Rationale and design of TransplantLines: a prospective cohort study and biobank of solid organ transplant recipients

INTRODUCTION

In the past decades, short-term results after solid organ transplantation have markedly improved. Disappointingly, this has not been accompanied by parallel improvements in long-term outcomes after transplantation. To improve graft and recipient outcomes, identification of potentially modifiable risk factors and development of biomarkers are required. We provide the rationale and design of a large prospective cohort study of solid organ transplant recipients (TransplantLines).

METHODS AND ANALYSIS

TransplantLines is designed as a single-centre, prospective cohort study and biobank including all different types of solid organ transplant recipients as well as living organ donors. Data will be collected from transplant candidates before transplantation, during transplantation, at 3 months, 6 months, 1 year, 2 years and 5 years, and subsequently every 5 years after transplantation. Data from living organ donors will be collected before donation, during donation, at 3 months, 1 year and 5 years after donation, and subsequently every 5 years. The primary outcomes are mortality and graft failure. The secondary outcomes will be cause-specific mortality, cause-specific graft failure and rejection. The tertiary outcomes will be other health problems, including diabetes, obesity, hypertension, hypercholesterolaemia and cardiovascular disease, and disturbances that relate to quality of life, that is, physical and psychological functioning, including quality of sleep, and neurological problems such as tremor and polyneuropathy.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the relevant local ethics committee. The TransplantLines cohort study is designed to deliver pioneering insights into transplantation and donation outcomes. The study design allows comprehensive data collection on perioperative care, nutrition, social and psychological functioning, and biochemical parameters. This may provide a rationale for future intervention strategies to more individualised, patient-centred transplant care and individualisation of treatment.

TRIAL REGISTRATION NUMBER

NCT03272841.

Children as donors: a national study to assess procurement of organs and tissues in pediatric intensive care units

A shortage of size-matched organs and tissues is the key factor limiting transplantation in children. Empirical data on procurement from pediatric donors is sparse. This study investigated donor identification, parental consent, and effectuation rates, as well as adherence to the national protocol. A national retrospective cohort study was conducted in all eight Dutch pediatric intensive care units. Records of deceased children were analyzed by an independent donation officer. Seventy-four (11%) of 683 deceased children were found to be suitable for organ donation and 132 (19%) for tissue donation. Sixty-two (84%) potential organ donors had been correctly identified; the parental consent and effectuation rate was 42%. Sixty-three (48%) potential tissue donors had been correctly identified; the parental consent and effectuation rate was 27%. Correct identification increased with age (logistic regression, organs: P = .024; tissues: P = .011). Although an overall identification rate of 84% of potential organ donors may seem acceptable, the variation observed suggests room for improvement, as does the overall low rate of identification of pediatric tissue donors. Efforts to address the shortage of organs and tissues for transplantation in children should focus on identifying potential donors and on the reasons why parents do not consent.

Tolerance of Organ Transplant Recipients to Physical Activity during a High-Altitude Expedition: Climbing Mount Kilimanjaro

BACKGROUND

It is generally unknown to what extent organ transplant recipients can be physically challenged. During an expedition to Mount Kilimanjaro, the tolerance for strenuous physical activity and high-altitude of organ transplant recipients after various types of transplantation was compared to non-transplanted controls.

METHODS

Twelve organ transplant recipients were selected to participate (2 heart-, 2 lung-, 2 kidney-, 4 liver-, 1 allogeneic stem cell- and 1 small bowel-transplantation). Controls comprised the members of the medical team and accompanying family members (n = 14). During the climb, cardiopulmonary parameters and symptoms of acute mountain sickness were recorded twice daily. Capillary blood analyses were performed three times during the climb and once following return.

RESULTS

Eleven of the transplant participants and all controls began the final ascent from 4700 meters and reached over 5000 meters. Eight transplant participants (73%) and thirteen controls (93%) reached the summit (5895m). Cardiopulmonary parameters and altitude sickness scores demonstrated no differences between transplant participants and controls. Signs of hyperventilation were more pronounced in transplant participants and adaptation to high-altitude was less effective, which was related to a decreased renal function. This resulted in reduced metabolic compensation.

