Long-term follow-up after live kidney donation; A matched, controlled study on renal function and quality of life.

Living donors are healthy people necessitating a high standard of care to
guarantee their quality of life after donation. Moreover, optimizing the
quality of life after an operation performed for the well-being of another
individual is the legitimization for any living organ donor program. In the
last decade multiple innovations in live donor nephrectomy have been
introduced, thereby expanding the donor pool. However, little is known on the
long-term effects of live kidney donation, regarding kidney function, diabetes,
hypertension, survival and quality of life. Determining the effects of live
kidney donation on long term is pivotal to continue the expanding inclusion of
living donors in the kidney donation programme. Screening for potential donors
will be more complete and effective when a more accurate risk assessment can be
provided. Also, accurate information to donors and corresponding recipients on
these risks is a prerequisite to include donors with minor risk factors, like
hypertension, obesity and more in the national live kidney donation programme.
With the availability of the live kidney donor cohort, the Rotterdam
Study-cohort in Rotterdam and the SHIP-study cohort we have the unique
opportunity to determine the long term effects of kidney donation. For the
first time it will be possible to study the long term consequences live kidney
donation in a matched and prospective study design. This study will offer a
reference indicating safety criteria related to living kidney donation in the
Western world.

To assess the long-term consequences of live kidney donation, regarding kidney
function, survival, hypertension, diabetes, systolic and diastolic blood
pressure, mental state and quality of life.

Long-term follow-up in donors and donors with comorbidities: a prospective,
matched cohort study.

Patients: All donors in our database are eligible for inclusion in this study.
All donors were pre-operatively screened by a nephrologist and surgeon. A
medical psychologist is consulted on indication and in case of unspecified
donation. Radiological evaluation of their kidneys took place by
ultrasonography, magnetic resonance imaging and computed tomography
angiography. Donor nephrectomy was performed by using a variation of open and
endoscopic techniques. The RS-II and RS-III cohort will be used as a control
group in this study for donors aged 45 and higher. In total 3011 controls have
been included in the RS-II cohort in 2000-2001, they were followed up on in
2004-2005. The RS-III cohort started including for this cohort in 2006, this
time with inhabitants aged 45 years and over. Inclusion ended in December 2008
and 3,932 participants have been included in this third cohort. The first
follow-up moment of this cohort will start in 2012 and is due to finish in
2013. The first cohort of the SHIP-study will be used as a control group in
this study for donors aged 44 and younger. This cohort includes 4,310
participants aged 20-70 years.

Methods: Donor characteristics and follow-up data will be checked and updated
in accordance with the hospital*s electronic patient system. As soon as
approval of the Medical Ethical Committee has been acquired, donors will be
contacted and asked to participate in this study. If they choose to
participate, a follow-up visit at our outpatient clinic will be scheduled.
During this visit blood and urine samples will be taken and an ultrasonography
of the remaining kidney will be performed. Donors will undergo blood pressure
tests and receive a questionnaire on their drug usage, the development of
cardiovascular disease, quality of life and mental state. All answers on these
questionnaires will be discussed with a physician. Furthermore, their complete
medical history will be checked. Non-responders will be contacted and asked if
they object if information from their medical records will be used for this
study (e.g. kidney function from blood and urine analysis, blood pressure,
weight, medication use, incidence of comorbidity) and if they want to fill out
a quality of life questionnaire. Controls will be selected and matched for age,
gender, BMI, ethnicity and pre-existing co-morbidity. After matching, all study
parameters will be compared to our control group. A 1 on 4 match is our goal,
however if the available data in the control group is insufficient, this will
have to be revised downwards. Donor survival will be crosschecked in the
municipal registry and compared to the general Dutch population. All data
regarding the controls will be acquired from the Rotterdam Study and SHIP study
database.

Measurements: Systolic and diastolic tension will be measured using a
datascope. Blood samples will be taken and serum creatinine, glucose and eGFR
according to MDRD and CKD-EPI-formula will be measured. Protein/creatinin
ratio, glucose, creatinine and microalbuminuria will be measured in the donor*s
urine. Development of related co-morbidity, drug usage etc. will be assessed by
a questionnaire, with the help of a physician. Quality of life will be measured
with the SF-12 and EuroQoL questionnaire. Mental state will be measured with
the HADS, PSIQ, CESD (or BDI if donor is aged 44 or younger), questionnaire on
sexuality and happiness.

Statistical considerations: The Kaplan-Meier method will be used to calculate
donor and control survival, differences will be tested using the log-rank test.
Multivariate Cox regression analysis will be performed to assess independent
prognostic factors regarding kidney function and comorbidities. Differences
between groups will be analyzed using the paired-samples T-test and the one-way
ANOVA.

Ten-year follow-up on quality of life.
All 143 donors that were included in the Lido-trial between 2001 and 2003 are
eligible for inclusion in this study; deceased or emigrated donors will be
excluded. All donors were pre-operatively screened by a nephrologist. A medical
psychologist is consulted on indication and in case of unspecified donation.
Radiological evaluation of their kidneys took place by ultrasonography,
magnetic resonance imaging and computed tomography angiography. Donor
nephrectomy was performed by either mini-incision or laparoscopically.
Methods: Donors filled out two questionnaires regarding quality of life
pre-operatively and at 1, 3, 6 and 12 months post-operatively. Ten years after
donation donors will be contacted by mail. They will be requested to fill out
the same two questionnaires; non-responders will be contacted again by mail and
telephone. A response rate of 70% will be deemed acceptable.
Statistical considerations: Quality of life scores will be adjusted for
baseline values and gender. A logistic regression analysis will be carried out.
Categorical variables will be compared using the Chi square test, continuous
variables will be tested using the Mann Whitney U test and repeated
measurements will be tested by repeated measurements ANOVA, using SPSS mixed
models.

Not applicable