1
Running Head: Renal function after partial nephrectomy, Yu et al.
Significance of Glucose Control for Perioperative and Long-Term Renal Functions after
Nephron-sparing Surgery for Renal Cancer in Patients with Diabetes
Seong Hyeon Yu, Seong Jong Eun, Taek Won Kang
Department of Urology, Chonnam National University Medical School, Chonnam National
University Hospital, Gwangju, Korea
Keywords: nephrons, sparing, surgery, risk factors, kidney, function
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ABSTRACT
Purpose: This study aimed to evaluate the predictive factors for perioperative and long-term
renal functions after nephron-sparing surgery (NSS).
Materials and Methods: The clinical records of 379 patients who underwent NSS for a single
renal tumor with a normal contralateral kidney between 2009 and 2016 were retrospectively
analyzed. After surgery, the occurrence of acute kidney injury (AKI) within 7 days and the
progression of chronic kidney disease (CKD) 5 years later were assessed using serum creatinine
(S-Cr) levels. Perioperative AKI was defined as an increase in the S-Cr level by ≥ 0.3 mg/dL
or 1.5–1.9 times the baseline value. CKD was defined as the estimated glomerular filtration
rate (eGFR) decreasing from > 60 mL/min/1.73 m2 to < 60 mL/min/1.73 m2.
Results: Changes in the eGFR were assessed during 5 years after surgery. Among 379 patients,
81 (21.4%) patients presented diabetes mellitus (DM), and 30 (7.92%) experienced
uncontrolled DM. The AKI occurrence and CKD progression were observed in 50 (13.2%)
patients and 79 (20.8%) patients, respectively. Multivariable analyses revealed that female
gender (95% confidence interval [CI]: 0.16–0.91, odds ratio [OR] = 0.39, P = 0.029),
uncontrolled DM (95% CI: 1.05–6.60, OR = 2.63, P = 0.039), and intermediate NePhRO score
(95% CI: 1.07–3.80, OR = 2.02, P = 0.03) were associated with perioperative AKI. In addition,
old age (95% CI: 1.10–1.18, OR = 1.14, P < 0.001) and uncontrolled DM (95% CI: 1.84–11.4,
OR = 4.57, P = 0.001) were associated with long-term CKD progression.
Conclusion: Uncontrolled DM is the only predictive factor for perioperative and long-term
renal functions after nephron-sparing surgery.
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INTRODUCTION
The incidence of renal tumors has increased during the past decades. (1) Recently, the
development of imaging modalities has led to a decrease in the size and stage migration of
newly detected incidental renal tumors. Nephron-sparing surgery (NSS) is currently the
treatment of choice for the surgical management of these earlier diagnosed small renal tumors
because of its good overall survival (OS) with no compromise in oncologic results and minimal
renal function deterioration (RFD). (2) Several previous studies have reported that RFD after
NSS may depend on the patient’s body mass index (BMI), radiologic size of the tumor, quantity
of preserved functional parenchyma volume, ischemic time during surgery, and length of
surgery. (3-5) The incidence of type 2 diabetes mellitus (T2DM), one of the most important
causes of kidney disease, has also increased markedly in recent decades. (6) However, a few
reports have mentioned the role of underlying T2DM affecting RFD after NSS. (7,8) In addition,
along with T2DM, well-controlled blood sugar levels may also play an important role. This
study aimed to determine the factors for RFD after NSS in patients with a renal tumor.
MATERIALS AND METHODS
1. Subjects and the study design
This retrospective study screened the patients who underwent NSS for a single renal tumor in
our hospitals (Chonnam National University Hospital and Chonnam National University
Hwasun Hospital, Korea) between January 2009 and December 2016. A total of 478 patients
were initially enrolled in this study. Detailed medical history, including age, sex, BMI,
hypertension, diabetes mellitus (DM), the operation site, total operation time, operation
methods, preoperative hemoglobin level, pathologic T stage, the occurrence of perioperative
AKI, and progression of postoperative long-term chronic kidney disease (CKD), were collected
4
from each patient’s medical record. Patients with follow-up loss within 5 years, preoperative
CKD, bilateral renal tumors, and lack of medical records for perioperative AKI and
postoperative long-term CKD were excluded from the study. A total of 379 out of 478 patients
were found eligible for the final analysis.
