Solid-organ transplantation in older adults: current status and future research.

An increasing number of patients older than 65 years are referred for and have access to organ transplantation, and an increasing number of older adults are donating organs. Although short-term outcomes are similar in older versus younger transplant recipients, older donor or recipient age is associated with inferior long-term outcomes. However, age is often a proxy for other factors that might predict poor outcomes more strongly and better identify patients at risk for adverse events. Approaches to transplantation in older adults vary across programs, but despite recent gains in access and the increased use of marginal organs, older patients remain less likely than other groups to receive a transplant, and those who do are highly selected. Moreover, few studies have addressed geriatric issues in transplant patient selection or management, or the implications on health span and disability when patients age to late life with a transplanted organ. This paper summarizes a recent trans-disciplinary workshop held by ASP, in collaboration with NHLBI, NIA, NIAID, NIDDK and AGS, to address issues related to kidney, liver, lung, or heart transplantation in older adults and to propose a research agenda in these areas.

Impact of Medicare coverage on disparities in access to simultaneous pancreas and kidney transplantation.

In the setting of disparities in access to simultaneous pancreas and kidney transplantation (SPKT), Medicare coverage for this procedure was initiated July 1999. The impact of this change has not yet been studied. A national cohort of 22 190 type 1 diabetic candidates aged 18-55 for kidney transplantation (KT) alone or SPKT was analyzed. Before Medicare coverage, 57% of Caucasian, 36% of African American and 38% of Hispanic type 1 diabetics were registered for SPKT versus KT alone. After Medicare coverage, these proportions increased to 68%, 45% and 43%, respectively. The overall increase in SPKT registration rate was 27% (95% CI 1.16-1.38). As expected, the increase was more substantial in patients with Medicare primary insurance than those with private insurance (Relative Rate 1.18, 95% CI 1.09-1.28). However, racial disparities were unaffected by this policy change (African American vs. Caucasian: 0.97, 95% CI 0.87-1.09; Hispanic vs. Caucasian: 0.94, 95% CI 0.78-1.05). Even after Medicare coverage, African Americans and Hispanics had almost 30% lower SPKT registration rates than their Caucasian counterparts (95% CI 0.66-0.79 and 0.59-0.80, respectively). Medicare coverage for SPKT succeeded in increasing access for patients with Medicare, but did not affect the substantial racial disparities in access to this procedure.

The association of state and national legislation with living kidney donation rates in the United States: a national study.

The effect of state legislation and federal policies supporting living donors on living kidney donation rates in the United States is unknown. We studied living kidney donation rates from 1988 to 2006, and we assessed changes in donation before and after the enactment of state legislation and the launch of federal initiatives supporting donors. During the study, 27 states enacted legislation. Among states enacting legislation, there was no statistically significant difference in the average rate of increase in overall living kidney donations after compared to before state legislation enactment (annual increase in donations per 1 000 000 population [95% confidence interval] 2.39 [1.94-2.84] compared to 1.68 [0.89-2.47] respectively, p > 0.05). Among states not enacting legislation, there was a statistically significantly greater annual increase in overall donation rates from 1997 to 2002 compared to before 1997 when federal initiatives commenced, but there was no growth in annual rates after 2002. State and federal legislation were associated with increases in living-unrelated donation. These findings suggest that although existing public policies were not associated with improvements in the majority of donations from living-related donors, they may have had a selective effect on barriers to living-unrelated kidney donation.

WITHDRAWN: Anticoagulants or antiplatelet therapy for non-rheumatic atrial fibrillation and flutter.

