Association of age and BP variability with long-term mortality in hemodialysis patients.

BACKGROUND/AIMS: Blood pressure (BP) variability is known as a poor prognostic factor for cardiovascular outcomes. This study assessed the prognostic significance of BP variability in association with increasing age in hemodialysis patients. METHODS: We retrospectively analyzed 2,174 patients on hemodialysis from March 2005 to December 2012. The impact of intradialytic and interdialytic BP variability on all-cause mortality according to age groups was analyzed. RESULTS: Kaplan-Meier survival curves for 5-year cumulative mortality showed higher mortality in patients with higher intradialytic systolic and diastolic BP variability as well as interdialytic systolic and diastolic BP variability (log-rank p=0.006, <0.001, 0.018 and < 0.001) in patients aged <55 years, but not in older age groups. Cox proportional analysis revealed that 5-year mortality was associated with intradialytic diastolic BP variability in patients aged <55 years (HR, 2.03 CI, 1.24-3.32). CONCLUSION: The overall mortality was associated with BP variability in patients aged <55 years, but not in older ages. This result suggests that younger hemodialysis patients with BP variability require further medical attention and intervention to reduce BP variability.

Influence of renal dysfunction on clinical outcomes in patients with congestive heart failure complicating acute myocardial infarction.

The clinical course and medical treatment of patients with congestive heart failure (CHF) complicating acute myocardial infarction (AMI) are not well established, especially in patients with concomitant renal dysfunction. We performed a retrospective analysis of the prospective Korean Acute Myocardial Infarction Registry to assess the medical treatments and clinical outcomes of patients with CHF (Killip classes II or III) complicated by AMI, in the presence or absence of renal dysfunction. Of 13,498 patients with AMI, 2769 (20.5%) had CHF on admission. Compared to CHF patients with preserved renal function, in-hospital mortality and major adverse cardiac events were increased both at 1 month and at 1 year after discharge in patients with renal dysfunction (1154; 41.7%). Postdischarge use of aspirin, betablockers, calcium channel blockers, angiotensin-converting enzyme inhibitors, or angiotensin II receptor blockers and statins significantly reduced the 1-year mortality rate for CHF patients with renal dysfunction; such reduction was not observed for those without renal dysfunction, except in the case of aspirin. Patients with CHF complicating AMI, which is accompanied by renal dysfunction, are at higher risk for adverse cardiovascular outcomes than patients without renal dysfunction. However, they receive fewer medications proven to reduce mortality rates.

Determinants and burden of chronic kidney disease in a high-risk population in Korea: results from a cross-sectional study.

BACKGROUND/AIMS: This study aimed to investigate the prevalence of chronic kidney disease (CKD) and associated risk factors in a high-risk population in Korea. METHODS: A total of 6,045 participants aged ≥ 65 years (mean age, 73.0 ± 5.5) with diabetes or hypertension were enrolled. Participants were screened for CKD, which was defined as the presence of albuminuria (urine albumin-to-creatinine ratio ≥ 30 mg/g) or an estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m(2). RESULTS: The prevalence of CKD was 39.6% (women, 40.3%; men, 38.4%). Albuminuria was detected in 22.6% of participants, whereas eGFR < 60 mL/min/1.73 m(2) was found in 24.6% of participants. The prevalence of CKD by stage was 4.4% for stage 1, 10.4% for stage 2, 23.4% for stage 3, 0.9% for stage 4, and 0.3% for stage 5. Older age, concomitant diabetes and hypertension, higher body mass index, higher systolic and diastolic blood pressure, and higher hemoglobin A1c levels were independently associated with the presence of CKD in multivariate-adjusted analyses that included with age, sex, body mass index, hypertension, diabetes, and smoking. CONCLUSIONS: The prevalence of CKD was very high in the present high-risk Korean population. Our results suggest that a screening method for early detection of CKD in high-risk populations is needed in Korea.

Risk factors for in-hospital mortality in patients starting hemodialysis.