2. Data collection, definition, and the assessment of renal functions
Serum creatinine (SCr) levels were measured at the following periods: preoperatively, during
admission, and postoperative annual follow-ups during 5 years. The zonal NePhRO score
(comprising the Nearness to collecting system and Physical zones, Radius, and Organization
of the tumor) before surgery for predicting the surgical complexity of a renal lesion was
calculated as low (4–6), intermediate (7–9), or high (10–12). (9) Kidney cancer staging was
based on the American Joint Committee on Cancer staging manual. (10) Uncontrolled DM was
defined as the level of glycosylated hemoglobin (HbA1c) in the blood maintained at ≥ 7%. (11)
Perioperative AKI within 7 days from partial nephrectomy was defined and classified
according to the severity as stage 1 (increase in the SCr levels by ≥ 0.3 mg/dL or 1.5–1.9 times
the baseline value), stage 2 (increase in the SCr level by 2.0–2.9 times the baseline value), and
stage 3 (increase in the SCr level by ≥ 4.0 mg/dL or ≥ 3.0 times the value at baseline or initiation
of renal replacement therapy). (12) The urine output was not accounted for because the data was
collected retrospectively. Postoperative long-term CKD was defined as a decrease in the
estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2 5 years later from partial
nephrectomy in patients with a preoperative eGFR > 60 mL/min/1.73 m2.
3. Statistical Analyses
Statistical analyses were performed using STATA version 16.1 (StataCorp., College Station,
5
Texas, USA). Continuous variables are represented as the mean values with standard deviations
(SD); categorical variables are presented as frequencies (%). The Student’s t-test for continuous
variables and Pearson chi-square test for categorical variables were used to compare the clinical
characteristics according to the occurrence of perioperative AKI and progression of
postoperative long-term CKD. In addition, using multivariable logistic regression analysis by
selecting significant variables through univariate analysis, the predictive factors for
perioperative and postoperative long-term renal outcomes were analyzed. Statistical
significance was set at p<0.05 for all analyses.
4. Ethics statement
The study protocol was reviewed and approved by the Institutional Review Board (IRB) of the
Chonnam National University Hospital Research Institute of Clinical Medicine (IRB approval
no.: CNUH-2021-367). The study was performed in accordance with the Declaration of
Helsinki and the Ethical Guidelines for Clinical Studies.
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RESULTS
Characteristics of the patients who were eligible for the final analysis are summarized in Table
1. The patients’ mean age and BMI were 58.4 ± 11.9 years and 25.0 ± 3.09 kg/m2, respectively.
Among 379 patients, 155 (40.9%), 81 (21.4%), and 30 (7.92%) patients presented hypertension,
DM, and uncontrolled DM, respectively. According to preoperative NePhRO score calculation,
188 (49.6%) patients exhibited intermediate risk, with ≥ 7 points. The mean operation time was
124.3 ± 45.1 min, and 277 (73.1%) patients underwent laparoscopic surgery. The numbers of
patients exhibiting stages T1a, T1b, T2, and T3 renal cancer were 315 (83.1%), 59 (15.6%), 3
(0.8%), and 2 (0.5%), respectively. Regarding the perioperative and postoperative long-term
renal functions, 50 (13.2%) patients experienced perioperative AKI, while 79 (20.8%) patients
showed progression to postoperative long-term CKD.
