Body weight and mortality in COPD: focus on the obesity paradox

Association of hepatic steatosis and liver fibrosis with chronic obstructive pulmonary disease among adults

With high prevalence and substantial mortality, metabolic dysfunction-associated steatotic liver disease and chronic obstructive pulmonary disease (COPD) are significant public health concerns. Utilizing a large, population-based dataset from the National Health and Nutrition Examination Survey, our study probes the relationship between COPD prevalence and hepatic steatosis and fibrosis, as measured by Vibration-Controlled Transient Elastography. We analyzed data from 693 individuals with COPD and 7229 without. Through weighted multivariate logistic regression analysis, a restricted cubic spline curve, and threshold effect analysis, we investigated the correlation between the severity of hepatic steatosis and fibrosis and the presence of COPD. Our findings revealed a positive correlation between the controlled attenuation parameter (CAP) and COPD prevalence [OR = 1.03 (95% CI 1.01, 1.05)], even after multivariate adjustment. Furthermore, we observed a U-shaped association between CAP and COPD, where the inflection point, CAP value of 264.85 dB/m, corresponded to the lowest COPD prevalence. Our study emphasizes a substantial and complex link between hepatic steatosis and COPD. These findings urge healthcare professionals to factor liver health into COPD management and prompt further exploration into the underlying mechanisms. This could pave the way for the development of improved prevention and treatment strategies.

Obesity and septic patient outcomes: Shaping the puzzle through age and sex perspectives

BACKGROUND & AIMS

While obesity has been reported as a protective factor in septic patients, little is known about the potential modifying effects of age and sex. The objective of this study is to investigate age and sex-specific associations between obesity and the prognosis of septic patients.

METHODS

A retrospective analysis was conducted on a cohort of 15,464 septic patients, categorized by body mass index (BMI) into four groups: underweight (<18.5 kg/m2, n = 483), normal (18.5-24.9 kg/m2, n = 4344), overweight (25-29.9 kg/m2, n = 4949) and obese (≥30 kg/m2, n = 5688). Multivariable logistic regression and inverse probability weighting were employed to robustly confirm the protective effect of a higher BMI on 28-day mortality, with normal weight serving as the reference category. Subgroup analyses based on age (young: 18-39, middle-aged: 40-64 and elderly: ≥65) and sex were performed.

RESULTS

The findings demonstrate that high BMI independently confers a protective effect against 28-day mortality in septic patients. However, the relationship between BMI and 28-day mortality exhibits a non-linear trend, with a BMI of 34.5 kg/m2 displaying the lowest odds ratio. Notably, the survival benefits associated with a high BMI were not observed in the young group. Moreover, being underweight emerges as an independent risk factor for middle-aged and elderly female patients, while in males it is only a risk factor in the elderly group. Interestingly, being overweight and obese were identified as independent protective factors in middle-aged and elderly male patients, but not in females.

CONCLUSIONS

The effect of BMI on mortality in septic patients varies according to age and sex. Elderly individuals with sepsis may derive more prognostic benefits from obesity.

Longitudinal BMI change and outcomes in Chronic Obstructive Pulmonary Disease: a nationwide population-based cohort study

BACKGROUND

The association between longitudinal body mass index (BMI) change and clinical outcomes in patients with chronic obstructive pulmonary disease (COPD) has not fully investigated.

METHODS

This retrospective cohort study included 116,463 COPD patients aged ≥ 40, with at least two health examinations, one within 2 years before and another within 3 years after COPD diagnosis (January 1, 2014, to December 31, 2019). Associations between BMI percentage change with all-cause mortality, primary endpoint, and initial severe exacerbation were assessed.

RESULTS

BMI decreased > 5% in 14,728 (12.6%), while maintained in 80,689 (69.2%), and increased > 5% in 21,046 (18.1%) after COPD diagnosis. Compared to maintenance group, adjusted hazard ratio (aHR) for all-cause mortality was 1.70 in BMI decrease group (95% CI:1.61, 1.79) and 1.13 in BMI increase group (95% CI:1.07, 1.20). In subgroup analysis, decrease in BMI showed a stronger effect on mortality as baseline BMI was lower, while an increase in BMI was related to an increase in mortality only in obese COPD patients with aHRs of 1.18 (95% CI: 1.03, 1.36). The aHRs for the risk of severe exacerbation (BMI decrease group and increase group vs. maintenance group) were 1.30 (95% CI:1.24, 1.35) and 1.12 (95% CI:1.07, 1.16), respectively.

CONCLUSIONS

A decrease in BMI was associated with an increased risk of all-cause mortality in a dose-dependent manner in patients with COPD. This was most significant in underweight patients. Regular monitoring for weight loss might be an important component for COPD management.

Body composition, pulmonary function tests, exercise capacity, and quality of life in chronic obstructive pulmonary disease patients with obesity

PURPOSE OF THE STUDY

Larger proportions of chronic obstructive pulmonary disease (COPD) patients are currently overweight or with obesity than underweight, and the combination of COPD and obesity is increasing. The purpose of this study was to investigate differences in the body composition, pulmonary function tests, exercise capacity, and health-related quality of life among normal weight, overweight, and obese patients with COPD.

STUDY DESIGN

A total of 514 patients with COPD were included in the study. According to the World Health Organization criteria for body mass index, the patients were classified as normal weight, overweight, and obese. Evaluations included fat-free mass, fat-free mass index, phase angle, pulmonary function tests, and 6-minute walk test. Dyspnea was assessed using the modified Medical Research Council dyspnea scale, and the health-related quality of life was evaluated using COPD Assessment Test and St. George's Respiratory Questionnaire. Values were compared among the three groups.

RESULTS

There were 315 male and 199 female patients, with a mean age of 66.7 ± 8.4 years. Fat-free mass, fat-free mass index, and phase angle values were significantly higher in COPD patients with obesity than in other patients (P < .001, P < .001, P < .001). Forced expiratory volume in 1 s, forced expiratory volume in 1 s/forced vital capacity, and diffusing capacity of lung for carbon monoxide value in pulmonary function tests were significantly higher in COPD patients with obesity than in other patients (P = .046, P < .001, P < .001), while the forced vital capacity values were similar in all groups. Exercise capacity (6-min walk test distance), dyspnea symptoms (modified Medical Research Council scale), and health-related quality of life (COPD Assessment Test and St. George's Respiratory Questionnaire) did not differ significantly between groups.

CONCLUSIONS

According to our study, obesity has no negative effect on pulmonary function tests, dyspnea perception, exercise capacity, and health-related quality of life.

Exacerbation rates in Japanese patients with obstructive lung disease: A subanalysis of the prospective, observational NOVELTY study

BACKGROUND

Although clinical trials including asthma and COPD patients have revealed much about exacerbation frequencies, most studies are limited in that they recruited patients only with a clear diagnosis of one disease or the other, based on conventional diagnostic criteria, which may exclude many real-world patients with mixed symptoms.

METHODS

NOVELTY is a global prospective observational study of patients with asthma and/or COPD from real-world practice. In this subanalysis, we compared patient characteristics of obstructive pulmonary diseases between the Japanese population (n = 820) and the overall population excluding Japanese patients (n = 10,406).

RESULTS

The Japanese population had fewer exacerbations than the overall population across most of the physician-assessed disease severities and all diagnoses. The difference in exacerbation frequencies was more prominent in patients with COPD and asthma + COPD. The Japanese population was older, had higher former smoking rates, lower BMI, fewer respiratory symptoms, and better health-related quality of life compared with the overall population across all diagnoses.

CONCLUSIONS

We clarified differences in patient characteristics among patients with asthma and/or COPD in Japan compared with non-Japanese patients. Importantly, we found that Japanese patients with asthma and/or COPD had significantly fewer exacerbations compared with patients overall. The results from our study may contribute to the development of precision medicine and guidelines specific to Japan.

