Reversibility of impaired nasal mucociliary clearance in smokers following a smoking cessation programme

Prediction of postoperative complications following transanal total mesorectal excision in middle and low rectal cancer: development and internal validation of a clinical prediction model

PURPOSE

The objective of this study is to develop a nomogram for the personalized prediction of postoperative complication risks in patients with middle and low rectal cancer who are undergoing transanal total mesorectal excision (taTME). This tool aims to assist clinicians in early identification of high-risk patients and in addressing preoperative risk factors to enhance surgical safety.

METHODS

In this case-control study, 207 patients diagnosed with middle and low rectal cancer and undergoing taTME between February 2018 and November 2023 at The First Affiliated Hospital of Xiamen University were included. Independent risk factors for postoperative complications were analyzed using the Least Absolute Shrinkage and Selection Operator (LASSO) regression and multifactorial logistic regression models. A predictive nomogram was constructed using R Studio.

RESULTS

Among the 207 patients, 57 (27.5%) experienced postoperative complications. The LASSO and multifactorial logistic regression analyses identified operation time (OR = 1.010, P = 0.007), smoking history (OR = 9.693, P < 0.001), anastomotic technique (OR = 0.260, P = 0.004), and ASA score (OR = 9.077, P = 0.051) as significant predictors. These factors were integrated into the nomogram. The model's accuracy was validated through receiver operating characteristic curves, calibration curves, consistency indices, and decision curve analysis.

CONCLUSION

The developed nomogram, incorporating operation time, smoking history, anastomotic technique, and ASA score, effectively forecasts postoperative complication risks in taTME procedures. It is a valuable tool for clinicians to identify patients at heightened risk and initiate timely interventions, ultimately improving patient outcomes.

Saccharin test: Methodological validation and systematic review of the literature

OBJECTIVES

Saccharin test (ST) is a convenient method to assess the efficiency of mucociliary clearance, the primary defense mechanism of the upper airways' tract. The study objectives are to: (1) substantiate its short- (3 days) and long-term (30 days) repeatability; (2) assess its tolerability; (3) conduct a systematic literature review and to compare our results with the existing evidence.

METHODS

Twenty-nine healthy subjects were enrolled in an observational prospective study to perform an ST on three separate visits (at baseline; at follow-up visits at day 3 and at day 30). Transit times were recorded and self-reported nasal and general symptoms noted. A systematic review of the literature was conducted to compare our results with the existing literature.

RESULTS

The mean values (±SD) of ST transit time (STTT) were 7.085 (±2.19), 7.788 (±2.11), and 7.790 (±2.06) minutes at baseline, day 3, and day 30, respectively. Significant linear regression analysis was observed between day 3 and baseline (r = .193; P = .019) and day 30 and baseline (r = .182 P = .024). Significant agreement for the intrasession repeatability was observed with an ICC = .354 (P = .001). Outcomes' comparisons between baseline vs day 3 (P = .197) and baseline vs day 30 (P = .173) were not statistically significant. ST was well tolerated. Concordance with existing literature's data and high level of STTT repeatability were confirmed by the qualitative analysis.

CONCLUSION

STTT reproducibility was good both in the short- and long-term. ST tolerability was very good. Our study data are consistent with the existing literature, indicating ST as a sound methodology for detection of early respiratory health changes and for specific regulatory application in respiratory research.

Incidence and risk factors of pulmonary complications after lung cancer surgery: A systematic review and meta-analysis

Postoperative pulmonary complications (PPCs) are associated with high mortality rates after lung cancer surgery. Although some studies have discussed the different risk factors for PPCs, the relationship between these factors and their impact on PPCs remains unclear. Hence, this study aimed to systematically summarize the incidence and determine the risk factors for PPCs. We conducted a systematic search of five English and four Chinese databases from their inception to April 1, 2023. A total of 34 articles (8 cohort studies and 26 case-control studies) (n = 31696, 5833 with PPCs) were included in the analysis. The primary outcome was the incidence of PPC. The secondary outcome was the odds ratio (OR) of PPCs based on the identified risk factors calculated by RevMan 5.4. A narrative descriptive summary of the study results was presented when pooling the results or conducting a meta-analysis was not possible. The pooled incidence of PPCs was 18.4 %. This meta-analysis demonstrated that TNM staging (OR 4.29, 95 % CI 2.59-7.13), chronic obstructive pulmonary disease (COPD) (OR 2.47, 95 % CI 1.80-3.40), smoking history (OR 2.37, 95 % CI 1.33-4.21), poor compliance with respiratory rehabilitation (OR 1.64, 95 % CI 1.17-2.30), male sex (OR 1.62, 95 % CI 1.28-2.04), diabetes (OR 1.56, 95 % CI 1.07-2.27), intraoperative bleeding volume (OR 1.44, 95 % CI 1.02-2.04), Eastern Cooperative Oncology Group score (ECOG) > 1 (OR 1.37, 95 % CI 1.04-1.80), history of chemotherapy and/or radiotherapy (OR 1.32, 95 % CI 1.03-1.70), older age (OR 1.18, 95 % CI 1.11-1.24), and duration of surgery (OR 1.07, 95 % CI 1.04-1.10) were significantly associated with a higher risk of PPCs. In contrast, the peak expiratory flow rate (PEF) (OR 0.99, 95 % CI 0.98-0.99) was a protective factor. Clinicians should implement targeted and effective interventions to prevent the occurrence of PPCs.