Based on the results of clinical features according to the perioperative AKI occurrence, the
perioperative AKI group was significantly associated with old age (57.9 ± 11.7 years vs. 62.0
± 13.0 years, P = 0.021), female sex (72.0% vs. 86.0%, P = 0.036), intermediate risk of
NePhRO score (47.4% vs. 64.0%, P = 0.029), and uncontrolled DM (6.7% vs. 16.0%, P =
0.033) compared to the other group (Table 2). Furthermore, comparing the clinical features
according to the progression of postoperative long-term CKD revealed that the postoperative
long-term CKD group was significantly associated with old age (55.8 ± 11.3 years vs. 68.5 ±
8.16 years, P < 0.001), low preoperative hemoglobin (7.3% vs. 22.8%, P < 0.001), hypertension
(37.7% vs. 53.2%, P = 0.013), and uncontrolled DM (5.0% vs. 19.0%, P < 0.001) (Table 3).
The predictive factors associated with perioperative and postoperative long-term renal
functions after NSS are detailed in Tables 4 and 5. Univariate analyses revealed a significant
association of old age, male sex, intermediate risk of NePhRO score, and uncontrolled DM
with the occurrence of perioperative AKI (P = 0.023, P = 0.041, P = 0.031, and P = 0.018,
7
respectively). In addition, multivariable analyses showed female sex (95% confidence interval
[CI]: 0.16–0.91, odds ratio [OR]: 0.39, P = 0.029), intermediate risk of NePhRO score (95%
CI: 1.07–3.80, OR 2.02, P = 0.03), and uncontrolled DM (95% CI: 1.05–6.60, OR 2.63, P =
0.039) as significant factors associated with perioperative and postoperative long-term renal
functions after NSS. Regarding postoperative long-term CKD, univariate analyses revealed old
age, hypertension, low preoperative Hgb, controlled DM, and uncontrolled DM as significant
factors (P < 0.001, P = 0.013, P < 0.001, P = 0.004, and P < 0.001, respectively). However,
multivariable analyses showed only old age (95% CI: 1.10–1.18, OR 1.14, P < 0.001) and
uncontrolled DM (95% CI: 1.84–11.4, OR 4.57, P = 0.001) as significant factors associated
with the progression of postoperative long-term CKD.
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DISCUSSION
With the development of imaging modalities and growing interest in individual health
examinations, the incidence of newly detected incidental renal tumors is increasing. NSS is
recommended in the guidelines on the management of renal cell carcinoma as the standard
treatment for clinical T1 stage renal tumors. (13) Furthermore, NSS has the advantage of
preserving the renal function and potential cardiovascular and OS with CKD avoidance. (2,14)
However, despite successful operations, RFD after NSS is common in some cases. Therefore,
in the present study, we focused on perioperative and long-term renal functions after NSS, and
our results showed that uncontrolled DM is the only independent factor affecting both functions.
To date, several studies reported the possible predictive factors for RFD after NSS, including
the patient’s BMI and comorbidities, renal tumor size, the quantity of preserved functional
parenchyma volume, intraoperative ischemic time, and total surgical time. (3-5) Among these
factors, many physicians have suggested that RFD can be minimized by modifiable surgery-
related factors, such as reduced warm ischemic time (WIT). Theoretically, warm ischemia-
related RFD can be explained via postulated pathophysiological mechanisms, such as
mechanical obstruction of microvessels by leukocytes and platelets and postischemic
vasoconstriction with endothelial damage followed by reperfusion injury. (15) Porpiglia et al.
reported that kidney damage occurs during laparoscopic partial nephrectomy (LPN) when WIT
is more than 30 min. (16) Erdem et al. included 127 patients who underwent elective LPN and
reported that prolonged WIT (> 27.75 min) was the strongest independent predictor of
postoperative CKD. (17) Based on these results, it has been recently recommended to avoid WIT
for more than 30 min.
