Metabolic syndrome and Chronic Obstructive Pulmonary Disease (COPD): The interplay among smoking, insulin resistance and vitamin D

Association between metabolic syndrome and chronic obstructive pulmonary disease development in young individuals: a nationwide cohort study

BACKGROUND

The association between metabolic syndrome (MetS) and chronic obstructive pulmonary disease (COPD) has not been studied well, particularly in young individuals. We investigated the risk of COPD development in young individuals based on MetS and its components.

METHODS

We used the Korean National Health Information Database to identify 6,891,400 individuals aged 20-39 years who participated in the national health check-up service between 2009 and 2012. Then, we identified individuals with MetS and investigated COPD development based on health insurance claims. Cox proportional hazard regression models were used to calculate the adjusted hazard ratio (aHR) for the risk of COPD development.

RESULTS

During a mean follow-up period of 8.35 years, 13,784 individuals were newly diagnosed with COPD. MetS was associated with an increased risk of COPD (aHR, 1.18; 95% confidence interval [CI], 1.11-1.24). Among the MetS components, except for hyperglycemia, abdominal obesity (aHR, 1.27; 95% CI, 1.19-1.34), hypertension (aHR, 1.05; 95% CI, 1.01-1.10), hypertriglyceridemia (aHR, 1.11; 95% CI, 1.07-1.16), and low high-density lipoprotein cholesterol levels (aHR, 1.16; 95% CI, 1.11-1.22) were significantly associated with COPD development. A higher number of MetS components correlated with an increased risk of COPD development, with the highest risk observed when all five MetS components were present (aHR, 1.55; 95% CI, 1.28-1.87).

CONCLUSION

MetS was associated with COPD development in young individuals. The risk of COPD development increased along with the increasing number of MetS components. These findings suggest that careful monitoring for COPD development is necessary in young individuals with MetS, especially those with multiple components of MetS.

Assessment of Metabolic Syndrome in Patients with Chronic Obstructive Pulmonary Disease: A 6-Month Follow-Up Study

BACKGROUND/OBJECTIVES

The association between chronic obstructive pulmonary disease (COPD) and metabolic syndrome (MetS) is a common one, with long-term therapeutic and prognostic impact. In view of the high pulmonary and cardiovascular morbidity and mortality, self-management contributes to decreasing the risk of an acute cardiac event or pulmonary decompensation.

METHODS

We conducted a prospective cohort study on 100 patients admitted to Iasi Clinical Rehabilitation Hospital who were divided into two groups according to the presence (67 patients) or absence (33 patients) of MetS. All patients benefited from multidisciplinary counseling sessions on their active role in improving modifiable cardiovascular risk factors and thus increasing quality of life. The aim of this study was to examine the impact of metabolic syndrome on lung function and the role of self-management in a 6-month follow-up period. The demographic, anthropometric, cardiovascular risk factors, and respiratory function were analyzed at baseline and at 6 months.

RESULTS

The presence of MetS was associated with higher fasting blood glucose (p = 0.004) and triglycerides (p = 0.003) but not with higher levels of interleukins or TNF-alpha. At the 6-month follow-up, abdominal circumference, forced expiratory volume in one second (FEV1), dyspnea severity, and blood pressure values improved in male patients with COPD. Systolic and diastolic blood pressure decreased in the COPD group as a whole, but especially in male patients with and without associated MetS. BMI was positively correlated with FEV1 (r = 0.389, p = 0.001) and the FEV1/forced vital capacity (FVC) ratio (r = 0.508, p < 0.001) in all COPD patients and in the MetS subgroup. In the COPD group as a whole. the six-minute walk test (6MWT) results (m) were positively correlated with FEV1 and FVC. The correlation remained significant for FVC in COPD patients with and without MetS. An increase in BMI by one unit led to an increase in TG values by 3.358 mg/dL, and the presence of metabolic syndrome led to an increase in TG values by 17.433 mg/dL.

CONCLUSIONS

In our study, MetS is a common comorbidity in patients with COPD and is associated with higher BMI, fasting glucose, and triglycerides but not with the inflammatory parameters. A mixed pulmonary-cardiovascular rehabilitation intervention leads to improvement in various parameters in both female and male COPD patients.

