Characteristics of Rural and Urban Cadaveric Organ Transplant Donors and Recipients

CONTEXT

Health disparities have been found when comparing rural and urban populations.

PURPOSE

To compare characteristics of rural and urban cadaveric transplant donors and recipients.

METHODS

We used deidentified individual-level data on 55,929 cadaveric transplant donor-recipient exchanges between 2000 and 2003 and examined the relative rates of donating and receiving cadaveric transplants for rural compared to urban residents, as defined by ZIP Codes.

FINDINGS

When compared to their urban counterparts, rural organ donors were more likely to have died from head trauma, drowning, motor vehicle accidents, or suicide and less likely to have died from cerebrovascular events, cardiac events, or homicide (P < .001 for all). Rural transplant recipients had lower levels of educational attainment and were less likely to have had the transplant financed by private insurance (P < .001 for all). While we found no statistical difference in days wait to organ transplantation, rural residents were more likely to donate than to receive cadaveric organs (P < .001).

CONCLUSIONS

The differences in organ donation that we found warrant further exploration.

An organizational ethics decision-making process

The management team of Memorial Medical Center must make a decision regarding the continuation of one of its outpatient clinics. To provide better community service, MMC developed three outpatient clinics throughout a large metropolitan area. Over the past several years, one of the clinics has consistently been a financial loser. The losses have grown even as the costs of maintaining the clinic have increased. A primary reason for the negative financial performance is the high amount of nonreimbursed healthcare services-the clinic provides needed healthcare to a low-income part of the metropolitan area. Several members of the executive management team believe MMC has no alternative other than closing the clinic. One member of the management team, however, believes that the situation raises ethical concerns, and that executive seeks an ethics-grounded response to the problem.

Ten Myths About Decision-Making Capacity

As a matter of practical reality, what role patients will play in decisions about their health care is determined by whether their clinicians judge them to have decision-making capacity. Because so much hinges on assessments of capacity, clinicians who work with patients have an ethical obligation to understand this concept. This article, based on a report prepared by the National Ethics Committee (NEC) of the Veterans Health Administration (VHA), seeks to provide clinicians with practical information about decision-making capacity and how it is assessed. A study of clinicians and ethics committee chairs carried out under the auspices of the NEC identified the following 10 common myths clinicians hold about decision-making capacity: (1) decision-making capacity and competency are the same; (2) lack of decision-making capacity can be presumed when patients go against medical advice; (3) there is no need to assess decision-making capacity unless patients go against medical advice; (4) decision-making capacity is an "all or nothing" phenomenon; (5) cognitive impairment equals lack of decision-making capacity; (6) lack of decision-making capacity is a permanent condition; (7) patients who have not been given relevant and consistent information about their treatment lack decision-making capacity; (8) all patients with certain psychiatric disorders lack decision-making capacity; (9) patients who are involuntarily committed lack decision-making capacity; and (10) only mental health experts can assess decision-making capacity. By describing and debunking these common misconceptions, this article attempts to prevent potential errors in the clinical assessment of decision-making capacity, thereby supporting patients' right to make choices about their own health care.

Stage-structured cycles promote genetic diversity in a predator–prey system of Daphnia and algae

Competition theory predicts that population fluctuations can promote genetic diversity when combined with density-dependent selection. However, this stabilizing mechanism has rarely been tested, and was recently rejected as an explanation for maintaining diversity in natural populations of the freshwater herbivore Daphnia pulex. The primary limitation of competition theory is its failure to account for the alternative types of population cycles that are caused by size- or stage-dependent population vital rates--even though such structure both explains the fluctuating dynamics of many species and may alter the outcome of competition. Here we provide the first experimental test of whether alternative types of cycles affect natural selection in predator-prey systems. Using competing Daphnia genotypes, we show that internally generated, stage-structured cycles substantially reduce the magnitude of selection (thereby contributing to the maintenance of genetic diversity), whereas externally forced cycles show rapid competitive exclusion. The change in selection is ecologically significant, spanning the observed range in natural populations. We argue that structured cycles reduce selection through a combination of stalled juvenile development and stage-specific mortality. This potentially general fitness-equalizing mechanism may reduce the need for strong stabilizing mechanisms to explain the maintenance of genetic diversity in natural systems.

Ten myths about decision-making capacity

As a matter of practical reality, what role patients will play in decisions about their health care is determined by whether their clinicians judge them to have decision-making capacity. Because so much hinges on assessments of capacity, clinicians who work with patients have an ethical obligation to understand this concept. This article, based on a report prepared by the National Ethics Committee (NEC) of the Veterans Health Administration (VHA), seeks to provide clinicians with practical information about decision-making capacity and how it is assessed. A study of clinicians and ethics committee chairs carried out under the auspices of the NEC identified the following 10 common myths clinicians hold about decision-making capacity: (1) decision-making capacity and competency are the same; (2) lack of decision-making capacity can be presumed when patients go against medical advice; (3) there is no need to assess decision-making capacity unless patients go against medical advice; (4) decision-making capacity is an "all or nothing" phenomenon; (5) cognitive impairment equals lack of decision-making capacity; (6) lack of decision-making capacity is a permanent condition; (7) patients who have not been given relevant and consistent information about their treatment lack decision-making capacity; (8) all patients with certain psychiatric disorders lack decision-making capacity; (9) patients who are involuntarily committed lack decision-making capacity; and (10) only mental health experts can assess decision-making capacity. By describing and debunking these common misconceptions, this article attempts to prevent potential errors in the clinical assessment of decision-making capacity, thereby supporting patients' right to make choices about their own health care.

Phylogeny of the Bangia flora of New Zealand suggests a southern origin for Porphyra and Bangia (Bangiales, Rhodophyta)

Analysis of nuclear small subunit ribosomal RNA gene (18S rDNA) sequence data from 123 samples of the red algal genus Bangia from mainland New Zealand has revealed diversity exceeding that reported for the genus from any other region in the world. Our study resolves two New Zealand Bangia taxa basal to the order Bangiales, and five clades of Bangia, four of which include New Zealand members. The basal taxa are separated from each other by 139 bp and differ from all other Bangia taxa in the New Zealand region by 103-163 bp over approximately 1750 bp 18S rDNA sequence data. Our results reveal a Bangia flora of previously unsuspected richness, and show that the simple morphology of these organisms obscures significant levels of genetic diversity. The presence of high diversity and retention of basal taxa in New Zealand Bangia raises the prospect that the southern hemisphere, and particularly eastern Gondwana, is not only a centre of diversity, but a centre of origin for the modern Bangiales.

Multiple dynamics in a single predator-prey system: experimental effects of food quality

Recent work with the freshwater zooplankton Daphnia has suggested that the quality of its algal prey can have a significant effect on its demographic rates and life-history patterns. Predator-prey theory linking food quantity and food quality predicts that a single system should be able to display two distinct patterns of population dynamics. One pattern is predicted to have high herbivore and low algal biomass dynamics (high HBD), whereas the other is predicted to have low herbivore and high algal biomass dynamics (low HBD). Despite these predictions and the stoichiometric evidence that many phytoplankton communities may have poor access to food of quality, there have been few tests of whether a dynamic predator-prey system can display both of these distinct patterns. Here we report, to the authors' knowledge, the first evidence for two dynamical patterns, as predicted by theory, in a single predator-prey system. We show that the high HBD is a result of food quantity effects and that the low HBD is a result of food quality effects, which are maintained by phosphorus limitation in the predator. These results provide an important link between the known effects of nutrient limitation in herbivores and the significance of prey quality in predator-prey population dynamics in natural zooplankton communities.