Impact of the metabolic syndrome on cardiopulmonary morbidity and mortality in individuals with lung function impairment: a prospective cohort study of the Danish general population

Background

Whether the metabolic syndrome plays a role for the prognosis of individuals with lung function impairment (preserved ratio impaired spirometry (PRISm) or airflow limitation) is unclear. We hypothesised that the metabolic syndrome in individuals with lung function impairment is associated with increased cardiopulmonary morbidity and mortality.

Methods

The Copenhagen General Population Study was initiated in 2003 based on a random sample of white men and women aged 20-100 years drawn from the Danish general population. The risk of ischemic heart disease/heart failure, respiratory disease, and all-cause mortality was analysed with Cox models adjusted for age, sex, current smoking, and asthma during 15 years of follow-up.

Findings

Among 106,845 adults, 86,159 had normal lung function, 6126 had PRISm, and 14,560 had airflow limitation. We observed 10,448 hospital admissions for ischemic heart disease/heart failure, 21,140 for respiratory disease, and 11,125 deaths. Individuals with versus individuals without the metabolic syndrome generally had higher 5-year absolute risk of all outcomes, including within those with normal lung function, mild-moderate-severe PRISm, and very mild-mild-moderate-severe airflow limitation alike. Compared to individuals without the metabolic syndrome and with normal lung function, those with both the metabolic syndrome and severe PRISm had hazard ratios of 3.74 (95% CI: 2.53-5.55; p < 0.0001) for ischemic heart disease/heart failure, 5.02 (3.85-6.55; p < 0.0001) for respiratory disease, and 5.32 (3.76-7.54; p < 0.0001) for all-cause mortality. Corresponding hazard ratios in those with both the metabolic syndrome and severe airflow limitation were 2.89 (2.34-3.58; p < 0.0001) for ischemic heart disease/heart failure, 5.98 (5.28-6.78; p < 0.0001) for respiratory disease, and 4.16 (3.50-4.95; p < 0.0001) for all-cause mortality, respectively. The metabolic syndrome explained 13% and 27% of the influence of PRISm or airflow limitation on ischemic heart disease/heart failure and all-cause mortality.

Interpretation

The metabolic syndrome conferred increased risk of cardiopulmonary morbidity and mortality at all levels of lung function impairment.

Funding

Danish Lung Foundation, Danish Heart Foundation, Capital Region of Copenhagen, and Boehringer Ingelheim. JV is supported by the NIHR Manchester BRC.

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.

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.

Weight loss trend after bariatric surgery in a population of obese patients

BACKGROUND AND AIMS

Bariatric Surgery (BS) is a therapeutic option in patients with severe obesity whose non-surgical techniques have failed. No work has previously explored trajectories of weight loss and how long this was maintained. Aim of study is to describe effect of BS and nutritional intervention on body weight trend in patients with obesity.

METHODS

792 patients who underwent BS from 1996 to 2021 were included. The Protocol provides Laparoscopic Sleeve Gastrectomy (LSG), Vertical Gastroplasty (VBG) and Roux-en-Y Gastric Bypass (GB). %Total Weight Loss (%TWL) and %Excess Weight Loss (%EWL) were evaluated in three cohort of patients. Cumulative incidence of clinical goal after surgery was calculated at two and five years after BS.

RESULTS

At two years of follow-up, average %TWL and %EWL were 31.2% (95% CI = 29.0-33.4%) and 71% (95% CI = 65.4-76.5%) for VBG, 34.7% (95% CI = 33.8-35.6%) and 78.0% (95% CI = 75.9-89.1%) for GB and 33.8% (95% CI = 32.5-35.1%) and 68.8% (95% CI = 66.1-71.6%) for LSG. At two years from surgery the cumulative incidence of clinical goal was 70.7% (95% CI = 59.1-79.1%) for VBG, 86.4% (95% CI = 82.4-89.6%) for GB and 83.4% (95% CI = 76.0-87.1%) for LSG. At five years from surgery, average % TWL and % EWL were 22.5% (95% CI = 10.2-34.8%) and 58.2% (95% CI = 28.4-88.1%) for VBG, 31.8% (95% CI = 30.2-33.3%) and 70.8% (95% CI = 67.5-74.1%) for GB and 29.5% (95% CI = 26.2-32.8%) and 62.0% (95% CI = 53.4-70.6%) for LSG respectively. At five years after having reached clinical goal the share of people who were able to maintain their weight was 49.5% (95% CI = 30.8-79.6%) for VBG, 69.5% (95% CI = 58.3-82.8%) for GB and 55.9% (95% CI = 42.1-74.3%) for LSG. The median time of clinical goal maintaining was 4.8 years for VBG (95% CI lower limit = 4.1), 6.6 years for GB (95% CI lower limit = 6.2) and 5.3 years for LSG (95% CI lower limit = 4.8).

CONCLUSIONS

Our work confirm effectiveness of BS in patients with obesity and show that who do not reach clinical goal within 2 years, hardly will reach it later and suggest necessity for a medium and long-term follow-up to prevent weight regain.

Body mass index and risk of all-cause mortality among elderly Chinese: An empirical cohort study based on CLHLS data

The aim of our study was to evaluate the relationship between body mass index (BMI) and all-cause mortality among elderly Chinese. The subjects of our study were a cohort of 13 319 elderly Chinese enrolled between 2008 and 2018. Participants were classified in three groups: underweight (<18.5 kg/m²), normal weight (18.5-24.9 kg/m²), overweight and obese (≥25 kg/m²) according to different BMI levels. Cox proportional-hazards regression model was used to analyze the association between BMI grouping and the risk of mortality among the three groups and each corresponding subgroup. The restricted cubic spline regression was performed to investigate the variation tendency of BMI and mortality in different groups and subgroups. We found that the hazard ratios (HRs) of mortality in the underweight and the normal-weight groups were 1.213 and 1.104, respectively, compared with those in the overweight and obesity groups. HR for mortality decreased as BMI increased, although this phenomenon was not observed as not a linear relationship in all participants. Nonetheless, this nonlinear relationship was significant in type 2 diabetes patients. Among subjects with non-type 2 diabetes, the shape of the negative curve, reflecting the HR for BMI and mortality, decreased when BMI increased. Our findings suggest that an obesity paradox exists in non-type 2 diabetes patients, in which BMI has a nonlinear negative relationship with mortality. Conversely, in type 2 diabetes patients there is a U-shaped association. Obesity may thus be protective for all-cause mortality among non-diabetic older populations.

Obesity and the obesity paradox in patients with severe COVID-19

OBJECTIVE

To test the presence of the obesity paradox in two cohorts of patients hospitalized for COVID-19.

DESIGN

Two multicenter prospective cohorts.

SETTING

Three fourth level institutions.

PATIENTS

Adults hospitalized in the general ward for confirmed COVID-19 in the three institutions and those admitted to one of the 9 critical care units of one of the institutions.

INTERVENTIONS

None.

MAIN VARIABLES OF INTEREST

Categorized weight and its relationship with admission to the ICU in hospitalized patients and death in the ICU.

RESULT

Of 402 hospitalized patients, 30.1% were obese. Of these, 36.1% were admitted to the ICU vs. 27.1% of non-obese patients. Of the 302 ICU patients, 46.4% were obese. Of these, mortality was 45.0% vs. 52.5% for non-obese. The requirement to transfer hospitalized patients to the ICU admission get a HR of 1.47 (95%CI 0.87-2.51, p = 0.154) in the multivariate analysis. In intensive care patients, an HR of 0.99 (95%CI: 0.92-1.07, p = 0.806) was obtained to the association of obesity with mortality.

CONCLUSIONS

The present study does not demonstrate an association between obesity and risk of inpatient transfer to intensive care or death of intensive care patients due to COVID-19 therefore, the presence of an obesity paradox is not confirmed.

The Effect of Chronic Laxative Use on Lipid Profile and HbA1c: A Hospital-Based Retrospective Study

BACKGROUND

Laxatives are over-the-counter medications used as a treatment for constipation. The lipid-lowering effect of the long-term use of laxatives has been proposed.

