Current asthma contributes as much as smoking to chronic bronchitis in middle age: a prospective population-based study

Fixed Airflow Obstruction in Asthma Can Be Identified Early by Low FEF25-75% and is Associated with Environmental Exposure

Purpose

This study aimed to identify environmental risk factors associated with asthmatic fixed airflow obstruction (FAO) and assess the relationship between small airway abnormalities defined by forced expiratory flow at 25-75% (FEF25-75%) and FAO.

Patients and Methods

We analyzed data from 312 han Chinese patients with stable asthma on standard treatment. Low FEF25-75% was defined as post-bronchodilator FEF25-75% z-score <-0.8435, and FAO as post-bronchodilator FEV1/FVC z-score <-1.645. Exposure levels were retrospectively analyzed in relation to FAO risk in asthmatics. Asthmatics were grouped by low FEF25-75% and FAO, and lung function, environmental exposure, daily symptoms, and exacerbations in the previous year were compared cross-sectionally across groups.

Results

In retrospective analyses, pack-years of smoking in male patients (adjusted odd ratio [95% confidence interval] 1.05 [1.03-1.07], P<0.001), biomass exposure for >20 years (2.65 [1.13-6.43], P=0.027), occupational exposure for >10 years (2.01 [1.06-3.86], P=0.035) and occupational exposure for >20 years (2.67 [1.24-5.91], P=0.013) were associated with asthmatic FAO. In cross-sectional analyses, compared with the normal FEF25-75%/ asthmatics without FAO (NON-FAO) group, the low FEF25-75%/ asthmatics with FAO (FAO) group had lower FEV1 z-scores and FEV1/FVC z-scores, more pack-years and years of biomass and occupational exposure, higher Asthma Control Questionnaire-5 and Chronic Obstructive Pulmonary Disease Assessment Test scores, and more frequent exacerbations. The low FEF25-75%/NON-FAO group showed the same trend, but to a lesser extent.

Conclusion

Chronic airway inflammation is not the only driver of asthmatic FAO, and management and treatment targeting environmental risk factors (smoking and biomass and occupational exposures) may slow FAO progression in asthmatics. The FEF25-75% determined by the z-score is a reliable marker of small airway abnormalities, and patients with low FEF25-75% are at greater risk for FAO, requiring more frequent follow-up.

Causal associations between pediatric asthma and united airways disease: a two-sample Mendelian randomization analysis

Background

Prior observational research has indicated a potential link between pediatric asthma and united airways disease (UAD). However, these findings could be subject to confounding factors and reverse causation. Therefore, our study utilizes Mendelian randomization (MR) method to further investigate the causal relationship between pediatric asthma and UAD.

Methods

We conducted a comprehensive two-sample Mendelian randomization (MR) analysis to investigate the association between pediatric asthma and seven groups of UAD, including chronic sinusitis, chronic rhinitis, nasopharyngitis and pharyngitis, chronic diseases of tonsils and adenoids, chronic laryngitis and laryngotracheitis, chronic bronchitis, bronchiectasis, chronic obstructive pulmonary disease (COPD). The present study employed a range of methods for two-sample MR analysis, including inverse variance weighted (IVW), MR-Egger regression, Simple mode, weighted median, and weighted models. The conclusion of the MR analysis primarily relies on the IVW results, while other analytical methods are utilized as supplementary evidence to ensure result robustness in this MR analysis. And sensitivity analyses were conducted, including heterogeneity test, horizontal pleiotropy test, MR-PRESSO test, and leave-one-out analysis to validate the results.

