Biomedical subjects

Philip J Held

Publications and source records attributed to Philip J Held.

31 records · Page 2Linked to original sources

PubMed2003

Longitudinal assessment of mortality risk among candidates for liver transplantation.

Liver allocation policy recently was modified to use the Model for End-Stage Liver Disease (MELD) for patients with chronic liver disease to stratify potential recipients according to risk for waitlist death. In this study, a retrospective cohort of 760 adult patients with chronic liver disease placed on the liver transplant waitlist between January 1995 and March 2001 and followed up for up to 74 months was studied to assess the ability of the MELD to predict mortality among waitlisted candidates and evaluate the prognostic importance of changes in MELD score over time. Serial MELD scores predicted waitlist mortality significantly better than baseline MELD scores or medical urgency status. Each unit of the 40-point MELD score was associated with a 22% increased risk for waitlist death (P <.001), whereas medical urgency status was not a significant independent predictor. For any given MELD score, the magnitude and direction of change in MELD score during the previous 30 days (DeltaMELD) was a significant independent mortality predictor. Patients with MELD score increases greater than 5 points over 30 days had a threefold greater waitlist mortality risk than those for whom MELD scores increased more gradually (P <.0001). We conclude that mortality risk on the liver transplant waitlist is predicted more accurately by serial MELD score determinations than by medical urgency status or single MELD measurements. DeltaMELD score over time reflects progression of liver disease and conveys important additional prognostic information that should be considered in the further evolution of national liver allocation policy.

Adult↗

PubMed2003

Association of comorbid conditions and mortality in hemodialysis patients in Europe, Japan, and the United States: the Dialysis Outcomes and Practice Patterns Study (DOPPS).

Mortality rates among hemodialysis patients vary greatly across regions. Representative databases containing extensive profiles of patient characteristics and outcomes are lacking. The Dialysis Outcomes and Practice Patterns Study (DOPPS) is a prospective, observational study of representative samples of hemodialysis patients in France, Germany, Italy, Japan, Spain, the United Kingdom, and the United States (US) that captures extensive data relating to patient characteristics, prescriptions, laboratory values, practice patterns, and outcomes. This report describes the case-mix features and mortality among 16,720 patients followed up to 5 yr. The crude 1-yr mortality rates were 6.6% in Japan, 15.6% in Europe, and 21.7% in the US. After adjusting for age, gender, race, and 25 comorbid conditions, the relative risk (RR) of mortality was 2.84 (P < 0.0001) for Europe compared with Japan (reference group) and was 3.78 (P < 0.0001) for the US compared with Japan. The adjusted RR of mortality for the US versus Europe was 1.33 (P < 0.0001). For most comorbid diseases, prevalence was highest in the US, where the mean age (60.5 +/- 15.5 yr) was also highest. Older age and comorbidities were associated with increased risk of death (except for hypertension, which carried a multivariate RR of mortality of 0.74 [P < 0.0001]). Variability in demographic and comorbid conditions (as identified by dialysis facilities) explains only part of the differences in mortality between dialysis centers, both for comparisons made across continents and within the US. Adjustments for the observed variability will allow study of association between practice patterns and outcomes.

Aged↗

PubMed2003

Random sample (DOPPS) versus census-based (registry) approaches to kidney disease research.

This review describes advantages and limitations of registries that base their analyses on the census of all patients. Registries may utilize the random sample approach to enrich their data for more detailed and informative research. The Dialysis Outcomes and Practice Pattern Study (DOPPS) and its random sample approach is discussed here in detail, with examples on the value of this method. The DOPPS is currently being expanded to allow for even more valuable studies. This methodology can also be applied to large countries that do not have an existing registry, as it is an effective way of collecting detailed information at a relatively low cost that is representative of the country or population as a whole.

Censuses↗

PubMed2003

Evaluation of the ESRD managed care demonstration operations.