Loss of p73 Expression Contributes to Chronic Obstructive Pulmonary Disease

Rationale: Multiciliated cell (MCC) loss and/or dysfunction is common in the small airways of patients with chronic obstructive pulmonary disease (COPD), but it is unclear if this contributes to COPD lung pathology. Objectives: To determine if loss of p73 causes a COPD-like phenotype in mice and explore whether smoking or COPD impact p73 expression. Methods: p73floxE7-E9 mice were crossed with Shh-Cre mice to generate mice lacking MCCs in the airway epithelium. The resulting p73Δairway mice were analyzed using electron microscopy, flow cytometry, morphometry, forced oscillation technique, and single-cell RNA sequencing. Furthermore, the effects of cigarette smoke on p73 transcript and protein expression were examined using in vitro and in vivo models and in studies including airway epithelium from smokers and patients with COPD. Measurements and Main Results: Loss of functional p73 in the respiratory epithelium resulted in a near-complete absence of MCCs in p73Δairway mice. In adulthood, these mice spontaneously developed neutrophilic inflammation and emphysema-like lung remodeling and had progressive loss of secretory cells. Exposure of normal airway epithelium cells to cigarette smoke rapidly and durably suppressed p73 expression in vitro and in vivo. Furthermore, tumor protein 73 mRNA expression was reduced in the airways of current smokers (n = 82) compared with former smokers (n = 69), and p73-expressing MCCs were reduced in the small airways of patients with COPD (n = 11) compared with control subjects without COPD (n = 12). Conclusions: Loss of functional p73 in murine airway epithelium results in the absence of MCCs and promotes COPD-like lung pathology. In smokers and patients with COPD, loss of p73 may contribute to MCC loss or dysfunction.

Mechanisms of airway epithelial injury and abnormal repair in asthma and COPD

The airway epithelium comprises of different cell types and acts as a physical barrier preventing pathogens, including inhaled particles and microbes, from entering the lungs. Goblet cells and submucosal glands produce mucus that traps pathogens, which are expelled from the respiratory tract by ciliated cells. Basal cells act as progenitor cells, differentiating into different epithelial cell types, to maintain homeostasis following injury. Adherens and tight junctions between cells maintain the epithelial barrier function and regulate the movement of molecules across it. In this review we discuss how abnormal epithelial structure and function, caused by chronic injury and abnormal repair, drives airway disease and specifically asthma and chronic obstructive pulmonary disease (COPD). In both diseases, inhaled allergens, pollutants and microbes disrupt junctional complexes and promote cell death, impairing the barrier function and leading to increased penetration of pathogens and a constant airway immune response. In asthma, the inflammatory response precipitates the epithelial injury and drives abnormal basal cell differentiation. This leads to reduced ciliated cells, goblet cell hyperplasia and increased epithelial mesenchymal transition, which contribute to impaired mucociliary clearance and airway remodelling. In COPD, chronic oxidative stress and inflammation trigger premature epithelial cell senescence, which contributes to loss of epithelial integrity and airway inflammation and remodelling. Increased numbers of basal cells showing deregulated differentiation, contributes to ciliary dysfunction and mucous hyperproduction in COPD airways. Defective antioxidant, antiviral and damage repair mechanisms, possibly due to genetic or epigenetic factors, may confer susceptibility to airway epithelial dysfunction in these diseases. The current evidence suggests that a constant cycle of injury and abnormal repair of the epithelium drives chronic airway inflammation and remodelling in asthma and COPD. Mechanistic understanding of injury susceptibility and damage response may lead to improved therapies for these diseases.

