Search PubMed⌕ Search

Biomedical subjects

F K Port

Publications and source records attributed to F K Port.

At least 19 recordsLinked to original sources
PubMed2006

Longer treatment time and slower ultrafiltration in hemodialysis: associations with reduced mortality in the DOPPS.

Longer treatment time (TT) and slower ultrafiltration rate (UFR) are considered advantageous for hemodialysis (HD) patients. The study included 22,000 HD patients from seven countries in the Dialysis Outcomes and Practice Patterns Study (DOPPS). Logistic regression was used to study predictors of TT > 240 min and UFR > 10 ml/h/kg bodyweight. Cox regression was used for survival analyses. Statistical adjustments were made for patient demographics, comorbidities, dose of dialysis (Kt/V), and body size. Europe and Japan had significantly longer (P < 0.0001) average TT than the US (232 and 244 min vs 211 in DOPPS I; 235 and 240 min vs 221 in DOPPS II). Kt/V increased concomitantly with TT in all three regions with the largest absolute difference observed in Japan. TT > 240 min was independently associated with significantly lower relative risk (RR) of mortality (RR = 0.81; P = 0.0005). Every 30 min longer on HD was associated with a 7% lower RR of mortality (RR = 0.93; P < 0.0001). The RR reduction with longer TT was greatest in Japan. A synergistic interaction occurred between Kt/V and TT (P = 0.007) toward mortality reduction. UFR > 10 ml/h/kg was associated with higher odds of intradialytic hypotension (odds ratio = 1.30; P = 0.045) and a higher risk of mortality (RR = 1.09; P = 0.02). Longer TT and higher Kt/V were independently as well as synergistically associated with lower mortality. Rapid UFR during HD was also associated with higher mortality risk. These results warrant a randomized clinical trial of longer dialysis sessions in thrice-weekly HD.

Adult↗
PubMed2006

Mortality risk for patients receiving hemodiafiltration versus hemodialysis: European results from the DOPPS.

Hemodiafiltration (HDF) is used sporadically for renal replacement therapy in Europe but not in the US. Characteristics and outcomes were compared for patients receiving HDF versus hemodialysis (HD) in five European countries in the Dialysis Outcomes and Practice Patterns Study. The study followed 2165 patients from 1998 to 2001, stratified into four groups: low- and high-flux HD, and low- and high-efficiency HDF. Patient characteristics including age, sex, 14 comorbid conditions, and time on dialysis were compared between each group using multivariate logistic regression. Cox proportional hazards regression assessed adjusted differences in mortality risk. Prevalence of HDF ranged from 1.8% in Spain to 20.1% in Italy. Compared to low-flux HD, patients receiving low-efficiency HDF had significantly longer average duration of end-stage renal disease (7.0 versus 4.7 years), more history of cancer (15.4 versus 8.7%), and lower phosphorus (5.3 versus 5.6 mg/dl); patients receiving high-efficiency HDF had significantly more lung disease (15.5 versus 10.2%) and received a higher single-pool Kt/V (1.44 versus 1.35). High-efficiency HDF patients had lower crude mortality rates than low-flux HD patients. After adjustment, high-efficiency HDF patients had a significant 35% lower mortality risk than those receiving low-flux HD (relative risk=0.65, P=0.01). These observational results suggest that HDF may improve patient survival independently of its higher dialysis dose. Owing to possible selection bias, the potential benefits of HDF must be tested by controlled clinical trials before recommendations can be made for clinical practice.

Europe↗
PubMed2006

Mortality after kidney transplantation: a comparison between the United States and Canada.

There is a paucity of comparative studies on country-specific outcomes in kidney transplantation. We compared post-transplant mortality among primary, adult, solitary kidney transplant recipients (KTR) from the United States (n = 70 708) and Canada (n = 5773), between January 1, 1991 and December 31, 1998, using data from the Scientific Registry of Transplant Recipients and the Canadian Organ Replacement Register. Multivariable Cox regression revealed higher adjusted post-transplant mortality among U.S. (vs. Canadian) KTR (HR = 1.35 [95% CI 1.24, 1.47; p < 0.005]). Mortality risk in the first post-transplant year was similar in both countries but higher in the United States beyond the first year (HR = 1.49-1.53; p < 0.005). There was no difference in mortality among patients transplanted within 1 year of starting dialysis, but mortality was increased in U.S. (vs. Canadian) patients after 1-2 and 4+ years on dialysis (HR = 1.36-1.66; p < 0.005). Greater mortality was also seen in U.S. patients with diabetes mellitus and/or graft failure. In conclusion, there are considerable differences in the survival of KTR in the United States and Canada. A detailed examination of factors contributing to this variation may yield important insights into improving outcomes for all KTR.

