Association between cigarette smoking and impaired clinical symptoms in systemic sclerosis: A review

Untangling the relationship between smoking and systemic sclerosis: an analysis of the EUSTAR cohort

OBJECTIVES

To untangle the association between smoking and systemic sclerosis (SSc).

METHODS

In the European Scleroderma Trials and Research cohort, the autoantibody status was compared between ever-smokers and never-smokers. Time until disease progression was assessed using Kaplan-Meier curves. Cox models were built to investigate the influence of smoking over 15 years of follow-up. All analyses were performed for the total cohort and stratified for sex and for positivity of anti-centromere (ACA) and anti-topoisomerase antibodies (ATA).

RESULTS

Overall, 12 314 patients were included in the study. Of these, 10 393 were women (84%), 4637 were ACA-positive (38%), 3919 were ATA-positive (32%) and 4271 (35%) were ever-smokers. In men, but not in women, smoking was associated with mortality (HR 1.63, 95% CI 1.23 to 2.16, p=0.001). Ever-smoking women were at higher risk for skin progression (HR 1.10, 95% CI 1.00 to 1.22, p=0.046) and for 'any organ progression' (HR 1.07, 95% CI 1.00 to 1.13, p=0.036). In women, 34% of never-smokers were ATA-positive compared with 21% of ever-smokers (p<0.001). In the group of ever-smokers, higher exposure rates, reflected by the number of pack-years (OR 0.98, 95% CI 0.97 to 0.99, p<0.001) and by smoking duration (OR 0.96, 95% CI 0.95 to 0.97, p<0.001), were associated with lower frequency of ATA. In ACA-positive patients, the risk of mortality (HR 1.29, 95% CI 1.02 to 1.63, p=0.033), cardiac involvement (HR 1.25, 95% CI 1.03 to 1.43, p=0.001), skin progression (HR 1.21, 95% CI 1.03 to 1.42, p=0.018) and 'any organ progression' (HR 1.14, 95% CI 1.05 to 1.24, p=0.002) was increased among smokers. In ATA-positive smoking patients, mortality (HR 1.40, 95% CI 1.10 to 1.78, p=0.006), skin progression (HR 1.19, 95% CI 1.03 to 1.37, p=0.020) digital ulcers (HR 1.17, 95% CI 1.02 to 1.34, p=0.029) and 'any organ progression' (HR 1.11, 95% CI 1.00 to 1.22, p=0.048) occurred more frequently.

CONCLUSIONS

Our stratified analysis demonstrates that smoking is associated with an increased risk for mortality in male SSc patients but not in women. Strikingly, smoking is associated with lower prevalence of ATA positivity, in particular in women. In both ATA-positive and ACA-positive patients, smoking is a risk factor for mortality, skin progression and 'any organ progression'.

Comparison of pulmonary function, respiratory symptoms, functional level, and health-related quality of life in patients with systemic sclerosis according to smoking status

BACKGROUND

Patients with systemic sclerosis (SSc) are at high risk for pulmonary and vascular complications. Smoking is an important risk factor for respiratory symptoms and vascular complications of many diseases in the general population. However, studies on the role of smoking in SSc are insufficient.

AIMS

This study aimed to compare pulmonary function, respiratory symptoms, functional level, and health-related quality of life (HRQoL) in patients with SSc according to smoking status and to assess the correlation between cigarette consumption and these parameters in patients with SSc.

METHODS

Seventy-two patients with SSc (smoker group; n = 35 or nonsmoker group; n = 37) were included. The pulmonary function test was measured with a spirometer. Respiratory symptoms were questioned and the perceived severity of dyspnea and fatigue was evaluated. The functional levels were determined by questioning the patients' average daily walking distance, exercise habits, and daily sedentary time. HRQoL was assessed by Scleroderma Health Assessment Questionnaire.

RESULTS

The rate of respiratory symptoms including dyspnea, cough, and sputum were higher in the smoker group (p < .001, p = .041, and p < .001, respectively). Also, the perceived severity of dyspnea and fatigue was higher in the smoker group (p < .05). The mean daily walking distance, exercise habits, and overall HRQoL were lower (p = .004, p = .002, and p = .034, respectively) and the sedentary time and vascular complications were higher (p < .001 and p = .038, respectively) in the smoker group. However, there was no significant difference between the two groups in terms of the pulmonary function test (p > .05). There was a weak to moderate correlation between cigarette consumption and respiratory symptoms, dyspnea and fatigue severity, functional level, and HRQoL in the smoker group (0.001 ≤ p ≤ .024).