Predictors of Readmission After Pulmonary Resection in Patients With Lung Cancer: A Systematic Review and Meta-analysis

Objective: Postoperative readmissions are considered an indicator of healthcare quality. The purpose of this study was to assess the factors associated with readmission following pulmonary resection for lung cancer. Methods: A comprehensive search was performed in PubMed, Web of science, the Cochrane Library, and databases of CNKI and Wanfang. We collected the factors associated with readmission following pulmonary resection from the included studies, and data analysis was conducted with STATA SE12.0 software. Results: A total of 11 studies (386 012 participants) were included. The meta-analysis results showed that age (standardized mean difference [SMD] = 0.093), male sex (odds ratio [OR] = 1.260), Charlson score (SMD = 1.408), forced expiratory volume in 1 second predicted (SMD = -0.203), congestive heart failure (OR = 1.708), peripheral vascular disease (OR = 1.436), and histology (OR = 0.804) were associated with readmission (P < .05), while hypertension was not. Patients with postoperative empyema, pneumonia, air leak, and arrhythmia (all P < .05) had higher odds of hospital readmission. Conclusion: The predictive factors for readmission can help in establishing individualized discharge and follow-up plans and programs for reducing hospital readmissions after pulmonary resection in patients with lung cancer.

Epidemiology of Chronic Rhinosinusitis: Prevalence and Risk Factors

Knowledge of chronic rhinosinusitis (CRS) epidemiology may directly impact patient care: aiding patient identification and establishing accurate diagnosis as well as informing treatment decisions. The objective of this review is to summarize the current evidence on the epidemiology of CRS, with a focus on prevalence and risk factors. Although the presence of either symptoms or objective findings alone have yielded CRS prevalence estimates of over 10%, the presence of both-consistent with guideline-based diagnostic criteria for CRS-has suggested that the true prevalence of CRS is consistently less than 5%, with approximately one-third of patients with CRS having nasal polyps, in epidemiologic studies from around the world. In comparison, the prevalence of CRS endotypes-pathophysiologic subclassification of CRS most commonly as related to type 2 or non-type 2 inflammation-has been found to vary significantly by region. The epidemiology of CRS is modified and ultimately determined by risk factors: genetic/hereditary, demographic, environmental, and imparted by predictive pre-/comorbid disease. The understanding of these epidemiologic relationships may help the provider to optimally identify and understand each individual's CRS disease process, thereby improving both diagnosis and treatment.

Long-term histopathological changes of the nasal mucosa after total laryngectomy: a prospective cohort study

Background: Changes in the nasal function following total laryngectomy resulted in histopathological alterations of the nasal mucosa. We aimed to evaluate the long-term histopathological changes and the mucociliary clearance (MCC) of the nasal mucosa after total laryngectomy. Methods: We performed a histological examination of inferior turbinate biopsy, and saccharine test to assess the MCC time for patients who were candidates for total laryngectomy before the procedure, 6-12 months after surgery, and at least two years postoperatively. Results: Seventy-five patients scheduled for total laryngectomy were initially enrolled in our study. We excluded patients who received postoperative radiotherapy or were lost during the follow-up period. Eventually, 63 and 54 patients were available for assessment 6-12 months after surgery and at least two years postoperatively, respectively. Except for ciliary and goblet cell destruction, which were significantly reduced 6-12 months postoperatively, there were no statistically significant differences in the histopathological findings of the nasal mucosa before surgery and 6-12 months postoperatively. After two years, the histopathological alterations of the nasal mucosa were statistically more evident than those before surgery and 6-12 months postoperatively; the most common histopathological findings were mononuclear cell infiltration and stromal fibrosis. The mean MCC time preoperatively was 12.56 minutes that statistically significantly decreased to 11.81 minutes 6-12 months after surgery; then, it significantly increased to 20.98 minutes at least two years postoperatively. Conclusions: After total laryngectomy, the nasal mucosa showed histopathological alterations and early enhancement of the MCC, which was later impaired due to nasal mucosal atrophy and the saprophytic infection.

Impact of exclusive e-cigarettes and heated tobacco products use on muco-ciliary clearance

Background:

Tobacco smoking impairs mucociliary clearance (MCC) efficiency as shown by prolonged saccharin test transit time (STTT). Avoiding exposure to tobacco smoke from combustible cigarettes may restore MCC function and former smokers have been shown to exhibit similar STTT as never smokers. The impact on STTT of switching from smoking to combustion-free tobacco products such as e-cigarettes (ECs) and heated tobacco products (HTPs) is not known.

