Dialysis patients who smoke are more hypertensive, more fluid overloaded and take more antihypertensive medications than nonsmokers.

Background: Smoking remains a powerful risk factor for death in end-stage renal disease (ESRD) and so is the presence of fluid overload. The relationship between smoking, blood pressure (BP) control and volume overload is insufficiently explored in patients on maintenance dialysis.Methods: This is a retrospective cross-sectional cohort study, utilizing existing patients' data generated during routine ESRD care, including bimonthly protocol bioimpedance fluid assessment of the volume status.Results: We analyzed the data of 63 prevalent patients receiving thrice weekly maintenance hemodiafiltration treatments at one rural dialysis unit in Hungary. The cohort's mean ± SD age was 61.5 ± 15.3 years; 65% male, 38% diabetic, with a mean arterial blood pressure (MAP) 99.5 ± 16.8 mmHg and Charlson score 3.79 ± 2.04. Of these, 38 patients were nonsmokers and 25 smokers. The nonsmokers' MAP was 94.3 ± 14.0 versus smokers' 105.9 ± 18.9 mmHg (p: .002); nonsmokers took an average 0.73 ± 0.92 antihypertensive medications vs. 1.73 ± 1.21 for smokers (p: .0001). The distribution of taking more antihypertensive medications is skewed toward a higher number among the smokers (2x5 chi square p: .004). By bioimpedance spectroscopy, nonsmokers had an average 10.93 ± 7.65 percent overhydration (OH) over the extracellular space compared to 17.63 ± 8.98 in smokers (p: .005).Conclusions: Smoking may be a significant mediator of not only BP but also of chronic fluid overload in ESRD patents. Additional, larger studies are needed to explore the mechanistic link between smoking and volume overload.

Uric Acid Control in Advanced Chronic Kidney Disease in a Southeastern US Urban Cohort.

OBJECTIVES: Uric acid (UA) control may be insufficient in chronic kidney disease (CKD) patients in the current era. It is unclear, however, whether this is the result of environmental effects, patient anthropometrics or insufficient dosing of medical therapy (allopurinol). METHODS: We have collected data on multiple clinical and laboratory parameters of 114 CKD clinic patients attending the nephrology clinic of the University of Mississippi Medical Center with an estimated glomerular filtration rate <45 mL · min-1 · 1.73 m2. We assessed the correlates of UA levels and the allopurinol doses along with achieved serum UA and urine pH. RESULTS: The cohort consisted of middle-aged to elderly patients with a mean (± standard deviation) age of 62.1 (11.6) years; 45.6% were female, 68.4% were African American and 47.4% had a history of gout. The mean UA level was 7.7 (2.49) mg/dL (range 3.1-16), allopurinol dose was 192 (99) mg/day (range 50-450) and estimated glomerular filtration rate was 23.8 (11.3) mL · min-1 · 1.73 m2. While the overall serum bicarbonate level was 25 (3.2) mEq/L, urine pH was <6 in 60.5% of the cohort. Significant univariate correlates of the administered doses of allopurinol were weight (r 0.317, P = 0.001), body mass index (BMI; r 0.313, P = 0.001), and female sex (r -0.198; P = 0.035). Achieved UA levels correlated directly with BMI (r 0.201, r = 0.036) but inversely with the allopurinol dose (r -0.196; P = 0.036). During logistic regression analysis with stepwise selection, only weight (ß 0.313, P = 0.001) and sex (ß -0.190, P = 0.039) proved to be predictive of the allopurinol dose; as for the achieved UA level, only BMI (ß 0.271, P = 0.006) and the allopurinol dose (ß -0.258; P = 0.009) had a significant effect. CONCLUSIONS: In patients with advanced CKD, conventional dosing recommendations for allopurinol are unlikely to suffice in reaching target serum UA goals. In our cohort, larger-than-usual allopurinol doses were well tolerated.

The effect of ambient temperature and humidity on interdialytic weight gains in end-stage renal disease patients on maintenance hemodialysis.

