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H I Feldman

Publications and source records attributed to H I Feldman.

At least 19 recordsLinked to original sources
PubMed2001

Effect of the use or nonuse of long-term dialysis on the subsequent survival of renal transplants from living donors.

BACKGROUND: The effect on allograft survival of the transplantation of kidneys from living donors without the previous initiation of long-term dialysis is controversial. METHODS: Using data from the U.S. Renal Data System, we performed a retrospective cohort study of 8481 patients who were or who were not treated by long-term dialysis before receiving a kidney transplant from a living donor. The relative rate of allograft failure for patients who received a transplant without previously undergoing long-term dialysis, as compared with patients who underwent long-term dialysis before transplantation, was assessed by proportional-hazards analysis, with adjustment for potential confounding variables, including the transplantation center and median household income. The association between the receipt of a kidney transplant from a living donor without previous dialysis ("preemptive transplantation") and the risk of biopsy-confirmed acute rejection within six months after transplantation was evaluated by conditional logistic-regression analysis, with adjustment for the transplantation center. RESULTS: Transplantation of a kidney from a living donor without previous long-term dialysis was associated with a 52 percent reduction in the risk of allograft failure during the first year after transplantation (rate ratio, 0.48; P=0.002), an 82 percent reduction during the second year (rate ratio, 0.18; P=0.001), and an 86 percent reduction during subsequent years (rate ratio, 0.14; P=0.001), as compared with transplantation after dialysis. The reduction in the rate of allograft failure during the first year was attenuated when adjustment was made for the timing of acute rejection within the first year (rate ratio, 0.69; 95 percent confidence interval, 0.44 to 1.10; P=0.10). Increasing duration of dialysis was associated with increasing odds of rejection within six months after transplantation (P=0.001). CONCLUSIONS: Preemptive transplantation of kidneys from living donors without the previous initiation of dialysis is associated with longer allograft survival than transplantation performed after the initiation of dialysis.

Adult↗
PubMed2001

Testing the reliability of old and new features of a new electronic monitor for metered dose inhalers.

BACKGROUND: Poor adherence to treatment regimens is hypothesized to be, in part, responsible for the extensive morbidity and mortality associated with asthma. Electronic monitors are the most accurate means available for measuring adherence, but their use has been limited by reports questioning the reliability and validity of their data. OBJECTIVE: To test the reliability and accuracy of the MDILog (Medtrac Technologies, Lakewood, CO), a new electronic monitor of metered dose inhalers (MDIs), and to test its unique features. METHODS: Brief experiments were performed comparing a written diary to the electronic record using three MDILogs. The following features were studied: reporting of time and date of an actuation, recording of the occurrence of an actuation of the MDI, sensing and timing of inhalations, sensing of shaking of the MDI canister, and recording of multiple actuations. RESULTS: Clocking was accurate 100% of the time. Actuation agreed with the paper record 97% to 100%, inhalation 82% to 100%, shaking 86% to 95%. Agreement of late inhalations and multiple actuations with paper records was at least 98%. CONCLUSIONS: The MDILog yields accurate information and is more reliable than previously described monitors. Its new features allow more detailed study of how patients use inhalers by allowing evaluation of how patients inhale and whether they shake the inhaler canister before use.

Administration, Inhalation↗
PubMed2001

Prevalence and determinants of erectile dysfunction in hemodialysis patients.

BACKGROUND: The prevalence of erectile dysfunction (ED) among patients with end-stage renal disease (ESRD) is not known. METHODS: A cross-sectional study was conducted to determine the prevalence of ED among a community-based hemodialysis (HD) population using a two-stage cluster random sampling design. The presence and severity of ED were assessed among 302 ESRD patients using the self-administered International Index of Erectile Function-5 (IIEF-5). Logistic regression was used to examine and test associations between ED and other medical conditions. RESULTS: The prevalence of any level of ED was 82% (95% CI, 76 to 87%) for all HD subjects. The prevalence of severe ED was 45% (CI, 36 to 55%). Subjects younger than 50 years had a prevalence of ED of 63% (CI, 53 to 71%), while in subjects 50 years or older, it was 90% (CI, 84 to 94%). A multivariable analysis demonstrated increasing age (50 to 59, OR = 2.04, 95% CI, 1.3 to 3.1; 60 to 69, OR = 5.5, 95% CI, 1.9 to 15.6) and diabetes (OR = 2.0, 95% CI, 1.2 to 3.3) to be independently associated with the presence of any level of ED. However, neither the subjects' age nor history of diabetes predicted the severity of ED among subjects with ED. The use of angiotensin-converting enzyme inhibitors (ACEIs) was inversely associated with ED (OR = 0.41, 95% CI, 0.17 to 0.98). Poor functional status (Karnofsky score or the Index of Physical Impairment) was not associated with ED. CONCLUSIONS: ED is extremely prevalent among HD patients. Increasing age, diabetes, and nonuse of ACEIs were associated with higher prevalence of ED. The high prevalence of ED was seen even among patients with good functional status.