BACKGROUND: Incident hemodialysis patients have the highest mortality in the first several months after starting dialysis. This study evaluated the in-hospital mortality rate after hemodialysis initiation, as well as related risk factors. METHODS: We examined in-hospital mortality and related factors in 2,692 patients starting incident hemodialysis. The study population included patients with acute kidney injury, acute exacerbation of chronic kidney disease, and chronic kidney disease. To determine the parameters associated with in-hospital mortality, patients who died in hospital (nonsurvivors) were compared with those who survived (survivors). Risk factors for in-hospital mortality were determined using logistic regression analysis. RESULTS: Among all patients, 451 (16.8%) died during hospitalization. The highest risk factor for in-hospital mortality was cardiopulmonary resuscitation, followed by pneumonia, arrhythmia, hematologic malignancy, and acute kidney injury after bleeding. Albumin was not a risk factor for in-hospital mortality, whereas C-reactive protein was a risk factor. The use of vancomycin, inotropes, and a ventilator was associated with mortality, whereas elective hemodialysis with chronic kidney disease and statin use were associated with survival. The use of continuous renal replacement therapy was not associated with in-hospital mortality. CONCLUSION: Incident hemodialysis patients had high in-hospital mortality. Cardiopulmonary resuscitation, infections such as pneumonia, and the use of inotropes and a ventilator was strong risk factors for in-hospital mortality. However, elective hemodialysis for chronic kidney disease was associated with survival.

Metabolic syndrome and chronic kidney disease in an adult Korean population: results from the Korean National Health Screening.

BACKGROUND: This study was aimed to examine the prevalence of metabolic syndrome (MS) and chronic kidney disease (CKD), and the association between MS and its components with CKD in Korea. METHODS: We excluded diabetes to appreciate the real impact of MS and performed a cross-sectional study using the general health screening data of 10,253,085 (48.86 ± 13.83 years, men 56.18%) participants (age, ≥ 20 years) from the Korean National Health Screening 2011. CKD was defined as dipstick proteinuria ≥ 1 or an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m(2). RESULTS: The prevalence of CKD was 6.15% (men, 5.37%; women, 7.15%). Further, 22.25% study population had MS (abdominal obesity, 27.98%; hypertriglyceridemia, 30.09%; low high-density cholesterol levels, 19.74%; high blood pressure, 43.45%; and high fasting glucose levels, 30.44%). Multivariate-adjusted analysis indicated that proteinuria risk increased in participants with MS (odds ratio [OR] 1.884, 95% confidence interval [CI] 1.867-1.902, P<0.001). The presence of MS was associated with eGFR<60 mL/min/1.73 m(2) (OR 1.364, 95% CI 1.355-1.373, P<0.001). MS individual components were also associated with an increased CKD risk. The strength of association between MS and the development of CKD increase as the number of components increased from 1 to 5. In sub-analysis by men and women, MS and its each components were a significant determinant for CKD. CONCLUSIONS: MS and its individual components can predict the risk of prevalent CKD for men and women.

Association of pulse wave velocity and pulse pressure with decline in kidney function.

The association between arterial stiffness and decline in kidney function in patients with mild to moderate chronic kidney disease (CKD) is not well established. This study investigated whether pulse wave velocity (PWV) and pulse pressure (PP) are independently associated with glomerular filtration rate (GFR) and rapid decline in kidney function in early CKD. Carotid femoral PWV (cfPWV), brachial-ankle PWV (baPWV), and PP were measured in a cohort of 913 patients (mean age, 63±10 years; baseline estimated GFR, 84±18 mL/min/1.73 m(2) ). Estimated GFR was measured at baseline and at follow-up. The renal outcome examined was rapid decline in kidney function (estimated GFR loss, >3 mL/min/1.73 m(2) per year). The median follow-up duration was 3.2 years. Multivariable adjusted linear regression model indicated that arterial PWV (both cfPWV and baPWV) and PP increased as estimated GFR declined, but neither was associated with kidney function after adjustment for various covariates. Multivariable logistic regression analysis found that cfPWV and baPWV were not associated with rapid decline in kidney function (odds ratio [OR], 1.39, 95% confidence interval [CI], 0.41-4.65; OR, 2.51, 95% CI, 0.66-9.46, respectively), but PP was (OR, 1.22, 95% CI, 1.01-1.48; P=.045). Arterial stiffness assessed using cfPWV and baPWV was not correlated with lower estimated GFR and rapid decline in kidney function after adjustment for various confounders. Thus, PP is an independent risk factor for rapid decline in kidney function in populations with relatively preserved kidney function (estimated GFR ≥30 mL/min/1.73 m(2) ).