BACKGROUND: Atrial fibrillation (AF) carries a high risk of stroke and other thromboembolic events. Appropriate use of drugs to prevent thromboembolism in patients with AF involves comparing the patient's risk of stroke to the risk of hemorrhage from medication use. OBJECTIVES: To quantify risk of stroke, major hemorrhage and death from using medications that have been rigorously evaluated for prevention of thromboembolism in AF. SEARCH STRATEGY: Articles were identified through the Cochrane Collaboration's CENTRAL database and MEDLINE until December 1999. SELECTION CRITERIA: Included Randomized controlled trials of drugs to prevent thromboembolism in adults with non-postoperative AF. Excluded RCTS of patients with rheumatic valvular disease. DATA COLLECTION AND ANALYSIS: Data were abstracted by two reviewers. Odds ratios from all qualitatively similar studies were combined, with weighting by study size, to yield aggregate odds ratios for stroke, major hemorrhage, and death for each drug. MAIN RESULTS: Fourteen articles were included in this review. Warfarin was more efficacious than placebo for primary stroke prevention {aggregate odds ratio (OR) of stroke=0.30 [95% Confidence Interval (C.I.) 0.19,0.48]}, with moderate evidence of more major bleeding { OR= 1.90 [95% C.I. 0.89,4.04].}. Aspirin was inconclusively more efficacious than placebo for stroke prevention {OR=0.68 [95% C.I. 0.29,1.57]}, with inconclusive evidence regarding more major bleeds {OR=0.81[95% C.I. 0.37,1.78]}. For primary prevention, assuming a baseline risk of 45 strokes per 1000 patient-years, warfarin could prevent 30 strokes at the expense of only 6 additional major bleeds. Aspirin could prevent 17 strokes, without increasing major hemorrhage. In direct comparison, there was moderate evidence for fewer strokes among patients on warfarin than on aspirin {aggregate OR=0.64[95% C.I. 0.43,0.96]}, with only suggestive evidence for more major hemorrhage {OR =1.58 [95% C.I. 0.76,3.27]}. However, in younger patients, with a mean age of 65 years, the absolute reduction in stroke rate with warfarin compared to aspirin was low (5.5 per 1000 person-years) compared to an older group (15 per 1000 person-years). Low-dose warfarin or low-dose warfarin with aspirin was less efficacious for stroke prevention than adjusted-dose warfarin. AUTHORS' CONCLUSIONS: The evidence strongly supports warfarin in AF for patients at average or greater risk of stroke, although clearly there is a risk of hemorrhage. Although not definitively supported by the evidence, aspirin may prove to be useful for stroke prevention in sub-groups with a low risk of stroke, with less risk of hemorrhage than with warfarin. Further studies are needed of low- molecular weight heparin and aspirin in lower risk patients.

Prevalence of immune thrombocytopenia: analyses of administrative data.

BACKGROUND: The prevalence of immune thrombocytopenic purpura (ITP) in the USA is unknown. The paucity of data makes clinical trial design and resource allocation challenging. OBJECTIVES: We aimed to quantify the prevalence of ITP in one state and to report on utilization of resources. METHODS: The Maryland Health Care Commission supplied utilization data on all privately insured Maryland residents in 2002. We identified patients having two claims, separated by at least 30 days, for International Classification of Diseases, Ninth Revision, Clinical Modification code 287.3 (expected to be predominantly ITP). We excluded patients with concurrent diagnoses that made ITP unlikely. In sensitivity analyses, we varied the required visit interval between 14 and 180 days. We quantified ITP prevalence, resource utilization, and prevalence of concurrent autoimmune illnesses. RESULTS: The age-adjusted prevalence of ITP was 9.5 per 100,000 persons (10.5 per 100,000 when requiring a minimum 14-day interval and 4.5 per 100,000 with a 180-day interval). There was a predominance of males in childhood and of females in the middle-adult years, with an overall prevalence rate ratio of 1.9 for females to males. Twenty per cent of these patients were hospitalized, but emergency department use was rare, as was splenectomy. A concurrent diagnosis of multiple sclerosis was 25 times more prevalent than anticipated. CONCLUSIONS: We conclude that the prevalence of ITP in one populous state in the USA is comparable with that which has been reported in Europe. The suggested co-occurrence of ITP and multiple sclerosis in children merits further investigation.

Lack of benefit for intravenous thrombolysis in patients with myocardial infarction who are older than 75 years.

