The Impact of Metabolic Syndrome and Obesity on Perioperative Total Joint Arthroplasty Outcomes: The Obesity Paradox and Risk Assessment in Total Joint Arthroplasty

The effect of Charlson Comorbidity Index, race, and surgical complications on postoperative knee outcomes after total knee arthroplasty

INTRODUCTION

Total Knee Arthroplasty (TKA) is the primary definitive treatment for knee osteoarthritis (OA) and has been essential in helping patients reduce knee pain and regain mobility. There is a need to assess whether various factors such as surgical complications from primary TKA, pre and postoperative range of motion (ROM), Charlson Comorbidity Index (CCI), comorbidities other than CCI, and demographics representative of an outpatient TKA population affect patient-reported outcome measures (PROMs).

MATERIALS AND METHODS

Retrospective chart review was performed on 444 patients who underwent TKA at an outpatient surgical facility. Demographics, qualitative, and quantitative measurements were collected at baseline, 4-6 months, and 1-year postoperatively. Patients were stratified by CCI into low (< 2), moderate (2-4), and high (> 4) risk categories. A generalized linear model was used to assess the relationship between time, complications, risk categories, and Knee injury and Osteoarthritis Outcome Score Joint Replacement (KOOS, JR).

RESULTS

Majority of patients were women (58.9%), non-Hispanic white (81.9%), categorized as moderate risk CCI (78.8%), with 22.5% experiencing complications post-TKA. KOOS, JR scores improved over time, with an increase of 18.1 points at 4-6 months and 26.1 points at 1-year post-TKA (p < 0.0001). Surgical complications were linked to a decrease of 3.5 points in KOOS, JR scores, whereas patients with high pre-TKA KOOS, JR scores had an increase of 6.4 points after surgery. Patients who identified as African American experienced an average of 4.7 points lower on KOOS, JR than non-Hispanic whites (p = 0.0211). High-risk patients (CCI > 4) on average, had higher KOOS, JR scores 12 months after TKA. African Americans and those with surgical complications reported Lower KOOS, JR scores.

CONCLUSIONS

TKA improved KOOS, JR scores through one year with the greatest improvement in PROM being in higher-risk patients, those without surgical complications. Patients with surgical complications and/or African American race had a lower average KOOS, JR score.

Increased Waist Circumference Is Associated With Severe Postoperative Medical Complications Following Total Knee Arthroplasty: Understanding Waist Circumference and Relation to Body Mass Index

BACKGROUND

Obesity is projected to affect nearly 42% of Americans nationwide by 2050. Waist circumference (WC), an estimate of central obesity or adiposity, has been shown to be a better predictor for cardiometabolic morbidity and mortality than body mass index (BMI), which does not consider body fat distribution. This study aimed to evaluate whether: 1) WC correlates with increasing BMI cohorts; and 2) WC is a predictor of severe Clavien-Dindo IV complications within 30 days following total knee arthroplasty (TKA).

METHODS

A national dataset was retrospectively queried to identify patients who received primary TKA for knee osteoarthritis between 2010 and 2020 (N = 385,996). A validated model converted each patient's BMI to WC. The BMI cohorts were grouped into underweight, healthy weight, overweight, and obesity classes 1 to 3. Primary outcomes included comparing WC among different BMI cohorts undergoing TKA. The secondary outcome was to evaluate if WC was associated with severe surgical complications within 30 days. Clavien-Dindo IV complications included cardiac arrests, myocardial infarctions, septic shock episodes, pulmonary emboli, acute renal failures, and cerebrovascular accidents. Multivariable logistic regressions were adjusted for age, functional status, frailty, various comorbidities, and obesity to evaluate the odds ratios (ORs) between WC and postoperative complications following TKA, with P-values less than 0.001 as significant.

RESULTS

The mean WC significantly correlated with increasing BMI cohorts (P < 0.001). The mean WC was significantly higher among patients who developed Clavien-Dindo IV complications (112.4 versus 110.5 centimeters, P < 0.001). For all TKA patients, each centimeter increase in WC was associated with developing a postoperative complication (OR: 1.11, P < 0.001). Subanalysis of only obese patients showed WC to be a better predictor than BMI class (OR: 1.35, P < 0.001).

CONCLUSIONS

Central adiposity, measured by WC, was associated with severe complications following TKA, even when controlling for obesity. Screening interventions using waist measurements may assist joint arthroplasty surgeons in risk-stratifying patients who have higher BMIs. Further study is warranted on how to integrate WC into TKA practice.

Effects of elevated body mass index on the success of total knee and total hip arthroplasty: a comprehensive overview

INTRODUCTION

The average body mass index (BMI) in the United States has tripled over the last five decades despite concerted population-based efforts for weight management. Elevated BMI and, in particular, obesity are risk factors for osteoarthritis. This trend has led to increased demands for total knee (TKA) and total hip arthroplasty (THA), necessitating an in-depth understanding of how elevated BMI impacts TKA and THA.

