Obesity does not increase mortality after emergency surgery

Debunking the "Obesity Paradox": Obesity is Associated With Adverse Outcomes in Emergency General Surgery

INTRODUCTION

Obesity is increasingly prevalent both nationwide and in the emergency general surgery (EGS) population. While previous studies have shown that obesity may be protective against mortality following EGS procedures, the association between body mass index (BMI) and postoperative outcomes, as well as intraoperative decision-making, remains understudied.

METHODS

The National Surgical Quality Improvement Program 2015-2019 database was used to identify all adult patients undergoing an open abdominal or abdominal wall procedure for EGS conditions. Our outcomes included 30-d postoperative mortality, composite 30-d morbidity, delayed fascial closure, reoperation, operative time, and hospital length of stay (LOS). Multivariable logistic regression models were used to explore the association between BMI and each outcome of interest while adjusting for patient demographics, comorbidities, laboratory tests, preoperative and intraoperative variables.

RESULTS

We identified 78,578 patients, of which 3121 (4%) were categorized as underweight, 23,661 (30.1%) as normal weight, 22,072 (28.1%) as overweight, 14,287 (18.2%) with class I obesity, 7370 (9.4%) with class II obesity, and 8067 (10.3%) with class III obesity. Class III obesity was identified as a risk factor for 30-d postoperative morbidity (adjusted odds ratio 1.14, 95% CI, 1.03-1.26, P < 0.01). An increase in obesity class was also associated with a stepwise increase in the risk of undergoing delayed fascial closure, experiencing a prolonged operative time, and having an extended LOS.

CONCLUSIONS

Obesity class was associated with an increase in delayed fascial closure, longer operative time, higher reoperation rates, and extended hospital LOS. Further studies are needed to explore how a patient's BMI impacts intraoperative factors, influences surgical decision-making, and contributes to hospital costs.

Association of High BMI With Morbidity and Mortality in Common Emergency General Surgery Procedures

INTRODUCTION

Emergency general surgery (EGS) patients are at increased risk for postoperative morbidity and mortality. Obesity is a risk factor for poor outcomes in this population. Our study aimed to explore the association of body mass index (BMI) with postoperative outcomes in patients requiring common EGS procedures.

METHODS

A retrospective review of the 2018-2020 National Surgical Quality Improvement Program database identified patients undergoing four common EGS procedures: large bowel resection, small bowel resection, cholecystectomy, and appendectomy. Patients were classified by BMI: normal weight (18.5-24.9 kg/m2), obesity classes I (30-34.9 kg/m2), II (35-39.9 kg/m2), III (40-49.9 kg/m2), and IV (≥50 kg/m2). Main outcomes of interest were major adverse event (MAE) and mortality.

RESULTS

From 2018 to 2020, a total of 82,540 patients underwent one of four common EGS procedures. On unadjusted analysis, obesity class IV had higher mortality rates compared to classes I-III (6.2% vs 3.1%, P < 0.001). Patients in obesity classes I-III had lower odds of MAE and death relative to those of normal weight. Compared to other patients with obesity, those in obesity class IV were at increased risk of MAE (odds ratio 1.27; 95% confidence interval 1.13-1.44) and death (odds ratio 1.69; 95% confidence interval 1.34-2.13).

CONCLUSIONS

Patients with varying degrees of obesity have different risk profiles following common EGS procedures. While patients in lower obesity classes had reduced odds of adverse outcomes, those with BMI ≥50 kg/m2 were particularly at greater risk for postoperative morbidity and mortality. This vulnerable population warrants further investigation and increased vigilance to ensure high-quality care.

High Body Mass Index is Associated With Increased Risk of Complications After Emergency Ventral Hernia Repair

INTRODUCTION

Emergency general surgery is a risk factor for postoperative morbidity and mortality. Patients with obesity are at greater risk for complications following ventral hernia repair (VHR). Our study aimed to determine the association of obesity with postoperative outcomes in patients requiring emergency VHR.

METHODS

Our retrospective study used the 2016-2020 National Surgical Quality Improvement Program database to identify patients undergoing emergency VHR. Patients were classified by body mass index (BMI): normal weight 18.5-24.9 kg/m2, overweight 25-29.9 kg/m2, obesity 30-39.9 kg/m2, morbid obesity 40-49.9 kg/m2, and super morbid obesity (SMO) ≥50 kg/m2. The primary outcome of interest was surgical site infection (SSI).