BACKGROUND: The benefit of intravenous thrombolytic therapy in elderly patients with myocardial infarction is uncertain. There are no randomized trials of thrombolytic efficacy or observational studies of clinical effectiveness that focus specifically on the elderly. METHODS AND RESULTS: To determine whether thrombolytic therapy for elderly patients is associated with a survival advantage in a large observational database, we conducted a retrospective cohort study of 7864 Medicare fee-for-service patients aged 65 to 86 years with the primary discharge diagnosis of acute myocardial infarction who were admitted with clinical and ECG indications for thrombolytic therapy and no absolute contraindications. The study included all US acute care nongovernment hospitals without on-site angioplasty capability. Using proportional-hazards methods, we found that in a comprehensive multivariate model, there was a significant interaction (P<0.001) between age and the effect of thrombolytic therapy on 30-day mortality rates. For patients 65 to 75 years old, thrombolytic therapy was associated with a survival benefit, consistent with randomized trials. Among patients aged 76 to 86 years, thrombolytic therapy was associated with a survival disadvantage, with a 30-day mortality hazard ratio of 1.38 (95% CI 1. 12 to 1.71, P=0.003). For these patients, there was no benefit from thrombolytic therapy in any clinical subgroup. CONCLUSIONS: In nationwide clinical practice, thrombolytic therapy for patients >75 years old is unlikely to confer survival benefit and may have a significant survival disadvantage. Reperfusion research that is focused on elderly patients is urgently needed.

Net costs from three perspectives of using low versus high osmolality contrast medium in diagnostic angiocardiography.

OBJECTIVES: We conducted an economic analysis to assess the extent to which a reduction in adverse drug reactions induced by low osmolality compared with high osmolality contrast media during diagnostic angiocardiography would result in savings to hospitals, society and third-party payers that would offset the substantially higher price of low osmolality contrast medium. BACKGROUND: Substitution of low osmolality for high osmolality contrast media in the approximately 1 million diagnostic angiocardiographic procedures performed each year in the United States could substantially increase health care costs. Cost-effectiveness estimates should include savings that might occur through reduced costs of managing adverse drug reactions. METHODS: In a randomized clinical trial of 505 persons under-going diagnostic angiography with either high osmolality or low osmolality contrast medium, we measured and compared 1) material costs of contrast media, and 2) costs from three perspectives of incremental resources used to manage contrast-related adverse drug reactions. We also performed sensitivity analyses to examine the effect of different assumptions with regard to relative risk, absolute risk and costs of adverse drug reactions on estimates of net cost of use of high osmolality and low osmolality contrast media. RESULTS: One-hundred thirty-seven (54.2%) of 253 patients receiving high osmolality contrast medium and 44 (17.5%) of 252 patients receiving low osmolality contrast medium experienced adverse drug reactions. The average cost (from society's perspective) of resources used to manage adverse drug reactions per patient undergoing angiography was significantly (p = 0.0001) greater for high osmolality (mean $249) versus low osmolality (mean $92) contrast medium. Differential costs (from the hospital's perspective) were $67 greater for high osmolality contrast medium. Charges and professional fees (from the payer's perspective) were $182 greater for high osmolality (mean $312) than for low osmolality (mean $130) contrast medium (p = 0.42, NS). The higher differential and average costs of managing adverse drug reactions with high osmolality contrast medium offset 33% and 75%, respectively, of the $207 difference in mean material costs, but these estimates are sensitive to infrequent high cost cases. CONCLUSIONS: Although low osmolality contrast medium is not cost-saving in diagnostic angiocardiography, its higher price is partially offset by lower management costs of adverse drug reactions. The cost offset for the hospital is lower than that for society and may not be realized by third-party payers. These methods and results may be useful in establishing clinical and payment guidelines for use of alternative contrast media in diagnostic angiocardiography.

Cost and procedure implications of thrombolytic therapy for acute myocardial infarction.