Concomitant impact of high-sensitivity C-reactive protein and renal dysfunction in patients with acute myocardial infarction.

PURPOSE: The present study aimed to investigate the impact of high-sensitivity C-reactive protein (hs-CRP) and renal dysfunction on clinical outcomes in acute myocardial infarction (AMI) patients. MATERIALS AND METHODS: The study involved a retrospective cohort of 8332 patients admitted with AMI. The participants were divided into 4 groups according to the levels of estimated glomerular filtration rate (eGFR) and hs-CRP: group I, no renal dysfunction (eGFR ≥60 mL·min(-1)·1.73 m(-2)) with low hs-CRP (≤2.0 mg/dL); group II, no renal dysfunction with high hs-CRP; group III, renal dysfunction with low hs-CRP; and group IV, renal dysfunction with high hs-CRP. We compared major adverse cardiac events (MACE) over a 1-year follow-up period. RESULTS: The 4 groups demonstrated a graded association with increased MACE rates (group I, 8.8%; group II, 13.8%; group III, 18.6%; group IV, 30.1%; p<0.001). In a Cox proportional hazards model, mortality at 12 months increased in groups II, III, and IV compared with group I [hazard ratio (HR) 2.038, 95% confidence interval (CI) 1.450-2.863, p<0.001; HR 3.003, 95% CI 2.269-3.974, p<0.001; HR 5.087, 95% CI 3.755-6.891, p<0.001]. CONCLUSION: High hs-CRP, especially in association with renal dysfunction, is related to the occurrence of composite MACE, and indicates poor prognosis in AMI patients.

Relation of serum potassium level to long-term outcomes in patients with acute myocardial infarction.

Potassium plays a key role in normal myocardial function, and current guidelines recommend that serum potassium levels be maintained from 4.0 to 5.0 mEq/L in patients with acute myocardial infarction (AMI). However, the impact of serum potassium levels on long-term mortality has not been evaluated. We retrospectively studied 1,924 patients diagnosed with AMI. The average serum potassium levels measured throughout the hospitalization were obtained and statistically analyzed. Patients were categorized into 5 groups to determine the relation between mean serum potassium and long-term mortality: <3.5, 3.5 to <4.0, 4.0 to <4.5, 4.5 to <5.0, and ≥5 mEq/L. The long-term mortality was lowest in the group of patients with potassium levels of 3.5 to <4.0 mEq/L, whereas mortality was higher in the patients with potassium levels≥4.5 or <3.5 mEq/L. In a multivariate Cox-proportional regression analysis, the mortality risk was greater for serum potassium levels of >4.5 mEq/L (hazard ratio [HR] 1.71, 95% confidence interval [CI] 1.04 to 2.81 and HR 4.78, 95% CI 2.14 to 10.69, for patients with potassium levels of 4.5 to <5.0 mEq/L and ≥5.0, respectively) compared with patients with potassium levels of 3.5 to <4.0 mEq/L. The mortality risk was also higher for patients with potassium levels<3.5 mEq/L (HR 1.55, 95% CI 0.94 to 2.56). In contrast to the association with long-term mortality, there was no relation between serum potassium levels and the occurrence of ventricular arrhythmias. The results of the current analysis suggest that there is a need for change in our current concepts of the ideal serum potassium levels in patients with AMI.

Incidence, predictive factors, and clinical outcomes of acute kidney injury after gastric surgery for gastric cancer.