Adult↗
PubMed2001

Preliminary observations of sildenafil treatment for erectile dysfunction in dialysis patients.

Erectile dysfunction is common in dialysis patients. We report our experience with sildenafil citrate in patients undergoing dialysis therapy. Male subjects attending the Outpatient Dialysis Unit at the University of Pennsylvania (Philadelphia, PA) who were prescribed sildenafil by their primary physician or nephrologist were asked to complete the International Index of Erectile Function before their first dose of sildenafil and after at least 4 weeks of therapy. Subjects' mean age was 50.3 +/- 14.63 (SD) years. Ninety-three percent of the subjects were black. Based on a global efficacy question, 66.7% of the subjects believed that treatment had improved their erections. Subjects reported no increase in the sexual desire domain despite experiencing a significant increase in erectile function, orgasmic function, and satisfaction with intercourse. Sildenafil was well tolerated in a selected group of patients who reported improved sexual function with no major adverse effects.

Adult↗
PubMed2001

Adverse neurologic events associated with rebound hypertension after using short-acting nifedipine in childhood hypertension.

INTRODUCTION: Short-acting nifedipine (SA-NIF) is widely prescribed for acute hypertension (HTN) in children despite reports of ischemic complications in adults. We describe two children with neurologic events caused by rebound hypertension following SA-NIF use. CASES: Patient 1 is a 7-year-old with acute nephritis and blood pressure (BP) of 185/130. She received SA-NIF which decreased BP to 114/79. When BP rebounded to 160/103, she developed severe cortical visual impairment. Head CT demonstrated edema and petechial hemorrhages in the watershed region. Patient 2 is a 10-year-old renal transplant recipient who received SA-NIF for a BP of 155/98, which resulted in a prompt decrease to 114/74. Two hours later he developed aphasia and right-sided neglect. His BP increased to 168/88 and he developed partial complex seizures. Brain MRI showed high signal intensity in the watershed areas with early gadolinium enhancement. DISCUSSION: The temporal association of the neurologic events with the rebound increase in BP suggests a possible role for the SA-NIF, consistent with its pharmacokinetic profile. Although the adult literature has focused on the unpredictable decline in BP after SA-NIF treatment, these cases suggest that rapid increases in BP following the maximal SA-NIF effect may be associated with impaired cerebral autoregulation and encephalopathy in children. These cases underscore the need for frequent blood pressure determinations and therapy to prevent rebound hypertension.

Child↗
PubMed2000

Arterial hypertension and renal allograft survival.

