Biomedical subjects

Eduardo Lacson

Publications and source records attributed to Eduardo Lacson.

6 recordsLinked to original sources

PubMed2006

The epidemiology of systolic blood pressure and death risk in hemodialysis patients.

BACKGROUND: This study compares the associations of predialysis systolic blood pressure (SBP) with mortality risk in both incident and prevalent hemodialysis (HD) cohorts by using both conventional and time-varying Cox analyses, thus addressing limitations of prior studies. METHODS: A total of 56,338 incident patients starting HD therapy during 1997 to 2001 and 69,590 prevalent HD patients on January 1, 2002, were grouped into the following categories: (1) SBP less than 120 mm Hg, (2) 120 < or = SBP < 140 mm Hg, (3) 140 < or = SBP < 160 mm Hg, (4) 160 < or = SBP < 180 mm Hg, (5) 180 < or = SBP < 200 mm Hg, and (6) SBP of 200 mm Hg or greater. Conventional and time-varying models evaluated 1-year and 3-year (incident patients only) survival. RESULTS: Nine percent and 26.0% of incident patients and 5.7% and 20.1% of prevalent patients were in categories 1 and 2, respectively. Their associated 1-year hazard ratios (HRs) were 2.63 to 3.68 and 1.57 to 1.68 compared with category 4, the reference group. HRs for categories 3, 5, and 6 were not different from category 4. Time-varying models magnified category 1 and 2 HRs to 5.54 to 7.42 and 1.92 to 2.21, such that 25% to 35% of patients in the target SBP range (< 140 mm Hg) had the greatest risk. A "reversed J-shaped" risk profile emerged in the time-varying models, with very high SBP (category 6) associated with HRs of 1.52 to 1.55, but only 1% of patients were in category 6. Three-year outcomes were similar. CONCLUSION: Epidemiological characteristics of predialysis SBP consistently differ from those in the general population despite different analytic perspectives. The data suggest a need for greater investigative, diagnostic, and therapeutic focus on HD patients with normal and prehypertensive blood pressure ranges.

Blood Pressure↗

PubMed2005

Antibody response to Engerix-B and Recombivax-HB hepatitis B vaccination in end-stage renal disease.

Recombivax-HB (REC) and Engerix-B (ENG) are FDA-approved vaccines for hepatitis B virus (HBV) in end-stage renal disease (ESRD). This study compares antibody response rates between them in routine clinical practice. Patients completing the recommended 40 mug dose of REC (3 doses) or ENG (4 doses) between January 1, 2000 to April 30, 2003 were eligible. Patients with prior positive HBV surface antigen (HBsAg) or antibody (HBsAb) test results were excluded. The conversion rate and persistence of protective titer (HBsAb titer>or=10 IU/mL) were tracked for 1 year. A supplemental analysis of a one-to-one matched patient sample was also performed. REC patients (N=885) were older, had longer dialysis vintage, and had a larger proportion of whites than ENG patients (N=13,661). Cumulative conversion response was greater in ENG (58%) than REC (40%) at 1 year (p<0.0001). The odds ratio for response to ENG compared with REC was 1.96 (95% limits: 1.56, 2.45; p<0.0001) adjusted for age, gender, race, diabetes, vintage, BSA, hemoglobin, and eKt/V. Persistent protective HBsAb after 1 year was 77% (ENG) vs. 53% (REC). HBsAg was positive in 208 ENG patients (1.5%) with all but 1 because of transient, vaccine-related antigenemia. The difference in conversion response favoring ENG persisted in a one-to-one sample matched for age, gender, race, modality, and dialysis vintage. The study found higher seroconversion response to ENG compared with REC at several time points up to 1 year. Protective HBsAb disappeared in 23-47% of patients 1 year later, validating CDC recommendations to re-test HBsAb yearly. The observed difference in response rates may be related to the extra ENG dose given at the second month (0, 1, 2, 6 regimen). The study raises a hypothesis that requires confirmation in a prospective clinical trial.

Age Factors↗

PubMed2003

The effects of higher hemoglobin levels on mortality and hospitalization in hemodialysis patients.

BACKGROUND: The introduction of recombinant human erythropoietin for the treatment of anemia of chronic renal failure provided the opportunity to correct anemia in this patient population. The optimal target hemoglobin for patients with end-stage renal disease (ESRD) remains controversial. A large database of hemodialysis patients was analyzed to determine whether increasing hemoglobin level above the current Kidney Dialysis Outcomes Quality Initiative (K/DOQI) recommendations was associated with increased risk of mortality and hospitalization. METHODS: A longitudinal study of hemodialysis patients in Fresenius Medical Care-North America facilities was performed. Selection was restricted to patients in the census for 6 consecutive months from July 1, 1998 through June 30, 2000. Patient mean hemoglobin and other covariates measured during the initial 6 months were related to survival, number of hospitalizations, and length of stay over the subsequent 6 months of follow-up. RESULTS: Patients with hemoglobin <9 g/dL had an adjusted relative risk of death of 2.11 compared to those patients with 11 </= hemoglobin < 12 g/dL (P < 0.0001). The adjusted relative risk of death was 0.84 for 12 </= hemoglobin < 13 g/dL (P = 0.007). These data suggest there is no increased risk of mortality associated with hemoglobin above the current recommended values. Both number of hospitalizations and length of stay decreased as hemoglobin increased. Patients with hemoglobin >/=13 g/dL had an adjusted length of stay of 9.6 days compared to 10.9 days for those with 11 </= hemoglobin < 12 g/dL (P < 0.0001). CONCLUSION: These data indicate the relative risk of death and hospitalization are inversely associated with hemoglobin levels, with no apparent additional risk associated with hemoglobin levels> 12 g/dL.