A Systematic Review of Metabolic Syndrome: Key Correlated Pathologies and Non-Invasive Diagnostic Approaches

Background and Objectives: Metabolic syndrome (MetS) is a condition marked by a complex array of physiological, biochemical, and metabolic abnormalities, including central obesity, insulin resistance, high blood pressure, and dyslipidemia (characterized by elevated triglycerides and reduced levels of high-density lipoproteins). The pathogenesis develops from the accumulation of lipid droplets in the hepatocyte (steatosis). This accumulation, in genetically predisposed subjects and with other external stimuli (intestinal dysbiosis, high caloric diet, physical inactivity, stress), activates the production of pro-inflammatory molecules, alter autophagy, and turn on the activity of hepatic stellate cells (HSCs), provoking the low grade chronic inflammation and the fibrosis. This syndrome is associated with a significantly increased risk of developing type 2 diabetes mellitus (T2D), cardiovascular diseases (CVD), vascular, renal, pneumologic, rheumatological, sexual, cutaneous syndromes and overall mortality, with the risk rising five- to seven-fold for T2DM, three-fold for CVD, and one and a half-fold for all-cause mortality. The purpose of this narrative review is to examine metabolic syndrome as a "systemic disease" and its interaction with major internal medicine conditions such as CVD, diabetes, renal failure, and respiratory failure. It is essential for internal medicine practitioners to approach this widespread condition in a "holistic" rather than a fragmented manner, particularly in Western countries. Additionally, it is important to be aware of the non-invasive tools available for assessing this condition. Materials and Methods: We conducted an exhaustive search on PubMed up to July 2024, focusing on terms related to metabolic syndrome and other pathologies (heart, Lung (COPD, asthma, pulmonary hypertension, OSAS) and kidney failure, vascular, rheumatological (osteoarthritis, rheumatoid arthritis), endocrinological, sexual pathologies and neoplastic risks. The review was managed in accordance with the PRISMA statement. Finally, we selected 300 studies (233 papers for the first search strategy and 67 for the second one). Our review included studies that provided insights into metabolic syndrome and non-invasive techniques for evaluating liver fibrosis and steatosis. Studies that were not conducted on humans, were published in languages other than English, or did not assess changes related to heart failure were excluded. Results: The findings revealed a clear correlation between metabolic syndrome and all the pathologies above described, indicating that non-invasive assessments of hepatic fibrosis and steatosis could potentially serve as markers for the severity and progression of the diseases. Conclusions: Metabolic syndrome is a multisystem disorder that impacts organs beyond the liver and disrupts the functioning of various organs. Notably, it is linked to a higher incidence of cardiovascular diseases, independent of traditional cardiovascular risk factors. Non-invasive assessments of hepatic fibrosis and fibrosis allow clinicians to evaluate cardiovascular risk. Additionally, the ability to assess liver steatosis may open new diagnostic, therapeutic, and prognostic avenues for managing metabolic syndrome and its complications, particularly cardiovascular disease, which is the leading cause of death in these patients.

Vitamin D Status in Women with a History of Infertility and Decreased Fecundability: A Population-Based Study

BACKGROUND

Infertility and fecundability problems have been linked with lower 25-hydroxyvitamin D (25(OH)D) concentrations, but studies conducted with small, heterogenous or selected populations have shown inconsistent results.

METHODS

This study included women at age 31 from prospective population-based Northern Finland Birth Cohort 1966. Serum 25(OH)D concentrations were evaluated between women with or without previous infertility examinations or treatments (infertility group, n = 375, reference group, n = 2051) and time to pregnancy (TTP) of over 12 months (decreased fecundability group, n = 338) with a wide range of confounders. Furthermore, 25(OH)D concentrations were also compared among reproductive outcomes.

RESULTS

The mean 25(OH)D concentration was lower and 25(OH)D < 30 nmol/L was more frequent in women with a history of infertility compared to reference group. Moreover, 25(OH)D > 75 nmol/L was more frequent in the reference group. The mean 25(OH)D concentration was lower in women who had had multiple miscarriages. Both history of infertility (β = -2.7, 95% confidence interval (CI) -4.6, -0.7) and decreased fecundability associated with lower 25(OH)D concentration (β = -4.1, 95% CI -7.4, -0.8) after adjustments. In conclusion, this population-based study demonstrated that previous infertility and decreased fecundability were associated with lower 25(OH)D.