AREAS COVERED

This paper reviews the literature investigating the effects of elevated BMI, primarily obesity, on TKA and THA, focusing on preoperative, intraoperative, and postoperative considerations. It describes the associated risks, economic implications, and ethical considerations of patients with high BMIs undergoing TKA or THA. To ensure all relevant literature was included, Ovid Medline and Google Scholar databases were searched for the following terms, 'body mass index,' 'obesity,' 'knee,' 'hip,' and 'arthroplasty' for articles published from January 2019 through July 2024.

EXPERT OPINION

Despite the challenges of high BMI in TKA and THA, a deeper understanding of obesity as a chronic illness, coupled with advances in surgical techniques, can improve patient outcomes. A multidisciplinary approach and further research will optimize the care of patients with elevated BMIs undergoing total joint arthroplasty (TJA).

The impact of metabolic syndrome on short term radical cystectomy complications

PURPOSE

Radical cystectomy is a highly morbid procedure with short term perioperative complications rates cited to be as high as 60%. Short term perioperative complications have been demonstrated to be more frequent in underweight and overweight patients. We sought to evaluate the impact of metabolic syndrome on surgical outcomes.

MATERIALS AND METHODS

We identified 19,071 eligible patients who underwent radical cystectomy for nonmetastatic bladder cancer using the American College of Surgeons National Surgical Quality Improvement Program database between the years 2014 to 2021. The primary exposure was the presence of metabolic syndrome (body mass index >30, hypertension, diabetes) and included 1,566 patients. Our primary outcome was the development of a post operative surgical complication with secondary outcomes of the impact on length of stay, return to operating room, readmission, and 30 day mortality.

RESULTS

Metabolic syndrome was associated with an increased rate of complications following radical cystectomy (P < 0.001). Complications were demonstrated in 68% of patients with metabolic syndrome in comparison to 60% of those without. Following multivariable adjustment for relevant demographic, comorbidity, and treatment factors, compared to patients without metabolic syndrome, patients with metabolic syndrome were significantly more likely to experience a complication in the 30 days following cystectomy. Among the secondary outcomes, on multivariable analysis significant differences were found in the risk of readmission and extended length of stay. Critically, the risk of 30 day morbidity was associated with a 1.8 fold increase in those with metabolic syndrome.

CONCLUSIONS

Metabolic syndrome demonstrates significantly worse perioperative outcomes following radical cystectomy for bladder cancer.

Metabolic syndrome in the setting of obesity: impact on in-hospital complications and outcomes after total knee and hip arthroplasty

Aims

This study aims to evaluate the impact of metabolic syndrome in the setting of obesity on in-hospital outcomes and resource use after total joint replacement (TJR).

Methods

A retrospective analysis was conducted using the National Inpatient Sample from 2006 to the third quarter of 2015. Discharges representing patients aged 40 years and older with obesity (BMI > 30 kg/m2) who underwent primary TJR were included. Patients were stratified into two groups with and without metabolic syndrome. The inverse probability of treatment weighting (IPTW) method was used to balance covariates.

Results

The obese cohort with metabolic syndrome was significantly older, more likely to be female, had higher rates of Medicare insurance, and more likely to be non-Hispanic Black than the obese cohort without metabolic syndrome. In the unweighted analysis, patients with obesity and metabolic syndrome were more likely to experience cardiac, gastrointestinal, genitourinary, and postoperative anemia complications, had a longer length of stay, and were less likely to be discharged home compared to obese patients without metabolic syndrome. After adjusting for covariates using IPTW, patients with obesity and metabolic syndrome were more likely to experience postoperative anemia complications only and had lower rates of home discharge, but there were no significant differences in any other complication variables or length of stay.

Conclusion

Given the variability of metabolic health in obesity, the development of tailored perioperative protocols and recommendations acknowledging this variability in metabolic health in obese patients would ultimately potentially benefit patients and improve outcomes of TJR.

A component-based analysis of metabolic syndrome's impact on 30-day outcomes after hip fracture: reduced mortality in obese patients

Introduction

Hip fractures are a common injury associated with significant morbidity and mortality. In the United States, there has been a rapid increase in the prevalence of metabolic syndrome (MetS), a condition comprised several common comorbidities, including obesity, diabetes mellitus, and hypertension, that may worsen perioperative outcomes. This article assesses the impact of MetS and its components on outcomes after hip fracture surgery.

Methods

Patients who underwent nonelective operative treatment for traumatic hip fractures were identified in the 2015-2020 American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Baseline characteristics between groups were compared, and significant differences were included as covariates. Multivariate regression was performed to assess the impact of characteristics of interest on postoperative outcomes. Patients with MetS, or a single one of its constitutive components-hypertension, diabetes, and obesity-were compared with metabolically healthy cohorts.

Results

In total 95,338 patients were included. Patients with MetS had increased complications (OR 1.509; P < 0.001), but reduced mortality (OR 0.71; P < 0.001). Obesity alone was also associated with increased complications (OR 1.14; P < 0.001) and reduced mortality (OR 0.736; P < 0.001). Both hypertension and diabetes alone increased complications (P < 0.001) but had no impact on mortality. Patients with MetS did, however, have greater odds of adverse discharge (OR 1.516; P < 0.001), extended hospital stays (OR 1.18; P < 0.001), and reoperation (OR 1.297; P = 0.003), but no significant difference in readmission rate.