RESULTS

From 2016 to 2020, a total 11,593 patients underwent emergency VHR. Patients with higher BMI had increased incidences of postoperative complications. Compared to other patients with obesity, SMO patients had higher rates of SSI (11.5% versus 5.5%, P < 0.001), prolonged ventilatory support (4.0% versus 1.5%, P < 0.001), length of stay ≥4 d (52.7% versus 42.2%, P < 0.001), reoperation (6.4% versus 3.4%, P < 0.001), and readmission (11.3% versus 7.2%, P < 0.001). Super morbid obesity (SMO) patients had increased odds of SSI (odds ratio [OR] 5.55, 95% confidence interval [CI] 3.47-8.88), prolonged ventilatory support (OR 1.92, 95% CI 1.07-3.45), and reoperation (OR 1.97, 95% CI 1.26-3.09) compared to normal weight patients.

CONCLUSIONS

Patients with BMI ≥50 kg/m2 undergoing emergency VHR have increased overall incidences of SSIs, prolonged mechanical ventilation, reoperation, and readmission, and this remains significant when compared to other patients with obesity. This population is at significant risk for postoperative morbidity, and increased vigilance in perioperative management is imperative to ensure safe, high-quality care.

Effect of obesity on perioperative outcomes following gastrointestinal surgery: meta-analysis

BACKGROUND

Obesity can pose perioperative challenges related to obesity-associated co-morbidities and technical factors. However, the true impact of obesity on postoperative outcomes is not well established and reports are conflicting. The aim was to perform a systematic review and meta-analysis to explore the effect of obesity on perioperative outcomes for general surgery procedures in distinct obesity subtypes.

METHODS

A systematic review was performed for studies reporting postoperative outcomes in relation to BMI in upper gastrointestinal, hepatobiliary and colorectal based on an electronic search using the Cochrane Library, Science Direct, PubMed and Embase up to January 2022. The primary outcome was the incidence of 30-day postoperative mortality among patients with obesity undergoing general surgical procedures in comparison to patients with normal range BMI.

RESULTS

Sixty-two studies, including 1 886 326 patients, were eligible for inclusion. Overall, patients with obesity (including class I/II/II) had lower 30-day mortality rates in comparison to patients with a normal BMI (odds ratio (OR) 0.75, 95 per cent c.i. 0.66 to 0.86, P < 0.0001, I2 = 71 per cent); this was also observed specifically in emergency general surgery (OR 0.83, 95 per cent c.i. 0.79 to 0.87, P < 0.0000001, I2 = 7 per cent). Compared with normal BMI, obesity was positively associated with an increased risk of 30-day postoperative morbidity (OR 1.11, 95 per cent c.i. 1.04 to 1.19, P = 0.002, I2 = 85 per cent). However, there was no significant difference in postoperative morbidity rates between the cohorts of patients with a normal BMI and class I/II obesity (OR 0.98, 95 per cent c.i. 0.92 to 1.04, P = 0.542, I2 = 92 per cent). Overall, the cohort with obesity had a higher rate of postoperative wound infections compared with the non-obese group (OR 1.40, 95 per cent c.i. 1.24 to 1.59, P < 0.0001, I2 = 82 per cent).

CONCLUSION

These data suggest a possible 'obesity paradox' and challenge the assumption that patients with obesity have higher postoperative mortality compared with patients with normal range BMI. Increased BMI alone is not associated with increased perioperative mortality in general surgery, highlighting the importance of more accurate body composition assessment, such as computed tomography anthropometrics, to support perioperative risk stratification and decision-making.

REGISTRATION NUMBER

CRD42022337442 (PROSPERO https://www.crd.york.ac.uk/prospero/).

Surgical treatment of digestive cancer in a well-defined elderly population

INTRODUCTION

Digestive cancer is of concern because of its frequency and severity with an increasing older median age of onset. The purpose of this study was to describe in a well-defined population presenting with non-metastatic digestive cancer the frequency of surgical resection and outcomes according to age.