CONCLUSION

Overall, tolerance to strenuous physical activity and feasibility of a high-altitude expedition in carefully selected organ transplant recipients is comparable to non-transplanted controls.

Literature overview highlights lack of paediatric donation protocols but identifies common themes that could guide their development

AIM

Paediatric donation is a unique and extremely sensitive process that requires specific knowledge and competencies. Most countries use protocols for organ and tissue donation to ensure optimal care for the donor and family, but these mainly focus on adults. However, the donation process for children differs from adults in many ways. An overview of the literature was performed to identify protocols for the paediatric population.

METHODS

PubMed, Web of Science, EMBASE and the Internet were searched up to March 2016 for papers or other sources in English related to specific organ and tissue donation protocols for children and neonates. This comprised title, abstract and then full-text screening of relevant data.

RESULTS

We included 12 papers and two electronic sources that were mainly from North America and Europe. Most discussed donations after cardiac death. The recurring themes included identifying potential donors, approaching parents, palliative care and collaboration with organ procurement organisations. Most papers called for paediatric donation policies to be standardised.

CONCLUSION

Scientific publications in English on paediatric donation protocols are very scarce. No comprehensive paediatric donation protocol was found. We identified several recurring themes in the literature that could be used to develop such protocols.

Neonatal donation: are newborns too young to be recognized?

Neonatal organ and tissue donation is not common practice in the Netherlands. At the same time, there is a transplant waiting list for small size-matched organs and tissues. Multiple factors may contribute to low neonatal donation rates, including a lack of awareness of this option. This study provides insight into potential neonatal organ and tissue donors and reports on how many donors were actually reported to the procurement organization. We performed a retrospective analysis of the mortality database and medical records of two largest neonatal intensive care units (NICUs) in the Netherlands. This study reviewed records of neonates with a gestational age >37 weeks and weight >3000g who died in the period from January 1, 2005 through December 31, 2016. During the study period, 259 term-born neonates died in the two NICUs. In total, 132 neonates with general contra-indications for donation were excluded. The medical records of 127 neonates were examined for donation suitability. We identified five neonates with documented brain death who were not recognized as potential organ and/or tissue donors. Of the remaining neonates, 27 were found suitable for tissue donation. One potential tissue donor had been reported to the procurement organization. In three cases, the possibility of donation was brought up by parents.Conclusion: A low proportion (2%) of neonates who died in the NICUs were found suitable for organ donation, and a higher proportion (12%) were found suitable for tissue donation. We suggest that increased awareness concerning the possibility of neonatal donation would likely increase the identification of potential neonatal donors. What is Known: • There is an urgent need for very small organs and tissues from neonatal donors What is New: • A number of neonates who died in the NICU were suitable organ or/and tissue donors but were not recognized as donors. • Knowledge on neonatal donation possibilities is also important for proper counseling of parents who sometimes inquire for the possibility of organ and tissue donation.

Lack of knowledge and experience highlights the need for a clear paediatric organ and tissue donation protocol in the Netherlands

Aim

This study explored the attitudes of medical professionals to organ and tissue donation in paediatric intensive care units (PICUs) and neonatal intensive care units (NICUs) in the Netherlands. It also examined their compliance with the existing Dutch donation protocol and assessed whether a paediatric donation protocol was needed.

Methods

We invited 966 professionals working in all eight PICUs and the two largest NICUs to complete an online survey from December 2016 until April 2017.

Results

A quarter (25%) took part and they included PICU intensivists, neonatologists, nurses and other health and allied professionals. Most were female and nurses. More than half (54%) of the PICU respondents considered paediatric organ donation to be very important and 53% supported tissue donation. In contrast, only 22% of the NICU respondents believed that both neonatal organ and tissue donation were very important. Familiarity and compliance with the existing national donation protocol were low. PICU nurses had significantly less experience than PICU intensivists and felt less comfortable with the donation process. None of the NICU respondents had prior donation experience.