Adolescent↗
PubMed2006

Report of a National Conference on Donation after cardiac death.

A national conference on organ donation after cardiac death (DCD) was convened to expand the practice of DCD in the continuum of quality end-of-life care. This national conference affirmed the ethical propriety of DCD as not violating the dead donor rule. Further, by new developments not previously reported, the conference resolved controversy regarding the period of circulatory cessation that determines death and allows administration of pre-recovery pharmacologic agents, it established conditions of DCD eligibility, it presented current data regarding the successful transplantation of organs from DCD, it proposed a new framework of data reporting regarding ischemic events, it made specific recommendations to agencies and organizations to remove barriers to DCD, it brought guidance regarding organ allocation and the process of informed consent and it set an action plan to address media issues. When a consensual decision is made to withdraw life support by the attending physician and patient or by the attending physician and a family member or surrogate (particularly in an intensive care unit), a routine opportunity for DCD should be available to honor the deceased donor's wishes in every donor service area (DSA) of the United States.

Adolescent↗
PubMed2006

Geographic differences in event rates by model for end-stage liver disease score.

The ability of the model for end-stage liver disease (MELD) score to accurately predict death among liver transplant candidates allows for evaluation of geographic differences in transplant access for patients with similar death risk. Adjusted models of time to transplant and death for adult liver transplant candidates listed between 2002 and 2003 were developed to test for differences in MELD score among Organ Procurement and Transplantation Network (OPTN) regions and Donation Service Areas (DSA). The average MELD and relative risk (RR) of death varied somewhat by region (from 0.82 to 1.28), with only two regions having significant differences in RRs. Greater variability existed in adjusted transplant rates by region; 7 of 11 regions differed significantly from the national average. Simulation results indicate that an allocation system providing regional priority to candidates at MELD scores > or = 15 would increase the median MELD score at transplant and reduce the total number of deaths across DSA quintiles. Simulation results also indicate that increasing priority to higher MELD candidates would reduce the percentage variation among DSAs of transplants to patients with MELD scores > or = 15. The variation decrease was due to increasing the MELD score at time of transplantation in the DSAs with the lowest MELD scores at transplant.

Adult↗
PubMed2005

Estimating the impact of renal replacement therapy choice on outcome in severe acute renal failure.

BACKGROUND: Mortality in severe acute renal failure (ARF) requiring renal replacement therapy (RRT) approximates 50% and varies with clinical severity. Continuous RRT (CRRT) has theoretical advantages over intermittent hemodialysis (IHD) for critical patients, but a survival advantage with CRRT is yet to be clearly demonstrated. To date, no prospective controlled trial has sufficiently answered this question, and the present prospective outcome study attempts to compare survival with CRRT versus that with IHD. METHODS: Multivariable Cox-proportional hazards regression was used to analyze the impact of RRT modality choice (CRRT vs. IHD) on in-hospital and 100-day mortality among ARF patients receiving RRT during 2000 and 2001 at University of Michigan, using an "intent-to-treat" analysis adjusted for multiple comorbidity and severity factors. RESULTS: Overall in-hospital mortality before adjustment was 52%. Triage to CRRT (vs IHD) was associated with higher severity and unadjusted relative rate (RR) of in-hospital death (RR = 1.62, p = 0.001, n = 383). Adjustment for comorbidity and severity of illness reduced the RR of death for patients triaged to CRRT and suggested a possible survival advantage (RR = 0.81, p = 0.32). Analysis restricted to patients in intensive care for more than five days who received at least 48 hours of total RRT, showed the RR of in-hospital mortality with CRRT to be nearly 45% lower than IHD (RR = 0.56, n = 222), a difference in RR that indicates a strong trend for in-hospital mortality with borderline statistical significance (p = 0.069). Analysis of 100-day mortality also suggested a potential survival advantage for CRRT in all cohorts, particularly among patients in intensive care for more than five days who received at least 48 h of RRT (RR = 0.60, p = 0.062, n = 222). CONCLUSION: Applying the present methodology to outcomes at a single tertiary medical center, CRRT may appear to afford a survival advantage for patients with severe ARF treated in the ICU. Unless and until a prospective controlled trial is realized, the present data suggest potential survival advantages of CRRT and support broader application of CRRT among such critically ill patients.