PATIENTS AND METHODS

We analyzed 7760 patients with a non-metastatic digestive cancer, recorded in the Burgundy population-based digestive cancer registry between 2009 and 2017. There were 3506 non-colorectal cancers and 4254 colorectal cancers with 3292 colon and 962 rectal cancers. The frequency of surgical resection was analyzed according to age (classified into four categories <70, [70-80[, [80-85[, and ≥85), sex, comorbidities and obesity. Postoperative mortality at 30 and 90 days was determined according to age, sex, comorbidity, obesity, location, surgery R0 or not. The 5-year survival study included 2952 patients with colorectal cancer, non-metastatic and who benefited from an R0 resection.

RESULTS

Overall, 64% of the patients with M0 digestive cancer underwent a surgical resection, varying from 31% for Non colorectal Digestive cancers to 94% for colon site. The percentage of patients operated on for a resectable disease decreases from 71% before age 70 to 43% from age 85. Age and comorbidities were the main criteria influencing the probability of resection. At 30 days, postoperative mortality was 3%, all localizations and ages combined. At 90 days, this rate was 5%. In patients over 85 years old it gradually increases from 7% at 30 days and to 10% at 90 days. A man under 70 years of age has a net survival of 0.88 at 5 years, and 0.91 for a woman. For a man between 70 and 80 years old, it decreases to 0.81 and to 0.66 from 80 years old. In women, net survival is 0.87 between 70 and 80 years of age at 5 years, then drops to 0.75 from age 80.

CONCLUSION

Our study shows a drop in access to surgery at different pivotal ages depending on the tumor location. This sudden drop in the resection rate is not justified by the increase in mortality with age, which is linear. In addition, the expected benefits of surgery are significant, with a net survival, mainly after the 1st year, of the same order as for younger patients. Age by itself should not be the only criterion in the medical decision. The challenge is to detect and treat the comorbidities that worsen the operative risk and the prognosis. There are few data on the management of digestive cancers specifically in the elderly. Our study shows that access to surgery is strongly linked to age and this in a non-linear way, whereas the expected benefits of surgery are significant, of the same order as for younger patients. Age itself should not be the only criterion in the medical decision.

The impact of obesity on surgical outcomes in patients undergoing emergency laparotomy for high-risk abdominal emergencies

BACKGROUND

Obesity has been shown to increase the rates of morbidity and occasionally mortality in patients undergoing nonbariatric elective surgery. However, little is known about the impact of obesity on outcomes after surgery for high-risk abdominal emergencies.

METHODS

A single-center retrospective evaluation of outcomes in high-risk abdominal emergency patients categorized by body mass index (BMI) was conducted. Patient demographics, comorbidities, and operative details were analyzed. Patients with normal weight (BMI 18.5-24.9) served as comparators. Multivariable linear and logistic regression analyses were performed to assess the impact of obesity on surgical outcomes.

RESULTS

In total, 886 patients with BMI < 18.5 (underweight; n = 50), 18.5-24.9 (normal weight; n = 306), 25-29.9 (overweight; n = 336) and ≥ 30 (obese; n = 194) based on the World Health Organization (WHO) weight classification criteria met the inclusion criteria. Compared to normal-weight patients, patients with overweight and obesity were older and more likely to be male. The rates of comorbidity (100% vs 91.2%, p =  < 0.0001), morbidity (77.8% vs 65.6%, p = 0.003), and in-hospital mortality (44.8% vs 30.4%, p = 0.001) were all higher in patients with obesity than in normal-weight patients. Patients with obesity had an increased intensive care unit length of stay (ICU LOS) (13 days vs 9 days, p = 0.019) and hospital LOS (21.4 days vs 18.1 days, p = 0.081) and prolonged ventilation (39.1% vs 19.6%, p = 0.003). As BMI deviated from the normal range, the morbidity and mortality rates increased incrementally, with the highest morbidity (87.9%) and mortality (54.5%) rates observed in morbidly obese patients (BMI ≥ 40).

CONCLUSIONS

Patients with obesity were the most likely to have coexisting conditions, experience postoperative complications, and die during the first admission following EL for high-risk abdominal emergencies.

The Obesity Paradox in Emergency General Surgery Patients

Operative management of emergency general surgery (EGS) diagnoses involves a range of procedures which can carry high morbidity and mortality. Little is known about the impact of obesity on patient outcomes. The aim of this study was to examine the association between body mass index (BMI) >30 kg/m² and mortality for EGS patients. We hypothesized that obese patients would have increased mortality rates.

