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Biomedical subjects

David W Gjertson

Publications and source records attributed to David W Gjertson.

25 records · Page 2Linked to original sources
PubMed2003

Look-up survival tables for living-donor renal transplants: OPTN/UNOS data 1995-2002.

1. We have provided reference tables of living-donor kidney graft survival rates based on data reported to the OPTN/UNOS Registry between 1995-2002. Graft survival rates from 28,860 living-related (LRD) and 8,444 living-unrelated donor (LUD) kidneys were 6 and 4 percentage points higher, respectively, at one year after-transplantation compared to the rate for deceased donor kidneys (70,801 DD grafts with GS = 89%). Furthermore, living donor recipients enjoyed a 50% increased graft half-life (15 years for LRD and LUD vs. 10 years for DD). Significantly higher short- and long-term functional and patient survival rates were also observed in recipients of living donor kidneys (Fig. 1). 2. The effects of 15 cofactors on graft survival rates were similar across living donor types (Figs. 2-16). Living-donors always exhibited superior rates compared to DD transplants in comparable categories (Table 1). For example, Black recipients of LRD, LUD and DD kidneys demonstrated half lives of 10, 11 and 7 years, respectively, compared to 17, 16 and 11 years in their White counterparts. 3. Among LRD renal transplants, long (20+ year) half-lives were estimated in children (0-10 yrs) and recipients with inherited disease despite the presence of other detrimental factors. When combined with another factor known to promote long-term survival (few HLA mismatches, 0% PRA, no CMV, younger male donor), children's half-lives approached 30+ years. In contradistinction, LRD kidneys grafted into sensitized recipients (regrafted or high PRA) had poor outcomes except when donors were well HLA matched with their recipients. Recipients of older and CMV+ LRD kidneys also exhibited lower graft survival rates. 4. We confirmed the excellent outcomes of LUD renal transplants. Both spouse and other LUD transplants exhibited nearly indistinguishable results. Variations in recipient's pretransplant medical status, donor age and drug regimen tended to influence LUD outcomes more than LRD transplants, whereas HLA mismatches had less impact. This last result is expected since grafts matching a few HLA loci from unrelated individuals will not match (with high probability) remaining MHC loci.

Actuarial Analysis↗
PubMed2002

A pilot study of all-trans-retinoic acid for the treatment of human emphysema.

Emphysema results from progressive destruction of alveolar septae and was considered irreversible until all-trans-retinoic acid (ATRA) was shown to reverse anatomic and physiologic signs of emphysema in a rat model. To evaluate the feasibility of ATRA as a clinical therapy, 20 patients with severe emphysema were enrolled into a randomized, double-blind, placebo-controlled pilot study. Participants included 16 male and 4 female former smokers, two with alpha(1)-antitrypsin deficiency. Patients were treated with either 3 mo of ATRA (50 mg/m(2)/d) or 3 mo of placebo, followed by a 3-mo crossover phase. Plasma drug levels were followed and outcome measures included serial pulmonary function tests, blood gases, lung compliance, computed tomography (CT) imaging, and quality of life questionnaires. In general, treatment was well tolerated and associated with only mild side effects including skin changes, transient headache, hyperlipidemia, transaminites, and musculoskeletal pains. Plasma drug levels varied considerably between subjects and decreased significantly over time in 35% of the participants. Physiologic and CT measurements did not change appreciably in response to therapy. We conclude that ATRA is well tolerated in patients with emphysema, and trials evaluating higher doses, longer treatment, or different dosing schedules are feasible.

Aged↗
PubMed2002

Four causes of cadaveric kidney transplant failure: a competing risk analysis.

Multiple pathological processes are responsible for renal transplant loss. Development of effective prophylactic regimens requires that risks associated with different outcomes be assessed when several processes act together. A multistate competing risk model that derived multiple endpoint probabilities without averaging impacts of covariates over different outcomes or overestimating fractions of survivors was used to estimate the influence of 16 factors simultaneously on four failure types (acute rejection, chronic rejection, death with a functioning graft and all other causes combined). We analyzed 12,413 non-Black and 5,121 Black patients undergoing primary cadaveric kidney transplantation reported to UNOS during 1994-96. Black recipients generally demonstrated higher rates of failure, but the method provided joint probabilities for each failure type and covariate level. To illustrate, a middle-aged Black recipient had probabilities of 6.5%, 5.9%, 2.6% and 6.6% to experience acute rejection failure, chronic rejection failure, death with a functioning graft and other failures, respectively, within 3 years. The corresponding non-Black's chances were 2.9%, 2.5%, 2.7% and 3.6%. The overall 3-year survival equaled 78.4% [100%-(6.5% + 5.9% + 2.6% + 6.6%)] and 88.3% for Blacks and non-Blacks, respectively. The growing complexity of transplantation will benefit from new analytic approaches that accommodate multiple transitions along diverse paths to eventual graft loss or death.

Adult↗
PubMed2002

Calcium begets calcium: progression of coronary artery calcification in asymptomatic subjects.

