Effects of obesity on pulmonary function considering the transition from obstructive to restrictive pattern from childhood to young adulthood

Interactions of physical activity and lung function on cognitive health in older adults: Joint association and mediation analysis

BACKGROUND

Maintaining cognitive health in old adults has become a significant public health challenge, with lung function and physical activity (PA) as essential modifiable factors. However, the joint and mediation effects of these two factors with cognition remain unclear.

OBJECTIVES

This study assesses the joint association and mediation effects of lung function and PA with cognition.

DESIGN, SETTING, AND PARTICIPANTS

We utilized cross-sectional data from the 2011-2012 U.S. National Health and Nutrition Examination Survey, including adults aged 60-79 assessed for lung function, PA, and cognition.

MAIN OUTCOMES AND MEASURES

Lung function included forced expiratory volume in one second (FEV1), forced vital capacity (FVC), peak expiratory flow (PEF) and FEV1/FVC. PA was assessed using the Global Physical Activity Questionnaire, covering occupational PA (OPA), transportation-related PA (TPA), and leisure-time PA (LTPA). Cognition was evaluated using the Digit Symbol Substitution Test, Animal Fluency Test, Delayed Recall Test and Immediate Recall Test. Weighted multiple linear regression models were used to analyze the separate and joint associations of lung function and PA with cognition, while also exploring potential mediation effects between these factors.

RESULTS

A total of 927 participants, representing 35,525,782 U.S. residents, were included, with a weighted median age of 65 (IQR, 63 -71) years, and 53.6 % were female. The results showed a significant positive association between lung function and cognitive function, with FEV1, FVC, and PEF all positively correlated, while the FEV1/FVC showed no notable link. Further analysis revealed the best cognitive performance observed in participants with active LTPA and the highest quartile of lung function, indicating a joint association of LTPA and lung function with cognition. Mediation analysis indicated that lung function mediated 24.1 % (95 %CI: 6.3 % - 47.0 %, P = 0.03) of the relationship between LTPA and cognition, while cognition mediated 10.2 % (95 %CI: 0.5 % - 27.0 %, P = 0.04) of the relationship between LTPA and lung function.

CONCLUSION

Lung function and cognition may have a bidirectional relationship. The combination of active LTPA and better lung function was strongly associated with higher cognition, highlighting the need to strengthen exercise focused on lung function to maintain cognitive health in older adults.

Effects of Obesity and Sex on Supine Functional Residual Capacity and Expiratory Flow Limitation in Children

INTRODUCTION

Childhood obesity is associated with a higher risk of sleep-disordered breathing, but our understanding of the underlying physiologic mechanisms is limited. This study investigated the effects of obesity on lung volumes, expiratory flow limitation (EFL), and respiratory symptoms in the supine position.

METHODS

Ninety-four children (8-12 years old, n = 58 with obesity and n = 36 without obesity) underwent lung volume and EFL measurements in the seated and supine positions in this repeated-measures cross-sectional study. Children without obesity underwent an additional condition where either a 2.3 kg (n = 26) or 5.0 kg (n = 8) mass was placed on their abdomen to simulate obesity. Ratings of perceived breathlessness (RPB) were recorded.

RESULTS

Functional residual capacity (FRC) in the supine when compared with the seated posture decreased more so in children without obesity (43.9 ± 1.0 vs. 34.4 ± 1.0% total lung capacity [TLC]) compared with children with obesity (35.5 ± 0.8 vs. 29.6 ± 0.8% TLC; p = 0.0048 group*posture). EFL in the supine position was present in 17% of children with obesity compared with 6% of children without obesity (p = 0.1218). In children without obesity, mass-loading with 5.0 kg produced further reductions in FRC (seated: 45.0 ± 1.7% TLC; supine: 36.7 ± 1.7% TLC; supine+5.0 kg: 29.4 ± 1.7% TLC; p = 0.0087 seated vs. supine+ and p = 0.0178 supine vs. supine + ) and an increase in RPB (seated: 0.38 ± 0.24; supine: 0.42 ± 0.24; supine+5.0 kg: 1.25 ± 0.27; p = 0.0002 seated vs. supine+ and p = 0.0001 supine vs. supine + ).

CONCLUSIONS

Children with obesity breathe at significantly lower lung volumes while supine, increasing the risk of EFL. A better physiologic understanding of the mechanical effects of obesity could potentially improve the management of sleep-related symptoms among children with obesity.

Forced vital capacity and body mass index of Xinjiang children and adolescents: an analysis based on seven successive national surveys, 1985-2014

BACKGROUND

Pulmonary function is very important for the healthy development of children and adolescents. However, fewer studies have been conducted on pulmonary function trends in children and adolescents in remote areas. The aim of this study was to estimate the forced vital capacity (FVC) trend and its relationship with body mass index (BMI) among young people in Xinjiang during 1985-2014 using data from seven successive national surveys.

