UMIN-CTR Clinical Trial
| Unique ID issued by UMIN | UMIN000033936 |
|---|---|
| Receipt number | R000038703 |
| Scientific Title | A prospective nationwide survey of postoperative chronic pain following inguinal hernia repair in Japan |
| Date of disclosure of the study information | 2018/08/29 |
| Last modified on | 2026/02/08 15:58:20 |
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Basic information
Public title
A prospective nationwide survey of postoperative chronic pain following inguinal hernia repair in Japan
Acronym
Japanese nationwide survey of postoperative chronic pain following inguinal hernia repair
Scientific Title
A prospective nationwide survey of postoperative chronic pain following inguinal hernia repair in Japan
Scientific Title:Acronym
Japanese nationwide survey of postoperative chronic pain following inguinal hernia repair
Region
| Japan |
Condition
Condition
inguinal hernia
Classification by specialty
| Surgery in general |
Classification by malignancy
Others
Genomic information
NO
Objectives
Narrative objectives1
The aim of this prospective cohort study is to clarify the frequency of and risk factors for postoperative chronic pain at 3 months after inguinal hernia repair in Japan.
Basic objectives2
Others
Basic objectives -Others
Secondary endpoint is to investigate change over time of pain, collateral symptoms, and therapeutic course in patients with moderate or severe pain. Frequency of hernia recurrence, complication, and re-admission are also evaluated.
Trial characteristics_1
Exploratory
Trial characteristics_2
Others
Developmental phase
Not applicable
Assessment
Primary outcomes
Frequency of and risk factor for postoperative moderate or severe chronic pain (NRS 4 or more) at 3 months after inguinal hernia repair
Key secondary outcomes
1. Change over time of degree of chronic pain
2. Treatment details of postoperative chronic pain
3. Presence of a foreign body sensation, paresthesia, and sexual pain
4. Frequency of hernia recurrence, complication, and re-admission
Base
Study type
Observational
Study design
Basic design
Randomization
Randomization unit
Blinding
Control
Stratification
Dynamic allocation
Institution consideration
Blocking
Concealment
Intervention
No. of arms
Purpose of intervention
Type of intervention
Interventions/Control_1
Interventions/Control_2
Interventions/Control_3
Interventions/Control_4
Interventions/Control_5
Interventions/Control_6
Interventions/Control_7
Interventions/Control_8
Interventions/Control_9
Interventions/Control_10
Eligibility
Age-lower limit
| 20 | years-old | <= |
Age-upper limit
| Not applicable |
Gender
Male and Female
Key inclusion criteria
1. 20 years or more
2. Elective surgery for inguinal hernia
3. Patients who can have outpatient visit at 3 months after surgery
4. Patients who can make their own decision to participate this study
Key exclusion criteria
1. Emergent surgery
2. Surgery for relapse or chronic pain
3. Femoral hernia case
4. Patients who cannot express their pain
Target sample size
1600
Research contact person
Name of lead principal investigator
| 1st name | Masato |
| Middle name | |
| Last name | Narita |
Organization
National Hospital Organization Kyoto Medical Center
Division name
Department of Surgery
Zip code
642-8555
Address
1-1 Fukakusa-mukaihata-cho, Fushimi-ku 6128555 Kyoto city
TEL
+81756419161
narinari@kuhp.kyoto-u.ac.jp
Public contact
Name of contact person
| 1st name | Masato |
| Middle name | |
| Last name | Narita |
Organization
National Hospital Organization Kyoto Medical Center
Division name
Department of Surgery
Zip code
612-8555
Address
1-1 Fukakusa-mukaihata-cho, Fushimi-ku 6128555 Kyoto city
TEL
+81756419161
Homepage URL
hernia_study@kyotolan.hosp.go.jp
Sponsor or person
Institute
National Hospital Organization Kyoto Medical Center
Institute
Department
Personal name
Funding Source
Organization
National Hospital Organization
Organization
Division
Category of Funding Organization
Other
Nationality of Funding Organization
Japan
Other related organizations
Co-sponsor
Yonago medical center
Tsuruga medical center
Sendai medical center
Beppu medical center
Ureshino medical center
Fukuoka east medical center
Kyushu medical center
Osaka medical center
Kure medical center
Hakodate hospital
Takasaki medical center
Nagoya medical center
Himeji medical center
Kagoshima medical center
Osaka medical center
Tokyo medical center
Shiroyama hospital
JA Hiroshima General Hospital
Seirei Hamamatsu General Hospital
Osaka Rosai Hospital
Takamatsu Red Cross Hospital
Okayama Red Cross Hospital
Hiratsuka City Hospital
Name of secondary funder(s)
IRB Contact (For public release)
Organization
Ethical Committee of National Hospital Organization
Address
2-5-21 Higachigaoka, Meguro-ku, Tokyo
Tel
03-5712-507
700-kenkyu@mail.hosp.go.jp
Secondary IDs
Secondary IDs
NO
Study ID_1
Org. issuing International ID_1
Study ID_2
Org. issuing International ID_2
IND to MHLW
Institutions
Institutions
京都医療センター
米子医療センター
敦賀医療センター
仙台医療センター
別府医療センター
嬉野医療センター
福岡東医療センター
九州医療センター
大阪南医療センター
呉医療センター
函館病院
高崎総合医療センター
名古屋医療センター
姫路医療センター
鹿児島医療センター
大阪医療センター
東京医療センター
城山病院
JA広島総合病院
聖隷浜松病院
大阪労災病院
高松赤十字病院
岡山赤十字病院
平塚市民病院
Other administrative information
Date of disclosure of the study information
| 2018 | Year | 08 | Month | 29 | Day |
Related information
URL releasing protocol
chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://drive.usercontent.google.com/download?id
Publication of results
Unpublished
Result
URL related to results and publications
N/A
Number of participants that the trial has enrolled
2800
Results
A total of 2574 repairs (2233 patients; median age, 72 years; 92.8% male) were analyzed. The incidence of CPIP was 3.3% at 3 months and 2.4% at 2 years. Laparoscopic surgery significantly reduced the risk of CPIP at 2 years compared with open repair (OR, 0.49; 95% CI, 0.26-0.95; P = .03). In the laparoscopic group, mesh fixation with tackers, performed in 96.6% of cases, was the strongest independent predictor of CPIP at 2 years (OR >1,000,000; P < .001).