There is increasing evidence that the quantity and quality of preserved renal parenchyma play
important roles in RFD in patients who received NSS; hence, the effects of WIT on RFD have
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been debated continuously. In an animal study with a solitary kidney model, WIT up to 90 min
was well-tolerated by nephrons, and postoperative renal function was recovered within only 2
weeks. (18) Similarly, prolonged WIT (>27.75 min) in the human kidney can lead to a renal
functional loss in the early postoperative period, but this was recovered during the intermediate
term follow-up period of 2 years in patients with a contralateral functioning kidney. (17) Erdem
et al. recently reported that although overextended WIT (> 40 min) can cause significant
postoperative RFD, the functional loss can be recovered at the median follow-up period of 3
years in patients with contralateral functioning kidneys. (7) Furthermore, Dong et al. found that
patients with WIT > 35 min have lower median recovery from ischemia, although not
significantly different from patients with a WIT < 35 min, and warm ischemia was associated
with only a 2.5% decrease in functional recovery for every additional 10 min. (19) Considering
these results, we carefully suggested that WIT is not a significant predictive factor for long-
term renal function after NSS. In the present study, the investigated WIT was not > 40 min
(mean WIT; 24.3 ± 8.88 minutes, data not shown), and total surgery time was not associated
with perioperative and long-term renal functions after NSS.
The surgical complexity of a renal tumor can be a surgery-related factor affecting RFD after
NSS. This may cause intraoperative complications, including increased blood loss, prolonged
ischemia time, and a greater loss of functional renal parenchyma, and thereby affect
perioperative and long-term renal functions (9,20) In the present study, the surgical complexity
of a renal tumor was calculated before surgery, and more than intermediate risk was associated
with the perioperative AKI occurrence. However, its association with the progression of
postoperative long-term CKD was not observed. This might be explained by the findings that
an early postoperative renal functional loss due to surgery-related factors could be recovered
at the long-term follow-up period.
10
Recently, patient-related factors of RFD after NSS, such as BMI, hypertension, and DM, have
also been considered. In fact, hypertension and DM are the most common patient-related
factors affecting renal functions and are known to be significantly associated with CKD. (21) In
particular, T2DM has been known to significantly reduce the OS in patients with renal cell
carcinoma. (22) In line with these results, several studies have evaluated the associations among
patient-related factors and RFD after NSS. Demirjian et al. classified patients presenting a new
CKD after NSS into two groups, including medically- and surgically-induced CKD. The
surgically-induced CKD group had a lower rate of functional decline and less impact on
survival than medically-induced CKD groups. (23) Similarly, Satasivam et al. found that DM
was one of the crucial independent risk factors, and 42% of patients with DM progressed to
stage 3 or greater CKD, whereas WIT had no impact on RFD. (8) In addition, DM has been
reported as the only independent predictor for both postoperative and long-term renal functions
in patients who underwent NSS, regardless of WIT. (7) These findings might indicate that the
patient-related factor has a more important role in the CKD progression during the follow-up
period, whereas the surgery-related factor has only a temporary role in postoperative short-
term RFD.
To our knowledge, no study has yet reported the association between blood sugar control in
diabetic patients and perioperative and long-term renal functions after NSS. Therefore, this
study is possibly the first report stating that uncontrolled DM has a significant effect on RFD
after NSS in patients with normal baseline kidney function. Comparisons of clinical features
according to perioperative AKI and postoperative long-term CKD in this study showed that the
percentage of uncontrolled DM patients was significantly higher in both groups. Furthermore,
in multivariable analyses, uncontrolled DM was found to be the only predictive factor affecting
both states. Patients with uncontrolled DM presented approximately 4.5-fold greater risk than
11
patients without DM, especially in postoperative long-term CKD progression at 5 years. As in
previous studies, although uncontrolled DM can be thought to further affect RFD by causing
serious microvascular complications, (11,24) several prospective, pathophysiologic, or
molecular-level studies on the correlation of associations among uncontrolled DM,
perioperative AKI, and postoperative long-term CKD should be conducted in the future.