Methods:

We report STTT of exclusive EC and HTP users. Test results were compared with those obtained in current, former, and never smokers.

Results:

STTT were obtained from 39 current, 40 former, 40 never smokers, and from 20 EC and 20 HTP users. Comparison of STTT values showed significant difference among the five study groups (p < 0.00001) with current smokers having a median [interquartile range (IQR)] STTT of 13.15 min, which was significantly longer compared with that of all other study groups. In particular, compared with former (7.26 min) and never smokers (7.24 min), exclusive EC users and exclusive HTP users had similar STTT at 7.00 and 8.00 min, respectively.

Conclusion:

Former smokers who have switched to exclusive regular use of combustion-free nicotine delivery systems (i.e., ECs and HTPs) exhibit similar saccharin transit time as never and former smokers. This suggests that combustion-free nicotine delivery technologies are unlikely to have detrimental effects on MCC function.

Short and Long Term Repeatability of Saccharin Transit Time in Current, Former, and Never Smokers

Smoking progressively damages the efficiency of mucociliary clearance (MCC) defense mechanisms, thus contributing to increased susceptibility to respiratory infections. Prolonged mucociliary clearance transit time (MCCTT) caused by chronic smoking has been investigated by saccharin test, but little data is available about its short- and long-term reproducibility. Moreover, it is not known if MCC impairment can be reversed when stopping smoking. Objective of the study is to investigate and compare short (3 days) and long term (30 days) repeatability of baseline saccharin transit time (STT) among current, former, and never smokers. STT results were analyzed in 39 current, 40 former, and 40 never smokers. Significant (p < 0.0001) short-term and long-term repeatability of STT were observed in current (R squared = 0.398 and 0.672, for short- and long-term, respectively) and former smokers (R squared = 0.714 and 0.595, for short- and long-term, respectively). Significant differences in MCCTT were observed among the three study groups (p < 0.0001); the median (IQR) MCCTT being 13.15 (10.24–17.25), 7.26 (6.18–9.17), and 7.24 (5.73–8.73) minutes for current, former and never smokers, respectively. Comparison between current smokers and former smokers was significantly different (p < 0.0001). There was no significant difference between former and never smokers. The Saccharin test was well tolerated by all participants. We have shown for the first time high level repeatability in both current and former smokers. Moreover, MCC impairment can be completely reversed, former smokers exhibiting similar STT as never smokers. Measurement of STT is a sensitive biomarker of physiological effect for the detection of early respiratory health changes and may be useful for clinical research.

Influência de uma sessão de exercício aeróbico submáximo e máximo sobre o transporte mucociliar e função autonômica em tabagistas

RESUMO O objetivo do estudo foi avaliar e correlacionar o comportamento da depuração mucociliar e do sistema nervoso autônomo de fumantes após sessões de exercício aeróbico submáximo e máximo. Foram avaliados 25 fumantes e 15 não fumantes, entre 30 e 50 anos. Ambos os grupos foram submetidos ao teste do tempo de trânsito de sacarina (TTS) e variabilidade da frequência cardíaca (VFC) antes e após uma sessão de exercício submáximo (teste de caminhada de seis minutos) e máximo (teste de exercício cardiopulmonar). Teste t pareado ou Wilcoxon foi utilizado para análise intragrupos e o teste t não pareado ou Mann-Whitney para a análise intergrupos. A correlação foi realizada utilizando os coeficientes de Pearson ou Spearman (p <0,05). Houve redução significativa do TTS após exercícios submáximo e máximo em ambos os grupos. Após o exercício submáximo, ambos grupos apresentaram redução significativa do intervalo RR e aumento da FC em comparação ao repouso, no grupo de não fumantes houve reduções significativas nos índices RMSSD, HFms² e SD1. Após o exercício máximo, ambos grupos apresentaram reduções significativas no SDNN, RMSSD, intervalo RR, LF e HF, em ms² e un, SD1 e SD2, além do aumento da FC, LFun e da razão LF/HF. Houve correlação positiva entre TTS e LFms² (r = 0,520, p = 0,008) após o exercício máximo para o grupo de fumantes. Conclui-se que independentemente da intensidade do exercício aeróbio, houve um aumento na depuração mucociliar em fumantes, mas essa alteração parece ser influenciada pelo sistema nervoso autônomo apenas frente o exercício máximo.