A computer model was developed to analyze the costs to Medicare and the potential procedure volume associated with alternative strategies for treatment of acute myocardial infarction. The expected cost per case to Medicare for initial hospitalization was approximately $7,200 for conventional treatment, $7,900 for treatment with intravenous streptokinase and $8,400 for treatment with recombinant tissue-type plasminogen activator (rt-PA). The expected cost per case for use of streptokinase or rt-PA in combination with cardiac catheterization performed either emergently or at 48 h was in excess of $11,000. These cost estimates do not reflect the cost of thrombolytic drugs themselves because Medicare has not adjusted its hospital payment rates to take account of such costs. Although both streptokinase and rt-PA will increase costs to Medicare for hospitalizations for acute myocardial infarction, both agents will do so at a reasonably low cost per additional life saved--between $50,000 and $60,000. Emergency and 48 h catheterization strategies are considerably less cost-effective. Regarding procedures, this model suggests that for every 1,000 patients treatment with streptokinase will result in an additional 76 coronary angioplasty procedures and 26 coronary artery bypass operations, whereas treatment with rt-PA will result in an additional 122 angioplasty procedures and 43 bypass operations compared with conventional treatment. Thrombolytic treatment is thus likely to increase substantially the volume of cardiac catheterization, coronary angioplasty and coronary artery bypass surgery performed in the United States.

The impact of practice guidelines in the management of Barrett esophagus: a national prospective cohort study of physicians.

BACKGROUND: Surveillance of patients with Barrett esophagus (BE) is recommended to detect dysplasia and early cancer. In 1998, practice guidelines for the surveillance of patients with BE were developed under the auspices of the American College of Gastroenterology (ACG). Our objective is to assess physicians' awareness of agreement with and adherence to these guidelines. METHODS: A national prospective cohort study of practicing gastroenterologists who completed a self-administered questionnaire containing case studies prior to the release of the guidelines and another survey 18 months later. Analysis of adherence to the guidelines was done using the McNemar chi(2) test. RESULTS: Of the 154 gastroenterologists (66%) who responded to the follow-up survey, more than half (55%) were aware of the guidelines, and members of the ACG were more likely to know of their existence than nonmembers (61% vs 38%; P =.01). Overall, about 27% of physicians reported practicing in accordance with the guidelines at baseline; adherence increased modestly to 38% in the 18-month follow-up (P =.04) and was inversely related to fee-for-service reimbursement. Awareness was not associated with an increased likelihood of adherence, but agreement with the guidelines was strongly correlated with adherence (P<.001). The most frequent reasons for disagreement were concerns about liability, cancer risk, and inadequate evidence. CONCLUSIONS: Awareness of the guidelines published by the ACG was low. Guideline awareness did not predict adherence. Improvement in guideline adherence will require steps beyond mere dissemination and promotion. Addressing disagreements about liability, disease risk, and scientific evidence as well as restructuring payment incentives may help achieve optimal practice.

Patterns of expenditures and use of services among older adults with diabetes. Implications for the transition to capitated managed care.

OBJECTIVE: To examine health care use and expenditures among older adults with diabetes, investigate factors that are associated with higher expenditures, and describe the policy implications of caring for this population under managed care. RESEARCH DESIGN AND METHODS: A cross-sectional analysis of expenditures for individuals with diabetes over age 65 years from a nationwide 5% random sample of Medicare beneficiaries was conducted during 1992. All components of medical care covered under Medicare were examined. Multivariate analysis was used to assess the contribution of age, race, sex, number of diabetic complications, and comorbidity (Charlson Index) on total expenditures. RESULTS: On average, individuals with diabetes (n = 188,470) were 1.5 times (P < 0.0001) as expensive as all Medicare beneficiaries (n = 1,371,960). However, there were wide variations, with the most expensive 10% of beneficiaries with diabetes accounting for 56% of expenditures for individuals with diabetes and the least expensive 50% accounting for 4%. Acute care hospitalizations accounted for the majority (60%) of total expenditures, whereas outpatient and physician services accounted for 7 and 33%, respectively. There were no differences in the number of complications for all older adults with diabetes compared with those with the highest expenditures. However, the average number of hospitalizations was 1.6 times (0.53 vs. 0.34; P < 0.0001) higher, and the average length of stay was 2 days longer, among older adults with diabetes (P < 0.0001). In the regression model, age and male sex (factors currently used to set payment rates for Medicare managed care enrollees), and number of diabetic complications, but not race, were positively related to expenditures, yet had minimal predictive power (R2 = 0.0006). The addition of the Charlson Index, also positively related to expenditures, was able to explain up to 20% of the variation in total expenditures (R2 = 0.196). CONCLUSIONS: There are large variations in expenditures among older adults with diabetes. Because elderly beneficiaries with diabetes are more expensive than the average older adult, current Medicare capitation rates may be inadequate. To avoid selection bias and under-treatment of this vulnerable population under managed care, methods to construct fair payment rates and safeguard quality of care are desirable.