In the present study, 50 patients presented perioperative AKI, and 79 patients showed
progression to postoperative long-term CKD. However, only 22 patients with perioperative
AKI showed progression to postoperative long-term CKD, while 59 patients experienced a new
progression of CKD during the long-term follow-up period of 5 years. These finding implies
that preserving the functional renal volume alone might not be sufficient; optimized DM
control with medical reno-protection is essential for preventing RFD after surgery. Additionally,
further studies are needed to evaluate the patient-related factors of postoperative renal function.
The present study has several limitations. First, it was a retrospective study with relatively
small sample size and heterogeneity in patient characteristics and conducted at a single
institution. Despite partial nephrectomy being performed by urologic specialists, the quality of
these tasks could present inter-performer biases. Second, data on preoperative proteinuria,
which is a significant contributor to kidney function, were not considered. (25) Third, the
severity of hypertension, which is also a predictive factor for CKD, was not assessed. (21) In the
present study, hypertension was not found to be associated with perioperative AKI and
postoperative long-term CKD. Fourth, we did not consider the ischemia time, because it was
not available for approximately 25% in our database. Instead of ischemia time, we assessed the
total surgery time as predictive factor, it was not significant. Finally, we did not use volumetric
analyses or scintigraphy methods to assess preserved ipsilateral renal function. However,
uncontrolled DM being first reported as the predictive factor of postoperative renal function
12
after NSS, especially during the long-term follow-up period (5 years), is the strength of this
study.
13
CONCLUSION
In the present study, uncontrolled DM was the only predictive factor for perioperative and
long-term renal functions in patients after NSS. Based on this result, physicians should consider
optimized DM control with medical reno-protection to be important for minimal postoperative
RFD at the time of counseling of renal cell carcinoma patients scheduled for NSS.
SUMMARY
In the presents study, we investigated the predictive factors for perioperative and long-term
renal functions after nephron-sparing surgery. We identified that uncontrolled DM is the
independent factor affecting both functions. Our results can emphasize the significance of
glucose control after nephron-sparing surgery for patients with renal cancer.
CONFLICTS OF INTEREST: The authors have nothing to disclose.
ACKNOWLEDGMENTS
This study was supported by a grant (CRI 15 002-1) received from the Chonnam National
University Hospital Biomedical Research Institute.
AUTHOR CONTRIBUTION
Research conception and design, Data acquisition, Statistical analysis: Seong Hyeon Yu,
Taek Won Kang
Data analysis and interpretation: Seong Hyeon Yu, Seong Jong Eun
Drafting of the manuscript: Seong Hyeon Yu,
Critical revision of the manuscript for scientific and factual content: Taek Won Kang
Orcid ID
Seong Hyeon Yu https://orcid.org/0000-0002-1761-2025
https://orcid.org/0000-0002-1761-2025
14
Seong Jong Eun https://orcid.org/0000-0003-1476-6608
Taek Won Kang https://orcid.org/0000-0002-7708-819X
https://orcid.org/0000-0003-1476-
https://orcid.org/0000-0002-7708-819
15
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15. Derweesh IH, Novick AC. Mechanisms of renal ischaemic injury and their clinical
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Dysfunction in Elective Laparoscopic Partial Nephrectomy Recovers During
Intermediate-Term Follow-Up. J Endourol. 2015;29:1083-90.