CONTEXT: Several observational studies have investigated the significance of hypertension in renal allograft failure; however, these studies have been complicated by the lack of adjustment for baseline renal function, leaving the role of elevated blood pressure in allograft failure unclear. OBJECTIVE: To examine the relationship between blood pressure adjusted for renal function and survival after cadaveric allograft transplantation. DESIGN: Nonconcurrent historical cohort study conducted from 1985 through 1997. SETTING: University teaching hospital. PARTICIPANTS: A total of 277 patients aged 18 years or older who underwent cadaveric renal transplantation without another simultaneous organ transplantation and whose allograft was functioning for a minimum of 1 year. Follow-up continued through 1997 (mean follow-up, 5.7 years). MAIN OUTCOME MEASURE: Time to allograft failure (defined as death, return to dialysis, or retransplantation) by systolic, diastolic, and mean arterial blood pressure measurements at 1 year after transplantation. RESULTS: Multivariate Cox proportional hazards modeling demonstrated that nonwhite ethnicity, history of acute rejection, and nondiabetic kidney disease were significant predictors of failure (P = .01 for all). In addition, the calculated creatinine clearance at 1 year had an adjusted rate ratio (RR) for allograft failure per 10 mL/min (0.17 mL/s) of 0.74 (95% confidence interval [CI], 0.62-0.88). The RR per 10-mm Hg increase in blood pressure measured at 1 year after transplantation, after adjustment for creatinine clearance, was 1.15 (95% CI, 1.02-1.30) for systolic pressure, 1.27 (95% CI, 1.01-1.60) for diastolic pressure, and 1.30 (95% CI, 1.05-1.61) for mean arterial pressure. Supplemental analyses that did not include death as a failure event or reduce the minimum allograft survival time for study subjects to 6 months yielded results consistent with the primary analysis. There was no evidence of modification of the blood pressure-allograft failure relationship by ethnicity or diabetes mellitus. CONCLUSIONS: Systolic, diastolic, and mean arterial blood pressures at 1 year posttransplantation strongly predict allograft survival adjusted for baseline renal function. More aggressive control of blood pressure may prolong cadaveric allograft survival.

Adult↗
PubMed2000

Dialyzer reuse: an evolving search for efficiency.

The evolution of dialyzer reuse in the United States provides an opportunity to examine the dialysis community's response to changing financial conditions and incentives. As background, we provide a conceptual framework to explain the factors governing the diffusion of dialysis technologies and then describe the clinical context in which reuse programs have developed. Early in its evolution, dialyzer reuse arose principally from the desire to reduce costs under a system of capitated payments. More recently, despite evidence of an adverse health effect, cost-savings from reuse have permitted the adoption of new and expensive technologies. The net effect of the tradeoff's between cost and quality should, ideally, drive the decision to reuse dialyzers. However, even if such tradeoffs can be fully characterized, incentives to implement efficiencies created by capitated systems of payment will continue to influence practice.

Equipment Reuse↗
PubMed1999

Potential utility of electronic drug compliance monitoring in measures of adverse outcomes associated with immunosuppressive agents.

Poor compliance with prescribed medications limits the effectiveness of many pharmacologic therapies and enhances their potential toxicities. Traditional methods of measuring drug-taking behavior, including direct observation, patient self-report, pill counts, and therapeutic drug level monitoring, all have well-described limitations in validity and interpretability. Electronic medication event monitoring has been used to assess compliance with therapies for hypertension, glaucoma, anemia, and epilepsy, overcoming many problems of traditional approaches. However, no published reports describe the use of electronic monitoring with immunosuppressive agents, despite their increasing use for non-life-threatening conditions and their many dose-dependent toxicities. Transplant recipients are thought to be at particular risk from noncompliance. Therefore, we undertook this study to assess the feasibility of electronically monitoring compliance with immunosuppressive drugs among renal allograft recipients. Twenty-five kidney transplant patients receiving immunosuppressive medications from a single pharmacy were enrolled. Each subject received electronic monitors with their immunosuppressive serum drug refills for cyclosporine and azathioprine. Each subject returned their monitors after the first month of this 2-month study for downloading data. The frequency distribution of interdose intervals were described. Two measures of average non-compliance were calculated for both drugs: the proportion of monitored days that had missed doses, and the proportion of missed doses. Once daily and twice daily regimens of cyclosporine were compared. Concordance in drug compliance between the two drugs was calculated for each subject and averaged over the study population. Twenty-two of 25 subjects missed one or more doses of cyclosporine or azathioprine. Seventeen (68%) subjects never missed four or more consecutive doses. Subjects were non-compliant with cyclosporine on 8.7% of monitored days, and non-compliance with azathioprine on 9.8% of monitored days. Subjects were non-compliant with 6.8% of their cyclosporine doses and 9.8% of their azathioprine doses. Patients were compliant with both drugs on 86.6% of days and were non-compliant with both drugs on 5.1% of days. Subjects were non-compliant with cyclosporine during 5% and 13.2% of monitored days for once and twice daily dosing regimens, respectively. Concordance analysis demonstrated that for 91.7% of days of monitoring, compliance information was identical for both drugs. This study demonstrated the feasibility of electronic medication event monitoring among kidney transplant patients. This methodology represents an important tool for monitoring compliance of immunosuppressive agents essential to their safe and effective use, and should be considered for use in future studies of these drugs and others with substantial dose-dependent toxicity.