A regional integrated health system EGS registry derived from The American Association for the Surgery of Trauma EGS ICD-9 codes was analyzed from January 2013 to October 2015. Patients were stratified into BMI categories based on WHO classifications. The primary outcome was 30-day mortality. Longer-term mortality with linkage to the Social Security Death Index was also examined. Univariate and multivariable analyses were performed.

A total of 60 604 encounters were identified and 7183 (11.9%) underwent operative intervention. Patient characteristics include 53% women, mean age 58.2 ± 18.7 years, 64.2% >BMI 30 kg/m², 30.2% with chronic obstructive pulmonary disease, 19% with congestive heart failure, and 31.1% with diabetes. The most common procedure was laparoscopic cholecystectomy (36.4%). Overall, 90-day mortality was 10.9%. In multivariable analysis, all classes of obesity were protective against mortality compared to normal BMI. Underweight patients had increased risk of inpatient (OR = 1.9, CI = 1.7-2.3), 30-day (OR = 1.9, CI = 1.7-2.1), 90-day (OR = 1.8, CI 1.6-2.0), 1-year (OR = 1.8, CI = 1.7-2.0), and 3-year mortality (OR = 1.7, CI = 1.6-1.9).

When stratified by BMI, underweight EGS patients have the highest odds of death. Paradoxically, obesity appears protective against death, even when controlling for potentially confounding factors. Increased rates of nonoperative management in the obese population may impact these findings.

The Effect of Bariatric Surgery Volume on General Surgery Outcomes for Morbidly Obese Patients

INTRODUCTION

Bariatric surgery performed at high volume centers decreases length of stay, cost, and morbidity and mortality. The effect of a high volume of bariatric surgery procedures on outcomes may extend not just to bariatric surgery but to any general surgical procedure in morbidly obese patients. We hypothesized that patients with morbid obesity (body mass index >40 kg/m²) undergoing common, nonbariatric general surgery would have decreased morbidity and mortality at centers performing high volumes of bariatric surgery.

METHODS

The 2016 National Inpatient Sample (NIS) was used to identify the number of laparoscopic gastric bypass and sleeve gastrectomy performed at each hospital. Hospitals were classified as high volume bariatric hospitals (HVBH) ≥10 reported cases (50 actual)/year or low volume bariatric hospitals (LVBH) <10 reported cases (50 actual)/year, as NIS reports a 20% sample of actual cases. Patients with morbid obesity undergoing laparoscopic or open appendectomy, cholecystectomy, or ventral hernia repair were included for analysis. Propensity scores were developed based on available demographics, comorbidities, and hospital procedure volume. Postoperative complications during the index hospital admission, determined by ICD-10 code, were compared using inverse propensity weights. Differences were considered significant with a p value of <0.05.

RESULTS

The total number of general surgery patient cases analyzed was 14,028 from 2,482 hospitals, representing 70,140 admissions. The cohort of patients undergoing operations treated at HVBH were younger (p=0.03) with higher rates of COPD (p=0.04). Patients at LVBH had higher rates of nicotine dependence (p=0.0001) and obstructive sleep apnea (p < 0.001). On propensity-weighted analysis adjusting for preoperative comorbidities and hospital procedure volume, there were significantly higher rates of multiple postprocedure complications at LVBH, specifically, postprocedure respiratory failure for patients undergoing elective laparoscopic cholecystectomy, elective ventral hernia repair with mesh and appendectomy.

CONCLUSION

Patients with morbid obesity may have an advantage in having general surgery procedures at HVBH. HVBH may have a volume-outcomes relationship where the hospital and staff familiarity with the management principles required to minimize the postoperative risk associated with morbid obesity and improve patient outcomes.

Exploring the role of obesity and overweight in predicting postoperative outcome of abdominal surgery in a sub-Saharan African setting: a prospective cohort study

Objective

Current literature on the role of excess weight in predicting surgical outcome is controversial. In sub-Saharan Africa, there is extreme paucity of data regarding this issue in spite of the increasing rates of obesity and overweight in the region. This prospective cohort study, carried out over a period of 4 months at Limbe Regional Hospital in the Southwest region of Cameroon, assessed 30-day postoperative outcome of abdominal surgery among consecutive adults with body mass index (BMI) ≥ 25 kg/m². Adverse postoperative events were reported as per Clavien–Dindo classification.