Results

The results of the MR analysis indicate significant causal effects of pediatric asthma on chronic rhinitis, nasopharyngitis and pharyngitis (IVW: OR = 1.15, 95%CI: 1.05-1.26, p-value = 0.003), chronic diseases of tonsils and adenoids (IVW: OR = 1.07, 95%CI: 1.00-1.15, p-value = 0.038), chronic bronchitis (IVW: OR = 1.51, 95%CI: 1.42-1.62, p-value <0.001), bronchiectasis (IVW: OR = 1.51, 95%CI: (1.30-1.75), p-value <0.001), and COPD (IVW: OR = 1.43, 95%CI: 1.34-1.51, p-value <0.001). However, no significant causal association was observed between pediatric asthma and chronic sinusitis (IVW: OR = 1.00, 95%CI: 1.00-1.00, p-value = 0.085), chronic laryngitis and laryngotracheitis (IVW: OR = 1.05, 95%CI: 0.90-1.21, p-value = 0.558).

Conclusion

Our findings support a potential causal relationship between pediatric asthma and UAD, suggesting that pediatric asthma may be a potential risk factor for various UAD.

Chronic Bronchitis in Children and Adults: Definitions, Pathophysiology, Prevalence, Risk Factors, and Consequences

The complex nature of chronic bronchitis (CB) and changing definitions have contributed to challenges in understanding its aetiology and burden. In children, CB is characterised by persistent airway inflammation often linked to bacterial infections and is therefore termed "protracted bacterial bronchitis" (PBB). Longitudinal studies suggest that CB in childhood persists into adulthood in a subgroup. It can also be associated with future chronic respiratory diseases including asthma, bronchiectasis, and chronic obstructive pulmonary disease (COPD). Adult CB is traditionally associated with smoking, occupational exposures, and lower socioeconomic status. The interplay between risk factors, childhood CB, adult CB, and other chronic respiratory diseases is intricate, requiring comprehensive longitudinal studies for a clearer understanding of the natural history of CB across the lifespan. Such longitudinal studies have been scarce to date given the logistic challenges of maintaining them over time. In this review, we summarise current evidence on the evolution of the definitions, pathophysiology, risk factors, and consequences of childhood and adulthood chronic bronchitis.

Childhood 'bronchitis' and respiratory outcomes in middle-age: a prospective cohort study from age 7 to 53 years

BACKGROUND

Chronic bronchitis in childhood is associated with a diagnosis of asthma and/or bronchiectasis a few years later, however, consequences into middle-age are unknown.

OBJECTIVE

To investigate the relationship between childhood bronchitis and respiratory-related health outcomes in middle-age.

DESIGN

Cohort study from age 7 to 53 years.

SETTING

General population of European descent from Tasmania, Australia.

PARTICIPANTS

3202 participants of the age 53-year follow-up (mean age 53, range 51-55) of the Tasmanian Longitudinal Health Study cohort who were born in 1961 and first investigated at age 7 were included in our analysis.

STATISTICAL METHODS

Multivariable linear and logistic regression. The association between parent reported childhood bronchitis up to age 7 and age 53-year lung conditions (n=3202) and lung function (n=2379) were investigated.

RESULTS

Among 3202 participants, 47.5% had one or more episodes of childhood bronchitis, classified according to severity based on the number of episodes and duration as: 'non-recurrent bronchitis' (28.1%); 'recurrent non-protracted bronchitis' (18.1%) and 'recurrent-protracted bronchitis' (1.3%). Age 53 prevalence of doctor-diagnosed asthma and pneumonia (p-trend <0.001) and chronic bronchitis (p-trend=0.07) increased in accordance with childhood bronchitis severities. At age 53, 'recurrent-protracted bronchitis' (the most severe subgroup in childhood) was associated with doctor-diagnosed current asthma (OR 4.54, 95% CI 2.31 to 8.91) doctor-diagnosed pneumonia (OR=2.18 (95% CI 1.00 to 4.74)) and, paradoxically, increased transfer factor for carbon monoxide (z-score +0.51 SD (0.15-0.88)), when compared with no childhood bronchitis.

CONCLUSION

In this cohort born in 1961, one or more episodes of childhood bronchitis was a frequent occurrence. 'Recurrent-protracted bronchitis', while uncommon, was especially linked to multiple respiratory outcomes almost five decades later, including asthma, pneumonia and raised lung gas transfer. These findings provide insights into the natural history of childhood 'bronchitis' into middle-age.