Conclusion

Paediatric intensive care units and NICU professionals lack specialised knowledge and experience on organ and tissue donation. A comprehensive and clear paediatric donation protocol is clearly needed.

An online explorative study towards parents' opinions about organ donation: from individual decisions to family discussions

BACKGROUND

Parental decisions about organ donation by their child are influenced by many factors. One of these factors may be a previous discussion under non-crisis circumstances. The question then arises whether parents have thought about this topic for themselves and discussed it with each other or with their child.

METHODS

An initial exploratory Internet survey to explore these discussions, parental opinions about school lessons on donation, the age threshold for a child to decide about donation, and determinants that influence these aspects. Questionnaire was sent to 14,000 panel members. We selected respondents with children younger than 16 years old.

RESULTS

Questionnaire response rate was 35%. Of all 1146 respondents with children, 84% had discussed the topic with their partner and, on average, 46.5% had discussed this with their child aged 10-16 years old. Religion and educational level of the parents were not related. Sixty-nine percent of parents were positive towards school lessons. Most of the children were allowed to decide for themselves at the age of 15/16 years old.

CONCLUSION

Family discussions between spouses about donation do occur frequently, however, discussion with children can be improved. If desired, triggers for beginning these conversations could be provided through public information and school education, which would also contribute to health literacy on this subject.

Proton Pump Inhibitor Use, Fatigue, and Health-Related Quality of Life in Kidney Transplant Recipients: Results From the TransplantLines Biobank and Cohort Study

RATIONALE & OBJECTIVE

Prior studies report that the use of proton pump inhibitors (PPIs) can adversely affect gut microbiota and gastrointestinal uptake of micronutrients, in particular iron and magnesium, and are used frequently by kidney transplant recipients. Altered gut microbiota, iron deficiency, and magnesium deficiency have been implicated in the pathogenesis of chronic fatigue. Therefore, we hypothesized that PPI use may be an important and underappreciated cause of fatigue and reduced health-related quality of life (HRQoL) in this population.

STUDY DESIGN

Cross-sectional study.

SETTING & PARTICIPANTS

Kidney transplant recipients (≥1 year after transplantation) enrolled in the TransplantLines Biobank and Cohort Study.

EXPOSURE

PPI use, PPI type, PPI dosage, and duration of PPI use.

OUTCOME

Fatigue and HRQoL, assessed using the validated Checklist Individual Strength 20 Revised questionnaire and Short Form-36 questionnaire.

ANALYTICAL APPROACH

Logistic and linear regression.

RESULTS

We included 937 kidney transplant recipients (mean age 56±13 years, 39% female) at a median of 3 (1-10) years after transplantation. PPI use was associated with fatigue severity (regression coefficient 4.02, 95% CI, 2.18 to 5.85, P<0.001), a higher risk of severe fatigue (OR 2.05, 95% CI, 1.48 to 2.84, P<0.001), lower physical HRQoL (regression coefficient-8.54, 95% CI, -11.54 to-5.54, P<0.001), and lower mental HRQoL (regression coefficient-4.66, 95% CI, -7.15 to-2.17, P<0.001). These associations were independent of potential confounders including age, time since transplantation, history of upper gastrointestinal disease, antiplatelet therapy, and the total number of medications. They were present among all individually assessed PPI types and were dose dependent. Duration of PPI exposure was only associated with fatigue severity.

LIMITATIONS

Residual confounding and inability to assess causal relationships.

CONCLUSIONS

PPI use is independently associated with fatigue and lower HRQoL among kidney transplant recipients. PPI use might be an easily accessible target for alleviating fatigue and improving HRQoL among kidney transplant recipients. Further studies examining the effect of PPI exposure in this population are warranted.