Ling-I Chen

The ratio of observed to predicted left ventricular mass is independently associated with increased cardiovascular events in patients with chronic kidney disease.

A condition involving the growth of the myocardium that exceeds hemodynamic needs has been reported and called as inappropriate left ventricular mass (LVM). The appropriateness of LVM can be estimated by the ratio of observed LVM to predicted LVM. The excessive growth of LVM is frequently noted in patients with chronic kidney disease (CKD). This study is designed to assess whether the ratio of observed to predicted LVM is a useful prognostic indicator of cardiovascular events in patients with moderate to advanced CKD. We consecutively enrolled 485 patients with CKD stages 3–5 from our Outpatient Department of Internal Medicine. Inappropriate LVM was defined as observed LVM more than 28% greater than the predicted value. The relative risk of cardiovascular events was analyzed by Cox-regression methods. There was a significant trend for a stepwise increase in the observed/predicted LVM ratio (P<0.001) and the prevalence of inappropriate LVM (P=0.003) corresponding to advances in CKD stages. In the multivariate analysis, old age, a history of coronary artery disease, congestive heart failure, atrial fibrillation, wide pulse pressure, decreased serum albumin and hemoglobin levels, left atrial diameter >4.7 cm and increased observed/predicted LVM were independently associated with increased cardiovascular events. Our findings show that increased observed/predicted LVM is independently associated with adverse cardiovascular outcomes in patients with CKD stages 3–5.

Modification of diet in renal disease (MDRD) study and CKD epidemiology collaboration (CKD-EPI) equations for Taiwanese adults.

Background Estimated glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease (MDRD) study or the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations may not be accurate for Asians; thus, we developed modified eGFR equations for Taiwanese adults. Methods This cross-sectional study compared the Taiwanese eGFR equations, the MDRD study, and the CKD-EPI equations with inulin clearance (Cin). A total of 695 adults including 259 healthy volunteers and 436 CKD patients were recruited. Participants from the Kaohsiung Medical University Hospital were used as the development set (N = 556) to develop the Taiwanese eGFR equations, whereas participants from the National Taiwan University Hospital were used as the validation set (N = 139) for external validation. Results The Taiwanese eGFR equations were developed by using the extended Bland-Altman plot in the development set. The Taiwanese MDRD equation was 1.309×MDRD0.912, Taiwanese CKD-EPI was 1.262×CKD-EPI0.914 and Taiwanese four-level CKD-EPI was 1.205×four-level CKD-EPI0.914. In the validation set, the Taiwanese equations had the lowest bias, the Taiwanese equations and the Japanese CKD-EPI equation had the lowest RMSE, whereas the Taiwanese and the Japanese equations had the best precision and the highest P30 among all equations. However, the Taiwanese MDRD equation had higher concordance correlation than did the Taiwanese CKD-EPI, the Taiwanese four-level CKD-EPI and the Japanese equations. Moreover, only the Taiwanese equations had no proportional bias among all of the equations. Finally, the Taiwanese MDRD equation had the best diagnostic performance in terms of ordinal logistic regression among all of the equations. Conclusion The Taiwanese MDRD equation is better than the MDRD, CKD-EPI, Japanese, Asian, Thai, Taiwanese CKD-EPI, and Taiwanese four-level CKD-EPI equations for Taiwanese adults.

The rs1014290 Polymorphism of the SLC2A9 Gene Is Associated with Type 2 Diabetes Mellitus in Han Chinese

Aims. The SLC2A9 gene encodes the glucose transporter 9, with the abilities of transporting both glucose and uric acid and is involved in the pancreatic glucose-stimulated insulin secretion. The single nucleotide polymorphisms (SNPs) of SLC2A9 accounted for 5% variance of serum uric acid (UA). UA was identified as a risk factor for type 2 diabetes mellitus (DM). We investigated whether the SLC2A9 gene variations are associated with type 2 DM in Han Chinese. Methods. Three common SNPs of the SLC2A9, rs1014290, rs2280205, and rs3733591, were genotyped in 1003 Han Chinese randomly selected from Kaohsiung, Taiwan. Results. The variant SNP rs1014290 is associated with decreased 0.12-fold risk of type 2 DM (P = .002). Per-copy increase in the minor C-allele results in 0.13 mmol/L (P = .037) and 10.03 μmol/L (P = .016) decrease in serum glucose and UA, respectively. Conclusions. The SNP rs1014290 within the SLC2A9 gene is associated with type 2 DM in Han Chinese.