BACKGROUND: Postoperative acute kidney injury (AKI), a serious surgical complication, is common after cardiac surgery; however, reports on AKI after noncardiac surgery are limited. We sought to determine the incidence and predictive factors of AKI after gastric surgery for gastric cancer and its effects on the clinical outcomes. METHODS: We conducted a retrospective study of 4718 patients with normal renal function who underwent partial or total gastrectomy for gastric cancer between June 2002 and December 2011. Postoperative AKI was defined by serum creatinine change, as per the Kidney Disease Improving Global Outcomes guideline. RESULTS: Of the 4718 patients, 679 (14.4%) developed AKI. Length of hospital stay, intensive care unit admission rates, and in-hospital mortality rate (3.5% versus 0.2%) were significantly higher in patients with AKI than in those without. AKI was also associated with requirement of renal replacement therapy. Multivariate analysis revealed that male gender; hypertension; chronic obstructive pulmonary disease; hypoalbuminemia (<4 g/dl); use of diuretics, vasopressors, and contrast agents; and packed red blood cell transfusion were independent predictors for AKI after gastric surgery. Postoperative AKI and vasopressor use entailed a high risk of 3-month mortality after multiple adjustments. CONCLUSIONS: AKI was common after gastric surgery for gastric cancer and associated with adverse outcomes. We identified several factors associated with postoperative AKI; recognition of these predictive factors may help reduce the incidence of AKI after gastric surgery. Furthermore, postoperative AKI in patients with gastric cancer is an important risk factor for short-term mortality.

Serratia marcescens Peritonitis in a Diabetic Patient Receiving Continuous Ambulatory Peritoneal Dialysis.

We report a case of Serratia marcescens peritonitis in a 45-year-old man with insulin-dependent diabetes mellitus undergoing continuous ambulatory peritoneal dialysis (CAPD). The patient presented with abdominal pain and cloudy dialysate. Empiric antibiotic therapy was initiated intraperitoneally with cefazolin and ceftazidime for 5 days. Cultures of the dialysate revealed S. marcescens, and the treatment was subsequently changed to gentamicin and ceftazidime. Oral ciprofloxacin was also added. The patient's abdominal pain and the dialysate white blood cell (WBC) count, however, did not improve. The indwelling CAPD catheter was therefore removed. This is an unusual case report in the Korean literature of S. marcescens peritonitis in a patient receiving CAPD.

Proteinuria as a risk factor for mortality in patients with colorectal cancer.

PURPOSE: We investigated the effects of proteinuria and renal insufficiency on all-cause mortality in patients with colorectal cancer, with special emphasis on cancer staging and cancer-related deaths. MATERIALS AND METHODS: We retrospectively studied a cohort of patients with colorectal cancer. In protocol 1, patients were classified into four groups based on the operability of cancer and proteinuria: group 1, early-stage cancer patients (colorectal cancer stage ≤ 3) without proteinuria; group 2, early-stage cancer patients with proteinuria; group 3, advanced-stage cancer patients without proteinuria (colorectal cancer stage=4); and group 4, advanced- stage cancer patients with proteinuria. In protocol 2, patients were classified into four similar groups based on cancer staging and renal insufficiency (eGFR <60 mL/min/1.73 m(2)). Between January 1, 1998 and December 31, 2009, 3379 patients were enrolled in this cohort and followed until May 1, 2012 or until death. RESULTS: The number of patients with proteinuria was 495 (14.6%). The prevalence of proteinuria was higher in advanced-stage cancer (n=151, 22.3%) than in early-stage cancer patients (n=344, 12.7%). After adjusting for age, gender and other clinical variables, the proteinuric, early-stage cancer group was shown to be associated with an adjusted hazard ratio of 1.67 and a 95% confidence interval of 1.38-2.01, compared with non-proteinuric early-stage cancer patients. However, renal insufficiency was not associated with colorectal cancer mortality. CONCLUSION: Proteinuria is an important risk factor for cancer mortality, especially in relatively early colorectal cancer.

Relation between transient or persistent acute kidney injury and long-term mortality in patients with myocardial infarction.

