Risk factors for osteoporosis in male patients with chronic obstructive pulmonary disease in Taiwan

Arginine, Transsulfuration, and Folic Acid Pathway Metabolomics in Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

There is an increasing interest in biomarkers of nitric oxide dysregulation and oxidative stress to guide management and identify new therapeutic targets in patients with chronic obstructive pulmonary disease (COPD). We conducted a systematic review and meta-analysis of the association between circulating metabolites within the arginine (arginine, citrulline, ornithine, asymmetric, ADMA, and symmetric, SDMA dimethylarginine), transsulfuration (methionine, homocysteine, and cysteine) and folic acid (folic acid, vitamin B6, and vitamin B12) metabolic pathways and COPD. We searched electronic databases from inception to 30 June 2023 and assessed the risk of bias and the certainty of evidence. In 21 eligible studies, compared to healthy controls, patients with stable COPD had significantly lower methionine (standardized mean difference, SMD = -0.50, 95% CI -0.95 to -0.05, p = 0.029) and folic acid (SMD = -0.37, 95% CI -0.65 to -0.09, p = 0.009), and higher homocysteine (SMD = 0.78, 95% CI 0.48 to 1.07, p < 0.001) and cysteine concentrations (SMD = 0.34, 95% CI 0.02 to 0.66, p = 0.038). Additionally, COPD was associated with significantly higher ADMA (SMD = 1.27, 95% CI 0.08 to 2.46, p = 0.037), SDMA (SMD = 3.94, 95% CI 0.79 to 7.08, p = 0.014), and ornithine concentrations (SMD = 0.67, 95% CI 0.13 to 1.22, p = 0.015). In subgroup analysis, the SMD of homocysteine was significantly associated with the biological matrix assessed and the forced expiratory volume in the first second to forced vital capacity ratio, but not with age, study location, or analytical method used. Our study suggests that the presence of significant alterations in metabolites within the arginine, transsulfuration, and folic acid pathways can be useful for assessing nitric oxide dysregulation and oxidative stress and identifying novel treatment targets in COPD. (PROSPERO registration number: CRD42023448036.).

FeNO, systemic inflammation and other risk factors for osteoporosis in COPD

Introduction: The bone is one of the tissues that is adversely affected as a result of inflammation in COPD. The aim of this study is to examine the relationship between airway inflammation, systemic inflammation and osteoporosis in COPD. Material and methods: A cross-sectional study was performed, including 50 patients with stable COPD. FeNO as a marker of airway inflammation; hs-CRP, WBC and fibrinogen as systemic inflammation markers; arterial blood gas, BMI and FEV1 were measured. To identify osteoporosis, DEXA was performed. Results: The prevalence of osteoporosis was 26%. Osteoporosis was associated with WBC and hs-CRP (OR: 1.80, 95% CI, 1.26-2.57 and OR: 2.32, 95% CI, 1.28-4.20, respectively). It was observed that the risk increased as FEV1 and BMI decreased (OR: 0.94, 95% CI, 0.89-0.98 and OR: 0.75, 95% CI, 0.61-0.91, respectively). There was no relationship between osteoporosis and FeNO and fibrinogen (OR: 1.05, 95% CI, 0.99-1.12 and OR: 1.04, 95% CI 0.98-1.09, respectively). Arterial blood gases (PaO2 and PaCO2) were not effective on osteoporosis (OR: 1.01, 95% CI, 0.95-1.05 and OR: 1.04, 95% CI, 0.90-1.19, respectively). The cut-off values of hs-CRP and WBC for osteoporosis risk were 15.9 mg/L and 11.6 x 109/L, respectively. Conclusions: Osteoporosis was associated with low BMI, airway stenosis and high levels of hs-CRP and WBC.

Osteoporosis in COPD patients: Risk factors and pulmonary rehabilitation

Objectives

To present a review on the pathogenesis, risk factor and treatment of chronic obstructive pulmonary disease complicated with osteoporosis and provide new ideas for the diagnosis and treatment.

Data source

A systematic search is carried out using keywords as chronic obstructive pulmonary disease, osteoporosis, risk factors, and pulmonary rehabilitation.

Results

Patients with chronic obstructive pulmonary disease have a high prevalence of osteoporosis and a high risk of fracture. The mechanisms of osteoporosis in COPD patients are associated with general risk factors, such as smoking, reduced physical activity, low weight, and disease‐specific risk factors, such as systemic inflammatory, Vitamin D deficiency, use of glucocorticoid, anemia, hypoxemia, and hypercapnia. The treatment of osteoporosis in COPD emphasizes comprehensive intervention, which mainly include basic treatment and anti‐osteoporosis drugs. Noticeably, pulmonary rehabilitation program is an important part of treatment.