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.

Childhood asthma as a risk factor for adult chronic obstructive pulmonary disease: a systematic review and meta-analysis

Background: Due to the disagreement in studies, the present study performed a systematic review and meta-analysis to investigate the relationship between childhood asthma and the development of chronic obstructive pulmonary disease (COPD) in adulthood.Methods: Literature search was performed in Medline and Embase databases until the end of 2019. Data were recorded as adjusted odds ratio (OR) and 95% confidence interval (95%CI). Analyses were performed on STATA 14.0 and an overall OR was reported. Subgroup analysis was performed to determine the source of heterogeneity.Results: Data from 11 articles were included in the meta-analysis. Overall, the odds of developing adulthood COPD in children with asthma were 3.0 times higher than that in non-asthmatic children (OR = 3.00; 95%CI: 2.25-4.00; p < 0.001). The relationship between childhood asthma and COPD in adulthood was reported somewhat greater in random sampling method studies than consecutive sampling method studies (OR = 2.89; 95% CI: 1.72-4.86; p = 0.001).Conclusion: Asthma in childhood could be considered as an independent risk factor for COPD in adulthood. Since type of study, sampling method, sample size of study and COPD prevalence are the main sources of heterogeneity, further prospective high-quality studies assessing the relationship of childhood asthma and adulthood COPD are recommended to be performed.

Childhood asthma increases respiratory morbidity, but not all-cause mortality in adulthood: The Busselton Health Study

BACKGROUND

Long-term childhood asthma studies that investigate adult outcomes other than lung function are lacking. This study examines the associations of childhood asthma and the occurrence of respiratory events and all-cause mortality in adulthood.

METHODS

A cohort of 4430 school children (aged to 17 years) who attended the Busselton Health Study between 1967 and 1983 were analysed. Self-reported history of asthma was determined using questionnaires. Participants were followed until 2014 for respiratory disease-related events (hospital admissions or death) and all-cause mortality using the Western Australia Data Linkage System. Cox regression models were used to investigate the impact of childhood asthma on respiratory events and all-cause mortality in adulthood. A subgroup of 2153 participants who re-attended a survey in young adulthood was also analysed.

RESULTS

A total of 462 (10%) of the cohort had childhood asthma. During follow-up 791 participants experienced a respiratory event and 140 participants died. Childhood asthma was associated with an increased risk of respiratory events in adulthood (unadjusted HR 1.84, 95% CI 1.52 to 2.23; P < 0.0001). The result remained significant after adjusting for adult-onset asthma, FEV₁, body mass index, smoking, dusty job, hay fever, and respiratory symptoms (adjusted HR 1.68, 95% CI 1.07 to 2.64; P = 0.0247). Childhood asthma was not associated with all-cause mortality in adulthood (unadjusted HR 1.08, 95% CI 0.63 to 1.84; P = 0.7821).

CONCLUSION

Childhood asthma is associated with increased risk of respiratory disease-related hospital admissions and death but not all-cause mortality in adulthood.

Impact of COPD diagnosis timing on clinical and economic outcomes: the ARCTIC observational cohort study

