Smoking as a risk factor for chronic airways disease

Effects of Cigarette Smoke on TSPO-related Mitochondrial Processes

The 18 kDa translocator protein (TSPO) is an initiator of the mitochondrial apoptosis cascade. Cigarette smoke (CS) exposure provokes alterations in TSPO expression as well as upregulation of its related functions such as mitochondrial membrane potential (ΔψM) and reactive oxygen species generation, which are associated with cell death. In the current study, H1299 lung cancer cell line exposed to CS for various time periods (30 mins, 60 mins and 120 mins) and TSPO expression and cell death processes were studied. CS exposure for 30 mins resulted in a non-significant increase in TSPO expression by 24% (p > 0.05 vs. control). CS exposure for 60 mins and 120 mins resulted in a significant increase by 43% (p < 0.05 vs. control) and by 47% (p < 0.01 vs. control), respectively. Furthermore, TSPO-related mitochondrial functions were upregulated at the 120 mins time point following CS exposure. TSPO expression is upregulated by CS, suggesting that TSPO plays a role in cell death processes induced by CS exposure. Alterations in TSPO-related cell death processes suggest that TSPO may be involved in the tissue damage caused by CS.

Official Positions for FRAX® clinical regarding smoking from Joint Official Positions Development Conference of the International Society for Clinical Densitometry and International Osteoporosis Foundation on FRAX®

The worldwide prevalence of smoking has been estimated at about 50% in men, and 10% in women, with larger variations among different populations studied. Smoking has been shown to affect many organ systems resulting in severe morbidity and increased mortality. In addition, smoking has been identified as a predictor of ten-year fracture risk in men and women, largely independent of an individual's bone mineral density. This finding has eventually lead to incorporation of this risk factor into FRAX®, an algorithm that has been developed to calculate an individual's ten-year fracture risk. However, only little, or conflicting data is available on a possible association between smoking dose, duration, length of time after cessation, type of tobacco and fracture risk, limiting this risk factor's applicability in the context of FRAX®.

Cigarette smoking and self-assessed upper airway health

Habitual smoking represents a chronic insult to the airway. However, the effects of smoking on upper airway health remains poorly described. Our objective was to examine the relationship between cigarette smoking and self-assessed upper airway health and evaluate dose-response relationships between exposure and complaints in a sample of 2,523 patients. Eligible subjects were adults referred to ENT specialist for evaluation of chronic nasal or sleep-related complaints. Thirteen specific symptoms and conditions, mainly related to the upper airway, were graded based on visual analog scales (VAS). Smokers, representing 33% of the sample, were more likely to report severe upper airway complaints compared to non-smokers (odds ratio 1.31-2.08) and exhibited significantly higher visual analog scale scores than non-smokers for 9 out of 13 outcome variables (p < 0.001-0.007). Further, significant associations were found between cigarette consumption and severity of complaints (p < 0.001-0.01), heavy smokers generally being more likely to exhibit high VAS scores than light smokers. In several cases smoking status and self-reported asthma/allergy had similar impact on subjective outcomes. Cigarette smoking was clearly associated with impaired upper airway health and seemed to be an important determinant in subjects seeking medical attention due to chronic nasal or sleep-related complaints. Both threshold and dose-response like relationships were evident between cigarette consumption and the outcome measures.

Systemic effects of smoking

Smoking is one of the major lifestyle factors influencing the health of human beings. Life-long cigarette smokers have a higher prevalence of common diseases such as atherosclerosis and COPD with significant systemic impact. The present review evaluates current knowledge concerning possible pathways through which cigarette smoking can affect human health, with special focus on extrapulmonary effects. Long-term smoke exposure can result in systemic oxidants-antioxidants imbalance as reflected by increased products of lipid peroxidation and depleted levels of antioxidants like vitamins A and C in plasma of smokers. A low-grade systemic inflammatory response is evident in smokers as confirmed by numerous population-based studies: elevated levels of C-reactive protein (CRP), fibrinogen, and interleukin-6, as well as increased counts of WBC have been reported. Furthermore, rheologic, coagulation and endothelial function markers like hematocrit, blood and/or plasma viscosity, fibrin d-dimer, circulating adhesion molecules (intracellular adhesion molecule-1, selectins), tissue plasminogen activator antigen, and plasminogen activator inhibitor type I are altered in chronic cigarette smokers. Although most of smoking-induced changes are reversible after quitting, some inflammatory mediators like CRP are still significantly raised in ex-smokers up to 10 to 20 years after quitting, suggesting ongoing low-grade inflammatory response persisting in former smokers. New longitudinal epidemiologic and genetic studies are required to evaluate the role of smoking itself and possible gene/environment interplay in initiation and development of smoking-induced common diseases affecting humans.

Obstructive pulmonary disease. The clinician's perspective

This article reviews the differential diagnosis of obstructive lung disease, including lesions that may mimic chronic obstructive pulmonary disease, as well as the tools on which the clinician relies for making a proper diagnosis. The clinician's view of the radiologist's role is briefly discussed, but the details of specific radiologic techniques are discussed elsewhere in this issue.

COPD in the elderly. A reversible cause of functional impairment

OBJECTIVES

To determine the frequency of referral of patients age 69 years and older to the pulmonary function laboratory at a tertiary-care hospital for airflow limitation studies; to determine the point prevalence of a significant reversible component in patients with COPD as an age-related function; and to determine the proportion of patients who were prescribed bronchodilators following a pulmonary function test (PFT) demonstrating significant reversibility.

DESIGN

A retrospective review of pulmonary function tests of patients 69 years and older within calendar year 1990 was performed. Chart review of those showing significant reversibility to bronchodilators during a PFT was performed to determine level of follow-up.

SETTING

Referral-based pulmonary division in a tertiary-care hospital.

PATIENTS

Men and women 69 years and older who had interpretable PFTs at Northwestern Memorial Hospital (NMH) during the calendar year 1990 (n = 405). Patients whose PFTs were uninterpretable due to poor effort (n = 10) were excluded from the study.

INTERVENTIONS

No specific interventions were performed as a part of the study. Referring physicians may have requested a PFT with postbronchodilator (albuterol by nebulizer) testing and may have subsequently prescribed bronchodilators for their patients.

MEASUREMENTS

We studied the effect of age, gender, smoking history, and degree of airflow obstruction on changes in spirometry values and reversibility status after bronchodilator (if applicable) as determined by a PFT.

MAIN RESULTS

Of the 405 consecutive elderly patients studied, 193 (47.7%) received bronchodilators and 60 (31.1%) of these patients had significant improvement as judged by the criteria listed in the Methods section. The improvement occurred equally across all age groups (p > 0.05) and the percent responding to bronchodilators increased as the degree of obstruction increased (p < 0.001). Those who had never smoked were twice as likely to respond than were current or former smokers; men were more likely to respond than women. Most patients (84%) who responded were subsequently prescribed bronchodilators.

CONCLUSIONS

Responses to inhaled bronchodilators occur at all ages. Older patients showed greater reversibility as the degree of obstruction increased, while a smoking history reduced the likelihood of a bronchodilator response. COPD in the elderly may differ from the traditional form of the disease.