Shifting paradigms in eligibility criteria for live kidney donation: a systematic review

Comparing the coverage, recall, and precision of searches for 120 systematic reviews in Embase, MEDLINE, and Google Scholar: a prospective study

BACKGROUND

Previously, we reported on the low recall of Google Scholar (GS) for systematic review (SR) searching. Here, we test our conclusions further in a prospective study by comparing the coverage, recall, and precision of SR search strategies previously performed in Embase, MEDLINE, and GS.

METHODS

The original search results from Embase and MEDLINE and the first 1000 results of GS for librarian-mediated SR searches were recorded. Once the inclusion-exclusion process for the resulting SR was complete, search results from all three databases were screened for the SR's included references. All three databases were then searched post hoc for included references not found in the original search results.

RESULTS

We checked 4795 included references from 120 SRs against the original search results. Coverage of GS was high (97.2 %) but marginally lower than Embase and MEDLINE combined (97.5 %). MEDLINE on its own achieved 92.3 % coverage. Total recall of Embase/MEDLINE combined was 81.6 % for all included references, compared to GS at 72.8 % and MEDLINE alone at 72.6 %. However, only 46.4 % of the included references were among the downloadable first 1000 references in GS. When examining data for each SR, the traditional databases' recall was better than GS, even when taking into account included references listed beyond the first 1000 search results. Finally, precision of the first 1000 references of GS is comparable to searches in Embase and MEDLINE combined.

CONCLUSIONS

Although overall coverage and recall of GS are high for many searches, the database does not achieve full coverage as some researchers found in previous research. Further, being able to view only the first 1000 records in GS severely reduces its recall percentages. If GS would enable the browsing of records beyond the first 1000, its recall would increase but not sufficiently to be used alone in SR searching. Time needed to screen results would also increase considerably. These results support our assertion that neither GS nor one of the other databases investigated, is on its own, an acceptable database to support systematic review searching.

Kidney-Failure Risk Projection for the Living Kidney-Donor Candidate

BACKGROUND

Evaluation of candidates to serve as living kidney donors relies on screening for individual risk factors for end-stage renal disease (ESRD). To support an empirical approach to donor selection, we developed a tool that simultaneously incorporates multiple health characteristics to estimate a person's probable long-term risk of ESRD if that person does not donate a kidney.

METHODS

We used risk associations from a meta-analysis of seven general population cohorts, calibrated to the population-level incidence of ESRD and mortality in the United States, to project the estimated long-term incidence of ESRD among persons who do not donate a kidney, according to 10 demographic and health characteristics. We then compared 15-year projections with the observed risk among 52,998 living kidney donors in the United States.

RESULTS

A total of 4,933,314 participants from seven cohorts were followed for a median of 4 to 16 years. For a 40-year-old person with health characteristics that were similar to those of age-matched kidney donors, the 15-year projections of the risk of ESRD in the absence of donation varied according to race and sex; the risk was 0.24% among black men, 0.15% among black women, 0.06% among white men, and 0.04% among white women. Risk projections were higher in the presence of a lower estimated glomerular filtration rate, higher albuminuria, hypertension, current or former smoking, diabetes, and obesity. In the model-based lifetime projections, the risk of ESRD was highest among persons in the youngest age group, particularly among young blacks. The 15-year observed risks after donation among kidney donors in the United States were 3.5 to 5.3 times as high as the projected risks in the absence of donation.

CONCLUSIONS

Multiple demographic and health characteristics may be used together to estimate the projected long-term risk of ESRD among living kidney-donor candidates and to inform acceptance criteria for kidney donors. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others.).

LOng-term follow-up after liVE kidney donation (LOVE) study: a longitudinal comparison study protocol

Background

The benefits of live donor kidney transplantation must be balanced against the potential harm to the donor. Well-designed prospective studies are needed to study the long-term consequences of kidney donation.