Limited information is available regarding the impact of acute kidney injury (AKI) during hospitalization on clinical outcomes after myocardial infarction (MI), and the effect of transient kidney injury (KI) on long-term mortality has not been validated. We retrospectively analyzed 2,289 patients diagnosed with MI. AKI patients were classified into a transient KI group and a persistent KI group based on serum creatinine levels at discharge. The end point of the study was 3-year mortality after MI. We included 2,110 patients of whom 237 patients (11%) developed AKI during hospitalization. Of these 237 patients, 154 (65%) had transient KI, and 83 (35%) had persistent KI. Multivariate analysis showed that age, left ventricular ejection fraction, estimated glomerular filtration rate on admission, and Killip class were significantly associated with developing AKI during hospitalization. The adjusted hazard ratios for 3-year mortality were 1.71 (95% confidence interval: 1.08-2.70) for AKI patients with transient KI and 2.21 (95% confidence interval: 1.34-3.64) for AKI patients with persistent KI, compared with no AKI. In conclusion, AKI was associated with an increased risk of death for patients who experienced MIs and survived during hospitalization. Although renal function had completely recovered in many AKI patients at discharge, these transient KI patients are also at a great risk of death after MI.

Clinical impact of hospital-acquired anemia in association with acute kidney injury and chronic kidney disease in patients with acute myocardial infarction.

BACKGROUND: Hospital-acquired anemia (HAA) is common in patients with acute myocardial infarction (AMI) and is an independent indicator of long-term mortality in these patients. However, limited information exists regarding the development and prognostic impact of HAA associated with acute kidney injury (AKI) and chronic kidney disease (CKD) in AMI patients. METHODS AND RESULTS: We retrospectively analyzed 2,289 patients with AMI, and excluded those with anemia at admission. The study population included 1,368 patients, of whom 800 (58.5%) developed HAA. Age, Hgb level at admission, Length of hospital stay, documented in-hospital bleeding and use of glycoprotein IIb/IIIa inhibitor, presence of CKD and occurrence of AKI were significantly associated with the development of HAA. HAA was significantly associated with higher 3-year mortality (4.8% and 11.4% for non-HAA and HAA patients, respectively; P < 0.001). After adjustment for multivariable confounders, the risk for long-term mortality was increased in HAA patients with AKI and/or CKD but not in HAA patients without AKI and/or CKD, compared to non-HAA patients (HAA patients without AKI and CKD, hazard ratio [HR]: 1.34, 95% confidence interval [CI]: 0.70-2.56; HAA patients with either AKI or CKD, HR: 2.80, 95% CI: 1.37-5.73; HAA patients with AKI and CKD, HR: 3.25, 95% CI: 1.28-8.24; compared with the non-HAA group). CONCLUSION: AKI and CKD were strongly associated with the development of HAA in AMI patients. HAA, when accompanied by AKI or CKD, is an independent risk predictor for long-term mortality in AMI patients.

Does gender influence the impact of impaired renal function on prognosis after ST-segment elevated myocardial infarction?

BACKGROUND: A limited number of studies have investigated the impact of gender on renal function and clinical outcomes after ST-segment elevated myocardial infarction (STEMI), and these studies have provided discrepant results. METHODS AND RESULTS: This study was based on a retrospective cohort, the Korean Acute Myocardial Infarction Registry (KAMIR). Patients (n = 7,679) with a discharge diagnosis of STEMI were analyzed to investigate association of gender with renal function and clinical outcomes. Compared to men, women were older and exhibited more comorbidity, including impaired renal function. Women showed higher mortality compared to men (1-month mortality,5.6% in men vs. 12.6% in women, p < 0.001; 1-year mortality, 6.8% in men vs. 14.4% in women, p < 0.001). The risk of death proportionally increased as estimated glomerular filtration rate (eGFR) decreased in both genders. After adjusting for potential confounders, hazard ratios for women did not significantly differ from those for men at each eGFR level.The interaction test showed no significant interaction between gender and eGFR in 1-month mortality and 1-year mortality. CONCLUSIONS: Impaired renal function was an independent prognostic factor after STEMI in both genders, and the impact of impaired renal function on prognosis after STEMI did not significantly differ between genders.

Association of age and CKD with prognosis of myocardial infarction.

