Predictive factors of mortality in bariatric surgery: Data from the Nationwide Inpatient Sample

doi:10.1016/j.surg.2011.05.020

Surgery

Volume 150, Issue 2, August 2011, Pages 347-351

Presented at the Academic Surgical Congress on February 2, 2011, Huntington Beach, CA.

https://doi.org/10.1016/j.surg.2011.05.020 Get rights and content

Background

Understanding predictors of mortality in bariatric surgery enables surgeons to use these factors for analysis of risk-adjusted mortality and aids in the surgical decision making and informed consent process.

Objectives

To evaluate the effect of patient characteristics (age, gender, race, and payer type), preoperative comorbidities, and operative technique (laparoscopic versus open, gastric bypass versus gastric band) on mortality in patients who underwent bariatric operations.

Methods

Using the National Inpatient Sample database, clinical data of patients with morbid obesity who underwent bariatric surgery from 2006 to 2008 were examined. Multivariate logistic regression analyses were performed to identify independent predictors of in-hospital mortality.

Results

A total 304,515 patients underwent bariatric surgery over the 3-year period. The majority of patients were female (80%) and Caucasian (74%). Their mean age was 44 years and 31.6% were >50 years old. The most common payer type was private (73.5%). Laparoscopic approach was utilized in 86.2% of cases. The overall in-hospital mortality was 0.12%. Using multivariate regression analysis, male gender (adjusted odds ratio [AOR], 1.7), age >50 years (AOR, 3.8), congestive heart failure (AOR, 9.5), peripheral vascular disease (AOR, 7.4), chronic renal failure (AOR, 2.7), open procedure (AOR, 5.5), and gastric bypass operation (AOR, 1.6) were factors associated with greater mortality. Ethnicity, hypertension, diabetes, liver disease, chronic lung disease, sleep apnea, alcohol abuse, and payer type had no association with mortality in this study.

Conclusion

Modifiable risk factors predictive of mortality include open surgery and gastric bypass procedure; nonmodifiable risk factors include older age, male gender, and a history of congestive heart failure, peripheral vascular disease, and chronic renal failure. Surgeons should consider these factors in selection of patients to undergo bariatric operations, providing informed consent, and selection of the procedural type.

Section snippets

Methods

Using the NIS database from 2006 to 2008, we analyzed morbidly obese patients who underwent bariatric operations. The NIS is the largest inpatient care database in the United States; approximately 1,000 hospitals participate, and it contains information from nearly 8 million hospital stays each year. The NIS is composed of a nationally representative sample of approximately 20% of US community hospitals, resulting in a sampling frame that comprises approximately 90% of all hospital discharges

Results

A total of 304,515 patients underwent bariatric surgery during the 3-year period. Characteristics of these patients are listed in Table I. The proportion of females was 80%, and Caucasians was 74%. The mean age of the patient population was 44 years with 31.6% of patients >50 years old. The most prevalent comorbidities were hypertension (54.5%), diabetes (29.7%), chronic lung disease (18.3%), sleep apnea (15.7%), and liver disease (8.8%). The most common payer type was private insurance,

Discussion

This report with in-hospital data from a large number of patients who underwent bariatric surgery between 2006 and 2008 showed a low overall in-hospital mortality of 0.12%, which is much less than the reported in-hospital mortality of 0.8% in 1998.⁵ The reasons for the improved mortality are probably multifactorial, but possibly reflect the increased number of cases being performed in the United States, the wide adoption of the laparoscopic approach, development of fellowship training programs,

