRs). While these equations were formulated for Caucasian-American populations and have adjustment coefficients for African-American populations, they are not validated for other ethnicities. The Chronic Kidney Disease-Epidemiology Collaborative Group (CKD-EPI) recently developed a new equation that uses both creatinine and cystatin C. We aimed to assess the accuracy of this equation in estimating the GFRs of participants (healthy and with chronic kidney disease [CKD]) from a multiethnic Asian population.</p><p><b>METHODS</b>Serum samples from the Asian Kidney Disease Study and the Singapore Kidney Function Study were used. GFR was measured using plasma clearance of 99mTc-DTPA. GFR was estimated using the CKD-EPI equations. The performance of GFR estimation equations were examined using median and interquartile range values, and the percentage difference from the measured GFR.</p><p><b>RESULTS</b>The study comprised 335 participants (69.3% with CKD; 38.5% Chinese, 29.6% Malays, 23.6% Indians, 8.3% others), with a mean age of 53.5 ± 15.1 years. Mean standardised serum creatinine was 127 ± 86 μmol/L, while mean standardised serum cystatin C and mean measured GFR were 1.43 ± 0.74 mg/L and 67 ± 33 mL/min/1.73 m2, respectively. The creatinine-cystatin C CKD-EPI equation performed the best, with an estimated GFR of 67 ± 35 mL/min/1.73 m2.</p><p><b>CONCLUSION</b>The new creatinine-cystatin C equation estimated GFR with little bias, and had increased precision and accuracy in our multiethnic Asian population. This two-biomarker equation may increase the accuracy of population studies on CKD, without the need to consider ethnicity.</p>

Performance of the CKD-EPI creatinine-cystatin C glomerular filtration rate estimation equations in a multiethnic Asian population

<p><b>INTRODUCTION</b>Clinical practice guidelines recommend using creatinine-based equations to estimate glomerular filtration rates (GFRs). While these equations were formulated for Caucasian-American populations and have adjustment coefficients for African-American populations, they are not validated for other ethnicities. The Chronic Kidney Disease-Epidemiology Collaborative Group (CKD-EPI) recently developed a new equation that uses both creatinine and cystatin C. We aimed to assess the accuracy of this equation in estimating the GFRs of participants (healthy and with chronic kidney disease [CKD]) from a multiethnic Asian population.</p><p><b>METHODS</b>Serum samples from the Asian Kidney Disease Study and the Singapore Kidney Function Study were used. GFR was measured using plasma clearance of 99mTc-DTPA. GFR was estimated using the CKD-EPI equations. The performance of GFR estimation equations were examined using median and interquartile range values, and the percentage difference from the measured GFR.</p><p><b>RESULTS</b>The study comprised 335 participants (69.3% with CKD; 38.5% Chinese, 29.6% Malays, 23.6% Indians, 8.3% others), with a mean age of 53.5 ± 15.1 years. Mean standardised serum creatinine was 127 ± 86 μmol/L, while mean standardised serum cystatin C and mean measured GFR were 1.43 ± 0.74 mg/L and 67 ± 33 mL/min/1.73 m2, respectively. The creatinine-cystatin C CKD-EPI equation performed the best, with an estimated GFR of 67 ± 35 mL/min/1.73 m2.</p><p><b>CONCLUSION</b>The new creatinine-cystatin C equation estimated GFR with little bias, and had increased precision and accuracy in our multiethnic Asian population. This two-biomarker equation may increase the accuracy of population studies on CKD, without the need to consider ethnicity.</p>

How can we improve clinical research in clinical practice with better research outcome?

This paper explains some of the difficulties doctors face when taking up a career in research. It describes the efforts by the government and the Ministry of Health (MOH) to nurture the Clinician Scientist Programme. The nature of research and the mindset of clinicians who are passionate about research are explored and the reasons which drive some of them to pursue a research career. It discusses the need to have structured training for research and how continuing research education is necessary for the researcher. The paper discusses the goals for research and how we can achieve better research outcomes and the importance of good mentorship. It suggests ways to engage more doctors in research in the restructured hospitals by overcoming some of the problems they encounter. Finally, it relates the Biomedical Science initiative of the government through the National Research Foundation and the various programmes in Translational Clinical Research available for clinicians who are keen on a research career.

3rd College of Physicians' lecture--translational research: From bench to bedside and from bedside to bench; incorporating a clinical research journey in IgA nephritis (1976 to 2006)

Translational research (TR) can be defined as research where a discovery made in the laboratory (bench) can be applied in the diagnosis, treatment or prevention of a disease. Examples of medical discoveries contributing to translational medicine (TM) include the isolation of insulin by Banting (Nobel Laureate, 1923), the discovery of penicillin by Alexander Fleming (Nobel Laureate, 1945) and recently the discovery of the role of bacterium Helicobacter pylori in the causation of gastritis and peptic ulcer by Marshall and Warren (Nobel Laureates, 2005). Clinical research (CR) would be a more appropriate term for the bulk of research work undertaken by doctors. CR embraces both clinical based and laboratory-based research. The terminology "bedside to bench" applies more to CR as opposed to "bench to bedside" in the case of TR. But regardless of who does it, as long as the discovery can be translated to the bedside and results in improvement in patient care it can be considered a contribution to TM. Our work spans a 30-year period, involving laboratory-based research, clinical trials and genomics of IgA nephritis (Nx). This is a series of work to elucidate the pathogensis and therapy of IgANx. Plasma beta-thromboglobulin (BTG) an in-vivo index of platelet aggregation and anti-thrombin III increase due to a constant thrombogenecity resulting from platelet degranulation formed the basis for anti-platelet and low-dose warfarin therapy. A study of the natural history of IgANx revealed 2 courses, a slowly progressive course with end-stage renal failure (ESRF) at 7.7 years and a more rapid course at 3.3 years. Triple therapy (cyclophosphamide, persantin and low-dose warfarin) delayed progression to ESRF by about 8 years and for some patients up to 20 years. Documentation of abnormal suppressor T cell function provided the basis for immune therapy. Four patterns of proteinuria were present in IgANx and it is the quality and not so much the quantity of proteinuria which determined the prognosis. Low molecular weight proteinuria was a bad prognostic marker. A controlled therapeutic trial using ACEI/ATRA showed that therapy decreases proteinuria, improves renal function and converts non-selective to selective proteinuria. Subsequent work confirmed that it was the ATRA, not the ACEI which contributed to improved renal function. Individual anti proteinuria response to ATRA varies depending on ACE gene polymorphism. We found that the II genotype of the ACE gene was renoprotective and patients with this genotype had significantly reduced incidence of ESRF compared to those with the DD genotype. Patients responsive to ATRA therapy can retard progression to ESRF by up to 32 years. Mild renal failure can be reversed with possible regression of glomerulosclerosis because of glomerular remodelling by ATRA.