Inhaled steroid/tobacco smoke particle interactions: a new light on steroid resistance

Oxidative Stress-Derived Mitochondrial Dysfunction in Chronic Obstructive Pulmonary Disease: A Concise Review

Chronic obstructive pulmonary disease (COPD) is a progressive and disabling disorder marked by airflow limitation and extensive destruction of lung parenchyma. Cigarette smoke is the major risk factor for COPD development and has been associated with increased oxidant burden on multiple cell types in the lungs. Elevated levels of reactive oxygen species (ROS) may significantly affect expression of biological molecules, signaling pathways, and function of antioxidant defenses. Although inflammatory cells, such as neutrophils and macrophages, contribute to the release of large quantities of ROS, mitochondrial dysfunction plays a critical role in ROS production due to oxidative phosphorylation. Although mitochondria are dynamic organelles, excess oxidative stress is able to alter mitochondrial function, morphology, and RNA and protein content. Indeed, mitochondria may change their shape by undergoing fusion (regulated by mitofusin 1, mitofusin 2, and optic atrophy 1 proteins) and fission (regulated by dynamin-related protein 1), which are essential processes to maintain a healthy and functional mitochondrial network. Cigarette smoke can induce mitochondrial hyperfusion, thus reducing mitochondrial quality control and cellular stress resistance. Furthermore, diminished levels of enzymes involved in the mitophagy process, such as Parkin (a ubiquitin ligase E3) and the PTEN-induced putative kinase 1 (PINK1), are commonly observed in COPD and correlate directly with faulty removal of dysfunctional mitochondria and consequent cell senescence in this disorder. In this review, we highlight the main mechanisms for the regulation of mitochondrial quality and how they are affected by oxidative stress during COPD development and progression.

Effective management of adult patients with asthma

Asthma is a chronic respiratory condition that can affect people of all ages. Globally, asthma is one of the most common non-communicable diseases and is associated with significant personal, financial and societal costs. In some cases, asthma can be fatal, although many fatalities would have been preventable with appropriate management. People with asthma often underestimate the effects of their symptoms, and nurses should develop their knowledge and skills so that they can provide appropriate management advice. This article outlines the causes of asthma and its symptoms. It also explains the interventions used in the management of this condition, including medicines, patient education, appropriate lifestyle changes and referral to specialist services.

Impact of smoking status on the efficacy of inhaled corticosteroids in chronic obstructive pulmonary disease: a systematic review

OBJECTIVES

Inhaled corticosteroids (ICS) reduce exacerbation rates and the decline in lung function in people with chronic obstructive pulmonary disease (COPD). There is evidence that smoking causes 'steroid resistance' and thus reduces the effect of ICS. This systematic review aimed to investigate the effect of smoking on efficacy of ICS in COPD in terms of lung function and exacerbation rates.

DESIGN

Systematic review.

DATA SOURCES

An electronic database search of PubMed, Ovid MEDLINE, Ovid Embase and Cochrane Library (January 2000 to January 2020).

ELIGIBILITY CRITERIA

Fully published randomised controlled trials (RCTs), in the English language, evaluating the use of ICS in COPD adults that stratified the participants by smoking status. Trials that included participants with asthma, lung cancer and pneumonia were excluded. The primary outcome measures were changes in lung function and yearly exacerbation rates.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted data and assessed risk of bias using the Cochrane Collaboration's tool.

RESULTS

Seven studies were identified. Four trials (17 892 participants) recorded change in forced expiratory volume in one second (FEV₁) from baseline to up to 30 months after starting treatment. Heavier smokers (>36 pack years) using ICS had a greater decline in FEV₁ that ranged from -22 mL to -75 mL in comparison to lighter smokers. Smokers using ICS had mixed results in FEV₁ change: -8 mL to +77 mL in comparison to ex-smokers. Four trials (21 270 participants) recorded difference in COPD exacerbation rates at 52 weeks. The rate ratios favoured more exacerbations in ICS users who were current or heavier smokers than those who were ex-smokers or lighter smokers (0.81 to 0.99 vs 0.92 to 1.29).

CONCLUSIONS

In COPD, heavier or current smokers do not gain the same benefit from ICS use on lung function and exacerbation rates as lighter or ex-smokers do, however effects may not be clinically important.

PROSPERO REGISTRATION NUMBER

CRD42019121833.