Methods

The “LOng-term follow-up after liVE kidney donation” (LOVE) study is a single center longitudinal cohort study on long-term consequences after living kidney donation. We will study individuals who have donated a kidney from 1981 through 2010 in the Erasmus University Medical Center in Rotterdam, The Netherlands. In this time period, 1092 individuals donated a kidney and contact information is available for all individuals. Each participating donor will be matched (1:4) to non-donors derived from the population-based cohort studies of the Rotterdam Study and the Study of Health in Pomerania. Matching will be based on baseline age, gender, BMI, ethnicity, kidney function, blood pressure, pre-existing co-morbidity, smoking, the use of alcohol and highest education degree. Follow-up data is collected on kidney function, kidney-related comorbidity, mortality, quality of life and psychological outcomes in all participants.

Discussion

This study will provide evidence on the long-term consequences of live kidney donation for the donor compared to matched non-donors and evaluate the current donor eligibility criteria.

Trial registration

Dutch Trial Register NTR3795.

Kidney and liver transplantation in the elderly

BACKGROUND

Transplant surgery is facing a shortage of deceased donor organs. In response, the criteria for organ donation have been extended, and an increasing number of organs from older donors are being used. For recipients, the benefits of transplantation are great, and the growing ageing population has led to increasing numbers of elderly patients being accepted for transplantation.

METHODS

The literature was reviewed to investigate the impact of age of donors and recipients in abdominal organ transplantation, and to highlight aspects of the fine balance in donor and recipient selection and screening, as well as allocation policies fair to young and old alike.

RESULTS

Overall, kidney and liver transplantation from older deceased donors have good outcomes, but are not as good as those from younger donors. Careful donor selection based on risk indices, and potentially biomarkers, special allocation schemes to match elderly donors with elderly recipients, and vigorous recipient selection, allows good outcomes with increasing age of both donors and recipients. The results of live kidney donation have been excellent for donor and recipient, and there is a trend towards inclusion of older donors. Future strategies, including personalized immunosuppression for older recipients as well as machine preservation and reconditioning of donor organs, are promising ways to improve the outcome of transplantation between older donors and older recipients.

CONCLUSION

Kidney and liver transplantation in the elderly is a clinical reality. Outcomes are good, but can be optimized by using strategies that modify donor risk factors and recipient co-morbidities, and personalized approaches to organ allocation and immunosuppression.

Clinical assessment of lipid profiles in live kidney donors

BACKGROUND

Abnormal serum lipid profiles are an issue in chronic kidney disease (CKD), but the clinical ramifications of dyslipidemia in live kidney donors are unclear. Thus, we explored the relationship between serum lipids and residual renal function in living donors post-nephrectomy.

METHODS

Charts of living donors who underwent nephrectomy between January 2010 and March 2013 were reviewed, targeting those with 6-month follow-up examinations at minimum. Altogether, 282 donors were studied, examining total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) levels assayed before donation by standard techniques. Median follow-up time was 14 months. The relationship between postoperative renal function and allograft biopsy results was assessed. Recursive partitioning was applied to identify optimal cut-off points for each parameter.

RESULTS

Median (interquartile range) serum TC, TG, LDL, and HDL levels were 183 (161-205) mg/dL, 86 (63-131) mg/dL, 108 (92-128) mg/dL, and 53 (44-62) mg/dL, respectively. The glomerular filtration rate at last follow-up was associated with TC (r = -0.187; P = .002) and LDL (r = -0.172; P = .005) levels, but showed no correlation with TG and HDL. Root nodes of TC and LDL determinations in recursive partitioning were 170.5 mg/dL and 80.5 mg/dL, respectively, serving as thresholds for further evaluation. On logistic regression analysis, the likelihood of CKD (glomerular filtration rate < 60 mL/min/1.73 m(2)) at last follow-up was greater in donors with elevated TC and LDL levels (odds ratio = 1.96 and 3.33; P = .021 and .029, respectively).

CONCLUSION

Kidney donors with serum TC and LDL elevations require close observation, given their demonstrable predisposition to CKD after donation.

