Biomedical subjects

Dave Collett

Publications and source records attributed to Dave Collett.

3 recordsLinked to original sources

PubMed2006

Long-term graft outcome with mycophenolate mofetil and azathioprine: A paired kidney analysis.

BACKGROUND: Randomized controlled trials and U.S. Registry data have demonstrated that mycophenolate mofetil (MMF) reduces acute rejection rates and improves graft survival. We undertook the first paired kidney analysis comparing the effects of MMF and azathioprine on graft outcome in the United Kingdom. METHODS: In all, 238 deceased donors from 1999 to 2002 who donated one kidney to a patient treated with MMF and the other kidney to a patient treated with azathioprine were identified from the national transplant database held by U.K. Transplant. Graft function and rates of change of graft function were compared using multiple linear regression analyses adjusting for covariates on an intention-to-treat basis. Incidence of acute rejection and delayed graft function were studied using logistic regression. Patient and graft survival censored for death were evaluated with Cox regression analyses. RESULTS: The MMF-treated patients exhibited a nonsignificant trend towards improved graft function but with increased rejection rates (44% versus 31%, P < 0.01). Treatment with MMF did not reduce delayed graft function rates. Univariate analysis showed that graft survival was inferior in MMF-treated patients (90% versus 95%, log-rank, P = 0.02) but in multivariate Cox regression models, MMF treatment was not a significant factor. Surprisingly, in the first year 32% of patients achieved daily doses of less than 2 g of MMF compared to 18% of patients who received less than 100 mg of azathioprine (P < 0.01). CONCLUSION: In this real-life study, there was no difference in patient or graft outcome between MMF and azathioprine treated groups despite increased rejection rates in patients receiving MMF therapy.

Azathioprine↗

PubMed2006

Potential for organ donation in the United Kingdom: audit of intensive care records.

OBJECTIVES: To determine the true potential for solid organ donation from deceased heartbeating donors and the reasons for non-donation from potential donors. DESIGN: An audit of all deaths in intensive care units, 1 April 2003 to 31 March 2005. The study was hierarchic, in that information was sought on whether or not brain stem testing was carried out; if so, whether or not organ donation was considered; if so whether or not the next of kin were approached; if so, whether or not consent was given; if so, whether or not organ donation took place. SETTING: 341 intensive care units in 284 hospitals in the United Kingdom. PARTICIPANTS: 46,801 dead patients, leading to 2740 potential heartbeating solid organ donors and 1244 actual donors. MAIN OUTCOME MEASURES: Proportion of potential deceased heartbeating donors considered for organ donation, proportion of families who denied consent, and proportion of potential donors who became organ donors. RESULTS: Over the two years of the study, 41% of the families of potential donors denied consent. The refusal rate for families of potential donors from ethnic minorities was twice that for white potential donors, but the age and sex of the potential donor did not affect the refusal rate. In 15% of families of potential donors there was no record of the next of kin being approached for permission for organ donation. CONCLUSIONS: Intensive care units are extremely good in considering possible organ donation from suitable patients. The biggest obstacle to improving the organ donation rate is the high proportion of relatives who deny consent.

Attitude to Health↗

PubMed2004

Parametric accelerated failure time models with random effects and an application to kidney transplant survival.

Accelerated failure time models with a shared random component are described, and are used to evaluate the effect of explanatory factors and different transplant centres on survival times following kidney transplantation. Different combinations of the distribution of the random effects and baseline hazard function are considered and the fit of such models to the transplant data is critically assessed. A mixture model that combines short- and long-term components of a hazard function is then developed, which provides a more flexible model for the hazard function. The model can incorporate different explanatory variables and random effects in each component. The model is straightforward to fit using standard statistical software, and is shown to be a good fit to the transplant data.

Adult↗