Ratio of transmitral E-wave velocity to early diastole mitral annulus velocity with cardiovascular and renal outcomes in chronic kidney disease.

Background/Aims: Impaired left ventricular diastolic function and increased left ventricular filling pressure are frequently noted in patients with chronic kidney disease (CKD), even in early stages. The association of increased left ventricular filling pressure with cardiovascular and renal outcomes remains uncertain in CKD. This study is designed to assess whether the ratio of transmitral E-wave velocity (E) to early diastole mitral velocity (Ea) is associated with cardiovascular events and progression to dialysis in patients with CKD stages 3-5. Methods: This longitudinal study enrolled 356 predialysis CKD patients. Cardiovascular events were defined as cardiovascular death, hospitalization for unstable angina, nonfatal myocardial infarction, ventricular tachycardia, hospitalization for congestive heart failure, transient ischemia attack, and stroke. The renal endpoint was defined as commencement of dialysis. The relative cardiovascular events and renal endpoints risks were analyzed by Cox regression methods. Results: The high E/Ea was independently associated with old age, cerebrovascular disease, congestive heart failure, high systolic blood pressure, hypertriglyceridemia, low hemoglobin, proteinuria, and worse echocardiographic profiles. Besides, the high E/Ea increased the risk of cardiovascular events (hazard ratio (HR) 1.067; 95% confidence interval (CI) 1.017-1.119; p = 0.008) and progression to dialysis (HR 1.042; 95% CI 1.000-1.085; p = 0.048). Conclusions: Our study in patients of CKD stages 3-5 demonstrated the high E/Ea was associated with increased cardiovascular events and progression to dialysis. Assessment of the E/Ea by Doppler echocardiography is useful for predicting the risk of adverse cardiovascular and renal outcomes in CKD patients.

Significant correlation between ratio of brachial pre-ejection period to ejection time and left ventricular ejection fraction and mass index in patients with chronic kidney disease

BACKGROUND Patients with chronic kidney disease (CKD) are associated with increased cardiovascular morbidity and mortality. An increase in the ratio of pre-ejection period (PEP) to ejection time (ET) is correlated with an increase in left ventricular mass index (LVMI) and a decrease in left ventricular ejection fraction (LVEF). Brachial PEP (bPEP) and brachial ET (bET) can be automatically determined by an ankle-brachial index (ABI)-form device. The aims of this study were to assess whether bPEP/bET is a useful parameter in evaluation of LVMI and LVEF in patients with CKD and to evaluate the diagnostic value of bPEP/bET in the prediction of LVEF < 50%. METHODS We consecutively enrolled 234 CKD patients from our Outpatient Department of Internal Medicine. Both bPEP and bET were measured using an ABI-form device. Clinical and echocardiographic parameters were compared and analysed. RESULTS Multivariate analysis results show that bPEP/bET, systolic blood pressure, and body mass index were positively while albumin was negatively associated with LVMI. In addition, increased bPEP/bET, coronary artery disease, decreased albumin, and increased triglyceride were independent factors associated with decreased LVEF. The area under the curve for bPEP/bET in the prediction of LVEF < 50% was 0.859. CONCLUSIONS Our findings show that bPEP/bET is an important determinant of LVMI and LVEF in CKD patients. It is also helpful in identification of CKD patients with LVEF < 50%. Screening CKD patients by means of bPEP/bET may help identify a high risk group of increased LVMI and decreased LVEF.

Association of P-Wave Dispersion with Overall and Cardiovascular Mortality in Hemodialysis Patients

Background/Aims: The P-wave parameters that are measured using a 12-lead electrocardiogram are commonly used as noninvasive tools for assessing left atrial enlargement. This study was designed to assess whether P-wave dispersion is associated with overall and cardiovascular mortality in hemodialysis patients. Methods: This study enrolled 209 hemodialysis patients. We measured the P-wave dispersion corrected by heart rate, that is, the corrected P-wave dispersion (PWdisperC), and assessed its correlation with overall and cardiovascular mortalities. Results: The mean PWdisperC of all the patients was 93.3 ± 21.1 ms. During the follow-up period (mean 5.4 years), 58 deaths and 37 cardiovascular deaths were recorded. The adjusted value of PWdisperC was also associated with overall (hazards ratio (HR) 1.018, 95% CI 1.004-1.033, p = 0.014) and cardiovascular (HR 1.032, 95% CI 1.012-1.053, p = 0.002) mortalities. Multivariate Cox regression analysis identified tertile 3 of PWdisperC (vs. tertile 1) to be associated with overall (HR 2.472, 95% CI 1.181-5.174, p = 0.016) and cardiovascular (HR 3.896, 95% CI 1.463-10.376, p = 0.007) mortalities, after adjustment for demographic, clinical and biochemical parameters. Adding PWdisperC to a model of clinical features could significantly improve the predictive value for overall (p = 0.044) and cardiovascular (p = 0.002) mortalities. Conclusions: We concluded that PWdisperC was positively associated with overall and cardiovascular mortalities in hemodialysis patients and could provide additional prognostic values. Screening hemodialysis patients by using PWdisperC may facilitate identifying a group of patients with poor prognosis.