Nasal Mucociliary Clearance in Smokers: A Systematic Review

Introduction  Smoking is one of the most important causes of mortality and morbidity in the world, as it is related to the risk factor and etiology of respiratory-tract diseases. Long-term smoking causes both structural and functional damage in the respiratory airways, leading to changes in nasal mucociliary clearance (NMC). Objectives  The aim of the present study was to look systematically into the current literature and carefully collect and analyze results to explore NMC in smokers. Data Synthesis  Two independent reviewers conducted a literature search on some Electronic database: Pubmed, Medline, Ebsco, Springer Link, Science Direct, Scopus, and Proquest searching for articles fulfilling the inclusion and exclusion criteria. The lead author independently assessed the risk of bias of each of the included studies and discussed their assessments with the other two authors to achieve consensus. Of the 1,654 articles identified in the database search, 16 met the criteria for this review. Most of the articles (15 out of 16) showed the impairment of NMC in smokers. Conclusion  The present systematic review suggests that there is an impairment of NMC in smokers. The impairment is not only observed in cigarette smoking, but also in passive smoking, bidi smoking, electronic smoking, and hookah smoking. The impairment of NMC in chronic exposure to smoking is caused by the ciliotoxic effect, hypersecretion and viscoelastic change of mucous, airway surface liquid depletion, increased oxidative stress, and deteriorations in the inflammatory and immune systems.

Particularities and Clinical Applicability of Saccharin Transit Time Test

Introduction  The importance of mucociliary clearance (MCC) for the respiratory system homeostasis is clear. Therefore, evaluating this defense mechanism is fundamental in scientific research and in the clinical practice of pulmonology and of associated areas. However, MCC evaluation has not been so usual due to the complexity of methods that use radiolabeled particles. Nevertheless, as an interesting alternative, there is the saccharin transit time (STT) test. This method is reproducible, simple to perform, noninvasive, does not demand high costs, and has been widely used in studies of nasal MCC. Although the STT test is widely used, there is still lack of a detailed description of its realization. Objective  The present literature review aims to provide basic information related to the STT test and to present the findings of the previous studies that used this method, discussing variations in its execution, possible influences on the obtained results and limitations of the method, as well as to relate our experience with the use of STT in researches. Data Synthesis  There are several factors that can alter the results obtained from STT tests, which would raise difficulties with proper interpretation and with the discussion of the results among different studies. Conclusions  Saccharin transit time is a widely used method for the evaluation of nasal MCC, and therefore, the standardization related to the previous and concurrent to test orientations, and also its execution, become essential to improve its accuracy, and allow comparisons among different studies.

Mucociliary transport as a link between chronic rhinosinusitis and trace element dysbalance

Chronis rhinosinusitis is considered as a widespread public health issue with a prevalence of 10%. The disease significantly reduces quality of life and increases the risk of cardiovascular diseases as well as certain forms of cancer. Alteration of mucociliary clearance frequently observed in the patients and plays a significant role in disease pathogenesis. Certain studies have demonstrated that patients with chronic rhinosinusitis are characterized by significant reduction of essential trace elements and toxic metal overload. However, the particular mechanisms of the role of trace element dysbalance in chronic rhinosinusitis are unclear. We hypothesize that exposure to toxic trace elements (arsenic, nickel, cadmium) damages ciliary mucosal epithelium thus affecting mucociliary transport. In turn, altered mucociliary transport results in reduced removal of the inhaled metal-containing particles from nasal mucosa leading to their absorption and further aggravation of toxicity. Essential trace elements (zinc, selenium) play a significant role in regulation of mucociliary transport and immunity, thus their deficiency (either dietary or due to antagonism with toxic metals) may be associated with impaired functions and increased toxic metal toxicity. Therefore, a vicious circle involving metal accumulation and toxicity, essential element deficiency, impairment of mucociliary transport and metal particle removal, resulting in further accumulation of metals and aggravation of toxic effects is formed. The present hypothesis is supported by the findings on the impact of trace elements especially zinc and arsenic on mucociliary clearance, the role of mucociliary transport in heavy metal particles elimination from the airways, trace element dysbalance in chronic rhinosinusitis, as well as toxic and essential metal antagonism. The data from hypothesis testing and its verification may be used for development of therapeutic approach for management of chronic rhinosinusitis. Particularly, the use of essential elements (zinc, selenium) may reduce toxic metal toxicity thus destroying the vicious circle of heavy metal exposure, toxicity, alteration of mucociliary clearance, and aggravation of chronic rhinosinusitis. Essential element supplementation may be considered as a tool for management of chronic refractory rhinosinusitis. In addition, analysis of essential and toxic trace element status may provide an additional diagnostic approach to risk assessment of chronic rhinosinusitis in highly polluted environments.