De novo discovery of traits co-occurring with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a heterogeneous group of chronic lung conditions. Genome-wide association studies have identified single-nucleotide polymorphisms (SNPs) associated with COPD and the co-occurring conditions, suggesting common biological mechanisms underlying COPD and these co-occurring conditions. To identify them, we have integrated information across different biological levels (i.e., genetic variants, lung-specific 3D genome structure, gene expression and protein-protein interactions) to build lung-specific gene regulatory and protein-protein interaction networks. We have queried these networks using disease-associated SNPs for COPD, unipolar depression and coronary artery disease. COPD-associated SNPs can control genes involved in the regulation of lung or pulmonary function, asthma, brain region volumes, cortical surface area, depressed affect, neuroticism, Parkinson's disease, white matter microstructure and smoking behaviour. We describe the regulatory connections, genes and biochemical pathways that underlay these co-occurring trait-SNP-gene associations. Collectively, our findings provide new avenues for the investigation of the underlying biology and diverse clinical presentations of COPD. In so doing, we identify a collection of genetic variants and genes that may aid COPD patient stratification and treatment.

Correlations and diagnostic tools for metabolic syndrome (MetS) and chronic obstructive pulmonary disease (COPD)

BACKGROUND

Regarding the importance of obesity in patients with chronic obstructive pulmonary disease (COPD), we aimed to evaluate of correlation between metabolic syndrome (MetS) and COPD.

METHODS

In this cross-sectional study, 96 patients with COPD were evaluated. This study was conducted in 2016-2018. The severity of COPD was determined by Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2017 criteria. We investigated the correlations between MetS with COPD and possible diagnostic tools.

RESULTS

Of all COPD patients, 86.5% had MetS, and the means of waist circumference, fasting blood glucose, systolic and diastolic blood pressure, body mass index, and triglyceride in patients with MetS were significantly higher than the patients without MetS (P < 0.05). We showed that forced expiratory volume in 1 second (FEV1) with a 37% cutoff had 92.8% and 69.2% sensitivity and specificity, respectively (area of the curve: 0.51, 0.31-0.71).

CONCLUSION

MetS is prevalent among COPD and FEV1 could be considered as important diagnostic tool for COPD.

Mechanisms Linking COPD to Type 1 and 2 Diabetes Mellitus: Is There a Relationship between Diabetes and COPD?

Chronic obstructive pulmonary disease (COPD) patients frequently suffer from multiple comorbidities, resulting in poor outcomes for these patients. Diabetes is observed at a higher frequency in COPD patients than in the general population. Both type 1 and 2 diabetes mellitus are associated with pulmonary complications, and similar therapeutic strategies are proposed to treat these conditions. Epidemiological studies and disease models have increased our knowledge of these clinical associations. Several recent genome-wide association studies have identified positive genetic correlations between lung function and obesity, possibly due to alterations in genes linked to cell proliferation; embryo, skeletal, and tissue development; and regulation of gene expression. These studies suggest that genetic predisposition, in addition to weight gain, can influence lung function. Cigarette smoke exposure can also influence the differential methylation of CpG sites in genes linked to diabetes and COPD, and smoke-related single nucleotide polymorphisms are associated with resting heart rate and coronary artery disease. Despite the vast literature on clinical disease association, little direct mechanistic evidence is currently available demonstrating that either disease influences the progression of the other, but common pharmacological approaches could slow the progression of these diseases. Here, we review the clinical and scientific literature to discuss whether mechanisms beyond preexisting conditions, lifestyle, and weight gain contribute to the development of COPD associated with diabetes. Specifically, we outline environmental and genetic confounders linked with these diseases.