AIM

To investigate the possible impact of the chronic use of laxatives on serum lipid profile, body mass index (BMI), and hemoglobin A1c (HbA1c).

METHODS

An observational retrospective cohort study was conducted to analyze data related to patients who received laxatives for six or 12 months or more in the KAUH database system. BMI, weight, cholesterol, triglycerides, low-density lipoprotein (LDL), high-density lipoprotein (HDL), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and HbA1c data were collected retrospectively from hospital records for three time points: baseline, six months, and 12 months of laxative treatment from the starting date for each patient.

RESULTS

A total of 106 patients' records fulfilled the inclusion criteria, 46 (43%) males with a mean age of 66 and 60 (57%) females with a mean age of 63. A significant decrease in plasma cholesterol and low-density lipoprotein-cholesterol (LDL-C) levels was observed in those who used laxatives for 12 months. Furthermore, an overall BMI and ALT reduction was seen in the combined. On the other hand, HbA1c levels appeared to improve in the combined group but not statistically significant. The change in the cholesterol level could be observed in patients receiving statin treatment and those without, with no statistical significance between the two groups.

CONCLUSION

Chronic laxative use for 12 months or more is associated with a decreased total and LDL-C level with no significant effect on high-density lipoprotein-cholesterol (HDL-C) levels. Additionally, there was a significant reduction in BMI and ALT. This effect is more prominent with combined therapy. Further multicentric studies on larger sample sizes are recommended to confirm our findings.

Interaction of BMI and respiratory status in obstructive sleep apnea, a cross-sectional COPD study

This cross-sectional study of 136 patients with chronic obstructive pulmonary disease (COPD) investigated the mechanism underlying overlap syndrome, defined as coexisting COPD and obstructive sleep apnea (OSA). OSA was defined as a respiratory event index (REI) ≥ 5 events/h, determined using type-3 portable monitors. The mean REI was 12.8 events/h. Most participants (60.1%) had mild OSA (REI: 5-15 events/h). The REI was positively correlated with forced expiratory volume in one second (%FEV1) (r = 0.33, p < 0.001), body mass index (BMI) (r = 0.24, p = 0.005), and fat-free mass index (r = 0.31, p = 0.005), and negatively correlated with residual volume divided by total lung capacity (r = -0.27, p = 0.003). Receiver-operating characteristic curve analysis revealed an optimal BMI cutoff of 21.96 kg/m2 for predicting moderate/severe OSA. A BMI ≥ 21.96 kg/m2 was associated with OSA among participants with %FEV1 ≥ 50%, but not those with %FEV1 < 50%. This study revealed an interaction between airflow limitation and hyperinflation, nutritional status, and OSA.

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.

Mucus Hypersecretion in Chronic Obstructive Pulmonary Disease and Its Treatment

Most patients diagnosed with chronic obstructive pulmonary disease (COPD) present with hallmark features of airway mucus hypersecretion, including cough and expectoration. Airway mucus function as a native immune system of the lung that severs to trap particulate matter and pathogens and allows them to clear from the lung via cough and ciliary transport. Chronic mucus hypersecretion (CMH) is the main factor contributing to the increased risk of morbidity and mortality in specific subsets of COPD patients. It is, therefore, primarily important to develop medications that suppress mucus hypersecretions in these patients. Although there have been some advances in COPD treatment, more work remains to be done to better understand the mechanism underlying airway mucus hypersecretion and seek more effective treatments. This review article discusses the structure and significance of mucus in the lungs focusing on gel-forming mucins and the impacts of CMH in the lungs. Furthermore, we summarize the article with pharmacological and nonpharmacological treatments as well as novel and interventional procedures to control CMH in COPD patients.

Factors Related to Fatigue and Physical Function in COPD: A Secondary Analysis Using National Survey Data

Fatigue in chronic obstructive pulmonary disease (COPD) is debilitating and associated with considerable morbidity. The aim of this study is to present a model based on the Theory of Unpleasant Symptoms of physiologic, psychologic, and situational factors with COPD-related fatigue and the relationship with physical functioning. This study used data collected from Wave 2 (2010-2011) of the National Social, Health, and Aging Project (NSHAP). A total of 518 adults with self-reported COPD were included in this study. Path analysis was used for hypothesis testing. Depression was the only psychologic factor found to have a direct relation to both fatigue (β = 0.158, p < .001) and physical function (β = -0.131, p = .001). Factors related to physical function included fatigue, depression, sleep, loneliness, and pain. Additionally, fatigue was indirectly associated with physical function via depression (β = -0.064, p = .012). These findings suggest avenues for future research on predictors of COPD-related fatigue in relation to physical functioning.

The Role of Smoking in the Mechanisms of Development of Chronic Obstructive Pulmonary Disease and Atherosclerosis

Tobacco smoking is a major cause of chronic obstructive pulmonary disease (COPD) and atherosclerotic cardiovascular disease (ASCVD). These diseases share common pathogenesis and significantly influence each other's clinical presentation and prognosis. There is increasing evidence that the mechanisms underlying the comorbidity of COPD and ASCVD are complex and multifactorial. Smoking-induced systemic inflammation, impaired endothelial function and oxidative stress may contribute to the development and progression of both diseases. The components present in tobacco smoke can have adverse effects on various cellular functions, including macrophages and endothelial cells. Smoking may also affect the innate immune system, impair apoptosis, and promote oxidative stress in the respiratory and vascular systems. The purpose of this review is to discuss the importance of smoking in the mechanisms underlying the comorbid course of COPD and ASCVD.

Analysis of the correlation between BMI and respiratory tract microbiota in acute exacerbation of COPD

Objective

To investigate the distribution differences in the respiratory tract microbiota of AECOPD patients in different BMI groups and explore its guiding value for treatment.

Methods

Sputum samples of thirty-eight AECOPD patients were collected. The patients were divided into low, normal and high BMI group. The sputum microbiota was sequenced by 16S rRNA detection technology, and the distribution of sputum microbiota was compared. Rarefaction curve, α-diversity, principal coordinate analysis (PCoA) and measurement of sputum microbiota abundance in each group were performed and analyzed by bioinformatics methods.

Results

1. The rarefaction curve in each BMI group reached a plateau. No significant differences were observed in the OTU total number or α-diversity index of microbiota in each group. PCoA showed significant differences in the distance matrix of sputum microbiota between the three groups, which was calculated by the Binary Jaccard and the Bray Curtis algorithm. 2. At the phylum level, most of the microbiota were Proteobacteria, Bacteroidetes Firmicutes, Actinobacteria, and Fusobacteria. At the genus level, most were Streptococcus, Prevotella, Haemophilus, Neisseria and Bacteroides. 3. At the phylum level, the abundance of Proteobacteria in the low group was significantly higher than that in normal and high BMI groups, the abundances of Firmicutes in the low and normal groups were significantly lower than that in high BMI groups. At the genus level, the abundance of Haemophilus in the low group was significantly higher than that in high BMI group, and the abundances of Streptococcus in the low and normal BMI groups were significantly lower than that in the high BMI group.

Conclusions

1. The sputum microbiota of AECOPD patients in different BMI groups covered almost all microbiota, and BMI had no significant association with total number of respiratory tract microbiota or α-diversity in AECOPD patients. However, there was a significant difference in the PCoA between different BMI groups. 2. The microbiota structure of AECOPD patients differed in different BMI groups. Gram-negative bacteria (G-) in the respiratory tract of patients predominated in the low BMI group, while gram-positive bacteria (G+) predominated in the high BMI group.

Clinical characteristics and predictors of pulmonary hypertension in chronic obstructive pulmonary disease at different altitudes

BACKGROUND

Pulmonary hypertension (PH) is a common complication in patients with chronic obstructive pulmonary disease (COPD) and is closely associated with poor prognosis. However, studies on the predictors of PH in COPD patients are limited, especially in populations living at high altitude (HA).