PURPOSE: Interdialytic weight gain (IDWG) is both a measure of dietary compliance and a well-established predictor of future adverse outcomes in dialysis patients. The impact of environmental conditions on IDWG in end-stage renal disease is little studied to date. METHODS: We retrospectively reviewed IDWG for 100 consenting chronic end-stage renal disease patients undergoing thrice weekly in-center hemodiafiltration under three different climatic conditions in a Central European city: Weekend_1 was humid (93 %) and warm (24 °C); Weekend_2 was dry (38 %) and hot (33 °C); and Weekend_3 was dry (30 %) and warm (24 °C). RESULTS: The cohort's mean age was 60.9 ± 14.7 years, all were Eastern European, and 56 % were men. Residual urine output measured 100 [25-75 % quartiles: 0, 612] mL/day, single-pool Kt/V 1.4 ± 0.25, and albumin 40.1 ± 3.9 g/L. Mean IDWGs measured as follows: Weekend_1 ("humid-warm"): 2973 ± 1386 mL; Weekend_2 ("dry-hot"): 2685 ± 1368 mL and Weekend_3 ("dry-warm"): 2926 ± 1311 mL. Paired-samples testing for difference showed higher fluid gains on the humid-warm (239 mL; 95 % CI 21-458 mL; p = 0.032) and on the dry-warm weekends (222 mL; 95 % CI -8 to 453 mL, p = 0.059), when compared to the dry-hot weekend. Under the latter, dry-hot climatic condition, residual urine output lost its significance to impact IDWG during multiple regression analysis. CONCLUSION: While excess temperature may impact IDWG to a small degree, air humidity does not; the least weight gains occurred on the dry-hot weekend. However, the effects of both were minimal under continental summer conditions and are unlikely to explain large excesses of individual session-to-session variations.

Tunneled Hemodialysis Catheter Removals by Non-Interventional Nephrologists: The University of Mississippi Experience.

Bedside removal of tunneled hemodialysis catheters (TDC) by noninterventional Nephrologists has not been frequently performed or studied. We performed a retrospective review of bedside TDC removal at the University of Mississippi Medical Center between January, 2010 and June, 2013. We collected data on multiple patients and procedure-related variables, success, and complications rates. Of the 138 subjects, mean age was 50 (±15.9) years, 49.3% were female, 88.2% African American and 41% diabetics. Site of removal was the right internal jugular (IJ) in 76.8%, the left IJ in 15.2%, and the femoral vein in 8% of patients. Exactly 44.9% of removals took place in the outpatient setting. Main indications for the removal were proven bacteremia in 30.4%, sepsis or clinical concerns for infection in 15.2% of the cases, while TDC was no longer necessary in 52.2% of patients. All removals were technically successful and well tolerated, but we observed Dacron "cuff" separation and subcutaneous retention in 6.5% of the cases. There was a significant association between outpatient removal and cuff retention (p = 0.007), but not with the site of removal or operator experience. In this relatively large mixed cohort of inpatients and outpatients, bedside TDC removal was well tolerated with a minimal complication rate.

Diuretics and bioimpedance-measured fluid spaces in hypertensive patients.

The authors examined the relationship between thiazide-type diuretics and fluid spaces in a cohort of hypertensive patients in a retrospective study of 60 stable hypertensive patients without renal abnormalities who underwent whole-body bioimpedance analysis. Overhydration was greater in the diuretic group, but only to a nonsignificant degree (5.9 vs. 2.9%; P=.21). The total body water did not differ in the two groups (41.8 L vs. 40.5 L; P=.64). Extracellular fluid volume (ECV) (19.7 L vs. 18.5 L; P=.35) and intracellular fluid volume (ICV) spaces (20.8 L vs. 21.3 L; P=.75) were also not significantly different in the two groups. The ratio of ICV:ECV, however, appeared different: 1.05 vs 1.15 (P=.017) and the effect was maintained in the linear regression-adjusted model (ß coefficient: -0.143; P=.001). The diuretic-related distortion of ICV:ECV ratio indicates potential fluid redistribution in hypertensive patients, with ICV participating in the process.