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Corresponding author:
Taek Won Kang, MD, PhD
Department of Urology, Chonnam National University Hospital and Medical School
18
42, Jebong-ro, Dong-gu, Gwangju #61469, South Korea
Telephone: +82-62-220-6705
FAX: +82-62-227-1643
E-mail: sydad@hanmail.net
Table 1. Characteristics of the patients who received partial nephrectomy for renal tumor
Variables Values
(N = 379)
Age (years) 58.4 ± 11.9
BMI (kg/m2) 25.0 ± 3.09
Sex
Male 280 (73.9)
Comorbidities
HTN 155 (40.9)
DM 81 (21.4)
Uncontrolled DM 30 (7.92)
Site
Right 187 (49.3)
Methods of surgery
Open 102 (26.9)
Laparoscopy 277 (73.1)
mailto:sydad@hanmail.net
19
OP time (min) 124.3 ± 45.1
Pre OP hemoglobin (mg/dL) 14.0 ± 1.63
Pre OP NePhRO score
Low 191 (50.4)
Intermediate 188 (49.6)
Pathologic T stage
T1a 315 (83.1)
T1b 59 (15.6)
T2 3 (0.8)
T3 2 (0.5)
Post OP AKI 50 (13.2)
Post OP CKD (5 years follow up) 79 (20.8)
AKI: Acute kidney injury, BMI: body mass index, CKD: Chronic kidney disease, DM: diabetes
mellitus, HTN: hypertension, OP: operation; Pre OP: preoperative, Post OP: postoperative
Data are represented as mean ± standard deviation or n (%).
20
Table 2. Comparisons of the clinical features based on the occurrence of perioperative AKI
Variablesa No (n=329) Yes (n=50) p-value
Age (years) 57.9 ± 11.7 62.0 ± 13.0 0.021
BMI (kg/m2) 0.203
< 25 183 (55.6) 23 (46.0)
≥25 146 (44.4) 27 (54.0)
Sex 0.036
Male 237 (72.0) 43 (86.0)
Female 92 (28.0) 7 (14.0)
HTN 130 (39.5) 25 (50.0) 0.160
DM 0.033
No 265 (80.5) 33 (66.0)
Controlled DM 42 (12.8) 9 (18.0)
Uncontrolled DM 22 (6.7) 8 (16.0)
Site 0.686
Right 161 (48.9) 26 (52.0)
Left 168 (51.1) 24 (48.0)
Methods of surgery 0.384
Open 86 (26.1) 16 (32.0)
Laparoscopy 243 (73.9) 34 (68.0)
OP time (min) 122.9 ± 42.83 133.5 ± 57.23 0.210
Pre OP Hemoglobin (normal
range)
298 (90.6) 41 (82.0) 0.066
Pre OP NePhRO score 0.029
21
Low 173 (52.6) 18 (36.0)
Intermediate 156 (47.4) 32 (64.0)
Pathologic T stage 0.150
T1a 277 (84.2) 38 (76.0)
T1b-T3 52 (15.8) 12 (24.0)
AKI: Acute kidney injury, BMI: body mass index, DM: diabetes mellitus, HTN: hypertension,
OP: operation; Pre OP: preoperative
Data are represented as mean ± standard deviation or n (%).
a The Student’s t-test for continuous variables and Pearson chi-square test for categorical
variables were used to compare the clinical characteristics
22
Table 3. Comparisons of the clinical features based on the progression of postoperative long-
term CKD
Variablesa No (n=300) Yes (n=79) p-value
Age (years) 55.8 ± 11.3 68.5 ± 8.16 <0.001
BMI (kg/m2) 0.199
< 25 158 (52.7) 48 (60.8)
≥25 142 (47.3) 31 (39.2)
Sex 0.182
Male 217 (72.3) 63 (79.8)
Female 83 (27.7) 16 (20.2)
HTN 113 (37.7) 42 (53.2) 0.013
DM <0.001
No 251 (83.7) 47 (59.5)
Controlled DM 34 (11.3) 17 (21.5)
Uncontrolled DM 15 (5.0) 15 (19.0)
Site 0.609
23
Right 146 (48.7) 41 (51.9)
Left 154 (51.3) 38 (48.1)
Methods of surgery 0.384
Open 79 (26.3) 23 (29.1)
Laparoscopy 221 (73.7) 56 (70.9)
OP time (min) 125.04 ± 43.82 121.27 ± 49.63 0.508
Pre OP Hemoglobin (normal
range)
278 (92.7) 61 (77.2) <0.001
Pre OP NePhRO score 0.085
Low 158 (52.7) 33 (41.8)
Intermediate 142 (47.3) 46 (58.2)
Pathologic T stage 0.150
T1a 251 (83.7) 64 (81.0)
T1b-T3 49 (16.3) 15 (19.0)
CKD: Chronic kidney disease, BMI: body mass index, DM: diabetes mellitus, HTN:
hypertension, OP: operation; Pre OP: preoperative
Data are represented as mean ± standard deviation or n (%).