The relationship between second-hand smoke and wheezing in infants from Córdoba, Argentina

BACKGROUND

Wheezing constitutes a common respiratory symptom in children, and several risk factors have been associated with the prevalence of recurrent wheezing (RW) and its severity, especially viral respiratory infections and second-hand smoke (SHS) exposure.

OBJECTIVE

To analyze the relationship between smoking patterns in the home and wheezing, in infants from the city of Córdoba, Argentina, during their first year of life.

METHODS

Parents of infants were invited to complete a standardized questionnaire voluntarily and anonymously (WQ-P1-EISL). Wheezing in the first 12 months of life was classified as occasional wheezing (OW) when having one or two episodes during the first 12 months of life; recurrent wheezing (RW) if having three or more, and more frequent wheezing (MFW) ≥6 episodes.

RESULTS

409 infants (39.0%) had one or more episodes of wheezing in the first 12 months. Of these, 214 infants (52.3%) presented occasional wheezing (OW), 135 (33%) had recurrent wheezing (RW), and 60 (14.7%) more frequent wheezing (MFW). SHS was significantly related to MFW, especially if the mother smoked (OR=2.7; IC 95%: 1.4-5.18; p=0.0009) or if she smoked during pregnancy (OR=4; IC 95%: 1.8-8.5; p=0.0001). This group of MFW was also associated with SHS as well as having been to the emergency room for wheezing (40.87%, p=0.0056).

CONCLUSION

The results indicate that second-hand tobacco smoke is a significant risk factor for the presence of wheezing in infants, and for its severity. Our findings have significant implications for public health, as smoking is a modifiable behavior.

Tobacco smoking and its drug interactions with comedications involving CYP and UGT enzymes and nicotine

Tobacco smoking is a global public health threat causing several illnesses including cardiovascular disease (Myocardial infarction), cerebrovascular disease (Stroke), peripheral vascular disease (Claudication), chronic obstructive pulmonary disease, asthma, reduced female infertility, sexual dysfunction in men, different types of cancer and many other diseases. It has been estimated in 2015 that approximately 1.3 billion people smoke, around the globe. Use of medications among smokers is more common, nowadays. This review is aimed to identify the medications affected by smoking, involving Cytochrome P450 (CYP) and uridine diphosphate-glucuronosyltransferases (UGTs) enzymes and Nicotine. Polycyclic aromatic hydrocarbons (PAHs) of tobacco smoke have been associated with the induction of CYP enzymes such as CYP1A1, CYP1A2 and possibly CYP2E1 and UGT enzymes. The drugs metabolized by CYP1A1, CYP1A2, CYP2E1 and UGT enzymes might be affected by tobacco smoking and the smokers taking medications metabolized by those enzymes, may need higher doses due to decreased plasma concentrations through enhanced induction by PAHs of tobacco smoke. The prescribers and the pharmacists are required to be aware of medications affected by tobacco smoking to prevent the toxicity-associated complications during smoking cessation.

Addressing corticosteroid insensitivity in adults with asthma

Corticosteroids are the most effective treatment for asthma, but the therapeutic response varies markedly between individuals, with up to one third of patients showing evidence of insensitivity to corticosteroids. This article summarizes information on genetic, environmental and asthma-related factors as well as demographic and pharmacokinetic variables associated with corticosteroid insensitivity in asthma. Molecular mechanisms proposed to explain corticosteroid insensitivity are reviewed including alterations in glucocorticoid receptor subtype, binding and nuclear translocation, increased proinflammatory transcription factors and defective histone acetylation. Current therapies and future interventions that may restore corticosteroid sensitivity in asthma are discussed, including small molecule drugs and biological agents. In the future, biomarkers may be used in the clinic to predict corticosteroid sensitivity in patients with poorly controlled asthma.

Inhaled corticosteroids for asthma: on-demand or continuous use

Continuous inhaled corticosteroid treatment is highly effective in children and adults with mild persistent asthma, although some therapeutic benefits are not lost if treatment is delayed. Many patients do not adhere to continuous treatment with inhaled corticosteroids, but rather take them intermittently, usually at the time of increased symptoms. Based on these observations it has been proposed that for patients with mild persistent asthma inhaled corticosteroids should be used on-demand when symptoms are troublesome, rather than on a continuous basis. The article reviews the pharmacological properties of inhaled corticosteroids used in clinical trials of on-demand treatment, as well as the evidence for the efficacy and safety of on-demand compared with continuous inhaled corticosteroid treatment of mild persistent asthma in adults and children. The place of on-demand treatment with inhaled corticosteroids in the management of asthma is discussed, as well as future directions for different management strategies for this group.