Adult↗

PubMed2003

Effect of variability in anemia management on hemoglobin outcomes in ESRD.

BACKGROUND: Hemoglobin (Hgb) levels fluctuate in patients with end-stage renal disease over time. This study quantified Hgb level variability and the likelihood of falling within the Hgb level goal range of 11 to 12 g/dL. Implications on the percentage of patients exceeding 3-month rolling average Hgb levels of 12, 12.5, and 13 g/dL were determined. METHODS: Phase I (n = 65,009) tracked patients with Hgb values initially outside the goal range (<11 or >12 g/dL) during 2000. Correlation with facility-specific thresholds also was evaluated. Phase II (n = 48,133) quantified variation in 3-month rolling average Hgb levels in a subset with greater than 10 months of data (mean Hgb, 11.4 +/- 1.3 g/dL). RESULTS: A total of 24,948 patients (38.4%) had Hgb levels between 11 and 12 g/dL. In only 8% did Hgb levels consistently remain less than 11 g/dL, and in 18%, greater than 12 g/dL all year. Twenty-nine percent (18,633 patients) moved from below to above target range or vice versa. Greater mean facility Hgb level correlated with a greater percentage of patients with Hgb levels greater than 10 g/dL (R2 = 0.49) and greater than 12.5 g/dL (R2 = 0.61). For facilities to have 90% or greater of patients with 3-month rolling average Hgb levels greater than 10 g/dL, 13% to 31% of patients will have 3-month rolling average Hgb values greater than 12.5 g/dL. The average individual patient is expected to have a +/-1.4-g/dL fluctuation in 3-month rolling average Hgb levels per year. Despite increased mean Hgb levels and erythropoietin (EPO) and iron use, the spread of the Hgb distribution curve remained unchanged in the last 6 years. CONCLUSION: Variability caused by laboratory assays, biological factors, and therapeutic response determines patient Hgb level variability. Improving factors that can be manipulated (eg, standardizing EPO and iron algorithms) and adjustment of the target Hgb level range, specifically, by increasing the upper bound, likely will decrease the observed variability and further enhance the quality of anemia management.

Anemia↗

PubMedDate not supplied

C-reactive protein and end-stage renal disease.

The significance of CRP and inflammation has increased over time, especially in the end-stage renal disease (ESRD) population. From a simple marker it now appears that CRP is an active participant in pro-atherosclerotic phenomenon including local pro-inflammatory and thrombotic events. Studies in the general population indicate the usefulness of CRP in prognostication and in monitoring response to therapy. The clinical usefulness of CRP monitoring in chronic kidney disease (CKD) and especially in ESRD deserves closer study. In the meantime, the utility of CRP measurements for monitoring and treatment is on a case-by-case basis. Management of traditional cardiovascular risk factors should be considered. In the interest of optimizing therapy it is prudent to use biocompatible membranes and ultrapure water. A careful search for infectious processes in dialysis patients is recommended, with special attention to vascular access sites, periodontitis, gastritis, and other potentially chronic or covert infections. ACE-inhibitor use should be maximized in all eligible CKD patients. The data on the use of statins in ESRD have been generally positive but await further validation. Individualized use for selected patients is probably beneficial.

Anemia↗

PubMedDate not supplied

Dialyzer best practice: single use or reuse?

Outcome studies have shown either no additional risk or a small additional risk for hospitalization and mortality associated with reprocessing dialyzers. Although the risks from reprocessing dialyzers have yet to be fully elucidated, reuse can be done safely if it is performed in full compliance with the standards of Association for the Advancement of Medical Instrumentation (AAMI). Like most industrial processes, however, complete control of the reuse process in a clinical environment and full compliance with regulations at all times is difficult. Potential errors and breakdowns in the reuse process are continuing concerns. The quality controls for reprocessing of dialyzers are not equal to the rigor of the manufacturing process under the purview of the U.S. Food and Drug Administration (FDA). Therefore, if one were to determine "best practice," single use is preferable to reuse of dialyzers based on medical criteria and risk assessment. The long-term and cumulative effects of exposure to reuse reagents are unknown and there is no compelling medical indication for reprocessing of dialyzers. The major impediment when deciding to convert from reuse to single use of dialyzers is economic. The experience in Fresenius Medical Care-North America (FMCNA) facilities demonstrates that converting from a practice of reuse to single use is achievable. However, the overall economic impact of conversion to single use is provider specific. The dominance of reuse has been negated of late by a major shift in practice toward single use. Physicians and patients should be well informed in making decisions regarding the practice of single use versus reuse of dialyzers.

Disinfection↗