Resistance exercise training improves mucociliary clearance in subjects with COPD: A randomized clinical trial

INTRODUCTION

Elastic tubing was recently investigated as an alternative to the conventional resistance training (RT) in chronic obstructive pulmonary disease (COPD). The effects of RT on the mucociliary system have not yet been reported in the literature.

OBJECTIVE

The aim of this study was to evaluate the effects of two RT programs on mucociliary clearance in subjects with COPD.

METHODS

Twentyeight subjects with COPD were randomly allocated by strata, according to individual strength of lower limbs, to defined groups: conventional resistance training (GCT) or resistance training using elastic tubing (GET). Nineteen subjects (GET: n=9; GCT: n=10) completed the study and were included in the analysis. The measurement of vital signs (blood pressure, heart rate and respiratory rate), lung function (spirometry) and the primary outcome mucociliary clearance analysis (saccharin transit time test (STT)) were performed before and after the 12 weeks of RT.

RESULTS

In relation to the mucociliary transportability analysis, no differences were observed between the baseline evaluations of the training groups (p=0.05). There was a significant reduction in the STT values in both training groups, GET (10.64±5.06 to 6.01±4.91) and GCT (12.07±5.10 to 7.36±2.54) with p=0.03. However, no differences between groups were observed on the magnitude of SST changes after interventions (GET: -43.51%; GCT: -38.94%; p=0.97).

CONCLUSION

The present study demonstrated that both RT with elastic tubing and conventional training with weights promoted similar gains in the mucociliary transportability of subjects with COPD.

Smoking and timing of cessation on postoperative pulmonary complications after curative-intent lung cancer surgery

BACKGROUND

Smoking is a risk factor for postoperative pulmonary complications (PPC) following non-small cell lung cancer (NSCLC) surgery. The optimal timing for preoperative smoking cessation has not been identified. Our study aimed to observe the impact of preoperative smoking cessation on PPC incidence and other postoperative outcomes including long-term survival.

METHODS

A prospective study included consecutive patients following resection for NSCLC in a regional thoracic centre over a 4-year period (2010-2014). Patients were stratified according to self-reported preoperative smoking status. The primary endpoint was PPC incidence, which was assessed from postoperative day one onwards using the Melbourne Group Scale. Secondary endpoints included short-term outcomes (hospital length of stay [LOS], intensive therapy unit [ITU] admission, 30-day hospital readmission rate) and long-term survival.

RESULTS

Four hundred and sixty-two patients included 111 (24%) current smokers, 55 (12%) ex-smokers <6 weeks, 245 (53%) ex-smokers ≥6 weeks and 51 (11%) never smokers. PPC occurred in 60 (13%) patients in total. Compared to never smokers, current smokers had a higher frequency of PPC (22% vs. 2%, p = 0.004), higher frequency of ITU admission (14% vs. 0%; p = 0.001) and a longer median (IQR) hospital LOS (6 [5] vs. 5 [2]; p = 0.001). In the ex-smokers there was a trend for a lower frequency of PPC (<6 weeks, 10.9% vs. ≥6 weeks, 11.8%) and ITU admission (<6 weeks, 5.5% vs. ≥6 weeks, 4.5%), but there was no difference between the <6 weeks or ≥6 weeks ex-smoking groups prior to surgery. There was no significant difference in long-term survival found between the groups of differing smoking status (median follow-up 29.8 months, 95%CI 28.4-31.1).

CONCLUSION

Current smokers have higher postoperative morbidity; this risk reduces following smoking cessation but 6 weeks does not appear to identify a time-point where differences in outcomes are noted.

The effects of smoking and smoking cessation on nasal mucociliary clearance, mucus properties and inflammation

OBJECTIVE

The aim of the present study was to assess nasal mucociliary clearance, mucus properties and inflammation in smokers and subjects enrolled in a Smoking Cessation Program (referred to as quitters).

METHOD

A total of 33 subjects with a median (IQR) smoking history of 34 (20-58) pack years were examined for nasal mucociliary clearance using a saccharine transit test, mucus properties using contact angle and sneeze clearability tests, and quantification of inflammatory and epithelial cells, IL-6 and IL-8 concentrations in nasal lavage fluid. Twenty quitters (mean age: 51 years, 9 male) were assessed at baseline, 1 month, 3 months and 12 months after smoking cessation, and 13 smokers (mean age: 52 years, 6 male) were assessed at baseline and after 12 months. Clinicaltrials.gov: NCT02136550.

