History of Asthma From Childhood and Arterial Stiffness in Asymptomatic Young Adults: The Bogalusa Heart Study

An analysis of exogenous harmful substance exposure as risk factors for COPD and hypertension co-morbidity using PSM

Background

Some occupational and environmental exposures could increase the risk of chronic obstructive pulmonary disease (COPD) and hypertension in various work and living environments. However, the effect of exposure to multiple exogenous harmful substances on COPD and hypertension co-morbidities remains unclear.

Methods

Participants were selected from eight hospitals in five provinces in China using a multistage cluster sampling procedure. Participants' demographic, exposure, and disease information were collected through questionnaires, spirometry, and blood pressure examinations. Demographic data were used as matching factors, and 1:1 matching between the exposed and non-exposed groups was performed by employing propensity score matching (PSM) to minimize the influence on the results. A one-way chi-squared analysis and multifactorial logistic regression were used to analyze the association between the exposure to exogenous harmful substances (metals and their compound dust, inorganic mineral dust, organic chemicals, and livestock by-products) and the co-morbidity of COPD and hypertension.

Results

There were 6,610 eligible participants in the final analysis, of whom 2,045 (30.9%) were exposed to exogenous harmful substances. The prevalence of co-morbidities of COPD and hypertension (6.0%) in the exposure group was higher than their prevalence in the total population (4.6%). After PSM, exogenous harmful substance exposure was found to be a risk factor for the co-morbidity of COPD and hypertension [odds ratio (OR) = 1.347, 95% confidence interval (CI): 1.011-1.794], which was not statistically significant before PSM (OR = 1.094, 95% CI: 0.852-1.405). Meanwhile, the results of different outcomes showed that the association between hypertension and exogenous harmful substance exposure was not statistically significant (OR = 0.965, 95% CI: 0.846-1.101). Smoking (OR = 4.702, 95% CI: 3.321-6.656), history of a respiratory disease during childhood (OR = 2.830, 95% CI: 1.600-5.006), and history of respiratory symptoms (OR = 1.897, 95% CI: 1.331-2.704) were also identified as risk factors for the co-morbidity of COPD and hypertension.

Conclusion

The distribution of exogenous harmful substance exposure varies in the population, and the prevalence of co-morbidities is generally higher in susceptible populations. Exposure to exogenous harmful substances was found to be a key risk factor after adjusting for demographic confounders.

Systemic Inflammation in Asthma: What Are the Risks and Impacts Outside the Airway?

Airway inflammation in asthma has been well recognized for several decades, with general agreement on its role in asthma pathogenesis, symptoms, propensity toward exacerbation, and decline in lung function. This has led to universal recommendation in asthma management guidelines to incorporate the use of inhaled corticosteroid as an anti-inflammatory therapy for all patients with persistent asthma symptoms. However, there has been limited attention paid to the presence and potential impact of systemic inflammation in asthma. Accumulating evidence from epidemiological observations and cohort studies points to a host of downstream organ dysfunction in asthma especially among patients with longstanding or more severe disease, frequent exacerbations, and underlying risk factors for organ dysfunction. Most studies to date have focused on cognitive impairment, depression/anxiety, metabolic syndrome, and cardiovascular abnormalities. In this review, we summarize some of the evidence demonstrating these abnormalities and highlight the proposed mechanisms and potential benefits of treatment in limiting these extrapulmonary abnormalities in patients with asthma. The goal of this commentary is to raise awareness of the importance of recognizing potential extrapulmonary conditions associated with systemic inflammation of asthma. This area of treatment of patients with asthma is a large unmet need.

Asthma as a Systemic Disease: Cardiovascular Effects Associated with Asthma

Asthma and cardiovascular disease (CVD) pose significant public health burdens. Airway inflammation is central to asthma pathophysiology and systemic inflammation, which occurs in asthma, is central to CVD pathophysiology. Numerous robust epidemiological studies have demonstrated deleterious systemic cardiovascular effects associated with the asthma syndrome. The cardiovascular effects associated with asthma include arterial injury, atherosclerotic CVD events, atrial fibrillation, and hypertension. Asthma is a heterogeneous disease, however, and the risk of CVD is not homogeneous across the various clinical phenotypes and molecular endotypes, highlighting prior inconsistent associations of asthma and its subtypes with various forms of CVD. The mechanistic underpinnings of the increased CVD risk in asthma remain multifactorial and undefined. Collectively, this supports the need for a precision approach in the identification of individuals with asthma who remain at elevated risk of development of cardiovascular diseases to guide both diagnostic and preventive interventions to decrease CVD risk among individuals living with asthma.

Childhood asthma and cardiovascular morbidity and mortality in adulthood: The Busselton Health Study

BACKGROUND

Long-term childhood asthma studies that investigate adult outcomes other than respiratory morbidity are lacking. This study examines the associations of childhood asthma and the occurrence of cardiovascular disease (CVD) events and mortality in adulthood.

METHODS

A cohort of 4430 school children (aged 17 years) who attended the Busselton Health Study between 1967 and 1983 were analyzed. Self-reported history of doctor-diagnosed asthma was determined based on the questionnaire. Subsequent CVD events (hospital admissions or death) up to 2014 were identified using the Western Australia Data Linkage System. Cox regression models were used to investigate the impact of childhood asthma on CVD events and mortality in adulthood. A subgroup of 2153 participants who re-attended a survey in young adulthood was also analyzed.

RESULTS

A total of 462 (10%) of the cohort had childhood asthma. During follow-up, 867 participants experienced a CVD event and 22 participants died from CVD. Childhood asthma was not associated with the risk of CVD events in adulthood (HR, 1.12; 95% CI: 0.91-1.39; p = .2833) and this persisted after adjustment for confounders. Childhood asthma was not associated with coronary heart disease events (HR, 0.72; 95% CI: 0.40-1.30; p = .2761), heart failure events (HR, 0.55; 95% CI: 0.07-4.13; p = .5604) or CVD mortality (HR, 0.91; 95% CI: 0.21-3.89; p = .8987) in adulthood.

CONCLUSION

Childhood asthma is not associated with the risk of CVD events and mortality in adulthood.

The Gut/Lung Microbiome Axis in Obesity, Asthma, and Bariatric Surgery: A Literature Review

Mounting evidence suggests that obesity, parameters of metabolic syndrome, and asthma are significantly associated. Interestingly, these conditions are also associated with microbiome dysbiosis, notably in the airway microbiome for patients with asthma and in the gut microbiome for patients with obesity and/or metabolic syndrome. Considering that improvements in asthma control, lung function, and airway hyperresponsiveness are often reported after bariatric surgery, this review investigated the potential role of bacterial gut and airway microbiome changes after bariatric surgery in ameliorating asthma symptoms. Rapid and persistent gut microbiota alterations were reported following surgery, some of which can be sustained for years. The gut microbiome is thought to modulate airway cellular responses via short-chain fatty acids and inflammatory mediators, such that increased propionate and butyrate levels following surgery may aid in reducing asthma symptoms. In addition, increased prevalence of Akkermansia muciniphila after Roux-en-Y gastric bypass and sleeve gastrectomy may confer protection against airway hyperreactivity and inflammation. Metabolic syndrome parameters also improved following bariatric surgery, and whether weight-loss-independent metabolic changes affect airway processes and asthma pathobiology merits further research. Fulfilling knowledge gaps outlined in this review could facilitate the development of new therapeutic options for patients with obesity and asthma.