Conclusions

This work summarizes the pathogenesis, risk factor, prevention, and treatment of chronic obstructive pulmonary disease complicated with osteoporosis, and the latest progress of studies on chronic obstructive pulmonary disease and osteoporosis is discussed.

Prevalence, risk assessment, and predictors of osteoporosis among chronic obstructive pulmonary disease patients

The link between chronic obstructive pulmonary disease (COPD) and osteoporosis is unclear and yet to be understood. The study goals were to detect the prevalence of osteoporosis and investigate its predictors among COPD patients. This is a longitudinal study conducted in a tertiary care setting. During the study, patients' bone mineral density was checked, pulmonary parameters were recorded, and a risk assessment tool was validated. Based on T-score, more than 50% of subjects were osteoporotic. Spirometric parameters were significantly lower among osteoporotic patients. For the risk assessment tool, a cutoff point of 34 made the optimum balance between sensitivity and specificity (0.867 and 0.087, respectively) with a generated area under the curve of 0.934. Severe COPD patients were four times at higher risk of getting osteoporosis, forced expiratory volume (FEV) % predicted, and FEV/forced vital capacity was inversely related to the risk of osteoporosis. Patients with severe dyspnea had twice the risk of getting osteoporosis. Osteoporosis was prevalent among COPD patients, and severe COPD patients were at higher risk of getting osteoporosis.

The impact of osteoporosis and vertebral compression fractures on mortality and association with pulmonary function in COPD: A meta-analysis

OBJECTIVE

Osteoporosis is highly prevalent among patients with chronic obstructive pulmonary disease (COPD) and most commonly presents as a vertebral compression fracture (VCF). Our objective was to quantify the effect of osteoporosis and VCFs on the mortality and pulmonary function tests (PFTs), such as forced expiratory volume in 1 second (FEV₁) and forced vital capacity (FVC), of patients with COPD.

METHODS

A PubMed/Medline search was conducted using the search terms "chronic obstructive pulmonary disease", "osteoporosis" and "vertebral compression fracture". Meta-analyses were conducted to evaluate the differences in mortality and PFTs between patients with COPD with and without osteoporosis or VCFs, according to PRISMA guidelines. PROSPERO registration: CRD42019120335.

RESULTS

Of the 896 abstracts identified, 27 studies describing 7662 patients with COPD of which 1883 (24.6%) had osteoporosis or VCFs, were included. Random effects model analysis demonstrated that patients with COPD and osteoporosis or VCFs had an increased OR for mortality of 2.40 (95% CI: 1.24; 4.64, I²=89%, P<0.01), decreased FEV₁/FVC with a mean difference of -4.80% (95% CI: -6.69; -2.90, I²=83%, P<0.01) and decreased FEV₁, with a mean difference of -4.91% (95% CI: -6.51; -3.31, I²=95%, P<0.01) and -0.41 L (95% CI: -0.59; -0.24, I²=97%, P<0.01), compared to control subjects. Apart from FEV₁ (liters) in subgroup 1 (P=0.06), all subgroup analyses found significant differences between groups, as did sensitivity analysis of low risk of bias studies.

CONCLUSION

Osteoporosis and VCFs are associated with a significant reduction in survival and pulmonary function among patients with COPD.

Cigarette smoke extract promotes DNA methyltransferase 3a expression in dendritic cells, inducing Th-17/Treg imbalance via the c-Jun/allograft inflammatory factor 1 axis

Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disorder. Although numerous studies on COPD have been conducted, therapeutic strategies for COPD are limited, and its pathological mechanism is still unclear. The present study aimed to explore the role of DNA methyltransferase 3a (DNMT3a) in dendritic cells (DCs) and the possible role of the Th-17/Treg cell balance in COPD. Immature DCs (iDCs) were induced and cocultured with CD4⁺ T cells. An in vitro COPD model was established by treatment with cigarette smoke extract (CSE). DNMT3a or allograft inflammatory factor 1 (AIF1) and c-Jun N-terminal kinase (JNK) were inhibited and overexpressed, respectively, by transfection with sh-DNMT3a or sh-AIF1 and JNK overexpression plasmids. The 3- (4,5-cimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to measure cell viability. The Th17/Treg cell ratio was determined by flow cytometry. The expression levels of DNMT3a, c-Jun and AIF1 were measured using RT-qPCR or western blotting. Chromatin immunoprecipitation (CHIP) was used to confirm the interaction between c-Jun and the AIF1 promoter region. CSE stimulation promoted the expression of DNMT3a, and AIF1, and the ratio of p-c-Jun/c-Jun in iDCs. Besides, the iDC-mediated differentiation of Th17 cells was in a dose-dependent manner. However, knockdown of DNMT3a or AIF1 reversed the above effects caused by CSE. Inhibition of c-Jun signaling by treatment with the JNK inhibitor SP600125 also suppressed the iDC-mediated differentiation of Th17 cells, which was promoted by CSE. CHIP analysis showed that c-Jun could bind to the promoter region of AIF1. DNMT3a could regulate the iDC-mediated Th17/Treg balance by regulating the c-Jun/AIF1 axis.

