Variation in cadaveric organ donor rates in the UK

Considerable variation exists in the organ donation rate between kidney retrieval areas (KRAs) within the UK. The causes for this are unknown. This study examines whether or not observed variations are correlated with various possible explanatory factors.

A geographical study involving Poisson regression analysis was carried out of all 21 KRAs in the UK in 1999 and 2000, with donor rate as dependent variable, and the following independent variables: road traffic accident, intracerebral haemorrhage and other trauma death rates; intensive care unit (ICU) bed numbers; co-location of transplant and neurosurgical units; population ethnicity; proportion of the population on the organ donor register; transplant coordinator numbers; and transplant unit numbers. Main outcome measures were: donor rate in each KRA; strength of association between independent and dependent variables; and magnitude of changes in the donor rate associated with changes in independent variables.

The donor rate varied between eight and 27.4 donors per million population per year. There was an association between donor rate and general ICU bed numbers (more beds associated with a higher donor rate), but this was of borderline statistical significance (P = 0.065). However, the donor rate was negatively associated (P = 0.02) with neurosurgical ICU bed numbers (more beds, fewer donors) and the proportion of the population from minority ethnic communities. There was no statistically significant association with the other independent variables.

There is significant variation in the organ donor rate between different parts of the UK. More research is needed to explore the counter-intuitive association between neurosurgical ICU beds and donations, and to determine the remaining causes of the observed variation.