Volume estimation in dialysis patients: the concordance of brain-type natriuretic peptide measurements and bioimpedance values.

Correct estimation of the dialysis patients' hydration status remains an important clinical challenge. Bioimpedance measurements have been validated by various physiological tests, and the use of brain-type natriuretic peptide (BNP) has been validated by inferior vena cava diameter measurements. This is an observational cohort study that evaluated the correspondence between bioimpedance-measured overhydration percentage (OH%) and BNP. We measured predialysis OH% by bioimpedance apparatus (Body Composition Monitor) and BNP by microparticle enzyme-linked immunoassay in 41 prevalent stable hemodialysis patients, 19 (46%) women, aged 58.9 ± 14.5 years. The cohort's average BNP was 2694 ± 3278 pg/mL and 10 (24.4%) of these 41 patients had BNP < 500 pg/mL (average 260.7 ± 108.5). The OH% was 8.5 ± 7.0% among those with a BNP < 500 pg/mL, while the rest of the population had an OH% of 21.4 ± 8.0%, corresponding to excess volumes of 1.6 ± 1.3 and 4.4 ± 3.8 L, respectively. The OH% vs. BNP relationship was best described by the exponential regression of y = 216.4e(0.097x) , predicting a BNP of 216.4 pg/mL at 0% overhydration status (r 0.61). Receiver-operating curves revealed an area under the curve of 0.885 for BNP when the OH% was set ≥15% of overhydration and an area under the curve of 0.918 for OH% when the BNP was set ≥500 pg/mL for being abnormal. We conclude that in our cohort there was a high degree of correspondence between these two tests with an exponential relationship between the measurements.

Ambulatory blood pressure monitoring and peri-hemodialysis blood pressures in a southeast US hemodialysis unit.

AIMS: End-stage renal disease (ESRD) patients on dialysis are perceived to have difficult-to-control blood pressure (BP) and commonly treated with complex antihypertensive regimens. Our hypothesis was that peri-dialysis BP will overestimate the true burden of hypertension in these patients. SUBJECTS AND METHODS: We performed 44-h ambulatory blood pressure monitoring (ABPM) in 43 patients recruited from the University of Mississippi outpatient dialysis unit. Data collected included routine peri-dialysis blood systolic blood pressure (SBP), diastolic blood pressure (DBP), weight gain, and demographic information. We investigated whether the pre-dialysis or post-dialysis blood pressure would better correspond to the ABPM results. RESULTS: The mean age of participants was 50.5 ± 12.05 years, 95% African-American, and 44% diabetic with an average dialysis vintage of 31.1 ± 30 months. The mean SBP and DBP were 164.6/87.9 mmHg ± 22.3/15 before dialysis, 151.5/81.3 mmHg ± 24.1/13 after dialysis and 136/80.6 mmHg ± 23.5/14.7 during ABPM. There were wide limits of agreements between peri-dialysis BP and ABPM, the largest with pre-dialysis SBP (28.5 ± 16.6 mmHg) and the least with post-dialysis DBP (0.7 ± 10 mmHg). With both peri-dialysis BP measurements as explanatory variables in a linear regression model, only the post-dialysis SBP (ß 0.716; p < 0.001) but not pre-dialysis SBP (ß 0.157; p = 0.276) had a significant independent association with ABPM systolic BP. For DBP, both pre-dialysis (ß 0.543; p = 0.001) and post-dialysis (ß 0.317; p = 0.037) values retained correlation with DBP on ABPM. CONCLUSION: Peri-dialysis measurements overestimated true BP burden in this Southeastern U.S. cohort of ESRD patients. When BP readings from outside the dialysis unit are notavailable, assessment of BP control should focus pre-dialysis on DBP and post-dialysison both SBP and DBP.

Dialysis patients' fluid overload, antihypertensive medications, and obesity.

