Patients with Obesity Have Better Long-Term Outcomes after Hospitalization for COPD Exacerbation

Potential confounders of the obesity paradox in older patients following transcatheter aortic valve replacement

PURPOSE

A higher body mass index (BMI) is associated with lower mortality in older patients following transcatheter aortic valve replacement (TAVR) for severe aortic valve stenosis. The current study aimed to investigate potential confounders of association between BMI and prognosis.

METHODS

The retrospective single-center study included consecutive patients following TAVR and excluded those in whom subcutaneous fat accumulation (SFA), visceral fat accumulation (VFA), and major psoas muscle (MPM) volume were not assessed by computed tomography. Cachexia was defined as a combination of BMI < 20 kg/m2 and any biochemical abnormalities.

RESULTS

After 2 patients were excluded, 234 (age, 86 ± 5 years; male, 77 [33%]; BMI, 22.4 ± 3.8 kg/m2; SFA, 109 (54-156) cm2; VFA, 71 (35-115) cm2; MPM, 202 (161-267) cm3; cachexia, 49 [21%]) were evaluated. SFA and VFA were strongly correlated with BMI (ρ = 0.734 and ρ = 0.712, respectively), whereas MPM was weakly correlated (ρ = 0.346). Two-year all-cause mortality was observed in 31 patients (13%). Higher BMI was associated with lower mortality (adjusted hazard ratio [aHR], 0.86; 95% confidence interval [CI], 0.77-0.95). A similar result was observed in the multivariate model including SFA (aHR in an increase of 20 cm2, 0.87; 95% CI, 0.77-0.98) instead of BMI, whereas VFA was not significant. Cachexia was a worse predictor (aHR, 2.51; 95% CI 1.11-5.65).

CONCLUSIONS

Association of higher BMI with lower mortality may be confounded by SFA in older patients following TAVR. Cachexia might reflect higher mortality in patients with lower BMI.

Co-existence of OSA and respiratory diseases and the influence of gender

INTRODUCTION

Sleep-disordered breathing (SDB), especially obstructive sleep apnea (OSA), is commonly associated with respiratory diseases, such as COPD, asthma and interstitial lung disease.

AREAS COVERED

This narrative review aims to comprehensively synthesize the existing information on SDB in respiratory diseases, investigate the role of gender in this association, and highlight the importance of OSA management in improving sleep, quality of life, and disease prognosis in these specific patient populations.

EXPERT OPINION

Research indicates a synergistic link between OSA and chronic respiratory diseases, which leads to greater morbidity and mortality compared to each disorder alone. Given the lack of an optimal OSA screening tool for these patients, a comprehensive patient approach and overnight diagnostic sleep study are imperative. Despite the limited evidence available, it seems that gender has an impact on the prevalence, severity, and susceptibility of this coexistence. Recognizing the role of gender in the coexistence of OSA and other respiratory diseases can enhance everyday medical practice and enable clinicians to adopt a more personalized approach toward optimal screening and diagnosis of these patients.

Influence of Diabetes Mellitus and Nutritional Parameters on Clinical and Functional Aspects and Quality of Life in Patients Hospitalized Due to Exacerbation of Chronic Obstructive Pulmonary Disease

Patients with chronic obstructive pulmonary disease (COPD) may experience exacerbations. During severe exacerbations, nutritional and endocrinological comorbidities can play an important role in the clinical and functional aspects of these patients. The aim of this study was to analyse the influence of the presence of diabetes mellitus (DM) and nutritional parameters on the deterioration of symptoms and quality of life during a severe exacerbation in patients with COPD. An observational study was conducted on COPD patients admitted due to an exacerbation. The COPD Assessment Test (CAT) questionnaire was administered, and clinical and functional parameters were compared based on the presence of nutritional and endocrinological alterations. A total of 50 patients were included, of whom 30 (60%) were male. The mean age was 70.5 years (standard deviation (SD) 9.6). The median CAT score during exacerbation was 25 (interquartile range (IQR) 17.5-30), and the baseline score was 13.5 (IQR 7-19), which represented a statistically significant difference (p < 0.001). Patients with iron deficiencies had a lower total CAT score (p = 0.041), specifically for items related to daily activity (p = 0.009) and energy (p = 0.007). Diabetic patients exhibited a greater decline in pulmonary function during exacerbation (p = 0.016), while patients with high thyroid-stimulating hormone (TSH) levels had a shorter hospital stay (p = 0.016). For COPD patients admitted due to an exacerbation, the metabolic assessment is useful and relevant in the clinical set-up, as endocrinological comorbidities negatively affect clinical and functional aspects of these patients.

