Incidence of postoperative complications in transabdominal preperitoneal repair for groin hernia is influenced by poor performance status rather than by old age

Abstract Aim The present study was designed to evaluate the safety and feasibility of transabdominal preperitoneal (TAPP) repair for very old patients with groin hernia and to identify the risk factors predicting perioperative complications. Methods A total of 140 patients treated by TAPP were reviewed retrospectively. They were divided into two groups: patients ≥80 years of age (≥80 years group; n = 26) and those <80 years of age (<80 years group; n = 114). Patient characteristics and surgical outcomes were then statistically compared between the two groups. Results Number of patients with any comorbidities was significantly higher in the ≥80 years group than in the <80 years group (96.2% vs 61.4%, P = 0.003). There were no significant differences in surgical outcomes between the two groups. In the univariate analysis of perioperative complications, poor performance status (PS) (P = 0.014), lower hemoglobin level (P = 0.038) and lower albumin level (P = 0.016) were significantly associated with the occurrence of postoperative complications, and multivariate analysis showed that only poor PS was an independent factor (PS 0‐2 vs 3‐4: P = 0.034, OR 5.192 [95% CI; 1.137 to 23.71]). Conclusions This is the first report to show that the incidence of postoperative complications in TAPP repair for groin hernia is influenced by poor PS rather than old age. TAPP can be a safe surgical procedure for very old patients with a good PS, with benefits that are equal to those in young patients.

to work than open hernia surgery (OHS). [3][4][5] However, LHS requires general anesthesia and a longer operation time than OHS. In addition, LHS has a higher incidence of postoperative complications than OHS, and TAPP, in particular, seems to be associated with serious complications, such as port-site hernia and visceral injury. 3,6,7 Based on these findings, current guidelines recommend LHS as an option for the treatment of primary unilateral groin hernia when carried out by a sufficiently experienced surgeon. 8,9 Because the incidence of groin hernia is higher in the elderly than in younger individuals due to the weakening of tissue with age, 1,10-12 the number of groin hernia surgeries for elderly patients is expected to increase as the population progressively ages in developed countries. Furthermore, postoperative morbidity and mortality rates in major surgery are also higher in elderly patients than in young patients. [13][14][15] Elderly patients often receive many medications and have multiple comorbidities and histories of laparotomy that can hamper laparoscopic surgery. Therefore, older age may be a risk factor predicting postoperative complications in LHS. Several studies have reported comparable outcomes between LHS and OHS in elderly patients; [16][17][18] however, whether older age influences the incidence of postoperative complications in LHS has been unclear.
Therefore, objective parameters regarding the selection of laparoscopic surgery for elderly groin hernia patients are needed.
The purpose of the present study was to evaluate the safety and feasibility of TAPP repair for very old patients with groin hernia and to identify the risk factors predicting postoperative complications in this population.

| PATIENTS AND ME THODS
From September 2011 to May 2016, 163 patients underwent groin hernia repair at Saga University Hospital. During this period, almost all groin hernia patients were treated by TAPP repair when the patient's condition allowed for laparoscopic surgery under general anesthesia.
Among 163 groin hernia patients, 20 were treated by OHS, whereas the remaining 143 were treated by TAPP. Selection criteria for OHS were as follows: contraindication for general anesthesia as a result of severe comorbidities (n = 4); severe intra-abdominal adhesion as a result of multiple laparotomies (n = 6); and emergency cases as a result of intestinal obstruction and/or necrosis (n = 10). Furthermore, among 143 patients who underwent TAPP, three who received additional surgery at the same time were excepted. Therefore, this study retrospectively reviewed 140 consecutive groin hernia patients who received TAPP. These 140 patients were divided into two groups: patients ≥80 years of age (≥80 years group; n = 26) and those <80 years of age (<80 years group; n = 114) ( Figure 1). Patient characteristics and surgical outcomes including operation time, blood loss, hospital stay and postoperative complications were statistically compared between the two groups. Details of comorbidity are as follows: pulmonary dysfunction was defined as % vital capacity (%VC) ≤80% or forced expiratory volume in 1-second (FEV1.0%) ≤70%; renal dysfunction was defined as estimated glomerular filtration rate (eGFR) ≤60 mL/min. Circulatory disease included myocardial infarction, arrhythmia and valvular heart disease. Postoperative complications were classified according to the Clavien-Dindo classification of surgical complications, 19 and complications classified as grade 2 or higher were reviewed.