BACKGROUND AND OBJECTIVES: CKD is a well known poor prognostic factor in myocardial infarction (MI). This study evaluated the prognostic significance of CKD, particularly in association with increasing age, in MI patients. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This study was based on a retrospective cohort, the Korean Acute Myocardial Infarction Registry. Patients with a discharge diagnosis of MI were analyzed to investigate the association of CKD with mortality risk according to age. A total of 11,268 patients (mean age 63.0±12.6 years) were included and followed for 1 year. RESULTS: In the full cohort, 26% of patients had CKD (n=2929). The prevalence of CKD was higher with advancing age. Eight hundred sixty-one patients (7.6%) died and the interaction for 1-year mortality between age strata and estimated GFR (eGFR) strata was significant (P<0.001). Within each age category, the absolute 1-year mortality was higher in patients with a low eGFR. However, the adjusted relative mortality risk for a low eGFR was lower with increasing age (adjusted hazard ratio [95% confidence interval] for 1-year mortality at eGFR <30 ml/min per 1.73 m(2): 4.84 [1.93-12.15], 4.53 [2.42-8.47], 3.51 [2.42-5.09], and 3.30 [2.41-4.52] for patients aged <55, 55-64, 65-74, and ≥75 years compared with those with eGFR ≥60 ml/min per 1.73 m(2), respectively). CONCLUSIONS: For all age categories, the overall mortality was significantly higher as eGFR declined. The association of a lower eGFR with mortality was weaker with increasing age, indicating that the prognostic significance of CKD in MI patients is age dependent.

Hypercalcemia in a patient with polycythemia vera.

A 59-year-old female with diabetes mellitus presented with hypercalcemia and polycythemia. Her serum calcium and intact parathyroid hormone (iPTH) levels were increased, and Tc-99m sesta-MIBI scanning showed hot uptake in the lower portion of the left thyroid lobe. After parathyroidectomy, her calcium, iPTH, and polycythemia were normalized. In conclusion, the differential diagnosis of polycythemia and hypercalcemia should also include the possibility of a parathyroid tumor in addition to other neoplasms.

Experience with extrarenal manifestations of hemorrhagic fever with renal syndrome in a tertiary care hospital in South Korea.

Reports on the clinical entity of hemorrhagic fever with renal syndrome (HFRS) have focused on acute renal failure. Data on the extrarenal manifestations are limited primarily to case reports. In this study, protean extrarenal manifestations involving the major organs occurred in one-third of patients with HFRS during various stages (i.e., febrile phase through diuretic phase). Pancreatobiliary manifestations and major bleeding occurred in 11% and 10% of patients, respectively. Cardiovascular and central nervous system manifestations developed during the febrile or oliguric phase, whereas pancreatobiliary manifestations and major bleeding were detected even in the diuretic phase. Thus, close monitoring of and additional knowledge about various extrarenal manifestations are needed.

Impact of renal dysfunction on clinical outcomes of acute coronary syndrome.

PURPOSE: The present study aimed to compare the clinical outcomes and to investigate prognostic factors of acute coronary syndrome (ACS) in patients with renal dysfunction (RD). MATERIALS AND METHODS: The study was a retrospective cohort of 648 adult patients admitted with ACS between October 2005 and December 2006. The estimated glomerular filtration rate (GFR) was classified into 4 levels: 1) normal, GFR greater than 90 mL/min/1.73 m(2); 2) mild RD, GFR of 60 to 90 mL/min/1.73 m(2); 3) moderate RD, GFR of 30 to 60 mL/min/1.73 m(2); and 4) severe RD, GFR less than 30 mL/min/1.73 m(2). Primary end points were death and complication in hospital courses. Secondary end points were major adverse cardiac event (MACE) during follow-up. RESULTS: The median follow-up was 505 +/- 183 days, the mean age was 63 +/- 12 years, and 71.8 percent of the group were men. A graded association was observed between severity of RD and clinical outcomes. Severe RD independently predicted MACE [hazard ratio, 2.731; 95% confidence interval (CI), 1.058 to 7.047, p = 0.038]. Low hemoglobin level was also an independent risk factor for MACE (hazard ratio, 1.155; 95% CI, 1.020 to 1.307, p = 0.022). Use of lipid-lowering therapy (hazard ratio, 0.456; 95% CI, 0.242 to 0.857, p = 0.015) was associated with reduced risk for MACE. CONCLUSION: Severe RD and low hemoglobin level were an independent risk factors for the mortality and complications of ACS, while lipid-lowering therapy was associated with reduced risk.