OBJECTIVES

To investigate the differences in the clinical characteristics and predictors of patients with COPD/COPD and PH (COPD-PH) from low altitude (LA, 600 m) and HA (2200 m).

METHODS

We performed a cross-sectional survey of 228 COPD patients of Han nationality admitted to the respiratory department of Qinghai People's Hospital (N = 113) and West China Hospital of Sichuan University (N = 115) between March 2019 and June 2021. PH was defined as a pulmonary arterial systolic pressure (PASP) > 36 mmHg measured using transthoracic echocardiography (TTE).

RESULTS

The proportion of PH in COPD patients living at HA was higher than that in patients living at LA (60.2% vs. 31.3%). COPD-PH patients from HA showed significantly different in baseline characteristics, laboratory tests and pulmonary function test. Multivariate logistic regression analysis indicated that the predictors of PH in COPD patients were different between the HA and LA groups.

CONCLUSIONS

The COPD patients living at HA had a higher proportion of PH than those living at LA. At LA, increased B-type natriuretic peptide (BNP) and direct bilirubin (DB) were predictors for PH in COPD patients. However, at HA, increased DB was a predictor of PH in COPD patients.

Association between abdominal and general obesity and respiratory symptoms, asthma and COPD. Results from the RHINE study

INTRODUCTION

Previous studies on the association between abdominal and general obesity and respiratory disease have provided conflicting results.

AIMS AND OBJECTIVES

We aimed to explore the associations of abdominal obesity with respiratory symptoms, asthma, and chronic obstructive pulmonary disease independently from general obesity in women and men.

METHODS

This cross-sectional study was based on the Respiratory Health in Northern Europe (RHINE) III questionnaire (n = 12 290) conducted in 2010-2012. Abdominal obesity was self-measured waist circumference using a sex-specific standard cut-off point: ≥102 cm in males and ≥88 cm in females. General obesity was defined as self-reported BMI ≥30.0 kg/m².

RESULTS

There were 4261 subjects (63% women) with abdominal obesity and 1837 subjects (50% women) with general obesity. Both abdominal and general obesity was independent of each other and associated with respiratory symptoms (odds ratio (OR) from 1.25 to 2.00)). Asthma was significantly associated with abdominal and general obesity in women, OR (95% CI) 1.56 (1.30-1.87) and 1.95 (1.56-2.43), respectively, but not in men, OR 1.22 (0.97-3.17) and 1.28 (0.97-1.68) respectively. A similar sex difference was found for self-reported chronic obstructive pulmonary disease.

CONCLUSIONS

General and abdominal obesity were independent factors associated with respiratory symptoms in adults. Asthma and chronic obstructive pulmonary disease were independently linked to abdominal and general obesity in women but not men.

Body composition and mortality in a cohort study of Chinese patients with hypertrophic cardiomyopathy

Objective

To analyse the characteristics and mortality of hypertrophic cardiomyopathy (HCM) patients with different body compositions.

Methods

In this study, 530 consecutive patients with HCM at West China Hospital were studied from November 2008 to May 2016. An equation based on body mass index (BMI) was used to obtain the Percent body fat (BF) and lean mass index (LMI). Patients were divided into five sex-specific BMI, BF and LMI quintiles.

Results

The average BMI, BF and LMI were 23.1 ± 3.2 kg/m2, 28.1 ± 7.3% and 16.5 ± 2.2 kg/m2, respectively. Patients with higher BMI or BF were older and had more symptoms and adverse cardiovascular conditions; those with higher LMI were younger and had less coronary artery disease and lower serum NT-proBNP and creatine. BF correlated positively with resting left ventricular (LV) outflow tract gradient, mitral regurgitation (MR) degree and left atrial diameter but was inversely associated with septal wall thickness (SWT), posterior wall thickness (PWT), LV mass, and E/A ratio; LMI was positively correlated with SWT, LV end diastolic volume and LV mass but was negatively associated with MR degree.48 all-cause deaths occurred during a median follow-up of 33.8 months. Reversed J-shape associations of BMI and LMI with mortality were observed. A lower BMI or LMI was significantly associated with high mortality, especially for low-moderate BMI and LMI. No significant difference in mortality was found across BF quintiles.

Conclusions

The associations of BMI, BF and LMI with baseline characteristics and cardiac remodelling are different in HCM patients. In Chinese HCM patients, low BMI and LMI predicted mortality but not BF.

Interrelationships between tuberculosis and chronic obstructive pulmonary disease

PURPOSE OF REVIEW

Our objective was to review the current literature regarding socioeconomic, environmental, clinical, and immunologic factors common to chronic obstructive pulmonary disease (COPD) and tuberculosis (TB).

RECENT FINDINGS

Recent studies suggest that TB patients might be at increased risk for developing COPD. Conversely, additional prospective cohort studies have determined that COPD patients are at increased risk for active TB: a risk that appears to be partially mediated through inhaled corticosteroid use. Tobacco smoking, poverty, air pollution, and malnutrition are associated with COPD and TB. Vitamin D has been shown to prevent COPD exacerbations, but its use for preventing TB infection remains unclear. Surfactant deficiency, elevated matrix metalloproteinases, and toll-like receptor 4 polymorphisms play key roles in the pathogenesis of both diseases.

SUMMARY

Recent studies have elucidated interrelationships between COPD and TB. Future research is needed to optimize clinical and public health approaches that could mitigate risk factors contributing to both diseases.

Higher Muscle Mass and Higher Serum Prealbumin Levels Are Associated with Better Survival in Hemodialysis Patients during a Five-Year Observation Period

BACKGROUND

Dialysis is the most commonly used renal replacement therapy in patients with end-stage renal disease. The mortality rate of hemodialysis patients is 15-20%, with cardiovascular complications being the most common. There is an association between the severity of atherosclerosis and both the development of protein-calorie malnutrition and inflammatory mediators. The aim of this study was to assess the relationship between biochemical markers of nutritional status, body composition and survival in hemodialysis patients.

METHODS

Fifty-three hemodialysis patients were included in the study. Serum albumin, prealbumin, and IL-6 levels were measured, as well as body weight, body mass index, fat content and muscle mass. The five-year survival of patients was calculated using Kaplan-Meier estimators. The long-rank test was used for univariate comparison of survival curves, and the Cox proportional hazards model was used for multivariate analysis of survival predictors.

RESULTS

There were 47 deaths, 34 of which were due to cardiovascular disease. The hazard ratio (HR) for age in the middle-aged group (55-65 years) was 1.28 (confidence interval [CI] 0.58, 2.79) and 5.43 (CI 2.1, 14.07; statistically significant) for the oldest age group (over 65 years). A prealbumin level above 30 mg/dl was associated with an HR of 0.45 (CI 0.24, 0.84). Serum prealbumin (odds ratio [OR] = 5.23; CI 1.41, 19.43; p = 0.013) and muscle mass (OR = 7.5; CI 1.31, 43.03; p = 0.024) were significant predictors of all-cause mortality.

CONCLUSIONS

Prealbumin level and muscle mass were associated with increased mortality risk. Identification of these factors may improve the survival of hemodialysis patients.

Obesity Paradox: Fact or Fiction?

PURPOSE OF REVIEW

Obesity is related to several comorbidities such as type 2 diabetes mellitus, cardiovascular disease, heart failure, and various types of cancers. While the detrimental effect of obesity in both mortality and morbidity has been well established, the concept of the obesity paradox in specific chronic diseases remains a topic of continuous interest. In the present review, we examine the controversial issues around the obesity paradox in certain conditions such as cardiovascular disease, several types of cancer and chronic obstructive pulmonary disease, and the factors that may confound the relation between obesity and mortality.