Does the "Obesity Paradox" Have an Expiration Date? A Retrospective Cohort Study

(1) Background: The "obesity paradox" refers to a protective effect of higher body mass index (BMI) on mortality in acute infectious disease patients. However, the long-term impact of this paradox remains uncertain. (2) Methods: A retrospective study of patients diagnosed with community-acquired acute infectious diseases at Shamir Medical Center, Israel (2010-2020) was conducted. Patients were grouped by BMI: underweight, normal weight, overweight, and obesity classes I-III. Short- and long-term mortality rates were compared across these groups. (3) Results: Of the 25,226 patients, diverse demographics and comorbidities were observed across BMI categories. Short-term (90-day) and long-term (one-year) mortality rates were notably higher in underweight and normal-weight groups compared to others. Specifically, 90-day mortality was 22% and 13.2% for underweight and normal weight respectively, versus 7-9% for others (p < 0.001). Multivariate time series analysis revealed underweight individuals had a significantly higher 5-year mortality risk (HR 1.41 (95% CI 1.27-1.58, p < 0.001)), while overweight and obese categories had a reduced risk (overweight-HR 0.76 (95% CI 0.72-0.80, p < 0.001), obesity class I-HR 0.71 (95% CI 0.66-0.76, p < 0.001), obesity class II-HR 0.77 (95% CI 0.70-0.85, p < 0.001), and obesity class III-HR 0.79 (95% CI 0.67-0.92, p = 0.003)). (4) Conclusions: In this comprehensive study, obesity was independently associated with decreased short- and long-term mortality. These unexpected results prompt further exploration of this counterintuitive phenomenon.

Adipocyte dysfunction promotes lung inflammation and aberrant repair: a potential target of COPD

Background

Obesity and chronic obstructive pulmonary disease (COPD) are prevailing worldwide, bringing a heavy medical burden. Clinical and pathophysiological relationship between obesity and COPD is paradoxical and elusive. We aim to explore their inherent associations from clinical, genetic, and animal levels.

Methods

We performed literature review and cohort analysis of patients with COPD to compare lung function, symptom, and prognosis among different weight groups. After retrieving datasets of obesity and COPD in Gene Expression Omnibus (GEO) database, we carried out differentially expressed gene analysis, functional enrichment, protein-protein interactions network, and weighted gene co-expression network analysis. Then, we acquired paraffin-embedded lung tissues of fatty acid-binding protein 4-Cre-BMPR2fl/fl conditional knockout (CKO) mice that were characterized by adipocyte-specific knockout of bone morphogenetic protein receptor 2 (BMPR2) for staining and analysis.

Results

Our cohort study reports the effect of obesity on COPD is inconsistent with previous clinical studies. Lung function of overweight group was statistically superior to that of other groups. We also found that the inflammatory factors were significantly increased hub genes, and cytokine-associated pathways were enriched in white adipose tissue of patients with obesity. Similarly, injury repair-associated genes and pathways were further enhanced in the small airways of patients with COPD. CKO mice spontaneously developed lung injury, emphysema, and pulmonary vascular remodeling, along with increased infiltration of macrophages. BMPR2-defiecient adipocytes had dysregulated expression of adipocytokines.

Conclusion

Inflammation and abnormal repair might be potential mechanisms of the pathological association between obesity and COPD. BMPR2-associated adipocyte dysfunction promoted lung inflammation and aberrant repair, in which adipocytokines might play a role and thus could be a promising therapeutic target.

Obesity Paradox in Lung Diseases: What Explains It?

BACKGROUND

Obesity is a globally increasing health problem that impacts multiple organ systems and a potentially modifiable risk factor for many diseases. Obesity has a significant impact on lung function and is strongly linked to the pathophysiology that contributes to lung diseases. On the other hand, reports have emerged that obesity is associated with a better prognosis than for normal weight individuals in some lung diseases, including pneumonia, acute lung injury/acute respiratory distress syndrome, chronic obstructive pulmonary disease, and lung cancer. The lesser mortality and better prognosis in patients with obesity is known as obesity paradox. While obesity paradox is both recognized and disputed in epidemiological studies, recent research has suggested possible mechanisms.

