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David T Gilbertson

Publications and source records attributed to David T Gilbertson.

26 records · Page 2Linked to original sources

Differences in diabetes prevalence, incidence, and mortality among the elderly of four racial/ethnic groups: whites, blacks, hispanics, and asians.

OBJECTIVE: To examine diabetes prevalence, incidence, and mortality from 1993 to 2001 among fee-for-service Medicare beneficiaries > or = 67 years of age. RESEARCH DESIGN AND METHODS: This study was a retrospective analysis of a 5% random sample of Medicare fee-for-service beneficiaries > or = 65 years of age in each year. RESULTS: In 1993, the prevalence of diabetes among those > or = 67 years of age was 145 cases per 1,000 individuals. By 2001, it was 197/1,000, an increase of 36.0%. The 2001 prevalence among Hispanics (334/1,000) was significantly higher than among blacks (296/1,000), Asians (243/1,000), and whites (184/1,000, P < 0.0001). During the 7-year period the greatest increase in diabetes prevalence was among Asians (68.0%). Between 1994 and 2001, the annual rate of newly diagnosed elderly individuals with diabetes increased by 36.9%. Hispanics had the greatest increase at 55.0%. The mortality rate among individuals with diabetes decreased by approximately 5% between 1994 and 2001 from 92.1/1,000 to 87.2/1,000 (P < 0.001), due to a 6% decrease among whites. No decrease in mortality was seen among elderly individuals without diabetes, it was 55/1,000 in 1994 and 54/1,000 in 2001. CONCLUSIONS: The dramatic increase in the incidence and prevalence of diabetes likely reflect a combination of true increases, as well as changes in the diagnostic criteria and increased interest in diagnosing and appropriately treating diabetes in the elderly. Improved treatment may have had an impact on mortality rates among individuals with diabetes, although they could have been influenced by the duration of diabetes before diagnosis, which has likely decreased. Changes in incidence, prevalence, and mortality in elderly individuals with diabetes need to continue to be monitored.

Age Distribution↗

Does cadaveric donor renal transplantation ever provide better outcomes than live-donor renal transplantation?

BACKGROUND: Live donor renal transplantation (LRT) now comprises more than 40% of all kidney transplants performed in the United States. Many patients on the cadaveric waiting list have a prospective live kidney donor. This study determines whether cadaveric donor renal transplantation (CRT) can demonstrate better outcomes than LRT. METHODS: From the United States Renal Data System registry, 31,909 adult recipients of a first-time kidney transplant from 1995 to 1998 were analyzed. Recipients were followed until December 31, 2000. RESULTS: CRT, more human leukocyte antigen (HLA) mismatches, increased donor age, cold ischemia time greater than 24 hr, African American recipient, and a history of diabetic nephropathy all increased the risk of graft failure, return to dialysis, and death. Nevertheless, in specific circumstances, CRT could provide better outcomes than LRT. For example, in recipients aged 18 to 59 years with a hypothetical live kidney donor aged 50 years and four HLA mismatches, the relative risk of graft loss with LRT is comparable or increased compared with CRT if the cadaveric kidney donor is much younger or with fewer HLA mismatches. On the other hand, for recipients aged 60 years or older, CRT never provides better outcomes than LRT. All analyses were adjusted for recipient race, gender, and history of diabetic nephropathy. There were no significant interactions among donor type, HLA mismatches, donor age, and cold ischemia time. CONCLUSIONS: The elderly recipient with an imminent LRT should never be offered CRT. A combination of recipient and donor factors can make CRT preferable to LRT in younger patients.

Adolescent↗

Clinical factors associated with achieving K/DOQI hemoglobin targets in hemodialysis patients.

BACKGROUND: Few studies have assessed treatable factors associated with achieving the Kidney Disease Outcomes Quality Initiative (K/DOQI) guideline of hemoglobin values of 11 to 12 g/dL in anemic hemodialysis patients. METHODS: This was a retrospective study of 30,029 prevalent hemodialysis patients with mean hemoglobin values less than 11 g/dL between January 1 and March 31, 1999. We studied the associations between demographic characteristics, comorbid conditions, disease severity, urea reduction ratio, epoetin doses, intravenous iron doses, and mean hemoglobin values in the ensuing 3 months. RESULTS: Approximately half (51.3%) of patients reached a mean hemoglobin value of at least 11 g/dL. By multiple logistic regression, the major factors showing a positive association with this outcome included a urea reduction ratio greater than 75% (odds ratio [OR], 1.23; P < 0.0001) and intravenous iron (OR: for 0 vials/month, 1; for < 1, 1.22; for 1 to 1.9, 1.36; 2 to 2.9, 1.48; for 3 to 3.9, 1.61; for > or = 4, 1.79; P < 0.0001), while a negative association with hemoglobin response, possibly representing epoetin resistance, was shown for initial severity of anemia (OR: for initial hemoglobin value < 7 g/dL, 0.06; for 7 to 7.9 g/dL, 0.12; for 8 to 8.9 g/dL, 0.23; for 9 to 9.9 g/dL, 0.45; for 10 to 10.9 g/dL, 1; P < 0.0001) and epoetin doses in the highest quintile (OR for > 38,000 units/wk, 0.76; P < 0.0001). CONCLUSION: In patients with persistently low hemoglobin values, optimizing urea clearance and a proactive approach to intravenous iron therapy may enhance epoetin responsiveness.