Journal Article↗
PubMed1999

Discrepancies in pediatric bone mineral density reference data: potential for misdiagnosis of osteopenia.

OBJECTIVE: To evaluate published pediatric dual-energy x-ray absorptiometry bone mineral density (BMD) reference data by comparing the diagnostic classification of measured BMD in children at risk for osteopenia as healthy or osteopenic according to reference source. STUDY DESIGN: Spine BMD was measured in 95 children, ages 9 to 15 years, at risk for osteopenia because of childhood disease. The BMD results were converted to age-specific z scores for each of the 5 reference data sets, and the z -score distributions were compared. RESULTS: Between 11% and 30% of children were classified as osteopenic (z score < -2.0) depending on the reference data set. The 2 sex-specific reference data sets yielded similar diagnostic classification of boys and girls: 10% of boys and 11% to 16% of girls were osteopenic (P =.4). The 3 sex-nonspecific reference data sets classified 9% to 13% of girls and 24% to 44% of boys as osteopenic; the diagnosis of osteopenia was significantly greater in boys (P <.01). CONCLUSIONS: The use of different published reference data for the assessment of children at risk for osteopenia results in inconsistent diagnostic classification of BMD results. These inconsistencies can be partially attributed to sex-nonspecific reference data that result in misclassification of boys as osteopenic.

Absorptiometry, Photon↗
PubMed1999

Effect of anti-lymphocyte antibody induction therapy on renal allograft survival.

Our two meta-analyses show that antilymphocyte antibody induction therapy extends allograft survival when compared to induction therapy with cyclosporine, azathioprine, and prednisone with the majority of the benefit seen during the first 2 years after transplant. The benefit of induction therapy with respect to allograft survival is particularly important among patients with pretransplant panel reactive antibodies greater than 20%. Although our understanding of the role of antilymphocyte antibody induction therapy continues to evolve, these two meta-analyses provide evidence for its use in clinical renal transplantation.

Adolescent↗
PubMed1999

Association of dialyzer reuse with hospitalization and survival rates among U.S. hemodialysis patients: do comorbidities matter?

The objective of this study was to determine whether the associations between reuse of hemodialyzers and higher rates of death and hospitalization persist after adjustment for comorbidity. This was a nonconcurrent cohort study of survival and hospitalization rates among 1491 U.S. chronic hemodialysis patients beginning treatment in 1986 and 1987. The impact of dialyzer reuse was compared across three survival models: an unadjusted model, a "base" model adjusted only for demographics and renal diagnosis, and an "augmented" model additionally adjusted for comorbidities. We found that reuse of dialyzers was associated with a similarly higher rate of death in analyses unadjusted for confounders (relative risk [RR] 1.25, 95% confidence interval [CI] 0.97-1.61), adjusted for demographics and renal diagnosis (RR 1.16, 95% CI 0.96-1.41), and analyses additionally adjusted for comorbidities (RR = 1.25, CI, 1.03, 1.52). Reusing dialyzers was also associated with a greater rate of hospitalization that was stable regardless of adjustment procedures. We conclude that higher rates of death and hospitalization associated with dialyzer reuse persist regardless of adjustment for demographic characteristics or baseline comorbidities. These findings amplify concerns that there exists elevated morbidity among hemodialysis patients treated in facilities that reuse hemodialyzers. Although the association we observed was not confounded by comorbidity, a cause-and-effect relationship between dialyzer reuse and morbidity could not be proved because of the inability to control for aspects of care other than dialyzer reuse.

Adult↗
PubMed1999

US, CT, and MR evaluation of accessory renal arteries and proximal renal arterial branches.