SUMMARY

In this review, we attempted to explain and summarize these factors and mechanisms, including immune response, pulmonary fibrosis, lung function, microbiota, fat and muscle reserves, which are significantly altered by obesity and may contribute to the obesity paradox in lung diseases. We also discuss contrary literature that attributes the "obesity paradox" to confounding.

KEY MESSAGES

The review will illustrate the possible role of obesity in the prognosis or course of lung diseases, leading to a better understanding of the obesity paradox and provide hints for further basic and clinical research in lung diseases.

Sex-specific impact of anthropometric parameters on outcomes after transcatheter edge-to-edge repair for secondary mitral regurgitation

BACKGROUND

Body surface area (BSA) has been reported to be the stronger predictor for prognosis than body mass index in heart failure (HF) patients. The sex-specific association of BSA with mortality has been unclear.

METHODS

EuroSMR, a European multicenter registry, included patients who underwent edge-to-edge repair (TEER) for secondary mitral regurgitation (SMR). The outcome was two-year all-cause mortality.

RESULTS

The present cohort included 1594 HF patients (age, 74 ± 10 years; male, 66%). Association of calculated BSA with two-year all-cause mortality was evaluated. Patients were classified into three BSA groups: the lowest 10% (S), the highest 10% (L), and intermediate between S and L (M). Mean BSA was 1.87 ± 0.21 m² (male, 1.94 ± 0.18 m²; female, 1.73 ± 0.18 m²). The association of BSA with the endpoint in females showed a U-shaped curve, indicating worse prognosis for both S and L. The association in males followed a linear regression, demonstrating better prognosis for L. Hazard ratio (HR) of L to S in males was 0.43 (95% confidence interval [CI], 0.25-0.74; p = 0.002), whereas HR of L to M in females was 1.76 (95% CI, 1.11-2.78; p = 0.016) (p for interaction = 0.003).

CONCLUSIONS

Sex-specific association patterns demonstrate the complex influence of anthropomorphic factors in HF patients scheduled for TEER. Further investigation beyond simple evaluation of weight and height is needed for better comprehension of the obesity paradox and better prediction of the results of transcatheter therapy in HF patients.

BMI moderates the association between adverse childhood experiences and COPD

OBJECTIVES

Cigarette smoking and obesity are leading risk factors for chronic obstructive pulmonary disease (COPD). Although studies have established an association between adverse childhood experiences (ACEs) and COPD, few studies have examined whether this association is moderated by cigarette smoking or body mass index (BMI). This cross-sectional study examined the association between ACEs and COPD, and whether cigarette smoking or BMI moderates this association.

METHODS

Data for this study came from the 2019 Behavioral Risk Factor Surveillance System survey. An analytic sample of 75,700 adults aged 18-79 years (50.7% female) were analyzed using binary logistic regression. The outcome variable investigated was self-reported physician-diagnosed COPD, and the main explanatory variable was ACEs.

RESULTS

Of the 75,700 respondents examined, 8.1% had COPD. About one in three (33.6%) respondents had no ACEs, 23.1% had one ACE, and about one in five (20.2%) had four or more ACEs. In the multivariable binary logistic regression, we found that the association between ACEs and COPD differs by BMI status. Controlling for the effects of other factors, the association between ACEs and COPD is strongest for respondents who are obese (AOR = 1.41, 95% CI = 1.04-1.91).

CONCLUSIONS

The findings of this study demonstrate that ACEs are associated with COPD later in adulthood, and BMI moderated this association. The findings of this study add to the number of studies demonstrating the adverse impact of ACEs on chronic health outcomes among adults.

Mortality risk in patients with underweight or obesity with peripheral artery disease: a meta-analysis including 5,735,578 individuals

OBJECTIVES

The "obesity paradox" - in which patients with obesity exhibit superior survival than normal-weight counterparts - has been reported for several diseases. However, obesity is a well-known risk factor for cardiovascular disease, and whether the obesity paradox is present in peripheral artery disease (PAD) is unknown.

METHODS

A comprehensive search for studies that reported mortality in patients with PAD grouped by BMI identified 12 studies. We compared the survival of underweight patients with those who were not underweight, and patients with obesity against those without. Underweight was defined by a BMI value of <18.5 kg/m² in most studies and obesity by BMI ≥ 30 kg/m². Subgroup analyses were performed according to length of follow-up, presentation of PAD, and mode of revascularization. Meta-regression analyses were conducted, with covariates including age, sex, presence of coronary artery disease (CAD) and diabetes mellitus (DM).