Overhydration (OH) is both a major etiology of hypertension in hemodialysis patients and a serious risk factor for mortality. We investigated the association of multiple variables and OH. This is a cross-sectional study of prevalent hemodialysis patients examining the predialysis hydrational status with a portable bioimpedance apparatus to measure the degree of hydration. We completed our study in 79 patients. Patients were overhydrated by 2.6 ± 2.4 L. The mean medication count was 2.4 ± 1.5, and 50.7% had diuretics. We found a significant correlation between OH and systolic blood pressure (r = 0.39; p = 0.0006), each liter of OH generating 3.6 mm Hg. We also found a positive correlation between the use of diuretics and OH (p = 0.003, two-tailed Student's t test) but no correlation between OH and body weight (r < 0.0001; p = 0.99), body mass index (r = -0.17), age (r = 0.089), and vintage (r = 0.05). For every 10% increase in body fat, OH decreased by 1.2 L; residual urine output gave no protection from OH (r = 0.077) and did not correlate with blood pressure (r = 0.01). Overhydration is strongly associated with the use of antihypertensive medications and the use of diuretics in this dialysis population. Obesity seems to afford some protection from OH.

High prevalence of liddle syndrome phenotype among hypertensive US Veterans in Northwest Louisiana.

Liddle syndrome (LS) is an autosomal dominant disorder due to a gain-of-function mutation in the epithelial Na(+) channel and is perceived to be a rare condition. A cross-sectional study of 149 hypertensive patients with hypokalemia (<4 mmol/dL) or elevated serum bicarbonate (>25 mmol/dL) was conducted at a Veterans' Administration Medical Center Hypertension Clinic in Shreveport, LA. Data on demographics, blood pressure, and select blood tests were collected and expressed as percentages for categoric variables and as mean ± standard deviation (SD) for continuous variables. Patients were diagnosed with likely LS when the plasma renin activity (PRA) was <0.35 µU/mL/h and the aldosterone was <15 ng/dL and likely primary hyperaldosteronism (PHA) with PRA <0.35 µU/mL/h and aldosterone level >15 ng/dL. The cohort included predominantly elderly (67.1±13.4 years), male (96%), and Caucasian (57%) patients. The average blood pressure was 143.8/79.8 mm Hg±27.11/15.20 with 3.03±1.63 antihypertensive drugs. Based on the above criteria, 9 patients (6%) satisfied the criteria for likely LS and 10 patients (6.7%) were diagnosed with likely PHA. In this hypothesis-generating study, the authors detected an unusually high prevalence of biochemical abnormalities compatible with likely LS syndrome from Northwestern Louisiana, approaching that of likely PHA.

Volume-related weight gain and subsequent mortality in acute renal failure patients treated with continuous renal replacement therapy.

Fluid overload is a frequent finding in critically ill patients suffering from acute kidney injury (AKI). To assess the impact of fluid overload on the mortality of AKI patients treated with continuous renal replacement therapy (CRRT), we used a registry of 81 critically ill patients with AKI initiated on CRRT assembled over an 18-month period to conduct a cross- sectional analysis using volume-related weight gain (VRWG) of > or =10% and > or =20% of body weight and oliguria (< or =20 ml/h) as the principal variables, with the primary outcome measure being mortality at 30 days. Mean Apache II scores were 27.5 +/- 6.9 with overall cohort mortality of 50.6%. Mean (+/-SD) VRWG was 8.3 +/- 9.6 kg, representing a 10.2% +/- 13.5% increase since admission. Oliguria was present in 65.4% of patients. Odds ratio (OR) for mortality on univariate analysis was increased to 2.62 [95% confidence interval (CI): 1.07-6.44] by a VRWG > or =10% and to 3.22 (95% CI: 1.23-8.45) by oliguria. VRWG > or =20% had OR of 3.98 (95% CI: 1.01-15.75; p = 0.049) for mortality. Both VRWG > or =10% (OR 2.71, p = 0.040) and oliguria (OR 3.04, p = 0.032) maintained their statistically significant association with mortality in multivariate models that included sepsis and Apache II score. In conclusion, fluid overload is an important prognostic factor for survival in critically ill AKI patients treated with CRRT. Further studies are needed to elicit mechanisms and develop appropriate interventions.