Predicting expenditures for Medicare beneficiaries with diabetes. A prospective cohort study from 1994 to 1996.

OBJECTIVE: To describe health care expenditures and utilization patterns among older adults with diabetes and to examine factors associated with expenditures over a 3-year period. RESEARCH DESIGN AND METHODS: We conducted a prospective cohort study of health care expenditures and utilization by diabetic patients from a random nationwide sample of aged Medicare beneficiaries from 1994 to 1996. All services covered by the Medicare program were examined. Multivariate regression was used to assess the contribution of patient characteristics in 1994 on Part B, inpatient, and total expenditures in 1995 and 1996. RESULTS: Per capita expenditures for beneficiaries with diabetes (n = 169,613) were 1.7 times greater than those for those beneficiaries without diabetes (n = 968,832) in 1994. This ratio remained fairly constant over the 2 years of follow-up. Expenditures for beneficiaries with diabetes were highly skewed. However, few of these individuals remained in the highest expenditure quintile over the 2 years of follow-up. Using multiple regression analysis to adjust for demographic and clinical characteristics, we were able to explain 7% of the variation in total expenditures in 1995 and 6% of the variation in 1996. Using the same model, we were able to explain 10.7% of the variation in Part B expenditures in 1995 and 8% in 1996. CONCLUSIONS: Beneficiaries with diabetes are consistently more expensive than beneficiaries without diabetes. Demographic and clinical factors at baseline are able to predict only a small portion of future expenditures among this population, and the most expensive patients in one year were often not the most expensive in subsequent years. More work is necessary to assure equitable risk adjustment in the calculation of capitation rates for health plans and practitioners who specialize in the care of individuals with diabetes.

Clinical review 115: effect of thyroxine therapy on serum lipoproteins in patients with mild thyroid failure: a quantitative review of the literature.

The objective of our study was to estimate the expected change in serum lipoprotein concentrations after treatment with T4 in patients with mild thyroid failure (i.e. subclinical hypothyroidism). Our data sources included MEDLINE, between January 1966 and May 1999, and review of references from relevant articles. There were 1,786 published studies identified, 461 abstracts reviewed, 74 articles retrieved, 24 articles evaluated against predetermined entry criteria, and 13 studies systematically reviewed and abstracted. All studies reported serum total cholesterol concentration changes during T4 treatment, 12 reported triglyceride changes, 10 reported high-density lipoprotein (HDL) cholesterol changes, and 9 reported low-density lipoprotein (LDL) cholesterol changes. There were 247 patients in 13 studies. The mean decrease in the serum total cholesterol concentration was -0.20 mmol/L (-7.9 mg/ dL), with a 95% confidence interval of -0.09 to -0.34. The decline in serum total cholesterol was directly proportional to its baseline concentration. Studies enrolling hypothyroid participants receiving suboptimal T4 doses reported significantly larger decreases in serum total cholesterol after thyroid-stimulating hormone normalization than studies enrolling previously untreated individuals with mild thyroid failure [-0.44 mmol/L (-17 mg/dL) vs. -0.14 mmol/L (-5.6 mg/dL), P = 0.05]. The change in serum LDL cholesterol concentration was -0.26 mmol/L (-10 mg/dL), with a 95% confidence interval of -0.12 to -0.41. Serum HDL and triglyceride concentrations showed no change. These results, although based on fewer than 250 patients, suggest that T4 therapy in individuals with mild thyroid failure lowers mean serum total and LDL cholesterol concentrations. The reduction in serum total cholesterol may be larger in individuals with higher pretreatment cholesterol levels and in hypothyroid individuals taking suboptimal T4 doses. There do not seem to be significant effects of T4 on serum HDL or triglyceride concentrations.