Individuals with end stage renal disease (ESRD), most of whom are insured by Medicare, are generally prohibited from enrolling in Medicare managed care plans (MCPs). CMS offered ESRD patients the opportunity to participate in an ESRD managed care demonstration mandated by Congress. The demonstration tested whether managed care systems would be of interest to ESRD patients and whether these approaches would be operationally feasible and efficient for treating ESRD patients. This article examines the structure, implementation, and operational outcomes of the three demonstration sites, focusing on: the structure of these managed care programs for ESRD patients, requirements needed to attract and enroll patients, and the challenges of introducing managed care programs in the ESRD arena.

California↗

PubMed2003

Patient selection in the ESRD managed care demonstration.

The Centers for Medicare & Medicaid Service's (CMS') end stage renal disease (ESRD) managed care demonstration offered an opportunity to assess patient selection among a chronically ill and inherently costly population. Patient selection refers to the phenomenon whereby those Medicare beneficiaries who choose to enroll or stay in health maintenance organizations (HMOs) are, on average, younger, healthier, and less costly to treat than beneficiaries who remain in the traditional Medicare fee-for-service (FFS) sector. The results presented in this article show that enrollees into the demonstration were generally younger and healthier than a representative group of comparison patients from the same geographic areas.

Adult↗

PubMed2003

Quality of life and patient satisfaction: ESRD managed care demonstration.

To study the effects of managed care on dialysis patients, we compared the quality of life and patient satisfaction of patients in a managed care demonstration with three comparison samples: fee-for-service (FFS) patients, managed care patients outside the demonstration, and patients in a separate national study. Managed care patients were less satisfied than FFS patients about access to health care providers, but more satisfied with the financial benefits (copayment coverage, prescription drugs, and nutritional supplements) provided under the demonstration managed care plan (MCP). After 1 year in the demonstration, patients exhibited statistically and clinically significant increases in quality of life scores.

California↗

PubMed2003

ESRD managed care demonstration: financial implications.

In 1996, CMS launched the end stage renal disease (ESRD) managed care demonstration to study the experience of offering managed care to ESRD patients. This article analyzes the financial impact of the demonstration, which sought to assess its economic impact on the Federal Government, the sites, and the ESRD Medicare beneficiaries. Medicare's costs for demonstration enrollees were greater than they would have been if these enrollees had remained in the fee-for-service (FFS) system. This loss was driven by the lower than average predicted Medicare spending given the demonstration patients' conditions. The sites experienced losses or only modest gains, primarily because they provided a larger benefit package than traditional Medicare coverage, including no patient obligations and other benefits, especially prescription drugs. Patient financial benefits were approximately $9,000 annually.

Adolescent↗

PubMed2002

Donor characteristics associated with reduced graft survival: an approach to expanding the pool of kidney donors.

BACKGROUND: Availability of cadaveric kidneys for transplantation is far below the growing need, leading to longer waiting time and more deaths while waiting. METHODS: Using national data from 1995 to 2000, we evaluated graft survival by donor characteristics and the rate of discard of retrieved organs, with the goal of increasing use of kidneys that are associated with increased risk of graft failure, that is, expanded donor kidneys. RESULTS: Cox models identified four donor factors that independently predicted significantly higher relative risk of graft loss compared with a low-risk group. These factors included donor age, cerebrovascular accident as the cause of death, renal insufficiency (serum creatinine >1.5 mg/dL), and history of hypertension. Expanded donor kidneys were defined as those with relative risk of graft loss greater than 1.70 and included all donors aged 60 years and older and those aged 50 to 59 years with at least two of the other three conditions (cerebrovascular cause of death, renal insufficiency, hypertension). The expanded donor group accounted for 14.8% of transplanted kidneys. Among organs procured from expanded donors, 38% were discarded versus 9% for all other kidneys. The risk of graft loss of expanded donor kidneys was increased in both older and younger recipients but to a greater extent in those recipients older than 50 years. CONCLUSION: By identifying donor factors associated with graft failure, these analyses may help to expand the number of transplanted kidneys by increasing the utilization of retrieved cadaveric kidneys.

Adolescent↗

PubMed2002

Vascular access use in Europe and the United States: results from the DOPPS.