RESULTS

Smokers and quitters showed similar demographic characteristics and morbidities. At baseline, all subjects showed impaired nasal mucociliary clearance (mean 17.6 min), although 63% and 85% of the quitters demonstrated significant nasal mucociliary clearance improvement at 1 month and 12 months, respectively. At 12 months, quitters also showed mucus sneeze clearability improvement (∼26%), an increased number of macrophages (2-fold) and no changes in mucus contact angle or cytokine concentrations.

CONCLUSION

This study showed that smoking cessation induced early improvements in nasal mucociliary clearance independent of mucus properties and inflammation. Changes in mucus properties were observed after only 12 months of smoking cessation.

Effects of 12 weeks of aerobic training on autonomic modulation, mucociliary clearance, and aerobic parameters in patients with COPD

Introduction

Patients with chronic obstructive pulmonary disease (COPD) exhibit aerobic function, autonomic nervous system, and mucociliary clearance alterations. These parameters can be attenuated by aerobic training, which can be applied with continuous or interval efforts. However, the possible effects of aerobic training, using progressively both continuous and interval sessions (ie, linear periodization), require further investigation.

Aim

To analyze the effects of 12-week aerobic training using continuous and interval sessions on autonomic modulation, mucociliary clearance, and aerobic function in patients with COPD.

Methods

Sixteen patients with COPD were divided into an aerobic (continuous and interval) training group (AT) (n=10) and a control group (CG) (n=6). An incremental test (initial speed of 2.0 km·h⁻¹, constant slope of 3%, and increments of 0.5 km·h⁻¹ every 2 minutes) was performed. The training group underwent training for 4 weeks at 60% of the peak velocity reached in the incremental test (vVO_2peak) (50 minutes of continuous effort), followed by 4 weeks of sessions at 75% of vVO_2peak (30 minutes of continuous effort), and 4 weeks of interval training (5×3-minute effort at vVO_2peak, separated by 1 minute of passive recovery). Intensities were adjusted through an incremental test performed at the end of each period.

Results

The AT presented an increase in the high frequency index (ms²) (P=0.04), peak oxygen uptake (VO_2peak) (P=0.01), vVO_2peak (P=0.04), and anaerobic threshold (P=0.02). No significant changes were observed in the CG (P>0.21) group. Neither of the groups presented changes in mucociliary clearance after 12 weeks (AT: P=0.94 and CG: P=0.69).

Conclusion

Twelve weeks of aerobic training (continuous and interval sessions) positively influenced the autonomic modulation and aerobic parameters in patients with COPD. However, mucociliary clearance was not affected by aerobic training.

Cilia dysfunction in lung disease

A characteristic feature of the human airway epithelium is the presence of ciliated cells bearing motile cilia, specialized cell surface projections containing axonemes composed of microtubules and dynein arms, which provide ATP-driven motility. In the airways, cilia function in concert with airway mucus to mediate the critical function of mucociliary clearance, cleansing the airways of inhaled particles and pathogens. The prototypical disorder of respiratory cilia is primary ciliary dyskinesia, an inherited disorder that leads to impaired mucociliary clearance, to repeated chest infections, and to the progressive destruction of lung architecture. Numerous acquired lung diseases are also marked by abnormalities in both cilia structure and function. In this review we summarize current knowledge regarding airway ciliated cells and cilia, how they function to maintain a healthy epithelium, and how disorders of cilia structure and function contribute to inherited and acquired lung disease.

Young "healthy" smokers have functional and inflammatory changes in the nasal and the lower airways

BACKGROUND

Smoking is responsible for most COPD. Although people with COPD often have concomitant nasal disease, there are few studies that report physiologic or inflammatory changes in the upper airways in young asymptomatic smokers. We investigated physiologic and inflammatory changes in the nasal and lower airways of young smokers and if these changes were related to smoking history.

METHODS

Seventy-two subjects aged between 18 and 35 years (32 healthy nonsmokers and 40 young smokers) participated in this study. We measured nasal mucociliary clearance (MCC), nasal mucus surface contact angle, cell counts, myeloperoxidase and cytokine concentrations in nasal lavage fluid, exhaled breath condensate (EBC) pH, and lung function.

RESULTS

Smokers had faster MCC, an increased number of cells (macrophages, ciliated cells, and goblet cells), increased lavage myeloperoxidase concentration, and decreased EBC pH compared with nonsmokers. There was a significant inverse relationship between pack-year smoking history and EBC pH. There were no differences in lung function or mucus surface properties comparing smokers to nonsmokers.