Results

A total of 103 patients were enrolled. Of these, 68.9% were female. The mean age was 38.2 ± 13.7 years. Sixty-four (62.1%) of the patients were overweight and the mean BMI was 29.2 ±4.3 kg/m². The physical status scores of the patients were either I or II. Appendectomy, myomectomy and hernia repair were the most performed procedures. The overall complication rate was 13/103 (12.6%), with 61.5% being Clavien–Dindo grades II or higher. From the lowest to the highest BMI category, there was a significant increase in the proportion of patients with complications; 25–29.9 kg/m²: 6.25%, 30–34.9 kg/m²: 18.75%, 35–39.9 kg/m²: 25.0%, and ≥ 40 kg/m²: 66.70%; p = 0.0086.

The Role of Obesity in Sepsis Outcome among Critically Ill Patients: A Retrospective Cohort Analysis

Background. The objective of this study was to assess the correlation between sepsis, obesity, and mortality of patients admitted to an Intensive Care Unit (ICU). Subjects and Methods. Data of all patients admitted to the ICU of a tertiary hospital during a 28-month period were retrospectively analyzed and included in the study. Results. Of 834 patients included, 163 (19.5%) were obese, while 25 (3.0%) were morbidly obese. Number of comorbidities (P < 0.001), bloodstream infection (P  0.033), and carbapenemase-producing Klebsiella pneumoniae colonization during ICU stay (P  0.005) were significantly associated with obesity, while nonobese patients suffered more frequently from spontaneous intracranial hemorrhage (P  0.038). Total ICU mortality was 22.5%. Increased mortality among obese ICU patients was observed. Sepsis was the main condition of admission for which obese patients had statistically lower survival than normal weight subjects (76.3% versus 43.7%; P  0.001). Mortality of septic patients upon admission was independently associated with SOFA score upon ICU admission (P  0.003), obesity (P  0.014), pneumonia (P  0.038), and development of septic shock (P  0.015). Conclusions. Our study revealed that sepsis upon ICU admission is adversely influenced by obesity but further studies are needed in order to assess the role of obesity in sepsis outcome.

Obese motorcycle riders have a different injury pattern and longer hospital length of stay than the normal-weight patients

Background

The adverse effects of obesity on the physical health have been extensively studied in the general population, but not in motorcycle riders (includes both drivers and pillions). The aim of this study was to compare injury patterns, injury severities, mortality rates, and in-hospital or intensive care unit (ICU) length of stay (LOS) between obese and normal-weight patients who were hospitalized for the treatment of trauma following motorcycle accidents in a level I trauma center.

Methods

Detailed data of 466 obese adult patients with a body mass index (BMI) ≥30 kg/m² and 2701 normal-weight patients (25 > BMI ≥18.5 kg/m²) who had sustained motorcycle accident-related injuries were retrieved from the Trauma Registry System between January 1, 2009 and December 31, 2013. We used the Pearson’s chi-squared test, Fisher’s exact test, and independent Student’s t-test to analyze differences between the two groups.

Results

Compared to normal-weight motorcycle riders, more obese riders were men and drivers as opposed to pillions. In addition, fewer obese motorcycle riders showed alcohol intoxication. Analyses of the patients’ Abbreviated Injury Scale (AIS) scores revealed that obese motorcycle riders presented with a higher rate of injury to the thorax, but a lower rate of injury to the face than normal-weight patients. In addition, obese motorcycle riders had a 2.7-fold greater incidence of humeral, 1.9-fold greater incidence of pelvic, and 1.5-fold greater incidence of rib fractures. In contrast, normal-weight motorcycle riders sustained a significantly higher rate of maxillary and clavicle fractures. Obese motorcycle riders had a significant longer in-hospital LOS than normal-weight motorcycle riders did (10.6 days vs. 9.5 days, respectively; p = 0.044), with an increase in in-hospital LOS of 0.82 days associated with every 10-unit increase in BMI. No statistically significant differences in Injury Severity Score (ISS), New Injury Severity Score (NISS), Trauma-Injury Severity Score (TRISS), mortality, percentage of patients admitted to the ICU, or LOS in the ICU were found between obese and normal-weight patients.