APACHE↗
PubMed2002

Cardiovascular mortality in children and young adults with end-stage kidney disease.

OBJECTIVE: To analyze cardiovascular death in a national end-stage renal disease (ESRD) population. STUDY DESIGN: This retrospective, observational study with data from the US Renal Data Systems analyzed 1380 deaths from 1990 to 1996 among patients who started ESRD therapy as children and died before 30 years of age. RESULTS: Percentage of cardiac deaths (n = 311) varied by age and was higher among black patients (0-4 years, 36%; 5-9 years, 18%; 10-14 years, 35%; 15-19 years, 22%; 20-30 years, 32%) than white patients (18%, 12%, 17%, 14%, and 23%, respectively). Among black patients, cardiac deaths occurred in 11% of transplant recipients, 34% of dialysis patients, and among white patients 9% and 25%, respectively. Black patients were 1.6 times more likely to die of a cardiac death (P <.001) than white patients. Transplant recipients had 78% lower risk of cardiac death than dialysis patients (odds ratio = 0.22; P =.0001). The cardiac death rate among dialysis patients was 21.4 per 1000 patient-years in black patients compared with 20.5 in white patients. Transplantation cardiac death rates were lower in black patients, 2.1 per 1000 patient-years, and 1.3 in white patients. CONCLUSIONS: Cardiovascular death accounts for 23% of pediatric and young adult ESRD deaths. Black patients and dialysis patients are at higher risk of a cardiac death compared with white patients and transplant recipients. Further studies are needed to identify risk factors associated with cardiovascular death in patients with ESRD.

Adolescent↗
PubMed2002

Race and glomerulonephritis in patients with and without hepatosplenic Schistosomiasis mansoni.

BACKGROUND/AIMS: United States investigators have shown evidence of higher susceptibility to focal segmental glomerulosclerosis (FSGS) in blacks than in whites. This association between race and FSGS has not been assessed outside the US. The present study assesses the association between race and type of glomerulonephritis in a sample of Brazilian patients, taking into account the presence of the hepatosplenic form of Schistosomiasis mansoni (HSM). METHODS: Eighty patients with focal segmental glomerulosclerosis (FSGS) were compared to 50 with membranoproliferative glomerulonephritis (MPGN). The association between race (i.e. black versus white) and type of glomerulonephritis was adjusted for age, gender and HSM by logistic regression. RESULTS: Blacks were more likely than whites to have FSGS (as compared to MPGN), both among patients with HSM (odds ratio (OR) = 2.67; 95% confidence interval (CI) = 0.81 - 8.81) and without HSM (OR = 2.19; 95% CI = 0.79 - 6.05). After adjustment for age, gender and HSM, the odds of FSGS remained significantly greater for blacks (OR = 2.49; 95% CI = 1.05 - 5.95). CONCLUSION: The increased likelihood of FSGS in Brazilian blacks is consistent with findings from US patients. The association between race and type of glomerulonephritis was similar between patients with and without HSM. Future investigations should focus on the mediators factors that might explain these findings.

Adolescent↗
PubMed2001

The impact of simultaneous pancreas-kidney transplantation on long-term patient survival.