RECENT FINDINGS

We refer to the obesity paradox when particular chronic diseases exhibit an interesting "paradoxical" protective association between the body mass index (BMI) and clinical outcomes. This association, however, may be driven by multiple factors among which the limitations of the BMI itself; the unintended weight loss precipitated by chronic illness; the various phenotypes of obesity, i.e., sarcopenic obesity or the athlete's obesity phenotype; and the cardiorespiratory fitness levels of the included patients. Recent evidence highlighted that previous cardioprotective medications, obesity duration, and smoking status seem to play a role in the obesity paradox. The obesity paradox has been described in a plethora of chronic diseases. It cannot be emphasized enough that the incomplete information received from a single BMI measurement may interfere with outcomes of studies arguing in favor of the obesity paradox. Thus, the development of carefully designed studies, unhampered by confounding factors, is of great importance.

Impact of Obesity on In-Hospital Morbidity and Mortality Among Patients Admitted for Acute Exacerbations of Chronic Obstructive Pulmonary Disease (COPD)

Background Obesity has been considered to be a risk factor for increased morbidity and mortality among patients with cardiopulmonary diseases. The burden of chronic obstructive pulmonary disease (COPD) and obesity is very high in the United States. We aimed to use the National Inpatient Sample (NIS) to evaluate the impact of obesity on the outcomes of patients hospitalized with COPD exacerbation. Materials & Methods This is a retrospective cohort study from the NIS database involving adult patients hospitalized for COPD exacerbation in the year 2019 obtained using the international classification of diseases, 10^th revision coding system (ICD-10). Obese and morbidly obese subgroups were identified. Statistical analyses were done using the Stata software, and regression analysis was performed to calculate odds ratios. Adjusted odds ratios (aOR) were calculated after adjusting for potential confounders. Results Among patients hospitalized for COPD exacerbations, mortality rates were lower among obese and morbidly obese patients; aOR 0.72 [0.65, 0.80] and aOR 0.88 [0.77-0.99], respectively. Obese and morbidly obese were more likely to require non-invasive ventilation aOR 1.63 [1.55, 1.7] and aOR 1.93 [1.85-2.05], respectively, and were more likely to require mechanical ventilation aOR 1.25 [1.19, 1.31], and aOR 1.53 [1.44-1.62], respectively. The tracheostomy rate was 1.17%, 0.83%, and 0.38% among patients with morbid obesity, obesity, and nonobese patients, respectively. Obese (aOR 1.11 [1.07-1.14]) and morbidly obese patients (aOR 1.21 [1.16-1.26]) had higher odds of being discharged on home oxygen and to a skilled nursing facility (SNF), aOR 1.32[1.27-1.38] and aOR 1.37 [1.3-1.43], respectively. Average hospital charges and length of hospitalization were significantly higher for morbidly obese and obese patients as compared to non-obese patients (p < 0.01). Conclusions Among admissions for COPD exacerbation, the rates of non-invasive ventilation, mechanical ventilation, tracheostomy, discharge with supplemental oxygen, length of hospitalization, hospitalization charges, and discharge to an SNF were higher among obese patients representing a higher morbidity and healthcare utilization in this group. This, however, did not translate into increased mortality among obese patients admitted with COPD exacerbations, and further randomized controlled trials are required to confirm our findings.

Predictive value of the hemoglobin-albumin-lymphocyte-platelet (HALP) index for ICU mortality in patients with acute exacerbations of chronic obstructive pulmonary disease (AECOPD)

The combined index of hemoglobin, albumin, lymphocyte, and platelet (HALP) is a novel indicator reflecting systemic inflammation and nutritional status. To explore the relationship between HALP score and ICU mortality risk in patients with acute exacerbations of chronic obstructive pulmonary disease (AECOPD). A total of 1533 AECOPD patients from the eICU Collaborative Research Database (eICU-CRD) between 2014 and 2015 were included in this retrospective cohort study. Univariate and multivariate Cox proportional hazards models were utilized to investigate the association of HALP score, platelet-to-lymphocyte ratio (PLR) score, and lymphocyte-to-monocyte ratio (LMR) score with the ICU mortality risk in patients with AECOPD. Stratified analyses were performed based on patients' ICU admission type, body mass index (BMI), and Acute Physiology, Age and Chronic Health Evaluation IV (APACHE IV) score. Of these 1533 AECOPD patients, 123 (8.00%) patients died in the ICU. Low HALP score [hazard ratio (HR) = 1.69; 95% confidence interval (CI) 1.14-2.53] and low LMR score (HR = 1.60; 95% CI 1.07-2.39) were associated with an increased ICU mortality risk in patients with AECOPD after adjusting for all confounders. Stratified analyses indicated that low HALP score were still associated with a higher ICU mortality risk in patients admitted to ICU by emergency (HR = 1.81; 95% CI 1.11-2.96), obese patients (HR = 2.81; 95% CI 1.29-6.10), and patients with low APACHE scores (HR = 2.87; 95% CI 1.75-4.69). Low HALP score was associated with an increased risk of ICU mortality in patients with AECOPD, suggesting that the HALP score may be a novel prognostic predictor in patients with AECOPD.

The Overlap Syndrome of Obstructive Sleep Apnea and Chronic Obstructive Pulmonary Disease: A Systematic Review

Chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) are common diseases that strongly impact the quality and length of life. Their coexistence is determined by overlap syndrome (OS). This systematic review aims to define the significance of these comorbidities according to the current state of knowledge. For this systematic review, we searched PubMed, Scopus, and Cochrane for studies published between 2018 and 26 October 2022, to find original, observational, human studies published in English, where the diagnosis of COPD was according to the Global Initiative for Obstructive Lung Disease guidelines and the diagnosis of OSA was based on polysomnography. The quality of studies was assessed using the Newcastle-Ottawa quality assessment tool for cohort and case-control studies, as well as its modification for cross-sectional studies. Of the 1548 records identified, 38 were eligible and included in this systematic review. The included studies covered a total population of 27,064 participants. This paper summarizes the most important, up-to-date information regarding OS, including the prevalence, meaning of age/gender/body mass index, polysomnography findings, pulmonary function, comorbidities, predicting OSA among COPD patients, and treatment of this syndrome.

Associations between body mass index, weight loss and overall survival in patients with advanced lung cancer

BACKGROUND

Weight loss (WL) has been associated with shorter survival in patients with advanced cancer, while obesity has been associated with longer survival. Integrating body mass index (BMI) and WL provides a powerful prognostic tool but has not been well-studied in lung cancer patients, particularly in the setting of clinical trials.

METHODS

We analysed patient data (n = 10 128) from 63 National Cancer Institute sponsored advanced non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) trials. Risk matrices were created using BMI and WL percentage, which were divided into 'grades' based on median survival. Relationships between survival, BMI and WL percentage were examined using Kaplan-Meier estimators and Cox proportional hazards (PH) models with restricted cubic splines.

RESULTS

For NSCLC, a twofold difference was noted in median survival between the BMI > 28 and WL ≤ 5% group (13.5 months) compared with the BMI < 20 and WL > 5% group (6.6 months). These associations were less pronounced in SCLC. Kaplan-Meier curves showed significant survival differences between grades for both NSCLC and SCLC (log-rank, P < 0.0001). In Stage IV NSCLC, Cox PH analyses with restricted cubic splines demonstrated significant associations between BMI and survival in both WL ≤ 5% (P = 0.0004) and >5% (P = 0.0129) groups, as well as in WL > 5% in Stage III (P = 0.0306). In SCLC, these relationships were more complex.

CONCLUSIONS

BMI and WL have strong associations with overall survival in patients with advanced lung cancer, with a greater impact seen in NSCLC compared with SCLC. The integration of a BMI/WL grading scale may provide additional prognostic information and should be included in the evaluation of therapeutic interventions in future clinical trials in advanced lung cancer.

A Longitudinal Study of Trajectories and Factors Influencing Patient-Reported Outcomes in Chronic Obstructive Pulmonary Disease

PURPOSE

To explore the trajectory of patient-reported outcomes and the factors influencing them in patients with COPD.