Adult↗

Body size and outcomes on peritoneal dialysis in the United States.

BACKGROUND: Being overweight is often cited as a relative contraindication to peritoneal dialysis. Our primary objective was to determine whether actual mortality rates support this opinion. METHODS: Retrospective cohort study of United States Medicare patients initiating dialysis between 1995 and 2000 (N = 418,021; 11% peritoneal dialysis). RESULTS: Seven percent were underweight [body mass index (BMI) < 18.5 kg/m2], 27% were overweight (BMI 25.0 to 29.9 kg/m2), and 23% were obese (BMI> 29.9 kg/m2) at dialysis initiation. Compared to those with normal BMI, the adjusted odds of initiating peritoneal dialysis were 0.70 (P < 0.05) in underweight, 1.12 (P < 0.05) in overweight, and 0.87 (P < 0.05) in obese subjects. Among peritoneal dialysis patients, adjusted mortality hazard ratios in the first, second, and third year were 1.45 (P < 0.05), 1.28 (P < 0.05), and 1.17 for the underweight, respectively; 0.84 (P < 0.05), 0.89 (P < 0.05), and 0.98 for the overweight, respectively; and 0.89 (P < 0.05), 0.99, and 1.00 for the obese, respectively. Apart from higher third-year mortality in the obese, associations were similar after censoring at a switch to hemodialysis. For transplantation, the corresponding results were 0.76 (P < 0.05), 0.90 (P < 0.05), and 0.88 for the underweight, respectively; 0.95, 1.06, and 0.93 for the overweight, respectively; and 0.62 (P < 0.05), 0.68, and 0.71 for the obese, respectively. For switching to hemodialysis, hazards ratios were 0.92, 0.97, and 0.80 for the underweight, respectively; 1.07, 1.11 (P < 0.05), and 1.03 for the overweight, respectively; and 1.28 (P < 0.05), 1.29 (P < 0.05), and 1.36 (P < 0.05) for the obese, respectively. CONCLUSION: Although less likely to initiate peritoneal dialysis, overweight and obese peritoneal dialysis patients have longer survival than those with lower BMI, not adequately explained by lower transplantation and technique survival rates.

Adolescent↗

Influenza vaccine delivery and effectiveness in end-stage renal disease.

BACKGROUND: Influenza vaccination rates in the general population have been associated with improved outcomes, yet high-risk populations, such as end-stage renal disease (ESRD) patients, have received little attention in determining the potential benefits. This report assessed the frequency and effectiveness of influenza vaccination, while also assessing disparities in vaccination rates in the ESRD population. METHODS: Using the United States Renal Data System research files containing claims for all Medicare ESRD patients, vaccination rates and outcomes among vaccinated and unvaccinated persons for the 1997 to 1998 and 1998 to 1999 influenza seasons were compared after adjustment for baseline demographic factors and health characteristics. RESULTS: Vaccination rates in the ESRD population were less than 50% for each season. Influenza vaccination rates were lower in non-whites, women, younger patients, and peritoneal dialysis patients. Influenza vaccination was associated with a lower risk for hospitalization and death. CONCLUSIONS: Despite universal coverage of free influenza vaccination, the ESRD population had a less than 50% vaccination rate for the years 1997 to 1998 and 1998 to 1999 as demonstrated by Medicare billing data. Substantial differences were found in vaccination rates among non-whites and peritoneal dialysis patients. This study confirms that the ESRD populations benefit from influenza vaccination, suggesting that dialysis providers should take advantage of all opportunities to immunize this high-risk group.

Adult↗

Chronic kidney disease and cardiovascular disease in the Medicare population.