A Novel Anti-Inflammatory and Pro-Resolving Role for Resolvin D1 in Acute Cigarette Smoke-Induced Lung Inflammation

Introduction

Cigarette smoke is a profound pro-inflammatory stimulus that contributes to acute lung injuries and to chronic lung disease including COPD (emphysema and chronic bronchitis). Until recently, it was assumed that resolution of inflammation was a passive process that occurred once the inflammatory stimulus was removed. It is now recognized that resolution of inflammation is a bioactive process, mediated by specialized lipid mediators, and that normal homeostasis is maintained by a balance between pro-inflammatory and pro-resolving pathways. These novel small lipid mediators, including the resolvins, protectins and maresins, are bioactive products mainly derived from dietary omega-3 and omega-6 polyunsaturated fatty acids (PUFA). We hypothesize that resolvin D1 (RvD1) has potent anti-inflammatory and pro-resolving effects in a model of cigarette smoke-induced lung inflammation.

Methods

Primary human lung fibroblasts, small airway epithelial cells and blood monocytes were treated with IL-1β or cigarette smoke extract in combination with RvD1 in vitro, production of pro-inflammatory mediators was measured. Mice were exposed to dilute mainstream cigarette smoke and treated with RvD1 either concurrently with smoke or after smoking cessation. The effects on lung inflammation and lung macrophage populations were assessed.

Results

RvD1 suppressed production of pro-inflammatory mediators by primary human cells in a dose-dependent manner. Treatment of mice with RvD1 concurrently with cigarette smoke exposure significantly reduced neutrophilic lung inflammation and production of pro-inflammatory cytokines, while upregulating the anti-inflammatory cytokine IL-10. RvD1 promoted differentiation of alternatively activated (M2) macrophages and neutrophil efferocytosis. RvD1 also accelerated the resolution of lung inflammation when given after the final smoke exposure.

Conclusions

RvD1 has potent anti-inflammatory and pro-resolving effects in cells and mice exposed to cigarette smoke. Resolvins have strong potential as a novel therapeutic approach to resolve lung injury caused by smoke and pulmonary toxicants.

Do small airway abnormalities characterize asthma phenotypes? In search of proof

The role of small airway abnormalities in asthma pathogenesis has been extensively studied and debated for several decades. However, whether or not small airway abnormalities play a relevant role in specific phenotypes of asthmatic patients and contribute to clinical presentation is largely unknown. In the present review, we evaluated available data on the role of small airways in severe asthma, with a further focus on asthma in smokers and asthma in the elderly. These phenotypes are characterized by a poor response to treatment and they can represent a model of greater small airway impairment. In severe asthmatics, small airway involvement has been shown through evidence of both distal inflammation and of increased air trapping. The few available data on asthmatics who smoke, and elderly asthmatics, similarly suggests that small airway abnormalities contribute to the pathogenesis of the disease. In this perspective, there could be a rationale for specifically assessing small airway impairment in these patients and for clinical studies evaluating whether pharmacological approaches targeting the more peripheral airways result in clinical benefits beyond conventional therapy.

1-year prospective real life monitoring of asthma control and quality of life in Italy

Objectives

The study aimed at prospectively evaluating the evolution of asthma control in Italy, to evaluate the reasons for lack of asthma control, perceived quality of life (QoL) and association with level of asthma control, the impact of pharmacological treatment, the number of exacerbations and the healthcare resource consumption.

Methods

PRISMA (PRospectIve Study on asthMA control) was an observational study performed in asthmatic patients including a cross-sectional phase and a 12-month prospective phase. Asthma control was assessed with the Asthma Control Test™ (ACT) and QoL was evaluated with EuroQoL-5D questionnaire filled in and collected during 5 clinic visits together with all the other data.

Results

The prospective phase included 1017 patients with uncontrolled (55.7%) or partly controlled asthma (44.3%). Out of the 739 patients evaluable after 12 months, 22.2% achieved full asthma control (ACT score = 25) and 58.7% reached a good control (ACT score: 20–24). The improvement in asthma control was associated with improved QoL and reduced hospital visits. The main reasons for lack of asthma control were comorbidities, continued exposure to irritants/triggers and poor adherence to therapy. The frequency of exacerbations was lower in patients with controlled asthma.

A fixed combination therapy with an inhaled corticosteroid and a long-acting β2 agonist was reported by 77.0% of patients. A better asthma control and improved QoL were achieved with extrafine beclomethasone/formoterol compared to either budesonide/formoterol or fluticasone/salmeterol.