Association of COPD with osteoporosis in male smokers: A case control study in a tertiary medical college hospital in Bangladesh

OBJECTIVES

Chronic obstructive pulmonary disease (COPD) may increase the risk of osteoporosis and resulting fractures can contribute to disability and mortality of patients. We intended to evaluate the frequency of osteoporosis in male smokers with and without COPD and study whether any correlation existed between osteoporosis and COPD.

MATERIALS AND METHODS

This case-control study was carried out in the Department of Medicine, Sylhet MAG Osmani Medical College Hospital, Sylhet, Bangladesh between July 2013 and June 2015. Seventy four male smokers with COPD and 66 age-matched male smokers without COPD were enrolled. All individuals underwent Bone Mass Densitometry (BMD) by Dual-Energy X-Ray Absorptiometry (DEXA).

RESULTS

COPD and non-COPD groups did not differ regarding age and smoking pack-years. Osteoporosis at femoral neck (48.6% versus 16.7%; p< 0.001) and lumbar spine (68.9% versus 37.9%; p< 0.01) was significantly higher in COPD compared to controls. Osteopenia did not differ significantly. Patients with COPD were 4.5 times more likely to develop osteoporosis than controls after adjusting age, smoking-pack years and BMI (adjusted OR = 4.5; 95% CI = 1.8-11.5).

CONCLUSIONS

Osteoporosis is more frequent in male smokers with COPD compared to smokers without COPD. COPD is a risk factor of osteoporosis independent of age, smoking and BMI.

Differences in bone density on chest CT according to smoking status in males without chronic obstructive lung disease

The goals of this study were to determine whether bone density measured using CT (CTBD) can show significant differences in bone loss according to smoking status and pack-years, and to examine the correlation between CTBD and bone mineral density when measured by dual-energy X-ray absorptiometry (DEXA-BMD) in males without chronic obstructive pulmonary disease (COPD). In this cross-sectional study, 1,011 males without airflow obstruction ≥50 years old were included. CTBD and DEXA-BMD were compared among groups with different smoking statuses. The correlation between CTBD and DEXA-BMD and the association of CTBD with pack-years were also investigated. CTBD of all vertebral bodies (VBs) and DEXA-BMD of all VBs without L1 showed significant differences among never, former, and current smokers. CTBD was significantly lowest in ≥30-pack-year smokers and was significantly lower in ≥30-pack-year smokers than in <15-pack-year smokers (all P < 0.05). There were significant correlations between DEXA-BMD and CTBD at all VB levels (correlation coefficient [r], 0.448~0.640; all P < 0.01). A lower CTBD had a significant association with a 15 ≤ x < 30-pack-year smoking history and ≥30-pack-year smoking history, while there was no association with never-smokers. In conclusion, CTBD demonstrated significant differences in bone quality according to smoking status and pack-years in males without COPD.

Prevalence and Risk Factors for Osteoporosis in Individuals With COPD: A Systematic Review and Meta-analysis

BACKGROUND

Osteoporosis is prevalent in individuals with COPD. Updated evidence is required to complement the previous systematic review on this topic to provide best practice. The aim of this systematic review and meta-analysis was to quantitatively synthesize data from studies with respect to the prevalence and risk factors for osteoporosis among individuals with COPD.

METHODS

EMBASE, CINAHL, MEDLINE, and PubMed databases were searched for articles containing the key words "COPD," "osteoporosis," "prevalence," and "risk factor." Eligibility screening, data extraction, and quality assessment of the retrieved articles were conducted independently by two reviewers. Meta-analyses were performed to determine osteoporosis prevalence and risk factors in individuals with COPD. Meta-regression analyses were conducted to explore the sources of heterogeneity.

RESULTS

The pooled global prevalence from 58 studies was 38% (95% CI, 34-43). The presence of COPD increased the likelihood of having osteoporosis (OR, 2.83). Other significant risk factors for osteoporosis in COPD patients were BMI < 18.5 kg/m² (OR, 4.26) and the presence of sarcopenia (OR, 3.65).

CONCLUSIONS

Osteoporosis is prevalent in individuals with COPD, and the prevalence seems to be high and similar in many countries. Patients with COPD should be screened for osteoporosis and contributing risk factors.