Regional differences in nonadherence to dialysis among southern dialysis patients: a comparative cross-sectional study to the dialysis outcomes and practice patterns study.

INTRODUCTION: Treatment outcomes of end-stage renal disease (ESRD) vary significantly between European, Japanese, and American populations. The Dialysis Outcomes and Practice Patterns Study (DOPPS) described multiple differences between these cohorts; however, remarkable outcome differences exist among regions within the American population. Southern networks continue to have higher degrees of adverse outcomes despite improvements in healthcare delivery. METHODS: We examined the demographic indices and the degree of nonadherence to dialysis prescription among a sample of 97 patients with ESRD from the Northwestern Louisiana, Southern Arkansas and Northeast Texas area through face-to-face interviews and chart review and compared them with the published DOPPS results. RESULTS: We found a significant difference between this Southern ESRD population and the overall American DOPPS cohort in demographics and dialysis adherence. Most (95.8%) patients were of African American ancestry and had a longer vintage on dialysis. Most patients were nonadherent as assessed by 2 of 4 measures of dialysis adherence: 29.2% of patients did not attend at least 1 dialysis session per month, and 86.4% shortened their dialysis session by 10 minutes or more at least 1 per month. These parameters were identified as major risk factors for adverse outcome in the DOPPS study. CONCLUSION: This Southern patient cohort is different from the rest of the American ESRD population in terms of important measures of dialysis adherence. Such differences might contribute to our understanding of regional disparity in outcomes.

Localization of human herpesvirus type 8 in human sperms by in situ PCR.

OBJECTIVES: Defining the mechanism of infection with human herpesvirus-8 (HHV-8) or Kaposi's sarcoma associated herpesvirus (KSHV) is an important clinical issue. HHV-8 has been linked to Kaposi's sarcoma (KS) development in HIV-1-infected individuals, and KS develops in 40% of those infected with both viruses. A series of epidemiological data suggest that sexual transmission is one of the routes of transmission for HHV-8. In our studies, we sought to assess the cellular reservoirs of HHV-8 DNA in the semen of HIV-1-infected men and the potential role of HHV-8 infected spermatozoa in horizontal transmission. DESIGN AND METHODS: A nested polymerase chain reaction (PCR), in situ PCR (ISPCR) and a sodium iodide (NaI) DNA isolation technique that extracts both nuclear and episomal DNA were utilized to amplify specific genes in vitro and within intact cells to evaluate the types of seminal cells infected with HHV-8 in HIV-1-infected and uninfected men. RESULTS: HHV-8 was present in the spermatozoa and mononuclear cells of the semen in 64 of 73 (88%) HIV-1 infected individuals. Both the sperms as well as the mononuclear cells of the semen specimens of HIV-1 infected men were found to be infected with HHV-8. Multiplex ISPCR revealed that a significantly higher percentage of semen cells were infected with HHV-8 than HIV-1 (p>0.001). Rare (less than one in a 100,000) sperm cells were co-infected with both viruses. A co-culture of HHV-8 infected sperm with uninfected 293 or Sup-T1 cell lines resulted in an abortive infection of these cells with HHV-8. DNA isolation by NaI yielded 73% of the positive sperm, whereas the standard phenol/chloroform method resulted in significantly lower positives (45%) from the same specimens. CONCLUSIONS: Design and methods: Our data strongly suggest a potential sexual/horizontal route of transmission of HHV-8, via the HHV-8 infected sperm and other semen cells, where a large percentage of HIV-1 infected men's sperm and other semen cells are infected with HHV-8. Co-culture studies have further supported the observations that HHV-8 in the sperm cells is infectious and capable of transmission of the virus to uninfected cells.