Profile of a clinical practice: Thresholds for surgery and surgical outcomes for patients with primary hyperparathyroidism: a national survey of endocrine surgeons.

A 1991 NIH Consensus Development Conference statement provided recommendations for the management of patients with asymptomatic and minimally symptomatic primary hyperparathyroidism (primary HPT), but adherence to these guidelines has not been documented. We conducted a cross-sectional survey of North American members of the American Association of Endocrine Surgeons inquiring about surgeon and primary HPT patient characteristics, thresholds for surgery, and clinical outcomes. Multivariate regression was used to assess the relationship of physician characteristics to practice patterns and outcomes. Of 190 surgeons surveyed, 147 (77%) responded; 109 provided complete responses (57%). These surgeons spend 66% of their time in patient care and perform an average of 33 (range, 1-130) parathyroidectomies/yr. More than 72% of primary HPT patients who underwent surgery were asymptomatic or minimally symptomatic. High volume surgeons (>50 cases/yr) had significantly lower thresholds for surgery with respect to abnormalities in preoperative creatinine clearance, bone densitometry changes, and levels of intact PTH and urinary calcium compared to their low volume colleagues (1-15 cases/yr). Overall reported surgical cure rates were 95.2% after primary operation and 82.7% after reoperation. Compared to high volume surgeons, low volume endocrine surgeons had significantly higher complication rates after primary operation (1.9% vs. 1.0% respectively; P < 0.01) and reoperation (3.8% vs. 1.5%; P < 0.001) as well as higher in-hospital mortality rates (1.0% vs. 0.04%; P < 0.05). Endocrine surgeons operate on a large number of asymptomatic or minimally symptomatic primary HPT patients. Even among a group of highly experienced surgeons who typically see patients after referral from endocrinologists, clinical outcomes and criteria for surgery vary widely and appear to be associated with surgeon experience. Their criteria for surgery diverge from NIH guidelines. These results implore the endocrine community to examine the evidential basis for decisions made in the management of primary HPT.

U.S. nephrologists' attitudes towards renal transplantation: results from a national survey.

BACKGROUND: Renal transplantation is the optimal treatment for persons with end-stage renal disease (ESRD). A shortage of kidneys in the U.S. has focused increasing attention on the process by which kidneys are allocated. A national survey was undertaken to determine the relative importance of both clinical and nonclinical factors in the recommendation for renal transplantation by U.S. nephrologists. METHODS: We conducted a national random survey of 271 U.S. nephrologists using hypothetical patient scenarios to determine their recommendation for renal transplantation based on demographic, clinical, and social factors. Specifically, eight unique patient scenarios were randomly distributed to each survey respondent. RESULTS: According to responding nephrologists (response rate 53%), females were less likely than males to be recommended for renal transplantation [adjusted odds ratio (OR)=0.41; confidence interval (CI) 0.21, 0.79; for whites]. Asian males were less likely than white males to be recommended for transplantation (OR=0.46, CI 0.24, 0.91). Black-white differences in rates of recommendation were not found. Other factors associated with low rates of recommendation for renal transplantation included history of noncompliance (OR=0.17, CI 0.13, 0.23), <25% cardiac ejection fraction (OR=0.15, CI 0.10, 0.21), HIV infection (OR=0.01, CI 0.00, 0.01), and being >200 lbs (OR=0.73, CI 0.56, 0.95). CONCLUSIONS: Female gender, and Asian but not black race, were associated with a decreased likelihood that nephrologists would recommend renal transplantation for patients with end stage renal disease. The well-documented black-white disparities in use of renal transplantation may be due to unaccounted for factors or may arise at a subsequent step in the transplantation process.