CONCLUSIONS

Young adult smokers have functional and inflammatory changes in the nasal and lower airways and these correlate with smoking history. However, in these young smokers, smoking history was not associated with pulmonary function decline, probably because it is unlikely that spirometry detects early physiologic changes in the airways.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT01877291; URL: www.clinicaltrials.gov.

How does parental smoking affect nasal mucociliary clearance in children?

Correlation between passive smoking and nasal mucociliary clearance (MCC) in pediatric population has not been reported before. Therefore, in this study, we aimed to investigate the relationship between environmental tobacco smoke and nasal MCC in children whose parents smoke in or outside the house. Three groups of subjects were evaluated: control group (group 1) with 18 children who were not exposed to environmental smoke, 15 passive smokers living with at least one adult household member smoking outside the house (group 2), 17 passive smokers living with at least one adult household member smoking inside the house (group 3). Parents of children were asked to answer our questions regarding their smoking history, and nasal MCC time was assessed for all individuals of the 3 groups. The mean MCC value in control group, group 2 and group 3 were 7.33 ± 2.91, 10.00 ± 4.78 and 12.41 ± 3.44, respectively. Differences between the mean nasal MCC values of the groups were statistically significant (p < 0.01). The comparison of MCC values between control group and group 2 did not reveal significant difference, but since p value was very close to significance level, in larger series it could be significant. (p = 0.067). Also, when we compared the MCC values between group 2 and group 3, there was no significant difference (p = 0.173). But, the difference between MCC values of control group and group 3 was statistically significant (p < 0.001). Parental smoking both inside or outside the house seemed to increase nasal mucociliary clearance time when they are compared with healthy controls. Further studies with larger study groups also measuring direct quantitative doses of smoking are needed to verify this important issue.

Nasal and systemic inflammatory profile after short term smoking cessation

INTRODUCTION

Smoking cessation promotes health benefits and, despite cigarette smoking be an important pro inflammatory stimulus, there are few studies concerning the nasal and systemic inflammation; as well as the mucociliary clearance behavior in smokers after short period of smoking cessation.

AIM

To evaluate the nasal and systemic inflammatory markers and mucociliary clearance behavior after 30 days of cigarette smoking abstinence.

METHODS

Twenty-five smokers were included and divided into two groups: abstinent smokers (n = 14) and current smokers (n = 11). Tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, IL-8 and IL-10 were measured on nasal lavage and blood serum samples by ELISA at baseline and after 30 days. The mucociliary clearance, exhaled carbon monoxide (exCO) and carboxyhemoglobin (HbCO) were also measured at the same moments.

RESULTS

There was a decrease of TNF-α level only in blood serum at 30 days of abstinence compared to current smokers. The mucociliary clearance improved and there was a reduction in exCO and HbCO (p < 0.05 for all) after 30 days of smoking cessation.

CONCLUSION

The short term smoking abstinence decreased systemic inflammation and improved nasal mucociliary clearance, despite not having changed the nasal inflammation.

Effects of cigarette smoking intensity on the mucociliary clearance of active smokers

BACKGROUND

Smoking impairs mucociliary clearance and increases respiratory infection frequency and severity in subjects with and without smoking-related chronic lung diseases.

OBJECTIVE

This study evaluated the effects of smoking intensity on mucociliary clearance in active smokers.

METHODS

Seventy-five active smokers were grouped into light (1-10 cigarettes/day; n = 14), moderate (11-20 cigarettes/day; n = 34) and heavy smokers (≥21 cigarettes/day; n = 27) before starting a smoking cessation programme. Smoking behaviour, nicotine dependence, pulmonary function, carbon monoxide in exhaled air (exCO), carboxyhaemoglobin (COHb) and mucociliary clearance measured by the saccharin transit time (STT) test were all evaluated. An age-matched non-smoker group (n = 24) was assessed using the same tests.

RESULTS

Moderate (49 ± 7 years) and heavy smokers (46 ± 8 years) had higher STT (p = 0.0001), exCO (p < 0.0001) and COHb (p < 0.0001) levels compared with light smokers (51 ± 15 years) and non-smokers (50 ± 11 years). A positive correlation was observed between STT and exCO (r = 0.4; p < 0.0001), STT and cigarettes/day (r = 0.3, p = 0.02) and exCO and cigarettes/day (r = 0.3, p < 0.01).

CONCLUSION

Smoking impairs mucociliary clearance and is associated with cigarette smoking intensity.