RATIONALE AND OBJECTIVES: The purpose of this study was to compare color Doppler ultrasound (US), computed tomographic (CT) angiography, and magnetic resonance (MR) angiography for the evaluation of accessory renal arteries and proximal branches of the main renal artery. MATERIALS AND METHODS: Fifty-six subjects who had undergone conventional arteriography of the renal arteries participated in a prospective comparison of Doppler US (45 patients), CT angiography (52 patients), and nonenhanced MR angiography (28 patients). Conventional arteriography depicted 28 accessory renal arteries and 21 proximal branches of the main renal artery within 2 cm of the aorta. RESULTS: US depicted five of 24 accessory renal arteries seen at arteriography but no proximal arterial branches. CT angiography depicted 24 of 26 accessory renal arteries and 13 of 17 proximal arterial branches, as well as 15 additional accessory renal arteries not seen at conventional arteriography. MR demonstrated 11 of 15 accessory arteries, as well as four additional accessory arteries not seen at conventional arteriography. MR did not depict any of nine proximal arterial branches seen at conventional arteriography. CONCLUSION: When compared with US or nonenhanced MR angiography, CT is the preferred method for evaluation of accessory renal arteries and proximal branches of the renal artery.

Adult↗
PubMed1999

Membranoproliferative glomerulonephritis type I, mixed cryoglobulinemia and lymphoma in the absence of hepatitis C infection.

Chronic hepatitis C virus infection has been linked to cryoglobulinemia, membranoproliferative glomerulonephritis, and malignant B-cell lymphoproliferation, suggesting a possible pathogenetic link between these disorders. We report a patient with the latter clinical triad in the absence of hepatitis C infection. We postulate that the persistent and dysregulated immunologic activity associated with chronic antigen stimulation, inflammation and/or B-cell malignancy induces nephritogenic autoantibodies, including cryoglobulins, that produce a similar clinical syndrome in genetically susceptible individuals.

Biopsy, Needle↗
PubMed1999

Association of dialyzer reuse and hospitalization rates among hemodialysis patients in the US.

OBJECTIVES: To determine if reuse of hemodialyzers is associated with higher rates of hospitalization and their resulting costs among end-stage renal disease (ESRD) patients. METHODS: Noncurrent cohort study of hospitalization rates among 27,264 ESRD patients beginning hemodialysis in the United States in 1986 and 1987. RESULTS: Dialysis in free-standing facilities reprocessing dialyzers was associated with a greater rate of hospitalization than in facilities not reprocessing (relative rate (RR) = 1.08, 95% confidence interval (CI), 1.02-1.14). This higher rate of hospitalization was observed with dialyzer reuse using peracetic/acetic acids (RR = 1.11, CI 1. 04-1.18) and formaldehyde (RR = 1.07, CI 1.00-1.14), but not glutaraldehyde (p = 0.97). There was no difference among hospitalization rates in hospital-based facilities reprocessing dialyzers with any sterilant and those not reprocessing. Hospitalization for causes other than vascular access morbidity in free-standing facilities reusing dialyzers with formaldehyde was not different from hospitalization in facilities not reusing. However, reuse with peracetic/acetic acids was associated with higher rates of hospitalization than formaldehyde (RR = 1.08, CI 1.03-1.15). CONCLUSIONS: Dialysis in free-standing facilities reprocessing dialyzers with peracetic/acetic acids or formaldehyde was associated with greater hospitalization than dialysis without dialyzer reprocessing. This greater hospitalization accounts for a large increment in inpatient stays in the USA. These findings raise important concerns about potentially avoidable morbidity among hemodialysis patients.

Cohort Studies↗
PubMed1998

The effect of antilymphocyte induction therapy on renal allograft survival. A meta-analysis of individual patient-level data. Anti-Lymphocyte Antibody Induction Therapy Study Group.