BACKGROUND: A direct broad-based comparison of vascular access use and survival in Europe (EUR) and the United States (US) has not been performed previously. Case series reports suggest that vascular access practices differ substantially in the US and EUR. We report on a representative study (DOPPS) which has used the same data collection protocol for> 6400 hemodialysis (HD) patients to compare vascular access use at 145 US dialysis units and 101 units in five EUR countries (France, Germany, Italy, Spain, and the United Kingdom). METHODS: Logistic analysis evaluated factors associated with native arteriovenous fistula (AVF) versus graft use or permanent access versus catheter use for prevalent and incident HD patients. Times to failure for AVF and graft were analyzed using Cox proportional hazards regression. RESULTS: AVF was used by 80% of EUR and 24% of US prevalent patients, and was significantly associated with younger age, male gender, lower body mass index, non-diabetic status, lack of peripheral vascular disease, and no angina. After adjusting for these factors, AVF versus graft use was still much higher in EUR than US (AOR=21, P < 0.0001). AVF use within facilities varied from 0 to 87% (median 21%) in the US, and 39 to 100% (median 83%) in EUR. For patients who were new to HD, access use was: 66% AVF in EUR versus 15% in US (AOR=39, P < 0.0001), 31% catheters in EUR vs. 60% in US, and 2% grafts in EUR vs. 24% in US. In addition, 25% of EUR and 46% of US incident patients did not have a permanent access placed prior to starting HD. In EUR, 84% of new HD patients had seen a nephrologist for> 30 days prior to ESRD compared with 74% in the US (P < 0.0001); pre-ESRD care was associated with increased odds of AVF versus graft use (AOR=1.9, P=0.01). New HD patients had a 1.8-fold greater odds (P=0.002) of starting HD with a permanent access if a facility's typical time from referral to access placement was < or =2 weeks. AVF use when compared to grafts was substantially lower (AOR=0.61, P=0.04) when surgery trainees assisted or performed access placements. When used as a patient's first access, AVF survival was superior to grafts regarding time to first failure (RR=0.53, P=0.0002), and AVF survival was longer in EUR compared with the US (RR=0.49, P=0.0005). AVF and grafts each displayed better survival if used when initiating HD compared with being used after patients began dialysis with a catheter. CONCLUSION: Large differences in vascular access use exist between EUR and the US, even after adjustment for patient characteristics. The results strongly suggest that a facility's preferences and approaches to vascular access practice are major determinants of vascular access use.

Adult↗

PubMed2002

Hemodialysis vascular access preferences and outcomes in the Dialysis Outcomes and Practice Patterns Study (DOPPS).

BACKGROUND: Synthetic grafts have generally been found to exhibit lower survival rates and higher complication rates than native arteriovenous fistulae. We investigated whether survival of grafts relative to fistulae was better in facilities with a preference for grafts, hypothesizing that such facilities may place more grafts because grafts produced superior outcomes. METHODS: The study was based on a national U.S. sample of 133 hemodialysis facilities participating in the Dialysis Outcomes and Practice Patterns Study (DOPPS), a prospective, observational study of dialysis treatment practices and outcomes. Vascular access preferences were ascertained from medical directors, nurse managers, and actual practice within each facility (% graft use among prevalent patients). Logistic regression was used to model the odds ratio (OR) of graft placement (vs. fistula) and Cox regression was used to model time from access creation to initial failure. RESULTS: Grafts were preferred by 21% of medical directors and 40% of nurse managers. Patients in facilities in which the medical director or nurse manager expressed a preference for grafts were more than twice as likely to have a graft than a fistula (AOR = 2.3, P < 0.01; reference group = facilities that did not prefer grafts), suggesting that facility preferences influence the type of access created. Overall, grafts were more prevalent than fistulae in dialysis facilities, but displayed a higher relative risk of failure (RR 1.33, P < 0.0001). However, the risk of graft versus fistula failure did not vary by expressed preference of the medical director: the relative risk of graft versus fistula failure was 1.39 in facilities in which the medical director preferred grafts and 1.39 in facilities in which the medical director preferred fistulae. Moreover, the relative risk of graft versus fistula failure was 1.57 in facilities that used more than the median percentage of grafts and 1.19 in facilities that used less than the median percentage of grafts. CONCLUSIONS: No evidence was found that graft outcomes are superior in facilities that prefer grafts to fistulae. The observed variation in vascular access practice patterns suggests opportunities for quality improvement if optimal practices can be defined.