Vascular management during live donor nephrectomy: an online survey among transplant surgeons

In 2006, a survey from the American Society of Transplant Surgeons disclosed significant and sometimes fatal hemorrhagic events in live donor nephrectomies (LDN) related to failure of clips, leading to the contraindication of the Weck® Hem-o-lok® clip for control of the renal artery during LDN. A survey regarding vascular control techniques, their perceived safety ratings and their failures was sent to 645 European Society for Organ Transplantation members who profiled their profession as "surgeon" and selected "kidney" as organ type. Two hundred forty-three (41%) members responded, of whom 171 (63.3%) independently perform LDN. Their responses were analyzed. For arterial and venous vascular control, the GIA™ and TA™stapler are used most frequently, and were rated the safest. Of the 121 reported hemorrhagic events, slippage and dislodgement of clips occurred at least 58 times, while stapler malfunction occurred at least 40 times. One donor death from hemorrhage related to clip dysfunction was reported. Hemorrhagic complications of LDN with fatal and non-fatal outcomes still occur. Strikingly, many surgeons do not use the vascular closing technique that they consider most safe. Failure of non-transfixion techniques is associated with greater risks for the donor. Control of major vessels in LDN must employ transfixion techniques for optimal donor safety.

Living Donor Kidney Transplantation: Overcoming Disparities in Live Kidney Donation in the US--Recommendations from a Consensus Conference

Despite its superior outcomes relative to chronic dialysis and deceased donor kidney transplantation, live donor kidney transplantation (LDKT) is less likely to occur in minorities, older adults, and poor patients than in those who are white, younger, and have higher household income. In addition, there is considerable geographic variability in LDKT rates. Concomitantly, in recent years, the rate of living kidney donation (LKD) has stopped increasing and is declining, after decades of consistent growth. Particularly noteworthy is the decline in LKD among black, younger, male, and lower-income adults. The Live Donor Community of Practice within the American Society of Transplantation, with financial support from 10 other organizations, held a Consensus Conference on Best Practices in Live Kidney Donation in June 2014. The purpose of this meeting was to identify LKD best practices and knowledge gaps that might influence LDKT, with a focus on patient and donor education, evaluation efficiencies, disparities, and systemic barriers to LKD. In this article, we discuss trends in LDKT/LKD and emerging novel strategies for attenuating disparities, and we offer specific recommendations for future clinical practice, education, research, and policy from the Consensus Conference Workgroup focused on disparities.

Gestational hypertension and preeclampsia in living kidney donors

BACKGROUND

Young women wishing to become living kidney donors frequently ask whether nephrectomy will affect their future pregnancies.

METHODS

We conducted a retrospective cohort study of living kidney donors involving 85 women (131 pregnancies after cohort entry) who were matched in a 1:6 ratio with 510 healthy nondonors from the general population (788 pregnancies after cohort entry). Kidney donations occurred between 1992 and 2009 in Ontario, Canada, with follow-up through linked health care databases until March 2013. Donors and nondonors were matched with respect to age, year of cohort entry, residency (urban or rural), income, number of pregnancies before cohort entry, and the time to the first pregnancy after cohort entry. The primary outcome was a hospital diagnosis of gestational hypertension or preeclampsia. Secondary outcomes were each component of the primary outcome examined separately and other maternal and fetal outcomes.

RESULTS

Gestational hypertension or preeclampsia was more common among living kidney donors than among nondonors (occurring in 15 of 131 pregnancies [11%] vs. 38 of 788 pregnancies [5%]; odds ratio for donors, 2.4; 95% confidence interval, 1.2 to 5.0; P=0.01). Each component of the primary outcome was also more common among donors (odds ratio, 2.5 for gestational hypertension and 2.4 for preeclampsia). There were no significant differences between donors and nondonors with respect to rates of preterm birth (8% and 7%, respectively) or low birth weight (6% and 4%, respectively). There were no reports of maternal death, stillbirth, or neonatal death among the donors. Most women had uncomplicated pregnancies after donation.

CONCLUSIONS

Gestational hypertension or preeclampsia was more likely to be diagnosed in kidney donors than in matched nondonors with similar indicators of baseline health. (Funded by the Canadian Institutes of Health Research and others.).