PURPOSE: Randomized, controlled trials have not shown that the perioperative use of antilymphocyte antibodies (induction therapy) improves survival of cadaveric kidney allografts. This study combined individual patient-level data from published trials to examine the effect of induction therapy on allograft survival. DATA SOURCES: Randomized, controlled trials identified from MEDLINE. STUDY SELECTION: Published trials that compared adult recipients of cadaveric renal allografts who did and did not receive antilymphocyte antibodies in the perioperative period were selected if individual patient-level data were available. DATA EXTRACTION AND ANALYSIS: Individual patient-level data were collected for each of 628 study patients. Multivariable Cox proportional hazards regression was used to estimate the effect of induction therapy on allograft survival. RESULTS: The adjusted rate ratio for allograft failure with induction therapy compared with conventional therapy was 0.62 (95% CI, 0.43 to 0.90) (P = 0.012) over 2 years and 0.82 (CI, 0.62 to 1.09) (P = 0.17) over 5 years. The effect of induction therapy on allograft survival diminished over time; no benefit overall was seen after 2 years after transplantation (rate ratio, 1.13 [CI, 0.72 to 1.78]) (P > 0.2). Greater HLA-DR mismatch, delayed allograft function, diabetes mellitus in the recipient, African-American ethnicity of the recipient, and presensitization (panel-reactive antibody levels > or = 20%) were significantly associated with allograft failure at 5 years. Among high-risk patients, only those who were presensitized benefited from induction therapy at 2 years (rate ratio, 0.12 [CI, 0.03 to 0.44]) (P = 0.001). Results were similar at 5 years. CONCLUSIONS: Using individual-level data, this study showed a benefit of induction therapy at 2 years, particularly among presensitized patients. Although the benefit of this therapy subsequently waned, presensitized patients continued to have benefit at 5 years.

Adolescent↗
PubMed1998

Comparison of Doppler US and CT angiography for evaluation of renal artery stenosis.

RATIONALE AND OBJECTIVES: The authors compared Doppler ultrasound (US) with computed tomographic (CT) angiography in the evaluation of stenosis of the main renal artery. MATERIALS AND METHODS: Fifty-six patients who had undergone conventional angiography of the renal arteries participated in a prospective comparison of Doppler US (45 patients) and CT angiography (52 patients). US evaluation included both the main renal artery and segmental renal arteries. RESULTS: There were 27 main renal arteries with at least 50% stenosis in 20 patients. In 36 patients, there was no significant stenosis. All cases of main renal artery stenosis detected with Doppler US of the segmental arteries were also identified with Doppler US of the main renal artery. The by-artery sensitivity (63%) of US of the main renal artery was greater than that (33%) of US of the segmental arteries. CT angiography was more sensitive (96%) than Doppler US (63%) in the detection of stenosis, but the specificity of CT (88%) was similar to that of US (89%). The difference in the area under the receiver operating characteristic curve (AUC) between CT (AUC = 0.94) and US (AUC = 0.82) was statistically significant (P = .038). CONCLUSION: Doppler US of the main renal artery is more sensitive than Doppler US of segmental arteries in the detection of stenosis. CT angiography is more accurate than Doppler US in the evaluation of renal artery stenosis.

Adult↗
PubMed1998

Race and delayed kidney allograft function.

BACKGROUND: Allograft survival among black recipients is poorer than among whites. Delayed allograft function is associated with a significant reduction in renal allograft survival. The relationship between delayed allograft function and black race is incompletely specified and was the focus of this investigation. METHODS: A non-concurrent study of 325 recipients of cadaveric allografts followed for the occurrence of delayed allograft function defined as dialysis during the first week following transplantation for the principal analysis. A secondary definition of delayed allograft function was formulated based on the serum creatinine 2 weeks after transplantation. Unadjusted and adjusted logistic regression analysis were used to examine the unconfounded relationship between race and delayed allograft function. RESULTS: Fifty-seven of 91 (62.6%) black recipients experienced delayed allograft function compared to 113 of 234 (48.3%) whites. The odds ratio for black race as a predictor of delayed allograft function was 1.80, P=0.02, (95% CI, 1.09, 2.95). This finding was stable despite adjustment for other predictors of delayed allograft function in a multivariate model, but the precision of this estimate was less (P=0.10) because of missing data. Additionally, adjusted models with imputed values for missing covariates, models using a secondary definition of delayed allograft function, and models excluding patients whose cyclosporin therapy was delayed, all consistently demonstrated a similar association between black race and delayed allograft function. CONCLUSIONS: This study demonstrated an increased risk of delayed allograft function among black recipients. This relationship may play a role in the poorer allograft outcomes experienced by black recipients. Given the negative effect of delayed allograft function on allograft survival, efforts to identify its modifiable risk factors should be a high priority.

Adult↗