RESULTS

The mortality risk of underweight patients with PAD was significantly higher compared to those who are not underweight (HR 1.72, 95% CI 1.38-2.14; I² = 84.2%). In contrast, the mortality risk of patients with obesity with PAD was significantly lower than those without (HR 0.78, 95% CI 0.62-0.97; I² = 89.8%). These findings remained consistent regardless of the presentation of PAD, revascularization, age, sex, or presence of CAD. The risk of death in the short-term of underweight patients (HR 1.50, 95% CI 0.47-4.72) and patients with obesity (HR 0.86, 95% CI 0.66-1.13) were not significantly different from their counterparts. The meta-regression showed that of the association between obesity and better survival was more pronounced in studies with a greater proportion of patients with concomitant CAD (regression coefficient -0.029, 95% CI -0.054 to -0.004).

CONCLUSIONS

In patients with PAD, mortality is higher among underweight patients and lower among patients with obesity. The mechanisms underlying the obesity paradox in patients with PAD remain to be elucidated, and further evidence is required to guide optimal weight control strategies in these patients.

Mortality Rate of Ischemic Stroke Patients Undergoing Decompressive Hemicraniectomy With Obesity

Background Obesity has been shown to have a positive mortality benefit in patients undergoing percutaneous coronary intervention and dialysis and those with rheumatoid arthritis, chronic obstructive pulmonary disease, and various wasting diseases. Studies for this mortality benefit in ischemic stroke patients are conflicting and have not been well studied in hemicraniectomy patients. We sought to determine the impact of obesity on outcomes of hemicraniectomy patients. Methods We performed a retrospective case-control database analysis using a multi-institutional database (TriNetX) looking at obese versus non-obese patients with ischemic stroke undergoing hemicraniectomy. Our primary endpoint was mortality. Secondary endpoints included seizure, pulmonary embolism, myocardial infarction (MI), cerebral infarction, deep vein thrombosis, tracheostomy, and percutaneous endoscopic gastrostomy. Cohorts were propensity-score matched for confounders. Results After propensity score matching for basic demographics and common comorbidities, as well as indicators of stroke severity, 646 patients were identified that were obese and had an ischemic stroke with subsequent hemicraniectomy (cohort 1), and 646 patients were identified who were non-obese with ischemic stroke and hemicraniectomy (cohort 2). Thirty-day survival rate was 98.142% in the obese vs. 87.771% in the non-obese cohorts, 90-day survival was 85.15% vs. 79.35%, 180-day survival was 96.44% vs. 84.52%, 365-day survival was 94.272% vs. 81.734%, and five-year survival was 81.889% vs. 75.077%, respectively. At five years, risk difference was -7.276% (95% CI: -11.757, -2.794) and odds ratio was 0.666 (95% CI: 0.510, 0.871) (p = 0.0029). Despite a higher mortality rate, obese patients had a statistically significant increase in pulmonary embolism (11.61% vs. 5.108, p < 0.0001), deep venous thrombosis (16.873% vs. 9.133%, p < 0.0001), and MI (8.824% vs. 5.882%, p = 0.0428). There was no significant difference in intensive care unit length of stay, ventilator dependence, tracheostomy placement, percutaneous endoscopic gastrostomy placement, or intracerebral hemorrhage. Conclusions Despite the increased risk of ischemic stroke, obese patients who undergo hemicraniectomy have decreased mortality rates compared to their non-obese counterparts.

Effects of Obstructive Sleep Apnea and Obesity on 30-Day Readmissions in Patients with Chronic Obstructive Pulmonary Disease: A Cross-Sectional Mediation Analysis