CONCLUSIONS

Smoking may increase respiratory symptoms and vascular complications and decrease the functional level and HRQoL in patients with SSc. To maintain functional independence in patients with SSc, awareness of the harms of smoking should be increased and smoking cessation should be encouraged, along with physiotherapy and rehabilitation programs including exercise and physical activity recommendations.

Increased oxidative stress response in circulating blood of systemic sclerosis patients - relation to disease characteristics and inflammatory blood biomarkers

BACKGROUND

Systemic sclerosis (SSc) is a rare connective tissue disorder of unknown etiology characterized by organ fibrosis and microcirculation dysfunction. Emerging evidence suggests that SSc is related to increased oxidative stress, which contributes to further tissue and vascular damage.

METHODS

Oxidative stress response in the peripheral blood was assessed in patients with SSc (n = 55) and well-matched controls (n = 44) using real-time monitoring of protein hydroperoxide (HP) formation by the coumarin boronic acid (CBA) assay. We also analyzed the relationship between HP generation and SSc clinics, systemic inflammation, and cellular fibronectin, an emerging biomarker of endothelial damage.

RESULTS

SSc was characterized by a significantly faster (2-fold) fluorescent product generation in the CBA assay and higher cumulative HP formation (3-fold) compared to controls (p<0.001, both). The dynamics of HP generation were not associated with the form of the disease (diffuse vs. limited SSc), current immunosuppressive therapy use, presence of abnormal nailfold capillaries, and autoantibody profile. Still, it was enhanced in patients with more severe illness and certain clinical manifestations (i.e., pulmonary hypertension, digital ulcers, and cyclophosphamide treatment) and in smokers (current or past). Higher serum CRP, blood eosinophil count, and cellular fibronectin with lower hemoglobin levels were independent determinants of increased HP formation.

CONCLUSIONS

Our data indicate a pro-oxidant imbalance in SSc, likely related to systemic inflammation and endothelial injury. However, extensive prospective studies are needed to verify whether it is also associated with clinical disease progression.

Method of Preparation of Cigarette Smoke Extract to Assess Lung Cancer-Associated Changes in Airway Epithelial Cells

Smoking tobacco is a major risk factor for the development of lung cancer, COPD, and other lung pathologies in smokers. Cigarette smoke (CS), which is comprised of several toxic components, is known to cause oxidative stress and inflammation-induced lung damage. Since airway epithelial cells act as the primary barrier, they protect the lung tissues from environmental insults, including CS. Upon exposure to these insults, airway epithelial cells act as the initial site of injury and orchestrate the pathophysiology of lung cancer. Scientists have been using cigarette smoke extract (CSE) in the preclinical model of in vitro cell culture to understand the effect of CS on the cellular, biochemical, and molecular changes in the lung epithelial cells. However, the standard procedure to prepare the CSE in the laboratory with a low-cost assembly and obtaining a reproducible quality of CSE in different batches is a challenge. Here, in this chapter, we delineate the method for the preparation of CSE using a discontinuous puff-based system which is an economical and reproducible method to prepare CSE in the laboratory. This method is suitable for studying CSE-induced molecular changes in lung diseases, including lung cancer, using in vitro models of lung adenocarcinoma cells.

Use of TIME in treating a hard-to-heal localised scleroderma wound

OBJECTIVE

Localised scleroderma is a rare disease and the wound is difficult to heal because of tissue fibrosis. We present the case of a patient with localised scleroderma treated using the TIME (tissue, infection or inflammation, moisture and edge of wound) clinical decision support tool (CDST) for wound management. This includes: assessment, bringing, control, decision and evaluation (the ABCDE approach). The patient was fully evaluated and multidisciplinary teams were involved in wound treatment. Complications of wound healing were controlled and treated, and the wound was continuously assessed until it healed.

CONCLUSION

This method of wound management provides a sound theory for the evaluation and management of hard-to-heal wounds and is worthy of clinical application.

Patients characteristics in Behçet's Syndrome and their associations with major organ involvement: a single-centre experience of 2118 cases

Objectives: To evaluate the demographic and clinical characteristics of patients with Behçet's syndrome (BS), and to define their associations with the presence of major organ involvement (MOI).Method: Medical records of 2118 patients (964 males, 1154 females) were analysed retrospectively. MOI was defined as the presence of at least one of vascular, eye, nervous, or gastrointestinal system involvement. Univariable and multivariable binary and ordinal logistic regression analyses were applied to assess the factors that were potentially associated with MOI.Results: The mean ± sd age at diagnosis was 30.5 ± 9.4 years. Genital ulcer and joint involvement were more common in females (both p < 0.001), while MOI was more frequent in males (p < 0.001). Genital ulcer (p < 0.001) and vascular involvement (p = 0.006) were more common in patients with a younger age at diagnosis, while joint involvement was more common in older patients. A total of 1097 patients (51.8%) had at least one MOI, 322 (15.2%) at least two MOIs, and 48 (2.3%) at least three MOIs. Male gender, smoking history, and absence of genital ulcer were significantly associated with MOI in multivariable binary logistic regression. Multivariable ordinal regression analyses confirmed the association between MOI and male gender and smoking, but not the protective effect of genital ulcers. In both regression analyses, we found no significant effects of age, human leucocyte antigen-B51, skin involvement, or joint involvement on MOI.Conclusion: Male gender and positive smoking history have a significant influence on the presence of MOI in patients with BS.