METHODS

A total of 19,449 Xinjiang children and adolescents aged 7-18 years were extracted from the Chinese National Survey on Students' Constitution and Health. Height, weight, and FVC were measured repeatedly in each survey. FVC comparisons between adjacent surveys by age and sex were conducted by nonparametric Kruskal-Wallis after Kolmogorov-Smirnov of normality. One-way ANOVA and least significant difference(LSD) method was used to compare differences in FVC levels of Xinjiang children and adolescents with different BMI. The relationship between BMI and FVC was investigated using a nonlinear regression model.

RESULTS

The FVC levels of Xinjiang children and adolescents peaked in 2000, with overall FVC levels being 8.7% higher in 2000 than in 1985. Since then, a substantial decline occurred, contrasting to 2000, with FVC levels decreasing by 27% in 2014, which was still lower than that in 1985 by 20.73%. The proportion of overnutrition boys increased from 0.2% in 1985 to 22.1% in 2014, and girls from 0.5% in 1985 to 14.5% in 2014. An inverted U-shape association between FVC and BMI values was obtained for Xinjiang children and adolescents.

CONCLUSIONS

Targeted measures should be carried out in schools to control BMI levels to ensure good lung function in children and adolescents in Xinjiang. Future studies should pay more attention to other factors affecting FVC, such as dietary behaviour, physical activity, and racial differences among children and adolescents.

Risk factors for postoperative pulmonary complications in elderly patients undergoing video-assisted thoracoscopic surgery lobectomy under general anesthesia: a retrospective study

BACKGROUND

The objective of this study is to identify and evaluate the risk factors associated with the development of postoperative pulmonary complications (PPCs) in elderly patients undergoing video-assisted thoracoscopic surgery lobectomy under general anesthesia.

METHODS

The retrospective study consecutively included elderly patients (≥ 70 years old) who underwent thoracoscopic lobectomy at Xuanwu Hospital of Capital Medical University from January 1, 2018 to August 31, 2023. The demographic characteristics, the preoperative, intraoperative and postoperative parameters were collected and analyzed using multivariate logistic regression to identify the prediction of risk factors for PPCs.

RESULTS

322 patients were included for analysis, and 115 patients (35.7%) developed PPCs. Multifactorial regression analysis showed that ASA ≥ III (P = 0.006, 95% CI: 1.230 ∼ 3.532), duration of one-lung ventilation (P = 0.033, 95% CI: 1.069 ∼ 4.867), smoking (P = 0.027, 95% CI: 1.072 ∼ 3.194) and COPD (P = 0.015, 95% CI: 1.332 ∼ 13.716) are independent risk factors for PPCs after thoracoscopic lobectomy in elderly patients.

CONCLUSION

Risk factors for PPCs are ASA ≥ III, duration of one-lung ventilation, smoking and COPD in elderly patients over 70 years old undergoing thoracoscopic lobectomy. It is necessary to pay special attention to these patients to help optimize the allocation of resources and enhance preventive efforts.

Relationship between FEV1/FVC and age in children with asthma

INTRODUCTION

Forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) normally decreases through childhood, increases briefly during early adolescence, and then declines throughout life. The physiology behind this temporary increase during early adolescence is not well understood. The objective of this study was to determine if this pattern occurs in children with asthma.

DESIGN

Single-center, cross-sectional, retrospective analysis of pulmonary function tests obtained over a 5-year period in children 5-18 years of age with persistent asthma.

RESULTS

A total of 1793 patients satisfied all inclusion and exclusion criteria. The mean age (±SD) was 10.4 ± 3.8 years. Forty-eight percent were female. Mean FEV1/FVC was 0.83 ± 0.09. FEV1/FVC was lower at 5 years of age than in healthy children, declined from age 5 to 11 by 5.7% compared to 7.3% in healthy girls, and 5.8% compared to 9.4% in healthy boys. FEV1/FVC increased in early adolescence, but at age 16, was 5.6% lower in male children compared to healthy children, and 5.4% lower in females. The ratio was lower in obese children at all ages but demonstrated the same curvilinear shape as healthy children. In absolute terms, FEV1 grew proportionately more than FVC during early adolescence, so the ratio of FEV1/FVC increased during that period. The curvilinear shape of the curve remained in postbronchodilator testing, though significantly blunted.