PATIENTS AND METHODS

The study population, 236 patients with stable COPD who attended the outpatient clinic of the Department of Respiratory and Critical Care Medicine in a tertiary care hospital in Nanning City between October 2020 and November 2021, answered the modified patient-reported outcome scale for COPD (mCOPD-PRO). Patient-reported outcomes were investigated at the time of the patient's outpatient visit (T1), 1 month after the visit (T2), 3 months after the visit (T3), and 6 months after the visit (T4). Latent class growth modeling was used to determine the number and shape of trajectories, and multinomial logistic regression analysis were used to explore influence factors of each class.

RESULTS

COPD patients' reported outcome trajectories were classified into 3 categories: health low-level group (14.80%), health risk group (54.70%), and good health group (30.50%). Logistic regression analysis showed that gender, BMI, smoking history, number of comorbidities, whether it was their first visit, and lung function classification were influential factors in patients' reported outcome trajectories (P<0.05). Female, obese, had a history of smoking, number of comorbid diseases >3, first diagnosis, and lung function class IV had a higher probability of entering the healthy low-level group.

CONCLUSION

COPD patients have poor self-reported health levels during the first 6 months after the outpatient visit, and there is group heterogeneity in patient-reported outcome trajectories; medical staff should give patients specific nursing interventions based on their current development of COPD, self-reported changes, and other relevant influencing factors.

National Trends in Prevalence of Depression in Men and Women with Chronic Obstructive Pulmonary Disease Hospitalized in Spain, 2016–2020

(1) Background: To describe trends in the prevalence of depression in men and women with COPD hospitalized in Spain (2016–2020). (2) Methods: We used a nationwide discharge database to select all patients ≥35 years with COPD. (3) Results: The prevalence of depression was 3.54-times higher in women with COPD than in men (OR 3.54; 95%CI 3.48–3.6). It decreased significantly between 2016 and 2020, although the reduction was only significant in women (12.27% in 2016 vs. 10.56% in 2020). Older age, comorbidity and the most recent years of hospital admission were associated with lower prevalence of depression in both men and women, while obesity, obstructive sleep apnea (OSA) and use of oxygen prior to admission were risk factors. In-hospital mortality (IHM) increased significantly over time. Older age, comorbidity, the use of oxygen prior to admission and having been hospitalized in 2020 increased the risk of IHM. Female sex was associated with a lower IHM in patients with depression and COPD. (4) Conclusions: The prevalence of depression has decreased over time in women with COPD while it has not changed significantly in men with this disease. IHM increased over time both in men and women with COPD and depression, with higher prevalence in the former.

The Relationship Between BMI and Lung Function in Populations with Different Characteristics: A Cross-Sectional Study Based on the Enjoying Breathing Program in China

Purpose

To analyze the relationship between body mass index (BMI) and lung function, which may help optimize the screening and management process for chronic obstructive pulmonary disease (COPD) in the early stages.

Patients and Methods

In this cross-sectional study using data from the Enjoying Breathing Program in China, participants were divided into two groups according to COPD Screening Questionnaire (COPD-SQ) scores (at risk and not at risk of COPD) and three groups based on lung function (normal lung function, preserved ratio impaired spirometry [PRISm], and obstructive lung function).

Results

A total of 32,033 subjects were enrolled in the current analysis. First, in people at risk of COPD, overweight and obese participants had better forced expiratory volume in one second (FEV1; overweight: 0.33 liters (l), 95% confidence interval [CI]: 0.27 to 0.38; obesity: 0.31 L, 95% CI: 0.22 to 0.39) values than the normal BMI group. Second, among people with PRISm, underweight participants had a lower FEV1 (−0.56 L, 95% CI: −0.86 to −0.26) and forced vital capacity (FVC; −0.33 L, 95% CI: −0.55 to −0.11) than participants with a normal weight, and obese participants had a higher FEV1 (0.22 L, 95% CI: 0.02 to 0.42) and FVC (0.16 L, 95% CI: 0.02 to 0.30) than participants with a normal weight. Taking normal BMI as the reference group, lower FEV1 (−0.80 L, 95% CI: −0.97 to −0.63) and FVC (−0.53 L, 95% CI: −0.64 to −0.42) were found in underweight participants with obstructive spirometry, and better FEV1 (obesity: 0.26 L, 95% CI: 0.12 to 0.40) was found in obese participants with obstructive spirometry.

Conclusion

Being underweight and severely obese are associated with reduced lung function. Slight obesity was shown to be a protective factor for lung function in people at risk of COPD and those with PRISm.

The associations between body composition and vital capacity index of medical students in Shenyang of China: a cross-sectional survey

Objectives

This study aimed to examine the associations between body composition and vital capacity index (VCI) among medical students of Shenyang, China.

Study design

The design of this study is a cross-sectional study.

Methods

Participants were 2063 individuals (17–25 years) from a medical college in Shenyang, who participated in this survey from April to May 2017. Height, weight, fat mass (FM), fat free mass (FFM), protein mass (PM), total body water (TBW), mineral mass (MM), vital capacity were measured, then BMI and VCI were calculated. Stepwise multiple linear regression analysis was used to evaluate the effect of body composition on VCI of participants in different genders. In addition, subgroup analysis was carried out according to BMI levels.

Results

Male students showed significantly higher height, weight, BMI, FFM, PM, TBW, MM, VC, and VCI, but lower FM in comparison with female students. Stepwise multiple linear regression analysis showed that in both sexes FM was negatively correlated with VCI which represents pulmonary function (r < 0; P < 0.001). After dividing the whole participants by BMI, further correlation analysis showed FM was positively correlated with VCI only for male subgroups with BMI < 18.5 (r > 0; P = 0.050).

Conclusion

Overall, FM is highly negatively correlated with the VCI of Chinese medical students of both genders. However, there was a positive correlation between FM and VCI among low-weight male students.

Airway immune response in the mouse models of obesity-related asthma

The prevalence rates of obesity and its complications have increased dramatically worldwide. Obesity can lead to low-grade chronic systemic inflammation, which predisposes individuals to an increased risk of morbidity and mortality. Although obesity has received considerable interest in recent years, the essential role of obesity in asthma development has not been explored. Asthma is a common chronic inflammatory airway disease caused by various environmental allergens. Obesity is a critical risk factor for asthma exacerbation due to systemic inflammation, and obesity-related asthma is listed as an asthma phenotype. A suitable model can contribute to the understanding of the in-depth mechanisms of obese asthma. However, stable models for simulating clinical phenotypes and the impact of modeling on immune response vary across studies. Given that inflammation is one of the central mechanisms in asthma pathogenesis, this review will discuss immune responses in the airways of obese asthmatic mice on the basis of diverse modeling protocols.

Stability of distinct symptom experiences in patients with chronic obstructive pulmonary disease (COPD)

PURPOSE

This study aimed to examine reclassification rates among classes of chronic obstructive pulmonary disease (COPD) patients based on their distinct symptom experiences and to assess how these subgroups differed in symptom scores and health-related quality of life (HRQoL) outcomes over one year. Moreover, we wished to assess how these subgroups differed in demographic and clinical characteristics at 12 months.

PATIENTS AND METHODS

This is a follow-up study of 267 patients with moderate, severe, and very severe COPD. Based on their distinct symptom experiences using the Memorial Symptom Assessment Scale (MSAS), three subgroups (i.e., "high", "intermediate", and "low") were identified at baseline. In the present study, transitions between the subgroups at three, six, nine, and 12 months were investigated and calculated as reclassification rates. Differences among the subgroups in symptom scores and HRQoL at each time point and demographic and clinical characteristics at 12 months were evaluated using analysis of variance with post hoc comparisons.

RESULTS

Almost 65% were still in the "high" class after 12 months. At 12 months, pairwise comparisons for respiratory function measurements were not significantly different. Compared to the "intermediate" and "low" class, patients in the "high" class were more likely to be women and had significantly more comorbidities, reported a significantly higher number of symptoms at all time points, and worse HRQoL scores.