BACKGROUND: Simultaneous pancreas-kidney transplantation (SPK) ameliorates the progression of microvascular diabetic complications but the procedure is associated with excess initial morbidity and an uncertain effect on patient survival when compared with solitary cadaveric or living donor renal transplantation. We evaluated mortality risks associated with SPK, solitary renal transplantation, and dialysis treatment in a national cohort of type 1 diabetics with end-stage nephropathy. METHODS: A total of 13,467 adult-type 1 diabetics enrolled on the renal and renal-pancreas transplant waiting list between 10/01/88 and 06/30/97 were followed until 06/30/98. Time-dependent mortality risks and life expectancy were calculated according to the treatment received subsequent to wait-list registration: SPK; cadaveric kidney only (CAD); living donor kidney only (LKD) transplantation; and dialysis [wait-listed, maintenance dialysis treatment (WLD)]. RESULTS: Adjusted 10-year patient survival was 67% for SPK vs. 65% for LKD recipients (P=0.19) and 46% for CAD recipients (P<0.001). The excess initial mortality normally associated with renal transplantation and the risk of early infectious death was 2-fold higher in SPK recipients. The time to achieve equal proportion of survivors as the WLD patients was 170, 95, and 72 days for SPK, CAD, and LKD recipients, respectively (P<0.001). However, the adjusted 5-year morality risk (RR) using WLD as the reference and the expected remaining life years were 0.40, 0.45, and 0.75 and 23.4, 20.9, and 12.6 years for SPK, LKD, and CAD, respectively. There was no survival benefit in SPK recipients > or =50 years old (RR=1.38, P=0.81). CONCLUSIONS: Among patients with type 1 DM with end-stage nephropathy, SPK transplantation before the age of 50 years was associated with long-term improvement in survival compared to solitary cadaveric renal transplantation or dialysis.

Adult↗
PubMed2001

Type of vascular access and mortality in U.S. hemodialysis patients.

BACKGROUND: Vascular access (VA) complications account for 16 to 25% of hospital admissions. This study tested the hypothesis that the type of VA in use is correlated with overall mortality and cause-specific mortality. METHODS: Data were analyzed from the U.S. Renal Data System Dialysis Morbidity and Mortality Study Wave 1, a random sample of 5507 patients, prevalent on hemodialysis as of December 31, 1993. The relative mortality risk during a two-year observation was analyzed by Cox-regression methods with adjustments for demographic and comorbid conditions. Using similar methods, cause-specific analyses also were performed for death caused by infection and cardiac causes. RESULTS: In diabetic mellitus (DM) patients with end-stage renal disease, the associated relative mortality risk was higher for those with arteriovenous graft (AVG; RR = 1.41, P < 0.003) and central venous catheter (CVC; RR = 1.54, P < 0.002) as compared with arteriovenous fistula (AVF). In non-DM patients, those with CVC had a higher associated mortality (RR = 1.70, P < 0.001), as did to a lesser degree those with AVG (RR = 1.08, P = 0.35) when compared with AVF. Cause-specific analyses found higher infection-related deaths for CVC (RR = 2.30, P < 0.06) and AVG (RR = 2.47, P < 0.02) compared with AVF in DM; in non-DM, risk was higher also for CVC (RR = 1.83, P < 0.04) and AVG (RR = 1.27, P < 0.33). In contrast to our hypothesis that AV shunting increases cardiac risk, deaths caused by cardiac causes were higher in CVC than AVF for both DM (RR = 1.47, P < 0.05) and non-DM (RR = 1.34, P < 0.05) patients. CONCLUSION: This case-mix adjusted analysis suggests that CVC and AVG are correlated with increased mortality risk when compared with AVF, both overall and by major causes of death.

Arteriovenous Shunt, Surgical↗
PubMed2001

Mortality risk by hemodialyzer reuse practice and dialyzer membrane characteristics: results from the usrds dialysis morbidity and mortality study.