Body Mass Index, Left Ventricular Mass Index and Cardiovascular Events in Chronic Kidney Disease

Background Obesity and left ventricular hypertrophy are prevalent in chronic kidney disease (CKD), but the association of body mass index (BMI) and left ventricular mass index (LVMI) with cardiovascular outcomes in patients with CKD is unclear. This study was designed to assess whether the combination of BMI and LVMI is independently associated with cardiovascular events in patients with CKD stages 3‐5. Methods From the outpatient department, 523 patients with CKD who received echocardiographic examination were enrolled. The patients under study were classified into 4 groups according to sex‐specific median BMIs and LVMIs. Cardiovascular events were defined as cardiovascular death, hospitalization for unstable angina, nonfatal myocardial infarction, sustained ventricular arrhythmia, hospitalization for congestive heart failure, transient ischemia attack and stroke. The relative cardiovascular event risk was analyzed using Cox‐regression methods. Results The patients were stratified into 4 groups according to sex‐specific median BMIs (men: 25.2 kg/m2; women: 24.9 kg/m2) and LVMIs (men: 140.1 g/m2; women: 131.6 g/m2). A combination of low BMI and high LVMI (versus the combination of high BMI and low LVMI) was significantly associated with cardiovascular events in an unadjusted model (hazard ratio [HR] = 3.178; 95% confidence interval [CI]: 1.645‐6.140; P < 0.001) and in a multivariable model after adjustment for demographic, clinical and biochemical characteristics and medications (HR = 3.553; 95% CI: 1.494‐8.450; P = 0.004). Conclusions The findings showed that the combination of low BMI and high LVMI was associated with adverse cardiovascular events in patients with CKD stages 3–5.

Association between albumin and C-reactive protein and ankle-brachial index in haemodialysis: Albumin, CRP and ABI in HD

Peripheral artery occlusive disease (PAOD) is associated with increased rates of cardiovascular mortality, morbidity and hospitalization in patients undergoing dialysis. An ankle‐brachial index (ABI) less than 0.9 has been used to diagnose PAOD. The aim of this study was to evaluate associations among inflammation, malnutrition and their interactions on the risk of PAOD.

Type 2 diabetes mellitus-related changes in left ventricular structure and function in patients with chronic kidney disease

Type 2 Diabetes mellitus (DM) is the leading cause of chronic kidney disease (CKD) worldwide, and is associated with an increased risk of left ventricular (LV) hypertrophy, LV systolic and diastolic dysfunctions. The aim of this study was to investigate abnormal echocardiographic findings in patients with CKD with and without DM, and identify the factors associated with these abnormalities. We enrolled 356 pre-dialysis patients with CKD (stages 3–5), including 208 with DM and 148 without DM. The structure and systolic and diastolic functions of the left ventricle were assessed using echocardiography, and the clinical and echocardiographic parameters were analyzed. The patients with DM had higher rates of observed/predicted left ventricular mass > 128% (69.5% vs. 56.7%, p = 0.015), midwall fractional shortening < 14% (22.6% vs. 8.8%, p = 0.001), and ratio of peak early transmitral filling wave velocity to early diastolic velocity of lateral mitral annulus > 12 (32.7% vs. 16.2%, p < 0.001) than those without DM. Multivariate analysis showed that male sex, a history of smoking, high systolic blood pressure, high body mass index, high levels of fasting glucose and total cholesterol, low levels of albumin and hemoglobin, and a low estimated glomerular filtration rate were associated with abnormal echocardiographic findings. The rates of inappropriate left ventricular mass, systolic and diastolic dysfunction were higher in our patients with CKD and DM than in those without DM.