CONCLUSION

Our findings suggest that the pattern of a high symptom burden in COPD is consistent over time. The patients' individual symptom experiences should be the primary focus of treatment.

Association of fatty liver index with all-cause and disease-specific mortality: A nationwide cohort study

BACKGROUND

Population-based data regarding the prognostic implications of hepatic steatosis have been inconsistent. We examined the association between the fatty liver index (FLI) with all-cause and disease-specific mortality in the general population.

METHODS

We included subjects who underwent a health examination in 2009 using the Korean nationwide health screening database. Death and cause of death data were provided by Statistics Korea. The causes of death were classified using 10th Revision of the International Classification of Diseases codes.

RESULTS

Among the included 10,585,844 participants, there were 418,296 deaths during a median follow-up period of 8.3 years. When adjusting for possible confounding factors, the risk of all-cause mortality linearly increased with a higher FLI score (hazard ratio [HR], 95% confidence interval [CI]: FLI 30-59, 1.19, 1.18-1.20; FLI ≥ 60, 1.67, 1.65-1.69, P for trend <0.001). The risk of disease-specific mortality including cardiovascular disease (CVD), cancer, respiratory disease and liver disease, linearly increased as the FLI score became higher (HR, 95% CI: FLI 30-59, 1.18, 1.16-1.20, FLI ≥ 60: 1.61, 1.56-1.65 for CVD; FLI 30-59, 1.13, 1.11-1.14, FLI ≥ 60, 1.41, 1.38-1.44 for cancer; FLI 30-59, 1.26, 1.22-1.29, FLI ≥ 60, 1.96, 1.88-2.05 for respiratory disease, FLI 30-59, 2.29, 2.21-2.38, FLI ≥ 60, 5.57, 5.31-5.85 for liver disease). The risk of all-cause mortality increased as the FLI score became higher across all the body mass index groups, and the greatest risk was observed in those who were underweight (HR, 95% CI = 2.43, 2.09-2.82 in FLI ≥ 60).

CONCLUSION

FLI may serve as a prognostic indicator of death and a high FLI is associated with a poor prognosis particularly in the underweight group.

The Obesity Paradox in Chronic Heart Disease and Chronic Obstructive Pulmonary Disease

Obesity in recent years has become an epidemic. A high body mass index (BMI) is one of today's most crucial population health indicators. BMI does not directly quantify body fat but correlates well with easier body fat measurements. Like smoking, obesity impacts multiple organ systems and is a major modifiable risk factor for countless diseases. Despite this, reports have emerged that obesity positively impacts the prognosis of patients with chronic illnesses such as chronic heart failure (CHF) and chronic obstructive pulmonary disease (COPD), a phenomenon known as the Obesity Paradox. This article attempts to explain and summarize this phenomenon.

As it stands, two theories explain this paradox. The muscle mass hypothesis states that obese patients are better adapted to tide through acute exacerbations due to increased reserve because of greater muscle mass. The other theory focuses on brown adipose tissue and its anti-inflammatory effects on the body.

We performed a literature review on research articles published in English from 1983 to the present in the following databases - PubMed, Elsevier, and Google Scholar. The following search strings and Medical Subject Headings (MeSH) terms were used: "Obesity," "Heart Failure," "COPD," and "Cardio-Respiratory Fitness." In this review, we looked at the obesity paradox in Heart Failure and COPD. We summarized the current literature on the Obesity Paradox and reviewed its relationship with Cardio-Respiratory Fitness.

Role of Short-Chain Fatty Acids Produced by Gut Microbiota in Innate Lung Immunity and Pathogenesis of the Heterogeneous Course of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a widespread socially significant disease. The development of COPD involves the innate immune system. Interestingly, the regulation of the innate lung immune system is related to the gut microbiota. This connection is due to the production by gut microorganisms of short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate. Nutritional disturbances and changes in the structure of the intestinal microbiota lead to a decrease in SCFAs production and their effect on pulmonary immunity. The presence of a metabolic and immune axis linking the lungs and gut plays an important role in the pathogenesis of COPD. In addition, the nature of nutrition and SCFAs may participate in the development of the clinically heterogeneous course of COPD.

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.

Balance impairment and lower limbs strength in patients with COPD who fell in the previous year

Fall-related causes in patients with COPD might be associated to functional balance impairments and greater disease severity. We aimed to evaluate the reasons for falls in patients with COPD who had presented any fall during the previous year. This is a cross-sectional study. All COPD's GOLD classifications (mild, moderate, severe, and very severe) patients were recruited. In order to participate, patients ought to be clinically stable and without any exacerbation within 30 days prior to study entry. History of falls was self-reported by patients through an interview. Pre and post bronchodilator (salbutamol 400 μg) spirometry was performed. All patients accomplished postural balance tests such as the Berg Balance Scale, Falls Efficacy Scale-International, Time up and Go, Functional Reach test, Tinetti test and Chalder Scale; furthermore, lower limbs muscle strength (muscle dynamometry) and the COPD Assessment Test (CAT) were assessed. Ninety-six patients with COPD were evaluated and divided into two groups stratified according to any positive history of falls in the previous year. Patients with COPD who had any fall in the previous year presented older age (p=0.01), higher BMI (p=0.04) and worse pulmonary function than those who did not fall. The risk of falls was increased in patients with lower muscle strength in the lower limbs (OR 2.9, CI 95%;1.6 to 3.9), age greater than 65 years (OR 2.7, CI 95%;1.3 to 3.4), BMI greater than 28.8 kg/m2 (OR 3.2, CI 95%;1.1 to 5.6), very severe airway obstruction (OR 3.9, CI 95%;2.2 to 3.9) and fatigue (OR 3.2, CI 95%;1.5 to 5.3). Impaired body balance, reduced lower limb strength, disease severity, presence of fatigue and elevated BMI are important factors for falls in patients with COPD.

Bee bread mitigates downregulation of steroidogenic genes, decreased spermatogenesis, and epididymal oxidative stress in male rats fed with high-fat diet

The pituitary-gonadal axis plays an important role in steroidogenesis and spermatogenesis, and by extension, fertility. The aim of this study was to investigate the protective role of bee bread, a natural bee product, against obesity-induced decreases in steroidogenesis and spermatogenesis. Thirty-two adult male Sprague-Dawley rats weighing between 200 and 300 g were divided into four groups (n = 8/group), namely: normal control (NC), high-fat diet (HFD), HFD plus bee bread administered concurrently for 12 wk (HFD + B), HFD plus orlistat administered concurrently for 12 wk (HFD + O) groups. Bee bread (0.5 g/kg) or orlistat (10 mg/kg/day) was suspended in distilled water and given by oral gavage daily for 12 wk. Levels of follicle-stimulating hormone, luteinizing hormone, testosterone, and adiponectin, as well as sperm count, motility, viability, normal morphology, and epididymal antioxidants decreased, whereas levels of leptin, malondialdehyde, and sperm nDNA fragmentation increased significantly in the HFD group relative to the NC group. There were significant decreases in the testicular mRNA transcript levels of androgen receptor, luteinizing hormone receptor, steroidogenic acute regulatory protein, cytochrome P450 enzyme, 3β-hydroxysteroid dehydrogenase (HSD) and 17β-HSD in the testes of the HFD group. Furthermore, mount, intromission and ejaculatory latencies increased, and penile cGMP level decreased significantly in the HFD group. Supplementation with bee bread significantly reduced leptin level and increased adiponectin level, enhanced sperm parameters and reduced sperm nDNA fragmentation, upregulated the levels of steroidogenic genes and proteins in HFD-induced obese male rats. Bee bread improved steroidogenesis and spermatogenesis by upregulating steroidogenic genes. Therefore, bee bread may be considered as a potential supplementation to protect against infertility in overweight men or men with obesity.NEW & NOTEWORTHY The high-fat diet utilized in the present study induced obesity in the male rats. Bee bread supplementation mitigated impaired steroidogenesis, spermatogenesis, mating behavior, and fertility potential by counteracting the downregulation of steroidogenic genes, thus increasing testosterone levels and suppressing epididymal oxidative stress. These benefits may be due to the abundance of phenolic and flavonoid compounds in bee bread.