Rationale: Comorbidity is a significant driver of health status and healthcare utilization in chronic obstructive pulmonary disease (COPD). Obstructive sleep apnea (OSA) portends poorer outcomes, whereas obesity is protective. Objectives: We describe the prevalence and influence of these comorbidities on COPD readmissions. Methods: We collated discharge records for COPD exacerbations spanning 2010-2016 from the Nationwide Readmissions Database using Medicare's Hospital Readmissions Reduction Program criteria, with OSA-COPD overlap identified by concomitant diagnosis code for OSA. We used mixed-effects logistic regression to predict readmission odds. A cross-sectional mediation analysis was performed to evaluate the extent that OSA attenuated obesity's impact on readmission. Results: Of 1,662,983 qualifying COPD discharges, 19.1% carried a diagnosis of obesity and 12.9% had OSA, with both diagnoses present in 7.8%. In unadjusted analyses, obesity (odds ratio [OR], 1.04; 95% confidence interval [CI], 1.03-1.05; P < 0.001) and OSA (OR, 1.11; 95% CI, 1.10-1.13; P < 0.001) had increased readmission odds. In models adjusted for patient and hospital characteristics, 71% of readmission risk from obesity was attributable to OSA. When additionally adjusted for Charlson Comorbidity Index, we found that OSA remained a significant risk factor (OR, 1.05; 95% CI, 1.03-1.06; P < 0.001), whereas obesity remained protective (OR, 0.96; 95% CI, 0.94-0.97; P < 0.001) even after accounting for OSA. Conclusions: A significant proportion of patients with COPD suffer comorbid OSA and obesity with resultant readmission risk. Interestingly, obesity's protective effect attenuates readmission odds from OSA. Taken together, OSA and aggregate comorbidity influence readmissions in patients with COPD. Testing for and treating OSA-COPD overlap may provide a mechanism to reduce avoidable readmissions.

Statins Associated with Better Long-Term Outcomes in Aged Hospitalized Patients with COPD: A Real-World Experience from Pay-for-Performance Program

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death globally. Previous studies have addressed the impact of comorbidity on short-term mortality in patients with COPD. However, the prevalence of cardiovascular disease (CVD) and the association of statins prescription with mortality for aged COPD patients remains unclear. We enrolled 296 aged, hospitalized patients who were monitored in the pay-for-performance (P-4-P) program of COPD. Factors associated with long-term mortality were identified by Cox regression analysis. The median age of the study cohort was 80 years old, and the prevalence of coronary artery disease (CAD) and statins prescriptions were 16.6% and 31.4%, respectively. The mortality rate of the median 3-year follow-up was 51.4%. Through multivariate analysis, body mass index (BMI), statin prescription, and events of respiratory failure were associated with long-term mortality. A Cox analysis showed that statins prescription was associated with lower mortality (hazard ratio (HR): 0.5, 95% Confident interval, 95% CI: 0.34–0.73, p = 0.0004) and subgroup analysis showed that rosuvastatin prescription had protective effect on long-term mortality (HR: 0.44; 95% CI: 0.20–0.97; p < 0.05). Statin prescriptions might be associated with better long-term survival in aged COPD patients, especially those who experienced an acute exacerbation of COPD (AECOPD) who require hospitalization.

Mortality and Exacerbation Risk by Body Mass Index in Patients with COPD in TIOSPIR® and UPLIFT®

Rationale

There is an association between body mass index (BMI) and mortality in chronic obstructive pulmonary disease (COPD), with underweight individuals having higher mortality risk. Mortality and exacerbation risks among individuals with higher BMI are unclear.

Objectives

To examine the relationship between BMI and adverse outcomes in COPD.

Methods

This post hoc analysis included data from TIOSPIR (Tiotropium Safety and Performance in Respimat) (N = 17,116) and tiotropium-treated patients in UPLIFT (Understanding Potential Long-term Impacts on Function with Tiotropium) (N = 2,986). BMI classes (underweight [BMI < 20 kg/m²], normal weight [BMI 20 to <25 kg/m²], overweight [BMI 25 to <30 kg/m²], obesity class I [BMI 30 to <35 kg/m²], obesity class II [BMI 35 to <40 kg/m²], and obesity class III [BMI ⩾ 40 kg/m²]) were examined for adjusted associations with mortality, exacerbation, and nonfatal cardiovascular event risk using over 50,000 patient-years of cumulative follow-up data. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox regression models.

Results

In TIOSPIR, obesity prevalence was 22%, overweight 32%, and underweight 12%. The proportion of females was highest in obesity classes II and III. Overweight and obese participants had better baseline lung function versus other BMI classes; underweight participants were more likely to be current smokers. Underweight participants had a significantly higher risk of death (HR, 1.88; 95% CI, 1.62–2.20; P < 0.0001) and severe exacerbations (HR, 1.31; 95% CI, 1.16–1.47; P < 0.0001) versus normal-weight participants; however, overweight and obese participants were at lower to no additional risk. Results from UPLIFT were similar to TIOSPIR.

Conclusions

These results suggest that there is a strong association between body weight, COPD events, and risk of death. A holistic management approach taking into account respiratory and cardiovascular risk factors and nutritional status is needed to improve the general well-being of patients with COPD.