a The Student’s t-test for continuous variables and Pearson chi-square test for categorical
variables were used to compare the clinical characteristics
24
Table 4. Clinical factors associated with the occurrence of perioperative AKI
Variables Univariate analysis Multivariate analysis
Odds ratio (95%
CI)
p-value Odds ratio (95%
CI)
p-value
Age (years) 1.03 (1.00–1.06) 0.023 1.02 (1.00–1.05) 0.082
Sex
Male Reference
25
Female 0.42 (0.18–0.97) 0.041 0.39 (0.16–0.91) 0.029
BMI (kg/m2)
< 25 Reference
≥ 25 1.47 (0.81–2.67) 0.205
Site
Right Reference
Left 0.88 (0.49–1.60) 0.687
Methods of surgery
Open Reference
Laparoscopy 0.75 (0.40–1.43) 0.385
HTN 1.53 (0.84–2.78) 0.162
DM
No Reference
Controlled DM 1.72 (0.77–3.85) 0.187
Uncontrolled DM 2.92 (1.20–7.09) 0.018 2.63 (1.05–6.60) 0.039
OP time (min) 1.00 (1.00–1.01) 0.120
Pre OP Hemoglobin
Low abnormal Reference
Normal 0.47 (0.21–1.07) 0.071
Pre OP NePhRO
score
Low Reference
Intermediate 1.97 (1.06–3.65) 0.031 2.02 (1.07-3.80) 0.03
Pathologic T stage
26
T1a Reference
T1b-T3 1.68 (0.82–3.43) 0.153
AKI: Acute kidney injury, BMI: body mass index, CI: confidence interval, CKD: Chronic
kidney disease, DM: diabetes mellitus, HTN: hypertension, OP: operation; Pre OP:
preoperative, Post OP: postoperative
27
Table 5. Clinical factors associated with the progression of postoperative long-term CKD
Variables Univariate analysis Multivariate analysis
Odds ratio (95%
CI)
p-value Odds ratio (95%
CI)
p-value
Age (years) 1.14 (1.10–1.18) <0.001 1.14 (1.10–1.18) <0.001
Sex
Male Reference
Female 0.66 (0.36–1.21) 0.184
BMI (kg/m2)
< 25 Reference
≥ 25 0.72 (0.43–1.19) 0.200
Site
Right Reference
Left 0.88 (0.54–1.44) 0.609
Methods of surgery
Open Reference
Laparoscopy 0.87 (0.50–1.51) 0.620
HTN 1.88 (1.14–3.10) 0.013 1.01 (0.55–1.83) 0.983
DM
No Reference
Controlled DM 2.67 (1.38–5.17) 0.004 1.61 (0.75–3.48) 0.217
Uncontrolled DM 5.34 (2.45–11.66) <0.001 4.57 (1.84–11.4) 0.001
OP time (min) 1.00 (0.99–1.00) 0.507
28
Pre OP Hemoglobin
Low abnormal Reference
Normal 0.27 (0.14–0.53) <0.001 0.44 (0.19–1.01) 0.053
Pre OP NePhRO
score
Low Reference
Intermediate 1.55 (0.94–2.56) 0.086
Pathologic T stage
T1a Reference
T1b-T3 1.20 (0.63–2.28) 0.576
BMI: body mass index, CKD: Chronic kidney disease, DM: diabetes mellitus, HTN:
hypertension, OP: operation; Pre OP: preoperative, Post OP: postoperative