Purpose: Assess the clinical and economic consequences associated with an early versus late diagnosis in patients with COPD. Patients and methods: In a retrospective, observational cohort study, electronic medical record data (2000-2014) were collected from Swedish primary care patients with COPD. COPD indicators (pneumonia, other respiratory diseases, oral corticosteroids, antibiotics for respiratory infections, prescribed drugs for respiratory symptoms, lung function measurement) registered prior to diagnosis were applied to categorize patients into those receiving early (2 or less indicators) or late diagnosis (3 or more indicators registered >90 days preceding a COPD diagnosis). Outcome measures included annual rate of and time to first exacerbation, mortality risk, prevalence of comorbidities and health care utilization. Results: More patients with late diagnosis (n=8827) than with early diagnosis (n=3870) had a recent comorbid diagnosis of asthma (22.0% vs 3.9%; P<0.0001). Compared with early diagnosis, patients with late diagnosis had a higher exacerbation rate (hazard ratio [HR] 1.89, 95% confidence interval [CI]: 1.83-1.96; P<0.0001) and shorter time to first exacerbation (HR 1.61, 95% CI: 1.54-1.69; P<0.0001). Mortality was not different between groups overall but higher for late versus early diagnosis, after excluding patients with past asthma diagnosis (HR 1.10, 95% CI: 1.02-1.18; P=0.0095). Late diagnosis was also associated with higher direct costs than early diagnosis. Conclusion: Late COPD diagnosis is associated with higher exacerbation rate and increased comorbidities and costs compared with early diagnosis. The study highlights the need for accurate diagnosis of COPD in primary care in order to reduce exacerbations and the economic burden of COPD.

Epidemiology of chronic airway disease: results from a cross-sectional survey in Beijing, China

Background

Although the epidemiology of chronic airway disease (CAD) has been investigated in several population-based studies, the findings of these studies are diverse. We aimed to investigate the prevalence of CAD and its associated factors in urban northern China.

Methods

A cross-sectional study was conducted among 29,359 Chinese adults aged ≥20 years. All participants were randomly recruited from two urban communities in Beijing and asked to complete a self-administered questionnaire that enquired about the demographic characteristics as well as the diagnosis of CAD and CAD-related symptoms.

Results

In all, 26,166 participants completed the questionnaire, with the response rate being 89.1%. The prevalence of diagnosed CAD was 9.0% among men and 7.2% among women, with a total prevalence of 8.1%. Furthermore, 11.5% of the investigated subjects had CAD-related symptoms. Women had a lower risk of developing wheezing, cough, dyspnea, and diagnosed CAD than men (P<0.05). The frequency of CAD-related symptoms and diagnosed CAD was greater among elderly persons than among those who were younger (P<0.01). Subjects with a smoking habit were more susceptible to CAD-related symptoms and diagnosed CAD (P<0.01). Additionally, individuals with CAD-related symptoms were more likely to be diagnosed with CAD, compared to those without these symptoms (P<0.01).

Conclusions

CAD is a common respiratory disease in urban northern China. Female gender might be a protective factor against CAD, while age and smoking are risk factors for the disease.

The outcome and the influencing factors of the age of onset in post-mortem of chronic bronchitis patients: a retrospective study

Purpose

Chronic bronchitis is thought to occur in elderly patients, and smoking seems to be an important risk factor. The outcomes related to the age of onset in patients with chronic bronchitis are still unclear.

Patients and methods

A retrospective study was conducted on deceased patients whose diagnosis included bronchitis from 2010 to 2016. Patients were separated into two groups according to the age of onset (Group I, age ≤50 years old; Group II, age >50 years old). Information regarding disease course, smoking history, death age, number of admissions per year, Hugh Jones Index, and self-reported comorbidities of the patients was recorded.

Results

The courses of chronic cough and sputum were 33.38±7.73 years and 14.44±8.60 years in Group I and Group II, respectively (p<0.05). The death ages of Group I and Group II were 77.65±7.87 years and 84.69±6.67 years, respectively (p<0.05). There was a significant negative correlation between the number of hospital admissions per year and the age of onset. The age of onset was negatively associated with daily smoking count (r=−0.210) and total smoking count (r=−0.146). In Group I, there were fewer cases of coronary heart disease (OR =0.41 [0.24–0.71]), neurological diseases (OR =0.48 [0.24–0.97]), and total comorbidities (OR =0.67 [0.54–0.85]) than in Group II.

Conclusion

Patients with early onset chronic bronchitis had a longer history, younger death age, poorer health status, and lower incidence of comorbidities.