Decision analysis in endocrinology and metabolism.

Decision analysis is a powerful tool for synthesizing and analyzing clinical decisions in the practice of endocrinology and metabolism. The technique involves defining strategies for comparison, choosing a time horizon, constructing a decision tree and model, selecting outcomes and assigning probabilities, taking into account the value of time, calculating the net clinical and cost outcomes, and performing sensitivity analysis. This technique and its utility for different populations and changing health care settings are illustrated for the decision of screening for mild thyroid failure with a thyroid-stimulating hormone assay at the periodic health examination. The strengths and limitations of decision analysis and future applications in endocrinology and metabolism are explored.

For-profit versus not-for-profit dialysis care for children with end stage renal disease.

OBJECTIVE: Over the last 2 decades, for-profit dialysis units have become the most common providers of renal replacement therapy for adults with end stage renal disease (ESRD) and have had an increasing role in the dialysis of children. We undertook a study to determine whether dialysis facility profit status influences the choice of dialysis therapy in the pediatric population. DESIGN: Cross-sectional study of national data from the Health Care Financing Administration. SETTING: Free-standing and hospital-based outpatient dialysis facilities in the United States. PATIENTS: A total of 1568 children and adolescents (

Capitation for cardiologists: accepting risk for coronary artery disease under managed care.

Patients with chronic disease may be excluded from capitated managed care plans due to higher than average expected costs. In an attempt to remedy this inequity, one type of risk adjustment technique proposes to set separate capitation rates for certain chronic illnesses, including coronary artery disease (CAD). Cardiologists, who increasingly are requested to accept capitation, will benefit from understanding the impact of using clinical factors as opposed to using demographic factors to set capitation rates. Using a 5% national random sample of the 1992 Medicare population, we determined mean annual expenditures and variation in expenditures of individuals with CAD. We compared the use of 2 demographic factors currently used for capitation rate adjustment (age and gender) with 2 factors not currently used--3-digit International Classification of Disease (ICD-9) code (a measure for severity) and Charlson index (a measure for comorbidity). Mean annual expenditures for individuals with CAD were more than double mean annual expenditures for the general Medicare population ($6,944 vs $3,247). Among individuals with CAD, mean expenditures of subgroups defined by both age and gender ranged from $6,205 to $7,724. In comparison, stratifying by measures of severity and comorbidity identified subgroups with lower and higher mean expenditures, producing a range of $1,702 to $19,959. Substantial variation of expenditures for individuals within subgroups defined by severity and comorbidity remained, with few patients having substantially higher expenditures than the rest. When capitation rates are set with the use of demographic factors alone, patients may be subjected to risk selection and physicians to financial loss. Using clinical measures may decrease the incentive for patient risk selection, but substantial financial risk to physicians would remain, because of a relatively few patients with high expenditures (or costs).

Reducing racial disparities in transplant activation: whom should we target?

Several studies have documented that blacks with end-stage renal disease (ESRD) are less likely than whites to be placed on the waiting list for a renal transplant. We examined trends in access over time to determine whether publication of these reports resulted in a reduction in disparity and identified those blacks who were most affected to focus future interventions. Three nationally representative groups of adult patients with ESRD (first dialysis in 1986 to 1987, 1990, or 1993) were followed up longitudinally to ascertain the date of first placement on the renal transplant waiting list. Cox proportional hazards models were used to characterize the magnitude of racial disparities in access to the waiting list with adjustment for clinical and sociodemographic factors. Lower rates of placement on the waiting list for blacks than whites persisted after adjustment for differences in both sociodemographic characteristics and health status (relative hazard [RH], 0.68; 95% confidence interval [CI], 0.59 to 0.79). The gap between blacks and whites did not narrow over time (blacks versus whites: 1986 to 1987 group, RH, 0.71; 95% CI, 0.59 to 0.86; 1990 group, RH, 0.69; 95% CI, 0.54 to 0.91; 1993 group, RH, 0.57; 0.43 to 0.77) and was greatest for the youngest and healthiest black patients, who were 50% and 40% less likely to be listed than corresponding whites, respectively. Interventions targeted toward young and healthy blacks, who are most likely to benefit from transplantation, are urgently needed to narrow black-white differences in transplant activation.