Conclusions

An improvement in asthma control and QoL can be achieved during a 1-year monitoring in a real life setting. Extrafine beclomethasone/formoterol was associated with significant benefit in terms of asthma control and QoL compared to large-particles combinations.

ClinicalTrials.gov number NCT01110460.

Real-life prospective study on asthma control in Italy: cross-sectional phase results

OBJECTIVES

To estimate the prevalence of partly controlled and uncontrolled asthmatic patients, to evaluate quality of life and healthcare resource consumption.

METHODS

Cross-sectional phase followed by a 12-month prospective phase. Asthma Control Test and the EQ-5D were used.

RESULTS

2853 adult patients recruited in 56 Hospital Respiratory Units in Italy were evaluated: 64.4% had controlled asthma, 15.8% partly controlled asthma and 19.8% were uncontrolled. The mean (SD) EQ-5D score was 0.86 (0.17) in controlled, 0.75 (0.20) in partly controlled and 0.69 (0.23) in uncontrolled patients (p<0.001 between groups). The number of patients requiring hospitalization or emergency room visits was lower in controlled (1.8% and 1.6%, respectively) than in partly controlled (5.1% and 11.5%) and uncontrolled (6.4% and 18.6%). A combination of an inhaled corticosteroid and a long-acting beta-2 agonist was the reported therapy by 56.0% of patients, with the rate of controlled asthma and improved quality of life being higher in patients on extrafine beclomethasone/formoterol compared to budesonide/formoterol (p<0.05) and fluticasone/salmeterol (p<0.05 for quality of life).

CONCLUSIONS

Asthma control is achieved in a good proportion of Italian patients. Differences may be detected in a real-life setting in favor of extrafine beclomethasone/formoterol combination.

Urinary leukotriene E₄ levels identify children with tobacco smoke exposure at risk for asthma exacerbation

BACKGROUND

Children with asthma exposed to secondhand smoke (SHS) might be at higher risk for severe exacerbations, but biomarkers of susceptibility to SHS exposure have not been previously reported.

OBJECTIVES

We sought to assess the usefulness of urinary leukotriene E(4) (uLTE₄) levels in the prediction of increased risk of severe asthma exacerbations requiring emergency department (ED) or urgent care (UC) visits.

METHODS

Forty-four schoolchildren with moderate-to-severe asthma receiving inhaled corticosteroids were followed for 5 months with repeated measurements of uLTE₄ and monitoring of ED and UC visits. SHS exposure status was determined by using prestudy questionnaires and repeated measurements of urinary cotinine during the study.

RESULTS

Nine (45%) of 20 children with SHS exposure experienced a severe exacerbation requiring an ED or UC visit compared with 3 (12.5%) of 24 children without significant SHS exposure (relative risk, 3.6; 95% CI, 1.1-11.5; P = .02). The uLTE₄ level was a significant predictor of exacerbation risk in children exposed to SHS (area under the curve, 0.85; P = .003). Other predictors, such as nighttime symptom frequency, prebronchodilator and postbronchodilator lung function, and exhaled nitric oxide levels, were not related to exacerbations in this group. uLTE₄ levels at or greater than 106 pg/mg achieved 67% (6/9) sensitivity and 100% (11/11) specificity for predicting children with SHS exposure who required an ED or UC visit.

CONCLUSIONS

Children exposed to SHS are at increased risk for severe asthma exacerbations, despite use of inhaled corticosteroids. uLTE₄ levels identify children exposed to SHS at high risk for asthma exacerbations.

The Gap between Tobacco Treatment Guidelines, Health Service Organization, and Clinical Practice in Comprehensive Cancer Centres

Smoking cessation is necessary to reach a higher quality of life, and, for a cancer patient, it represents an important step in improving the outcome of both prognosis and therapy. Being a cancer patient addicted to nicotine may be a critical situation. We conducted a survey to monitor how many comprehensive cancer centres in Italy have an outpatient smoker clinic and which kinds of resources are available. We also inquired about inpatient services offering psychological and pharmacological support for smoking cessation, reduction, or care of acute nicotine withdrawal symptoms. What we have witnessed is a significant gap between guidelines and services. Oncologists and cancer nurses are overscheduled, with insufficient time to engage in discussion on a problem that they do not consider directly related to cancer treatment. Furthermore, smoking habits and limited training in tobacco dependence and treatment act as an important barrier and lead to the undervaluation of smokers' needs.