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Obesity is an independent risk factor for heart failure in patients with hypertrophic cardiomyopathy (HC). In this study, we examined national trends and early outcomes of bariatric surgery for obesity in patients with HC. Using the weighted discharge data from the National Inpatient Sample, we identified adult patients with HC who underwent elective bariatric surgery for obesity between 2011 and 2017. A total of 443 obese patients with HC were identified, and 42% (n = 185) had obstructive HC. The annual number of patients increased from 18 in 2011 to 130 in 2017. Overall, the median (interquartile range) age was 50 (43 to 57) years, and 85 patients (19%) were 60 years or older. Approximately 20% (n = 90) of the patients had heart failure at the time of operation. Atrial fibrillation was present in 83 patients (19%), and 22% (n = 95) of the cohort had a pacemaker or automatic cardiac defibrillator implanted before the operation. Laparoscopic sleeve gastrectomy (72%, n = 318) and laparoscopic Roux-en-Y gastric bypass (25%, n = 110) were the most commonly performed bariatric procedures. Overall, patients stayed in the hospital for a median (interquartile range) of 2 (1 to 2) days. During the hospital stay, there were no deaths, myocardial infarctions, or documented episodes of thromboembolism. In conclusion, bariatric surgery in patients with HC is performed more frequently in recent years and is safe and associated with few perioperative complications. Because of the impact of obesity on long-term survival, clinicians should strongly consider bariatric surgery for obese HC patients who do not respond to conservative weight loss measures.
Presence of obstructive sleep apnea is associated with higher future readmissions and outpatient visits-a nationwide administrative dataset study
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Citation Excerpt :
With an estimated prevalence of about 15% in the United States, obstructive sleep apnea (OSA) is present in a significant proportion of hospitalized patients [2–5]. In patients undergoing elective surgery, several studies have linked OSA with an increased risk of pulmonary and cardiovascular complications, atrial fibrillation, desaturation, and difficult intubation in the perioperative period [6–8]. However, the currently available literature does not address the range of inpatient and outpatient clinical services potentially utilized by patients with OSA following an index hospitalization.
Hospital readmissions and outpatient visits contribute to the significant burden on healthcare systems. Obstructive sleep apnea (OSA) is a chronic medical condition that is associated with cardiovascular comorbidities and other chronic conditions. Inpatient and outpatient healthcare utilization rates in patients with OSA following hospitalization are unclear.
This. retrospective case–control cohort study utilized a nationwide database to assess if OSA is associated with higher healthcare utilization post-hospitalization. We compared healthcare utilization among patients with OSA versus without OSA between 2009 and 2014 after matching for demographic variables, geographic location, hospital environment, reason for admission, and severity of illness during hospitalization. We measured future healthcare utilization by the number of ICU admissions, hospital admissions, emergency room visits, and outpatient visits after being discharged from the index hospitalization.
Two equal-sized cohorts comprised of 85,912 matched pairs were obtained. The OSA cohort demonstrated significantly higher rates of future ICU admissions, hospital admissions, emergency room visits, and outpatient visits. Matching for comorbid cardiovascular conditions continued to demonstrate higher healthcare utilization in the OSA group. Short-term outcomes during the index hospitalization were relatively similar between groups.
This retrospective database study demonstrated that OSA may be an independent marker of higher future healthcare utilization. On the other hand, the length of stay during the index hospitalization was not elevated. Prospective studies are needed to confirm these findings and investigate the impact of directing additional resources to inpatients with OSA.
Comparison of eGFR formulas in determining chronic kidney disease stage in bariatric patients and the impact on perioperative outcomes
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Chronic kidney disease (CKD) independently increases the risk of 30-day adverse outcomes following metabolic and bariatric surgery (MBS). However, no studies have evaluated the stage of CKD at which increased perioperative risk is manifested. Here, we correlate 30-day major morbidities after MBS with extent of renal disease based on CKD Stage.
To determine the impact of CKD stage on perioperative outcomes after bariatric surgery.
Academic Hospital.
From the 2017 Metabolic and Bariatric Surgery Quality Improvement Program (MBSAQIP) database, we identified patients with CKD who underwent sleeve gastrectomy or laparoscopic gastric bypass surgery. Glomerular filtration rates (GFRs) were calculated and cohorts were generated based on CKD Stage. Complication rates and rates of morbidity and mortality were compared between stages, and strengths of correlation were calculated.
GFR and CKD Stage were calculated for 150,283 patients. There was a significant increase in the risk of major morbidity at each progressive stage of CKD (P < .001 for all compared stages). There was a strong positive linear correlation between increasing CKD Stage and total morbidity (r² = .983), including reoperation ( r² = .784), readmission (r² = .936), unplanned ICU transfer (r² = .853), and aggregate complications such as pulmonary (r² = .900), bleeding (r² = .878), or progressive worsening of renal function (r² = .845). In logistic regression, for every 10-point decrease in GFR, odds of total morbidity increased by 6%.
An increased risk of perioperative complications may be seen in early stages of CKD, and risk is compounded in more advanced stages. Bariatric surgical candidates should be counseled on their increased risk of surgical complications even with mild CKD, and the benefits of bariatric surgery should be carefully weighed against significantly increased risks of complications in severe CKD.
Healthcare utilization after elective surgery in patients with obstructive sleep apnea – analysis of a nationwide data set
2021, Sleep Medicine
Citation Excerpt :
We also found that the mortality during the index surgical admission was lower in the OSA group as compared to the matched cohorts. Although the results were counterintuitive, similar results of association in a negative direction have been reported in several prior studies [5–7]. It is worth noting that our study did not include patients who may have had readmission or death after the discharge from the index surgical admission.