Association between Appendicitis and Incident Systemic Sclerosis

Objective: This nationwide study aimed to investigate the association between newly diagnosed systemic sclerosis (SSc) and previous appendicitis history. Methods: A total of 1595 patients who were newly diagnosed with SSc were recruited as the SSc cases from the 2003 to 2012 claims data of the entire population in Taiwan. The other 15,950 individuals who had never been diagnosed with SSc during 2003 and 2012 were selected as the non-SSc controls to match the SSc cases. We defined that the index date as the first date of SSc diagnosis of SSc cases and the first date of ambulatory visit for any reason of non-SSc controls. Conditional logistic regression analysis was applied for the association between appendicitis and the risk of the incident SSc, tested by estimating odds ratios (ORs) with 95% confidence intervals (CIs). Potential confounders, including the Charlson comorbidity index (CCI), a history of periodontal disease, salmonella infection, and intestinal infection, were controlled. We further designed sensitivity analyses by varying the definition of appendicitis according to the status of receiving primary appendectomy. Results: The mean age was 51 years in the case and control groups. Females accounted for 77.5%. A total of 17 (1.1%) out of 1595 SSc cases and 81 (0.5%) out of 15,950 non-SSc controls had a history of appendicitis before the index date had a history of appendicitis. A significant association between appendicitis and the risk of SSc was confirmed (OR, 2.03; 95% CI, 1.14–3.60) after adjusting potential confounders. CCI ≥ 1 (OR, 8.48; 95% CI, 7.50–9.58) and periodontal disease (OR, 1.55; 95% CI, 1.39–1.74) were also significantly associated with the risk of SSc. The association between appendicitis and SSc risk remained robust using various definitions of appendicitis. Conclusion: Our study demonstrated appendicitis was associated with the incident SSc. CCI ≥ 1 and periodontal disease also contributed to the risk of developing SSc.

Molecular "omic" signatures in systemic sclerosis

Systemic sclerosis (SSc) is a connective tissue disorder characterized by immunologic, vascular, and extracellular matrix abnormalities. Variation in the proportion and/or timing of activation in the deregulated molecular pathways that underlie SSc may explain the observed clinical heterogeneity in terms of disease phenotype and treatment response. In recent years, SSc research has generated massive amounts of "omics" level data. In this review, we discuss the body of "omics" level work in SSc and how each layer provides unique insight to our understanding of SSc. We posit that effective integration of genomic, transcriptomic, metagenomic, and epigenomic data is an important step toward precision medicine and is vital to the identification of effective therapeutic options for patients with SSc.

Toward Understanding of Environmental Risk Factors in Systemic Sclerosis [Formula: see text]

IMPORTANCE

Systemic sclerosis (SSc) is a severe, chronic, and incurable autoimmune fibrotic skin disease with significant extracutaneous involvement. Low concordance rate in twin studies and unequal geographic distribution of SSc argues for importance of environment in disease initiation and progression.

OBJECTIVE

In this manuscript we provide a summary of all investigated potential external risk factors for SSc.

DATA SOURCES

A literature search in PubMed and EMBASE database was performed for studies published until January 1, 2020 by 2 reviewers (EN and LO) independently.

FINDINGS

Occupational and/or environmental exposures to silica and organic solvents are associated with increased incidence and severity of SSc. Exposure to epoxy resins, asbestos, and particulate air pollution favors increased risk of SSc, but data are based on limited number of observational studies. There is insufficient evidence to conclude an association between SSc development and other occupational (eg, welding fumes) or personal exposures (eg, smoking, vitamin D deficiency). Association of SSc with silicone breast implants has been disproven. Infectious pathogens (eg, Helicobacter pylori and angiotropic viruses) and dysbiosis seem to play a role in SSc development and severity, but their role remains to be clarified.

CONCLUSIONS AND RELEVANCE

It may be prudent to counsel our patients with SSc (or those at risk of SSc) to avoid occupations with exposure to silica, organic solvents, asbestos and epoxy resins; restraint from smoking, using cocaine or drugs with pro-fibrotic potential. While the association between low vitamin D and SSc remains to be confirmed, we believe that SSc patients should be encouraged to maintain healthy vitamin D levels as benefits outweigh the risks.