| Statistical analyses
Data analyses were carried out using JMP Pro 13 (SAS Institute Inc., Cary, NC, USA) statistical software. All data are expressed as mean ± standard deviation. Fisher's exact test or a two-tailed Student's t-test was used to evaluate group differences. Variables with P values ≤0.05 on univariate analysis were included in a multivariate logistic regression model. All P values <0.05 were accepted as statistically significant. type of groin hernia and size of hernia orifice were similar between the two groups. Lower hemoglobin (Hb) (12.8 ± 1.6 mg/ dL vs 13.7 ± 2.7 mg/dL, P = 0.038) and albumin (Alb) levels (3.7 ± 0.4 mg/dL vs 4.0 ± 0.5 mg/dL, P = 0.016) were observed in the ≥80 years group. No significant differences regarding the proportions of emergency operations, recurrent cases and the histories of laparotomy, prostatectomy, antithrombotic therapy and steroid therapy were observed between the two groups. The proportion of patients with any comorbidities (96.2% vs 61.4%, P = 0.003), especially those having renal dysfunction (57.8% vs 20.2%, P = 0.003), pulmonary dysfunction (%VC ≤80% or FEV1.0% ≤70%) (53.9% vs 15.8%, P < 0.001), and cerebrovascular infarction (23.1% vs 3.5%, P = 0.003) was significantly higher in the ≥80 years group than in the <80 years group. It is noteworthy that over 95% of the patients in the ≥80 years group had some comorbidities. The proportion of patients with comorbidities of circulatory disease, liver disease, diabetes, and dementia did not differ to a statistically significant extent.

| Surgical outcomes and perioperative complications of TAPP
Surgical outcomes and perioperative complications of TAPP repair were compared between the ≥80 and <80 years groups (Table 2).
There were no significant differences in the respective surgical outcomes between the ≥80 and <80 years groups, including opera- were no significant differences in the rates of both intraoperative complications (0% vs 0.9%, P = 1.000) and postoperative complications (34.6% vs 18.4%, P = 0.109). Although the incidence of hematoma was significantly higher in the ≥80 years group (11.5% vs 0%, P = 0.006), the incidences of other complications, such as seroma, wound infection and visceral injury, were similar between the two groups. There were no mortalities in either group. Pain and/or discomfort that lasted more than 1 month after surgery was more frequent in the <80 years group, although not to a statistically significant degree (0% vs 6.1%, P = 0.348).

| Identification of risk factors predicting perioperative complications of TAPP
Univariate and multivariate analyses regarding the perioperative complications of TAPP repair are shown in Table 3. In the univariate analysis, poor PS was significantly associated with the occur-

| D ISCUSS I ON
Groin hernia repair is one of the most common surgical procedures carried out worldwide. 19 According to a population-based study by In the present study, there were no patients with chronic postoperative inguinal pain requiring long-term follow up or drug treatment. However, there was a tendency for young people to feel postoperative inguinal pain or discomfort in the first month after surgery, although there was no significant difference. Young age was regarded as a risk factor for postoperative pain in previous reports; however, these reports were mainly based on research on OHS. 28,29 In reports on LHS, some studies noted that age did not have a significant influence on postoperative inguinal pain; 30,31 however, this point remains controversial.
The major limitations of the present study are its retrospective design and small sample size. In addition, many surgeons from resident to expert carried out operations in this study. The preoperative complication rate did not differ between procedures carried out by residents and experts; however, experts may have carried out more difficult operations such as hernia after total prostatectomy, recurrent hernia, and hernia of high-risk patients including the very elderly.

| CON CLUS ION
The present study for the first time showed that the incidence of perioperative complications in TAPP repair for groin hernia is influenced by poor PS rather than old age. In conclusion, when the condition of the patient allows general anesthesia and PS is 0-2, TAPP can be one of the optimal surgical procedures even for very elderly patients over 80 years of age, as it is for young patients. Very elderly patients with a good PS can enjoy the benefits of TAPP equally to young people.

D I SCLOS U R E
This study was carried out in agreement with the guidelines of the institutional ethics committee and was conducted in accordance with the Declaration of Helsinki.
Conflicts of Interest: Authors declare no conflicts of interest for this article.