Relation between gender and vascular access complications in hemodialysis patients.

Native arteriovenous (AV) fistulae for hemodialysis vascular access are believed to be associated with fewer complications than synthetic polytetrafluoroethylene (PTFE) grafts. We conducted a study among patients in the Dialysis Morbidity and Mortality Study to compare risk factors for complications of AV fistulae and PTFE grafts in men and women and to examine the effect of age on vascular access complications. We analyzed data from 833 incident patients with end-stage renal disease who had a PTFE graft (n = 621) or AV fistula (n = 212) in use 1 month after starting hemodialysis therapy. Follow-up using inpatient and outpatient Medicare administrative data identified a 1.8-times greater risk for a subsequent vascular access procedure for PTFE grafts (0.71 procedures/access-year) than for AV fistulae (0.39 procedures/access-year). Men with grafts and women with grafts or fistulae had a greater risk for a first subsequent access procedure than did men with fistulae (0.79, 0.65, and 0.59 versus 0.33 procedures/access-year, respectively). After adjustment for age, race, presence of diabetes mellitus, and history of smoking, peripheral vascular disease, and cardiovascular disease, use of a PTFE graft compared with an AV fistula was associated with a greater risk for a first subsequent procedure in men (relative hazard, 2.2; 95% confidence interval [CI], 1.6 to 2.9), but not in women (relative hazard, 1.0; 95% CI, 0.7 to 1.4). The excess risk associated with a PTFE graft compared with an AV fistula was limited to men in the lower three quartiles of age (ie,

Septicemia in diabetic hemodialysis patients: comparison of incidence, risk factors, and mortality with nondiabetic hemodialysis patients.

Diabetes mellitus is the most common cause of treated end-stage renal disease (ESRD), and diabetic hemodialysis patients have a high mortality rate. To identify differences in risk of septicemia among diabetic and nondiabetic hemodialysis patients, we examined the incidence, risk factors, and mortality for septicemia in a large sample of the US hemodialysis population. We performed a longitudinal cohort study of the incidence and risk factors for hospitalized cases of septicemia in diabetic and nondiabetic hemodialysis patients using baseline data from the US Renal Data System case-mix severity study with 7-year follow-up from hospitalization and death records. Independent risk factors for septicemia were assessed using Poisson regression. Independent effect of septicemia on mortality was assessed using Cox proportional hazards analysis. Over 7 years, 11.1% of nondiabetic patients and 12.5% of diabetic patients experienced at least one episode of septicemia. Older age and low serum albumin were independent risk factors for septicemia in all patients. In diabetics, white race, peripheral vascular disease, and hemodialyzer reuse, particularly in type 1, were independent risk factors. In nondiabetics, coronary artery disease, cerebrovascular disease, and temporary and permanent catheters were associated with an increased risk. In both groups, patients who experienced an episode of septicemia had twice the risk of death from any cause and an eightfold risk of death from septicemia. Septicemia occurs equally frequently and carries a marked increased risk of death in both nondiabetic and diabetic hemodialysis patients. Improving nutritional status and minimizing the use of catheters might help ameliorate the risk of septicemia. In diabetics, aggressive treatment of peripheral vascular disease might help reduce the risk of septicemia. Further research to elucidate potential mechanisms for variations in risk for septicemia according to race and hemodialyzer reuse practices are warranted in diabetic patients.