Cigarette Smoke Extract Exposure: Effects on the Interactions between Titanium Surface and Osteoblasts

The aim of this study was to explore the changes in the characteristics of titanium surface and the osteoblast-titanium interactions under cigarette smoke extract (CSE) exposure. In this study, CSE was used to simulate the oral liquid environment around the implant under cigarette smoke exposure. Titanium samples were immersed in CSE to explore the changes in the characteristics of titanium surface. The physical properties of titanium surface were measured, including surface micromorphology, surface elemental composition, roughness, and surface hydrophilicity. MC3T3-E1 cells were cultured on the titanium surface in vitro under different concentrations of CSE exposure, and cell adhesion, cell proliferation, and osteogenic differentiation were observed. The surface micromorphology and elemental composition of titanium surface changed under CSE exposure. No obvious changes were found in the surface roughness and the hydrophilicity of titanium samples. Moreover, the results of in vitro study showed that CSE exposure downregulated the cell spreading, proliferation, and osteogenic differentiation of MC3T3-E1 cells on the titanium surface. It could be speculated that some carbon-containing compounds from CSE adsorbed on the titanium surface and the osteoblast-titanium interactions were influenced under CSE exposure. It is hoped that these results could provide valuable information for further studies on smoking-mediated inhibition of implants osseointegration.

Brief Report: Smoking in Systemic Sclerosis: A Longitudinal European Scleroderma Trials and Research Group Study

OBJECTIVE

Data on the role of tobacco exposure in systemic sclerosis (SSc; scleroderma) severity and progression are scarce. We aimed to assess the effects of smoking on the evolution of pulmonary and skin manifestations, based on the European Scleroderma Trials and Research group database.

METHODS

Adult SSc patients with data on smoking history and a 12-24-month follow-up visit were included. Associations of severity and progression of organ involvement with smoking history and the Comprehensive Smoking Index were assessed using multivariable regression analyses.

RESULTS

A total of 3,319 patients were included (mean age 57 years, 85% female); 66% were never smokers, 23% were ex-smokers, and 11% were current smokers. Current smokers had a lower percentage of antitopoisomerase autoantibodies than previous or never smokers (31% versus 40% and 45%, respectively). Never smokers had a higher baseline forced expiratory volume in 1 second/forced vital capacity (FEV₁ /FVC) ratio than previous and current smokers (P < 0.001). The FEV₁ /FVC ratio declined faster in current smokers than in never smokers (P = 0.05) or ex-smokers (P = 0.01). The baseline modified Rodnan skin thickness score (MRSS) and the MRSS decline were comparable across smoking groups. Although heavy smoking (>25 pack-years) increased the odds of digital ulcers by almost 50%, there was no robust adverse association of smoking with digital ulcer development.

CONCLUSION

The known adverse effect of smoking on bronchial airways and alveoli is also observed in SSc patients; however, robust adverse effects of smoking on the progression of SSc-specific pulmonary or cutaneous manifestations were not observed.

Association of Serum Homocysteine Level and Interstitial Lung Disease in Systemic Sclerosis: A Case-control Study

BACKGROUND

Systemic sclerosis is a disorder of connective tissue with unknown cause, affecting the skin and internal organs, characterized by fibrotic changes.

OBJECTIVE

To determine the correlation between serum homocysteine level and interstitial lung involvement in systemic sclerosis.

MATERIALS AND METHODS

In this case - control study, 59 patients who fulfilled the ACR/EULAR classification criteria for systemic sclerosis and were referred to Hafez Hospital of Shiraz, Iran, were included as the case group. Fifty nine healthy subjects were involved as the control group. Patients were divided into two groups based on interstitial lung involvement and two subtypes, diffuse and limited type. Serum homocysteine, vitamin B12, and folate levels compared between the controls, and cases groups.

RESULTS

Of 59 case and control group, 53 (%89.8) were female and the mean age did not differ in both groups (P=0.929). Thirty five (%59.3) patients had interstitial lung involvement and 38(%64.4) had diffuse cutaneous systemic sclerosis. The mean serum homocysteine level was 13.9±6.3 µmol/L in the case and 13.7±9.2 µmol/L in the control group (P=0.86). The mean serum homocysteine level did not differ between the patients with and without interstitial lung involvement (P=0.52). The patients with lung involvement was older than those without lung involvement (P=0.004). Lung disease was more common in diffuse type (P=0.014).

CONCLUSION

In our study, serum homocysteine level did not differ between the patients and healthy subjects. Also, there was no correlation between serum homocysteine level and lung involvement, but lung involvement was more common in older patients and also diffuse subtype.