Results date posted
| 2025 | Year | 12 | Month | 29 | Day |
Results Delayed
Results Delay Reason
Date of the first journal publication of results
Baseline Characteristics
Laparoscopic repair, particularly transabdominal preperitoneal (TAPP) repair, was the most used procedures accounting for 53.3% of the total cases, followed by total extraperitoneal (TEP) (12.4%), Lichtenstein (11.9%), and mesh and plug repair (8.6%).
Participant flow
Between September 2018 and March 2021, two-thousand eight-hundred elective inguinal hernia repairs were planned and registered in the study population. Other than fifty-one patients who did not undergo surgery, 2749 repairs were performed. During surgery, fifty-four patients were excluded from the study population due to no inguinal hernia (n=49), and surgery for recurrent hernia (n=5). Nineteen patients withdrew their consent after surgery. A hundred and two patients did not visit the outpatient clinic at 3 months after surgery. Thus, a total of 2233 patients were operated on for 2574 hernia repairs, visited the outpatient clinic, and responded to the questionnaire 3 months after surgery. These patients were included in the analysis. During the study period, there were 39 patients who were included in the analysis but could not continue to participate in the study until the end for the following reasons: deceased by other causes (n=33), cognitive function decline (n=3), intracranial hemorrhage (n=1), cerebral infarction (n=1), and subdural hemorrhage (n=1). The questionnaires were retrieved from 2358, 2254, and 2142 cases 6 months, 1 year, and 2 years after surgery, respectively. Two thousand and nineteen patients responded to the entire questionnaires at all observation points.
Adverse events
Intraoperative complications occurred in 1.4% (37/2574) of cases, with peritoneal injury (n=11) and unexpected hemorrhage (n=9) being the most common (eTable 2). Postoperative complications within 90 days were reported in 10.1% (261/2574) of patients. Surgical site occurrences (SSOs) were significantly more frequent in the open surgery group (12.0%) than in the laparoscopic group (6.2%). Severe morbidity (Clavien-Dindo grade III) developed in 0.9% (23/2574) of the total population.
Outcome measures
The primary endpoints were as follows; 1) frequency of CPIP at 3 months, 6 months, 1 year, and 2 years after inguinal hernia repair, and 2) the risk factors for CPIP.
The secondary endpoints were as follows 1) the frequency of foreign body sensation, paresthesia, erection pain, ejaculation pain, recurrence at each observation point, 2) intraoperative and early postoperative complications, 3) identification of clinical factors influencing to worse NRS of pain at rest and daily activities in the laparoscopic and open surgery group at each observation point, and 4) an evaluation of what treatment was given for CPIP through questionnaire surveys.
Plan to share IPD
IPD sharing Plan description
Progress
Recruitment status
No longer recruiting
Date of protocol fixation
| 2018 | Year | 08 | Month | 28 | Day |
Date of IRB
| 2018 | Year | 08 | Month | 29 | Day |
Anticipated trial start date
| 2018 | Year | 08 | Month | 29 | Day |
Last follow-up date
| 2023 | Year | 04 | Month | 30 | Day |
Date of closure to data entry
| 2024 | Year | 12 | Month | 23 | Day |
Date trial data considered complete
| 2024 | Year | 12 | Month | 23 | Day |
Date analysis concluded
| 2025 | Year | 12 | Month | 31 | Day |
Other
Other related information
Primary endpoint
Frequency of and risk factor for postoperative moderate or severe chronic pain (NRS 4 or more) at 3 months after inguinal hernia repair
Secondary endpoint
1. Change over time of degree of chronic pain
2. Treatment details of postoperative chronic pain
3. Presence of a foreign body sensation, paresthesia, and sexual pain
4. Frequency of hernia recurrence, complication, and re-admission
Management information
Registered date
| 2018 | Year | 08 | Month | 29 | Day |
Last modified on
| 2026 | Year | 02 | Month | 08 | Day |
Link to view the page
Value
https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000038703
| Research Plan | |
|---|---|
| Registered date | File name |
| 2026/02/08 | H30-NHO外科-01_研究計画書.Vers.3.2.docx |
| Research case data specifications | |
|---|---|
| Registered date | File name |
| 2026/02/10 | Hernia Study_データーシート UMIN-IDCS 仕様書.xlsx |
| Research case data | |
|---|---|
| Registered date | File name |
| 2026/02/10 | Hernia Study_データーシート UMIN-IDCS登録用.xlsx |
Single case data URL
Value
https://center6.umin.ac.jp/ice/38703