Adult↗

PubMed2002

Mortality risk in hemodialysis patients and changes in nutritional indicators: DOPPS.

BACKGROUND: Nutritional status is strongly associated with outcomes among hemodialysis patients. We analyzed the independent predictive value of several readily measured nutritional indicators, including a modified subjective global assessment (mSGA), body mass index (BMI), serum albumin, serum creatinine, normalized protein catabolic rate (nPCR), serum bicarbonate, lymphocyte count, and neutrophil count, using baseline and six-month follow-up measurements. METHODS: The study sample consisted of 7719 U.S. adult hemodialysis patients enrolled in the international Dialysis Outcomes and Practice Patterns Study (DOPPS), a prospective observational study that includes a random sample of hemodialysis patients from 145 dialysis facilities in the United States. Cox regression was used to estimate the relative risk of mortality associated with differences in measurements at baseline and six months later. Each analysis was adjusted for age, race, sex, and 15 summary comorbid conditions. RESULTS: Lower baseline measurements of mSGA, BMI, serum albumin, serum creatinine, and lymphocyte count were independently associated with significantly higher risk of mortality. During six-month follow-up, decreases in BMI, serum albumin, and serum creatinine were also associated with significantly higher mortality risk. The risk of mortality increased with higher baseline and six-month increases in neutrophil count. CONCLUSIONS: This study confirms that several readily-measured nutritional indicators predict mortality among hemodialysis patients and that changes in indicator values over six months provide additional important prognostic information. Interventions that modify these indicators of nutritional status may have an important impact on the survival of hemodialysis patients.

Aged↗

PubMed2002

Association between vascular access failure and the use of specific drugs: the Dialysis Outcomes and Practice Patterns Study (DOPPS).

BACKGROUND: Several drugs have been proposed to improve vascular access patency based on favorable anticoagulant, antiplatelet, or vascular-remodeling properties. However, there is little evidence to guide drug strategies. METHODS: The association between vascular access patency and the use of specific drugs was studied in a large sample of US hemodialysis patients enrolled in the Dialysis Outcomes and Practice Patterns Study, an international, prospective, observational study. In general, it was assumed that the drugs were prescribed for indications unrelated to vascular access preservation. Primary (unassisted survival) and secondary vascular access patency (assisted survival) were modeled using Cox regression (time to failure) adjusted for age, sex, race, body mass index, incidence to end-stage renal disease, diabetes mellitus, hypertension, valvular disease, chronic obstructive pulmonary disease, aortic aneurysm, deep-vein thrombosis, number of previous permanent accesses, and facility-clustering effects. Fistulae (n = 900) and grafts (n = 1,944) were evaluated separately. Technical failures within the first 30 days of surgical placement were excluded from the analysis. RESULTS: Treatment with calcium channel blockers was associated with improved primary graft patency (relative risk [RR] for failure, 0.86; P = 0.034). Aspirin therapy was associated with better secondary graft patency (RR, 0.70; P < 0.001). Treatment with angiotensin-converting enzyme inhibitors was associated with significantly better secondary fistula patency (RR, 0.56; P = 0.010). Patients administered warfarin showed worse primary graft patency (RR, 1.33; P = 0.037). CONCLUSION: These findings should help guide clinical trial priorities toward vascular access preservation using one or more of the agents that show significant risk reduction for access failure in this study.

Adult↗

PubMed2002

Trends in cadaveric organ donation in the United States: 1990-1999.

Despite declining in-hospital deaths, deceased donor organ donation increased in all demographic segments of the US population from 1990 to 1999. Although the rate of growth in older donors was more dramatic, there was substantial growth in the most physiologically suitable donor age groups, which contribute most to the donor pool. Nationwide, the average annual growth in donation rate for in-hospital deaths ages 1-70 was 5.0%, with wide regional variation. While the national trend is patently inadequate to meet the need for organ transplantation, the wide range of programs aimed at improving organ donation at all levels of society point to an encouraging pattern that may have resulted, in part, from these initiatives.

Adolescent↗