Hemodialyzer reuse is commonly practiced in the United States. Recent studies have raised concerns about the mortality risk associated with certain reuse practices. We evaluated adjusted mortality risk during 1- to 2-year follow-up in a representative sample of 12,791 chronic hemodialysis patients treated in 1,394 dialysis facilities from 1994 through 1995. Medical record abstraction provided data on reuse practice, use of bleach, dialyzer membrane, dialysis dose, and patient characteristics and comorbidity. Mortality risk was analyzed by bootstrapped Cox models by (1) no reuse versus reuse, (2) reuse agent, and (3) dialyzer membrane with and without the use of bleach, while considering dialysis and patient factors. The relative risk (RR) for mortality did not differ for patients in reuse versus no-reuse units (RR = 0.96; 95% confidence interval [CI], 0.86 to 1.08; P > 0.50), and similar results were found with different levels of adjustment and subgroups (RR = 1.01 to 1.05; 95% CI, lower bound > 0.90, upper bound < 1.19 each; each P > 0.40). The RR for peracetic acid mixture versus formalin varied significantly by membrane type and use of bleach during reprocessing, achieving borderline significance for synthetic membranes. Among synthetic membranes, mortality was greater with low-flux than high-flux membranes (RR = 1.24; 95% CI, 1.02 to 1.52; P = 0.04) and without than with bleach during reprocessing (RR = 1.24; 95% CI, 1.01 to 1.48; P = 0.04). Among all membranes, mortality was lowest for patients treated with high-flux synthetic membranes (RR = 0.82; 95% CI, 0.72 to 0.93; P = 0.002). Although mortality was not greater in reuse than no-reuse units overall, differences may exist in mortality risk by reuse agent. Use of high-flux synthetic membrane dialyzers was associated with lower mortality risk, particularly when exposed to bleach. Clearance of larger molecules may have a role.

Ambulatory Care Facilities↗
PubMed2001

Incidence trends and mortality in end-stage renal disease attributed to renovascular disease in the United States.

End-stage renal disease (ESRD) attributed to renovascular disease (RVD-ESRD) has been incompletely characterized. We determined incidence trends, clinical features, prior treatment, and survival of patients with RVD-ESRD using the US Renal Data System database. Primary causes of ESRD were assessed in patients starting ESRD therapy during 1991 to 1997. The incidence of RVD-ESRD increased from 2.9/10(6) per year (1.4% of new ESRD cases) to 6.1/10(6) per year (2.1%). The annualized increase was 12.4% per year. This is a greater rate of increase than for ESRD from diabetes mellitis (DM-ESRD; 8.3% per year) and ESRD overall (5.4% per year). The risk for RVD-ESRD versus other-cause ESRD correlated positively with age (odds ratio [OR], 1.7 per 10-year increment; P < 0.0001) and male sex (OR, 1.2; P < 0.0001) and negatively with black (OR, 0.17; P < 0.0001), Asian (OR, 0.29; P < 0.0001), and Native American race (OR, 0.31; P < 0.0001). The unadjusted prevalence of coronary heart disease, cerebrovascular disease, and peripheral vascular disease was greater in patients with RVD-ESRD versus other-cause ESRD (P < 0.001). Of patients with RVD-ESRD, 5% underwent revascularization in the 2 years before ESRD compared with 0.5% of patients with other-cause ESRD, including DM-ESRD. Adjusted for age, race, sex, comorbidity, and laboratory values, the survival of patients with RVD-ESRD was similar to that for patients with other-cause ESRD (risk ratio, 1.01; P = 0.5). These findings suggest that RVD-ESRD is increasing faster than other-cause ESRD and is not independently associated with an increased mortality risk. Strategies may exist to prevent progression to ESRD and merit priority for further study.

Adult↗
PubMed2001

Use of ACE inhibitors is associated with prolonged survival of arteriovenous grafts.

Vascular access complications are common in hemodialysis patients. To investigate whether the use of angiotensin-converting enzyme (ACE) inhibitors influences the rate of polytetrafluoroethylene (PTFE) graft complications, we compared the rate of intervention-free graft survival among patients treated versus not treated with ACE inhibitors. We retrospectively analyzed the survival of grafts placed at our institution between January 1, 1995, and October 31, 1999. Among 121 grafts, 25 grafts were placed in 19 patients treated with ACE inhibitors and 96 grafts were placed in 68 patients not treated with ACE inhibitors. Follow-up ranged from 1 month to 5 years. Ten of 25 grafts failed in the ACE-inhibitor group and 62 of 95 grafts failed in the non-ACE-inhibitor group. Actuarial intervention-free access survival rates (Kaplan-Meier) were significantly greater in the ACE-inhibitor than non-ACE-inhibitor group (71% versus 53% at 6 months, 58% versus 35% at 12 months, and 44% versus 22% at 24 months; P = 0.04). Using a Cox model adjusting for age, race, sex, and diabetes, the relative risk (RR) for access failure in the ACE-inhibitor group was 53% less than in the non-ACE-inhibitor group (RR, 0.47; p < 0.03). In a more complex Cox model with additional adjustment for comorbid conditions, the RR was even lower (RR, 0.32; P = 0.003) for the ACE-inhibitor compared with non-ACE-inhibitor group (reference = 1.00). The lower RR was observed for patients with and without congestive heart failure. These results suggest that ACE inhibitors offer clinical promise in the prevention of PTFE graft failure. A prospective randomized trial is warranted to confirm the benefit of ACE inhibitors.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2001