PURPOSE: To test the hypothesis that the rate of coronary artery calcium progression is sex specific, namely, that it is greater in men than in women, and that it is age related, particularly in women. MATERIALS AND METHODS: This was a retrospective study of the progression of coronary artery calcium in 217 consecutive asymptomatic subjects who underwent at least two electron-beam computed tomographic studies of the heart. Calcium in the distribution of the epicardial arteries was quantified by using both the conventional coronary artery calcium score (CCS) and the calcium volume score (CVS). Linear regression models were used to judge the joint influence of various risk factors, including sex and age, on rates of coronary artery calcium progression. RESULTS: This study included 103 women and 114 men. The mean interval between the subjects' first and last studies was 25 months +/- 11 (SD). Regression analyses clearly demonstrated that the amount of coronary artery calcium present at the initial study was the most important determinant of calcium progression. This was true when coronary artery calcium was quantified by using the conventional CCS (P <.001) or CVS (P <.001). Neither sex nor age was a significant predictor of coronary artery calcium progression. Among traditional risk factors, only hypertension (P =.02) and diabetes (P =.01) were significant independent factors for calcium progression. CONCLUSION: In asymptomatic subjects, the initial CCS and CVS were the most important factors that affected rate of coronary artery calcium progression. Neither age nor sex was as important as these factors in determination of coronary artery calcium progression.

Adult↗
PubMed2002

A multi-factor analysis of kidney regraft outcomes.

1. GENERAL: We updated prior analyses of renal retransplants reported to the UNOS Registry by estimating the compound effects of 22 covariates on regraft survival within 2 consecutive posttransplant risk periods. During an early risk period, 9,126 kidney-only regraft recipients were followed through one year, and, in a second risk period, 7,798 recipients whose regrafts survived beyond one year were followed for 5 years posttransplant. The study sample represented a unique set of patients whose first renal transplants were also recorded by the registry. 2. RELATIVE INFLUENCE OF TRANSPLANT FACTORS AND CENTER: From a multivariate log-linear analysis, the top 5 factors influencing one-year regraft survival rates were ranked as follows: 1) transplant center (accounted for 24% of the variation in short-term outcomes); 2) duration of first graft (19%); 3) donor age (15%); 4) recipient's body mass index (7%); and 5) year of transplant (6%). Ranking long-term outcomes demonstrated that donor age was the dominant factor governing the 5-year survival rates among regrafts, accounting for 30% of long-term variation. Transplant center, recipient age and race, and donor relationship accounted for another 16%, 14%, 10% and 8% of changes in long-term regraft survival, respectively. Despite center effects, a center's volume did not appear to be associated with outcome, and a center's short-term effect did not predict its long-term results, as the correlation between one- and 5-year center-specific rates was small (R = 0.11) and statistically insignificant (P = 0.15). 3. RECIPIENT FACTORS RELATED TO FIRST TRANSPLANT: Among 4 recipient factors related to a first transplant, only the first graft's survival duration significantly influenced both short- and long-term outcomes of regrafts. If the first graft survived for more than 2 years, a regraft had an approximate 90% chance of surviving to one year as compared with an 80% chance if the first graft failed within 2 years. Regrafts among recipients whose first graft lasted more than 4 3/4 years exhibited better 5-year survival rates (82.2%) versus the less-than-average rates for the other groups. 4. RECIPIENT FACTORS: Six of the 7 recipient factors selected for analysis significantly influenced short- or long-term regraft outcomes: 1) female recipients had significantly higher long-term regraft survival rates; 2) Black recipients of regrafts had poor long-term results; 3) children (0-12 yr) exhibited markedly diminished one-year regraft survival rates, and teenage recipients exhibited poor long-term regraft function; 4) obese recipients (body mass index > 30 kg/m2) had poor one-year and 5-year regraft survival rates; 5) impaired functional status immediately pre-retransplant significantly reduced both short- and long-term rates; and 6) regraft recipients whose PRA was above 0% exhibited diminished one-year and 5-year regraft survival rates. 5. DONOR FACTORS: Regraft recipients receiving a living donor's kidney had 87% one-year graft survival, outperforming cadaveric regrafts by 8 percentage points during the initial period. At 5 years, survival rates for patients receiving living related (except parents) or unrelated donor regrafts enjoyed above average 5-year survival rates, but parental and cadaver types of donors demonstrated poor long-term values. The strong short-term effect of donor age emanated from poorer regraft functions from both younger and older donors, whereas the long-term effect arose primarily as a result of the poor regraft functions from older donors. After 24 hours of cold ischemia time, early cadaveric regraft survival rates were significantly impaired. 6. TRANSPLANT FACTORS: This study clarified the effects of HLA mismatches and re-exposure to mismatched antigens on regraft survival rates. Generally, receiving a zero mismatched regraft was beneficial. Specifically, class I incompatible regrafts with repeat AB mismatches demonstrated superior long-term rates, even surpassing the 5-year results for 0 AB mismatches. Incompatible class II regrafts with re-exposure to DR antigens had marginal reductions in short- and long-term outcomes. Increasing numbers of HLA-AB mismatches did not seriously impact regraft survival, but any DR mismatch seriously reduced the one-year regraft survival rate.

Adolescent↗
PubMed2002

Maintenance immunosuppressive treatment and graft half-life.

Longer graft half-lives were associated with Caucasian race, living donors, younger donor age. The HLA-matching effect on graft half-life was only significant when comparing HLA-matched transplant recipients with recipients of HLA-mismatched transplants, but not significant between mismatched recipients with varying degrees of HLA mismatch. First transplant recipients maintained on newer post-1995 immunosuppressive drug therapies, including tacrolimus, MMF and steroids, Neoral, MMF and steroids or Neoral, azathioprine and steroids, always had longer graft half-lives than patients on pre-1995 CsA protocols. The difference in graft half-lives between new and old protocols reached statistical significance in some categories. Patients on triple therapies had consistently longer graft half-lives than those receiving double therapies.

Adrenal Cortex Hormones↗