BACKGROUND: The extent of diabetes, chronic kidney disease (CKD), and cardiovascular disease (CVD) in the Medicare population is relatively unknown. Also unknown is the effect of these diseases on patient survival before end-stage renal disease (ESRD). METHODS: Prevalent cohorts of Medicare enrollees from 1996 to 2000 were assessed for diabetes and CKD, presence of CVD, and probability of death versus ESRD in the follow-up period. Hospitalization rates and, in diabetics, lipid testing and glycemic control monitoring were also assessed. RESULTS: The prevalence of diabetes in the Medicare population increased at 4.4% per year, reaching 18.9% in the 1999-2000 cohort. Approximately 726,000 elderly Medicare enrollees carry a diagnosis code for CKD. Those with CKD are 5 to 10 times more likely to die before reaching ESRD than the non-CKD group. In CKD patients, CVD is twice as common and advances at twice the rate. Cardiovascular disease advances at a similarly higher rate in CKD patients who die and those who survive to ESRD. Heart failure hospitalizations are 5 times greater in CKD patients and only 30% less than those in dialysis patients. Only half of the CKD patients with diabetes who advance to ESRD had a lipid or glycosylated hemoglobin test done in the year before or after dialysis initiation. CONCLUSION: Diabetes, the leading cause of ESRD, is increasing in the general Medicare population at 4.4% per year. Cardiovascular disease is common, progresses at twice the rate, is associated with death before ESRD, and patients receive suboptimal risk factor monitoring. Active identification and treatment of CKD patients is needed.

Heart Failure↗

A comparison of transplant outcomes in peritoneal and hemodialysis patients.

BACKGROUND: Studies examining the effect of pre-transplant dialysis modality on graft and patient survival after kidney transplantation have produced conflicting results. Therefore, we studied the effects of pre-transplant dialysis modality on outcomes in a large United States cohort. METHODS: We compared rates of transplantation between peritoneal dialysis and hemodialysis patients from the years 1995 to 1998 in the United States (N = 252,402) and outcomes after transplantation (N = 22,776), using data from the Centers for Medicare and Medicaid Services. RESULTS: In a Cox proportional hazards analysis that was adjusted for multiple patient characteristics, kidney transplantation was 1.39 (95% CI = 1.35 to 1.43) times more likely in peritoneal dialysis vs. hemodialysis patients (P < 0.0001). Over the entire follow-up period, the adjusted risk for death-censored graft failure was 1.15 (1.04 to 1.26) times higher in peritoneal dialysis vs. hemodialysis (P < 0.05), but mortality and overall graft failure rates were not different. Pre-transplant dialysis modality did not affect outcomes for patients who survived with a functioning kidney for at least 3 months. However, in adjusted Cox analyses restricted to the first 3 months, peritoneal dialysis was associated with a 1.23 (1.09 to 1.39) times higher risk for early graft failure (P < 0.001) and a 1.33 (1.16 to 1.53) times higher risk for death-censored graft failure (P < 0.001). Peritoneal dialysis patients, however, were seen to have a lower incidence of delayed graft function. In a smaller sample of patients with data on causes of early graft failure, graft thrombosis was more commonly listed as a cause of graft failure among peritoneal dialysis patients, 41% (64/156), compared to hemodialysis patients, 30% (106/349), P < 0.05. CONCLUSIONS: Kidney transplantation is more frequent in peritoneal dialysis than in hemodialysis patients, and transplantation in peritoneal dialysis patients is more frequently associated with early, but not late, graft failure. Delayed graft function was less common in peritoneal dialysis patients but this potential benefit appears to be offset by other factors which are associated with early graft loss. Additional studies are needed to determine what factors may help understand this early risk of graft failure.

Adolescent↗

Anemia and cost in Medicare patients with congestive heart failure.

The objective of this study was to examine the total cost to Medicare associated with the presence of anemia in congestive heart failure (CHF) patients. International Classification of Diseases, Ninth Revision, Clinical Modification codes were used to identify anemia, CHF, and comorbid conditions in 2002, and total Medicare costs were calculated for 2003. The mean patient age was 77.8 years. Anemia, present in 32% of CHF patients, was associated with older age, female sex, non-white race, and increasing burden of comorbidity. The total per-member-per-month cost in 2003 was $1781.01 among CHF patients with anemia in the preceding year compared with $1142.38 for CHF patients without anemia, a ratio of 1.56 (95% confidence interval, 1.5589-1.5592). When adjustment was made for baseline demographic factors and comorbid conditions, the corresponding ratio was 1.25 (95% confidence interval, 1.2546-1.2548). Anemia, a common association of CHF in elderly patients, is an antecedent association of increased societal medical expenditure.

Aged↗