Body mass index and mortality in 'healthier' as compared with 'sicker' haemodialysis patients: results from the Dialysis Outcomes and Practice Patterns Study (DOPPS).

BACKGROUND: Haemodialysis (HD) patients with lower body mass index (BMI) have a higher relative mortality risk (RR), irrespective of race. However, only Asian Americans treated with HD have been found to have an elevated RR with higher BMI. Asian Americans on HD are 'healthier' than other race groups (i.e. have better overall survival). We hypothesized that an increased mortality risk might be associated with high BMI in a variety of other 'healthier' subgroups of HD patients. METHODS: The prospective Dialysis Outcomes and Practice Patterns Study (DOPPS) provided baseline demographic, comorbidity and BMI data on 9714 HD patients in the US and Europe (France, Germany, Italy, Spain, and the UK) from 1996-2000. Using multivariate survival analyses, we evaluated BMI-mortality relationships in HD subpopulations defined by continent, race (black and white), gender, tertiles of severity of illness (based on a score derived from comorbid conditions and serum albumin concentration), age (<45, 45-64, >or=65), smoking, and diabetic status. RESULTS: Relative mortality risk decreased with increasing BMI. This was statistically significant (P<0.007) except for the smallest subgroup of patients who were <45 years old and were also in the healthiest tertile of comorbidity. All else equal, BMI <20 was consistently associated with the highest relative mortality risk. Overall a lower relative mortality risk (RR) as compared with BMI 23-24.9, was found for overweight (BMI 25-29.9; RR 0.84, P=0.008), for mild obesity (BMI 30-34.9; RR 0.73, P=0.0003), and for moderate obesity (BMI 35-39.9; RR 0.76, P=0.02). CONCLUSION: In a wide variety of HD patient subgroups, differing with respect to their baseline health status, increasing body size correlates with a decreased mortality risk. This contrasts with the association between BMI and mortality in the general population, and deserves further study.

Adult↗
PubMed2001

[Dialysis Outcomes and Practice Patterns Study: data on the use of central venous catheters in chronic hemodialysis].

Central venous catheters are widely used as vascular accesses for chronic haemodialysis. Different factors may lead to catheter use, whether clinical such as emergency dialysis, or related to practices specific to each dialysis unit or country. The Dialysis Outcomes and Practice Patterns Study is an observational study of more than 10,000 representative patients treated by haemodialysis followed over a two-year period in the United States, Japan, and in five European countries (France, Germany, Italy, Spain, United Kingdom). DOPPS data from the United States and Europe about catheters are reported in this paper. Catheter use is less frequent in Europe than in the US, both in incident and prevalent patients, and in patients who have been seen by a nephrologist in the pre-dialysis period. Tunneled and untunneled catheters are each associated with a significantly higher frequency of access infection compared to native arteriovenous fistulae and grafts. Patients with important comorbidities such as diabetes, cardiovascular diseases, malnutrition or dementia are more likely to be dialysed with tunneled catheters. Furthermore, patients initiating hemodialysis with a tunneled catheter display higher mortality risk compared to patients starting hemodialysis with a permanent access. In summary, DOPPS data indicate that central venous catheters are used for chronic haemodialysis in patients with a high level of morbidity, and that their utilisation is associated to an additional risk, particularly of infection, and to a lower survival for tunneled catheters. Appropriate care should limit the utilisation of central venous catheters to clinically undisputable indications.

Catheterization, Central Venous↗