CONCLUSIONS

FEV1/FVC is lower in children with persistent asthma than healthy children, but the "Shepherd's Hook" pattern is preserved. This was true in obese patients with asthma, although their FEV1/FVC ratios were lower throughout all stages of childhood and adolescence.

Obstructive and restrictive spirometry from school age to adulthood: three birth cohort studies

Background

Spirometric obstruction and restriction are two patterns of impaired lung function which are predictive of poor health. We investigated the development of these phenotypes and their transitions through childhood to early adulthood.

Methods

In this study, we analysed pooled data from three UK population-based birth cohorts established between 1989 and 1995. We applied descriptive statistics, regression modelling and data-driven modelling to data from three population-based birth cohorts with at least three spirometry measures from childhood to adulthood (mid-school: 8-10 years, n = 8404; adolescence: 15-18, n = 5764; and early adulthood: 20-26, n = 4680). Participants were assigned to normal, restrictive, and obstructive spirometry based on adjusted regression residuals. We considered two transitions: from 8-10 to 15-18 and from 15-18 to 20-26 years.

Findings

Obstructive phenotype was observed in ∼10%, and restrictive in ∼9%. A substantial proportion of children with impaired lung function in school age (between one third in obstructive and a half in restricted phenotype) improved and achieved normal and stable lung function to early adulthood. Of those with normal lung function in school-age, <5% declined to adulthood. Underweight restrictive and obese obstructive participants were less likely to transit to normal. Maternal smoking during pregnancy and current asthma diagnosis increased the risk of persistent obstruction and worsening. Significant associate of worsening in restrictive phenotypes was lower BMI at the first lung function assessment. Data-driven methodologies identified similar risk factors for obstructive and restrictive clusters.

Interpretation

The worsening and improvement in obstructive and restrictive spirometry were observed at all ages. Maintaining optimal weight during childhood and reducing maternal smoking during pregnancy may reduce spirometry obstruction and restriction and improve lung function.

Funding

MRC Grant MR/S025340/1.

Obesity-related asthma in children and adolescents

There is substantial epidemiological and experimental evidence of an obesity-related asthma phenotype. Compared to children of healthy weight, children with obesity are at higher risk of asthma. Children with obesity who have asthma have greater severity and poorer control of their asthma symptoms, more frequent asthma exacerbations, and overall lower asthma-related quality of life than children with asthma who have a healthy weight. In this Review, we examine some of the latest evidence on the characteristics of this phenotype and its main underlying mechanisms, including genetics and genomics, changes in airway mechanics and lung function, sex hormone differences, alterations in immune responses, systemic and airway inflammation, metabolic dysregulation, and modifications in the microbiome. We also review current recommendations for the treatment of these children, including in the management of their asthma, and current evidence for weight loss interventions. We then discuss initial evidence for potential novel therapeutic approaches, such as dietary modifications and supplements, antidiabetic medications, and statins. Finally, we identify knowledge gaps and future directions to improve our understanding of asthma in children with obesity, and to improve outcomes in these susceptible children. We highlight important needs, such as designing paediatric-specific studies, implementing large multicentric trials with standardised interventions and outcomes, and including racial and ethnic groups along with other under-represented populations that are particularly affected by obesity and asthma.

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.

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.

Differences in Inflammatory Cytokine Profile in Obesity-Associated Asthma: Effects of Weight Loss

Obesity and asthma are associated with systemic inflammation maintained by mediators released by adipose tissue and lung. This study investigated the inflammatory serum mediator profile in obese subjects (O) (n = 35), non-obese asthma (NOA) patients (n = 14), obese asthmatics (OA) (n = 21) and healthy controls (HC) (n = 33). The effect of weight loss after bariatric surgery (BS) was examined in 10 OA and 31 O subjects. We analyzed serum markers including leptin, adiponectin, TGF-β1, TNFR2, MCP-1, ezrin, YKL-40, ST2, IL-5, IL-9, and IL-18. Compared with HC subjects, the O group showed increased levels of leptin, TGF-β1, TNFR2, MCP-1, ezrin, YKL-40, and ST2; the OA group presented increased levels of MCP-1, ezrin, YKL-40, and IL-18, and the NOA group had increased levels of ezrin, YKL-40, IL-5, and IL-18. The higher adiponectin/leptin ratio in NOA with respect to OA subjects was the only significant difference between the two groups. IL-9 was the only cytokine with significantly higher levels in OA with respect to O subjects. TNFR2, ezrin, MCP-1, and IL-18 concentrations significantly decreased in O subjects after BS. O, OA, and NOA showed distinct patterns of systemic inflammation. Leptin and adiponectin are regulated in asthma by obesity-dependent and -independent mechanisms. Combination of asthma and obesity does not result in significant additive effects on circulating cytokine levels.