Discussion

No differences of injury severity, mortality, and LOS in the ICU between obese and normal-weight motorcycle riders in this study may be partly attributed to the motorcycle injuries occur at relatively low velocity, considering that the riding of majority of motorcycles are forbidden on highways in Taiwan and that most traffic accidents occur in relatively crowded streets.

Conclusion

Obese motorcycle riders had different injury characteristics and bodily injury patterns than normal-weight motorcycle riders. Moreover, they had a longer in-hospital LOS; this was particularly true for those with pelvic fractures. However, injury severity and mortality were not significantly different between the two groups.

Traumatic injuries among adult obese patients in southern Taiwan: a cross-sectional study based on a trauma registry system

BACKGROUND

The adverse impact of obesity has been extensively studied in the general population; however, the added risk of obesity on trauma-related mortality remains controversial. This study investigated and compared mortality as well injury patterns and length of stay (LOS) in obese and normal-weight patients hospitalized for trauma in the hospital and intensive care unit (ICU) of a Level I trauma center in southern Taiwan.

METHODS

Detailed data of 880 obese adult patients with body mass index (BMI) ≥ 30 kg/m(2) and 5391 normal-weight adult patients (25 > BMI ≥ 18.5 kg/m(2)) who had sustained a trauma injury between January 1, 2009 and December 31, 2013 were retrieved from the Trauma Registry System. Pearson's chi-squared, Fisher's exact, and independent Student's t-tests were used to compare differences between groups. Propensity score matching with logistic regression was used to evaluate the effect of obesity on mortality.

RESULTS

In this study, obese patients were more often men, motorcycle riders and pedestrians, and had a lower proportion of alcohol intoxication compared to normal-weight patients. Analysis of Abbreviated Injury Scale scores revealed that obese trauma patients presented with a higher rate of injury to the thorax, but a lower rate of facial injuries than normal-weight patients. No significant differences were found between obese and normal-weight patients regarding Injury Severity Score (ISS), Trauma-Injury Severity Score (TRISS), mortality, the proportion of patients admitted to the ICU, or LOS in ICU. After propensity score matching, logistic regression of 66 well-matched pairs did not show a significant influence of obesity on mortality (odds ratio: 1.51, 95% confidence interval: 0.54-4.23 p = 0.438). However, significantly longer hospital LOS (10.6 vs. 9.5 days, respectively, p = 0.044) was observed in obese patients than in normal-weight patients, particularly obese patients with pelvic, tibial, or fibular fractures.

CONCLUSION

Compared to normal-weight patients, obese patients presented with different injury characteristics and bodily injury patterns but no difference in mortality.

Obesity in critically ill patients is associated with increased need of mechanical ventilation but not with mortality

Worldwide incidence of obesity is increasing and impaired outcome in postoperative patients has been described. Antibiotic prescribing is complicated by different pharmacology in this population. This study evaluates mortality and morbidity of obese postoperative patients and explores possible relation to antibiotic therapy. Therefore, data obtained in a prospective study in 2009-2010 were analysed. Postoperative patients on 5 ICUs were included with >48h of ICU treatment and documented body-mass-index (BMI). Altogether 451 non-obese patients (BMI<30kg/m(2)) were compared with 130 obese patients including propensity score matching. There was significant heterogeneity of baseline characteristics. ICU-mortality was 7.5% in non-obese and 7.7% in obese patients (p>0.999), but 65.4% of obese patients required mechanical ventilation compared with only 53.2% of non-obese patients (p=0.016). These findings were validated in multivariate regression analyses (adjusted OR for ICU-mortality for obese patients 0.53, 95%-CI 0.188-1.321, p=0.197; adjusted OR for mechanical ventilation 1.841, 95%-CI 1.113-3.076, p=0.018). Results were confirmed by propensity score matching. Therapeutic drug monitoring for vancomycin (TDM) showed that underdosing and overdosing occurred more often in obese patients and sufficient TDM levels were less often achieved. In conclusion, obesity is associated with increased morbidity but ICU mortality is equal compared with a non-obese population. Pharmacological differences might explain observed differences in antibiotic therapy and in obese patients TDM might be especially of importance.