Conclusion

Patients with MetS had increased complications but decreased mortality. Our component-based analysis showed had obesity had a similar effect: increased complications but lower mortality. These results may help surgeons preoperatively counsel patients with hip fracture about their postoperative risks.

Components of metabolic syndrome as significant risk factors for postoperative complications following total shoulder arthroplasty: hypertension, diabetes, and obesity

Background

Metabolic syndrome (MetS) is a known risk factor for adverse postoperative outcomes. However, the literature surrounding the effects of MetS on orthopedic surgery outcomes following total shoulder arthroplasty (TSA) remains understudied. The purpose of this study is to investigate the effect of MetS on postoperative 30-day adverse outcomes following TSA.

Methods

The American College of Surgeons National Surgical Quality Improvement Program database was queried for all patients who underwent TSA between 2015 and 2020. After exclusion criteria, patients were divided into MetS and no MetS cohorts. MetS patients were defined as presence of hypertension, diabetes, and body mass index > 30 kg/m2. Bivariate logistic regression was used to compare patient demographics, comorbidities, and complications. Multivariate logistic regression, adjusted for all significant patient demographics and comorbidities, was used to identify the complications independently associated with MetS.

Results

A total of 26,613 patients remained after exclusion criteria, with 23,717 (89.1%) in the no MetS cohort and 2896 (10.9%) in the MetS cohort. On multivariate analysis, MetS was found to be an independent predictor of postoperative pneumonia (odds ratio [OR] 1.61, 95% confidence interval [CI] 1.02-2.55; P = .042), renal insufficiency (OR 4.09, 95% CI 1.67-10.00; P = .002), acute renal failure (OR 4.17, 95% CI 1.13-15.31; P = .032), myocardial infarction (OR 2.11, 95% CI 1.21-3.69; P = .009), nonhome discharge (OR 1.41, 95% CI 1.24-1.60; P < .001), and prolonged hospital stay > 3 days (OR 1.44, 95% CI 1.25-1.66; P < .001).

Conclusion

MetS was identified as an independent risk factor for postoperative pneumonia, renal insufficiency, acute renal failure, myocardial infarction, nonhome discharge, and prolonged hospital stay following TSA. These findings encourage physicians to medically optimize MetS patients prior to surgery to limit adverse outcomes.

Body Mass Index as a Predictor for Postoperative Complications Following Carpometacarpal Arthroplasty

Purpose

Carpometacarpal (CMC) arthroplasty is an effective surgical treatment to relieve pain and improve function for osteoarthritis of the CMC joint. The association between body mass index (BMI) and postoperative complications has been studied for other orthopedic procedures, including total knee arthroplasty, total hip arthroplasty, and total shoulder arthroplasty. However, BMI has not been studied as a risk factor for postoperative complications following CMC arthroplasty. The purpose of this study was to determine the postoperative complications associated with different categories of BMI following CMC arthroplasty. We hypothesized that increasing BMI is associated with more severe complications.

Methods

The American College of Surgeons National Surgical Quality Improvement Program database was queried for all patients who underwent CMC arthroplasty between 2015 and 2020. Patient demographics, comorbidities, surgical characteristics, and 30-day postoperative complication data were collected. Patients were stratified into cohorts based on BMI as follows: underweight (BMI < 18.5 kg/m2), normal/reference (18.5 kg/m2 ≤ BMI < 30.0 kg/m2), obese (30.0 kg/m2 ≤ BMI < 35.0 kg/m2), severely obese (35.0 kg/m2 ≤ BMI < 40.0 kg/m2), and morbidly obese (BMI ≥ 40.0 kg/m2). Multivariate logistic regression was used to identify postoperative complications associated with each cohort.

Results

In total, 6,432 patients were included in this study: 3,622 (56.3%) patients were included in the normal/reference cohort, 77 (1.2%) patients were included in the underweight cohort, 1,479 (23.0%) patients were included in the obese cohort, 718 (11.2%) patients were included in the severely obese cohort, and 536 (8.3%) patients were included in the morbidly obese cohort. The obese cohort was independently associated with a higher rate of superficial incisional surgical-site infection (odds ratio [OR], 2.11; 95% confidence interval [CI], 1.00-4.44; P = .050). The morbidly obese cohort was independently associated with readmission (OR, 3.35; 95% CI, 1.15-9.74; P = .026) and reoperation (OR, 3.40; 95% CI, 1.04-1.11; P = .043).

Conclusions

Morbid obesity is a clinically significant predictor for readmission and reoperation within 30 days following CMC arthroplasty. Obesity is a clinically significant predictor for superficial incisional surgical-site infection within 30 days following CMC arthroplasty.

Clinical relevance

A better understanding of BMI as a risk factor for postoperative complications may allow surgeons to improve preoperative risk stratification and patient counseling.

Type of study/level of evidence

Prognostic III.