Obstructive sleep apnea is prevalent among those undergoing elective surgery and likely introduces a risk of adverse outcomes. To understand its impact, we aimed to compare healthcare utilization in postsurgical patients with obstructive sleep apnea compared to controls matched on the surgical care environment.
This is a retrospective case–control cohort study using a nationwide database. Among patients undergoing elective surgical procedures during 2009–2014, we compared patients with obstructive sleep apnea with those without obstructive sleep apnea. The two cohorts were matched based on age, sex, type of surgery, performing surgeon, the hospital where the procedure was performed, and various All-Patient-Refined Diagnosis-Related-Groups severity indices. The primary effect of interest was short-term healthcare utilization. We also compared long-term hospital admissions, intensive care unit admissions, emergency room visits and outpatient visits.
47,719 subjects and controls were matched on a 1:1 basis. As the subjects were matched, the two groups did not differ on age, percent female, and various Diagnosis-Related-Groups severity indices. The obstructive sleep apnea group had more comorbid conditions and a higher Elixhauser index. Short-term healthcare utilization measured by the length of stay and mortality related to index procedure did not increase in the sleep apnea group. In hierarchical logistical regression analysis, the presence of sleep apnea predicted higher long-term health care utilization.
Our data suggests that the presence of sleep apnea was not associated with increased post elective surgical length of stay and mortality; however, the presence of obstructive sleep apnea was associated with long-term health care utilization.
Preoperative cardiac screening using NT-proBNP in obese patients 50 years and older undergoing bariatric surgery: a study of 310 consecutive patients
2021, Surgery for Obesity and Related Diseases
Obesity is associated with cardiovascular (CV) risk factors and diseases. Because bariatric surgery is increasingly performed in relatively elderly patients, a risk for pre- and postoperative CV complications exists.
We aimed to assess the value of plasma N-terminal-probrain natriuretic peptide (NT-proBNP) as a CV screening tool.
High-volume bariatric center.
Between June 2019 and January 2020, all consecutive bariatric patients 50 years and older underwent preoperative NT-proBNP assessment in this cohort study to screen for CV disease. Patients with elevated NT-proBNP (≥125 pg/mL) were referred for further cardiac evaluation, including electrocardiography and echocardiography.
We included 310 consecutive patients (median age, 56 years; 79% female; body mass index = 43±6.5 kg/m²). A history of CV disease was present in 21% of patients, mainly atrial fibrillation (7%) and coronary artery disease (10%). A total of 72 patients (23%) had elevated NT-proBNP levels, and 67 of them underwent further cardiac workup. Of these 67 patients, electrocardiography (ECG) showed atrial fibrillation in 7 patients (10%). On echocardiography, 3 patients had left ventricular ejection fraction (LVEF) <40%, 9 patients had LVEF 40%–49%, and 13 patients had LVEF ≥50% with structural and/or functional remodeling. In 2 patients, elevated NT-proBNP prompted workup leading to a diagnosis of coronary artery disease and consequent percutaneous coronary intervention in 1 patient.
Elevated NT-proBNP levels are present in 23% of patients 50 years and older undergoing bariatric surgery. In 37% of them, there was echocardiographic evidence for structural and/or functional remodeling. Further studies are needed to assess if these preliminary results warrant routine application of NT-proBNP to identify patients at risk for CV complications after bariatric surgery.
Clinical practice guidelines for the perioperative nutrition, metabolic, and nonsurgical support of patients undergoing bariatric procedures – 2019 update: cosponsored by American Association of Clinical Endocrinologists/American College of Endocrinology, The Obesity Society, American Society for Metabolic & Bariatric Surgery, Obesity Medicine Association, and American Society of Anesthesiologists
2020, Surgery for Obesity and Related Diseases
The development of these updated clinical practice guidelines (CPG) was commissioned by the American Association of Clinical Endocrinologists, The Obesity Society, the American Society of Metabolic and Bariatric Surgery, the Obesity Medicine Association, and the American Society of Anesthesiologists boards of directors in adherence to the American Association of Clinical Endocrinologists 2017 protocol for standardized production of CPG, algorithms, and checklists.
Each recommendation was evaluated and updated based on new evidence from 2013 to the present and subjective factors provided by experts.
New or updated topics in this CPG include contextualization in an adiposity-based, chronic disease complications–centric model, nuance-based, and algorithm/checklist-assisted clinical decision-making about procedure selection, novel bariatric procedures, enhanced recovery after bariatric surgery protocols, and logistical concerns (including cost factors) in the current healthcare arena. There are 85 numbered recommendations that have updated supporting evidence, of which 61 are revised and 12 are new. Noting that there can be multiple recommendation statements within a single numbered recommendation, there are 31 (13%) Grade A, 42 (17%) Grade B, 72 (29%) Grade C, and 101 (41%) Grade D recommendations. There are 858 citations, of which 81 (9.4%) are evidence level (EL) 1 (highest), 562 (65.5%) are EL 2, 72 (8.4%) are EL 3, and 143 (16.7%) are EL 4 (lowest).
Bariatric procedures remain a safe and effective intervention for higher-risk patients with obesity. Clinical decision–making should be evidence-based within the context of a chronic disease. A team approach to perioperative care is mandatory with special attention to nutritional and metabolic issues.

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Society of University SurgeonsPredictive factors of mortality in bariatric surgery: Data from the Nationwide Inpatient Sample

Background

Objectives

Methods

Results

Conclusion

Section snippets

Methods

Results

Discussion

J Am Coll Surg

SOARD

J Gastrointest Surg

Weight and type 2 diabetes after bariatric surgery: systematic review and meta-analysis

Am J Med

Long-term mortality after gastric bypass surgery

N Engl J Med

Surgery decreases long-term mortality, morbidity, and health care use in morbidly obese patients

Ann Surg

Accelerated Growth of Bariatric Surgery with the Introduction of Minimally Invasive Surgery

Arch Surg

Society of University Surgeons
Predictive factors of mortality in bariatric surgery: Data from the Nationwide Inpatient Sample