Obesity paradox and heart failure

BACKGROUND

There is scientific consensus that obesity increases the risk of cardiovascular diseases (CVD), including heart failure (HF). However, in CVD, many studies observed greater survival in overweight or class 1 obesity individuals. This counterintuitive observation was termed "obesity paradox" (OP).

OBJECTIVE AND METHODS

This article is a narrative overview of the relationship between OP and CVD, particularly HF. The sources used were MEDLINE/PubMed, CINAHL, EMBASE, and Cochrane Library, from 2001 to 31 May 2020, exception for a 1983 work of historical importance. Studies reporting association and prognostic impact of obesity in HF and the impact of body composition on cardiac structure and myocardial function in obesity were also included in this review. In addition, we examined references from the retrieved articles and explored several related websites. Ultimately, we chose 79 relevant documents. Fifty-three were specifically focused on OP and HF.

RESULTS

In this review, we made a summary of the evidence coming from a series of studies investigating OP. Many of these studies do not take into consideration or underestimate some of the more important morpho-functional variables of patients suffering from HF: among these, body composition and visceral adiposity, sarcopenic obesity, muscle fitness (MF), and cardiorespiratory fitness (CRF). A high body mass index (BMI) represents a risk factor for HF, but it also seems to exert a protective effect under certain circumstances. Fat distribution, lean mass, and cardio fitness could play an essential role in determining the observed differences in the HF population.

CONCLUSION

BMI does not distinguish between the metabolically healthy and metabolically unhealthy obesity. The obesity impact on morbidity and premature mortality can be underestimated and, therefore, may lead to incorrect clinical courses.

LEVEL OF EVIDENCE

Level V, Narrative review.

Challenging the obesity paradox: extreme obesity and COPD mortality in the SUMMIT trial

Populations with COPD demonstrate higher survival in overweight and obese compared with normal weight; the “obesity paradox”. Relationships in less-severe COPD are unclear, as is the impact of cardiovascular risk, and few studies include individuals at extremes of obesity.

 We examined the relationship between body mass index (BMI; defined as underweight: <20 kg·m⁻², normal: 20–25 kg·m⁻², overweight: 25– <30 kg·m⁻², obese class I: 30– <35 kg·m⁻², class II: 35– <40 kg·m⁻² and class III: ≥40 kg·m⁻²), morbidity, and mortality in the SUMMIT trial population (n=16 485), characterised by moderate COPD and heightened cardiovascular risk with a substantial proportion with class III obesity. The association between BMI category and time to event was modelled via proportional hazards (reference normal weight) adjusted for demographics and cardiorespiratory disease.

 Consistent with the paradox, underweight individuals demonstrated higher mortality (hazard ratio (HR) 1.31 (95% CI 1.04–1.64)), with lower mortality among overweight (HR 0.62 (95% CI 0.52–0.73)) and obese class I (HR 0.75 (95% CI 0.62–0.90)). However, mortality increased in obese class III (HR 1.36 (95% CI 1.00–1.86)). Death was primarily attributable to cardiovascular causes.

 Within a large, multinational cohort with moderate COPD and increased cardiovascular risk, the phenomenon of reduced mortality with obesity did not persist at BMI >40 kg·m⁻², suggesting that obesity may not remain protective at the extremes in this population.

In a population with moderate COPD, at heightened cardiovascular risk and containing a substantial proportion of individuals with BMI ≥40 kg/m², BMI and mortality demonstrate a U-shaped (rather than J-shaped) relationshiphttps://bit.ly/3hDztI6

Association between lung function and future risks of diabetes, asthma, myocardial infarction, hypertension and all-cause mortality

BACKGROUND

While forced expiratory volume in 1 s (FEV1) is a hallmark of disease progression in chronic obstructive lung diseases, little is known about the relationship between baseline FEV1 and future risks of other medical conditions.

OBJECTIVE

The aim of this study was to investigate the association between baseline FEV1 and future risks of diabetes, asthma, myocardial infarction, hypertension and all-cause mortality.

METHODS

We used data from the National Health and Nutrition Examination Survey and its Epidemiological Follow-Up Study. Our data provided longitudinal follow-up of the original cohort for up to 12 years. We used two competing risks approaches, the cause-specific hazard model and the Fine-Gray sub-distribution hazard model, to measure the associations between baseline FEV1 and future risks of the outcomes of interest. All models were adjusted for major confounding factors.

RESULTS

The final sample included 3020 participants (mean±sd baseline age 44.64±13.44 years). In the cause-specific hazard model, for every per cent increase in the baseline per cent predicted FEV1, the hazard of the event reduced by 2.5% (HR 0.975; 95% CI 0.958-0.994) for diabetes, 4.3% (HR 0.957; 95% CI 0.932-0.983) for asthma and 1.8% (HR 0.982; 95% CI 0.971-0.992) for all-cause mortality. There was no statistically significant association between baseline per cent predicted FEV1 and future risks of myocardial infarction (HR 0.987; 95% CI 0.970-1.004) and hypertension (HR 0.998; 95% CI 0.992-1.005). Consistent results were observed for the Fine-Gray sub-distribution hazard model.

CONCLUSION

Our data suggest that lower per cent predicted FEV1 values at baseline were significantly associated with higher future risks of diabetes, asthma and all-cause mortality.

Outcomes of Idiopathic Pulmonary Fibrosis Improve with Obesity: A Rural Appalachian Experience

OBJECTIVES

Obesity can be an independent predictor of fibrosis in tissues, including the liver, heart, and skin. We evaluated a rural Appalachian cohort of idiopathic pulmonary fibrosis (IPF) for its relation to obesity.

METHODS

Using American Thoracic Society 2018 diagnostic guidelines, an IPF cohort was systematically identified at an Appalachian academic medical center (2015-2019). The cohort was categorized in subgroups of body mass index (BMI) <30 or BMI ≥30 kg/m². Demographics, clinical variables, and treatment details were collected retrospectively and evaluated for their associations with obesity.

RESULTS

In our IPF cohort (N = 138), a usual interstitial pneumonia pattern was less prevalent in the obese group (n = 49) relative to the nonobese group (69% vs 85%, respectively). The obese group was younger (mean age 73.27 ± 9.12 vs 77.97 ± 9.59 years) and had a higher prevalence of hypertension (90% vs 72%), hyperlipidemia (83% vs 68%), diabetes mellitus (47% vs 25%), sleep-disordered breathing (47% vs 25%), chronic pain disorders (28% vs 15%), and deep vein thrombosis (19% vs 7%). An increased proportion of obese-IPF patients was seen at a tertiary or an interstitial lung disease center, with more surgical lung biopsies performed and incident diagnosis (ie, within 6 months of presentation) assigned. Only a minority of patients underwent lung transplantation (3.6%), all of them from the obese-IPF subgroup. Approximately 30% of the total IPF cohort died, with a lower mortality observed in the obese group (35% vs 20%, P = 0.017). An increasing BMI predicted a better survival in the total IPF cohort (BMI 25-29.9, 20-24.9, and <20 had mortality rates of 20%, 47%, and 75%, respectively; P < 0.001).

CONCLUSIONS

Our study represents a first known effort to develop an IPF cohort in a rural Appalachian region. Although they shared an increased burden of comorbidities, the obese subgroup showed less advanced fibrosis with a lower mortality rate relative to nonobese subgroup, suggesting a potential "obesity paradox" in IPF. The study findings significantly advance our understanding of challenges posed by IPF in a rural population that also suffers from an alarming rate of obesity. We highlight the need for the multidisciplinary management of these patients and prospective studies to better define this complex relation.