Statistical Bioinformatics to Uncover the Underlying Biological Mechanisms That Linked Smoking with Type 2 Diabetes Patients Using Transcritpomic and GWAS Analysis

Type 2 diabetes (T2D) is a chronic metabolic disease defined by insulin insensitivity corresponding to impaired insulin sensitivity, decreased insulin production, and eventually failure of beta cells in the pancreas. There is a 30–40 percent higher risk of developing T2D in active smokers. Moreover, T2D patients with active smoking may gradually develop many complications. However, there is still no significant research conducted to solve the issue. Hence, we have proposed a highthroughput network-based quantitative pipeline employing statistical methods. Transcriptomic and GWAS data were analysed and obtained from type 2 diabetes patients and active smokers. Differentially Expressed Genes (DEGs) resulted by comparing T2D patients’ and smokers’ tissue samples to those of healthy controls of gene expression transcriptomic datasets. We have found 55 dysregulated genes shared in people with type 2 diabetes and those who smoked, 27 of which were upregulated and 28 of which were downregulated. These identified DEGs were functionally annotated to reveal the involvement of cell-associated molecular pathways and GO terms. Moreover, protein–protein interaction analysis was conducted to discover hub proteins in the pathways. We have also identified transcriptional and post-transcriptional regulators associated with T2D and smoking. Moreover, we have analysed GWAS data and found 57 common biomarker genes between T2D and smokers. Then, Transcriptomic and GWAS analyses are compared for more robust outcomes and identified 1 significant common gene, 19 shared significant pathways and 12 shared significant GOs. Finally, we have discovered protein–drug interactions for our identified biomarkers.

Effectiveness and clinical benefits of new anti-diabetic drugs: A real life experience

We evaluated the clinical impact, in daily clinical practice, of sodium-glucose co-transporter-2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP1RA) therapies in patients with type 2 diabetes. Data from 500 unselected consecutive patients were retrospectively analyzed. Only those with a full assessment at baseline (T0) and after 3 (T3), 6 (T6), and 12 (T12) months of treatment with SGLT2i or GLP1RA were included in the study (n = 167). At baseline, patients had a high mean body weight (BW), abdominal circumference (AC), body mass index (BMI), and HOMA index. Despite normal C-peptide values, 39 patients were being treated with insulin (up to 120 IU/day). During therapy, a progressive improvement in BW, BMI, and AC was observed with both the molecules. Fasting glucose and glycated Hb decrease was already significant at T3 in all patients, while the HOMA index selectively improved with SGLT2i therapy. Renal function parameters remained stable regardless of the drug used. Finally, SGLT2i reduced serum uric acid and improved the lipid profile, while GLP1RA reduced serum levels of liver enzymes. Both the therapeutic regimens allowed a significant reduction or complete suspension of unnecessary insulin therapies. Our real life data confirm the results obtained from randomized clinical trials and should be taken as a warning against inappropriate use of insulin in patients with preserved β-cell function.

Metabolic syndrome in patients with COPD: Causes and pathophysiological consequences

BACKGROUND

Decreased physical activity significantly increases the probability of prevalent metabolic syndrome (MetS) with substantial impact on the expected course of COPD.

OBJECTIVE

Our research aims to assess the metabolic consequences of chronic obstructive pulmonary disease (COPD) and evaluate the prevalence of MetS and its interrelations with age, sex, comorbidities, drug intake, degree of decreased lung function, nutritional status, physical activity and quality of life.

METHODS

A cross-sectional study was performed on a random sample (n = 401) at the Department of Pulmonary Rehabilitation of the National Koranyi Institute of Pulmonology from March 1, 2019 to March 1, 2020 in Budapest, Hungary. Anthropometric and respiratory function tests and laboratory parameters of all patients were registered.

RESULTS

MetS occurred in 59.1% of COPD patients with significant gender difference (male: 49.7% female: 67.6%). Concerning BMI, the prevalence of MetS was higher with BMI≥25 kg m-2 (P < 0.0001). Patients with this syndrome had significantly worse FEV1%pred (43 (30-56) vs. 47 (36-61); P = 0.028), lower quality of life (CAT: 26 (21-32) vs. 24.5 (19-29); P = 0.049) and significantly more frequent exacerbations (2 (1-3) vs.1 (0-2); P < 0.05), than patients without MetS. The prevalence of comorbidities were higher in overweight/obese patients (BMI> 25 kg m-2).

CONCLUSIONS

In COPD patients MetS negatively affect respiratory function and quality of life and promotes exacerbations of the disease. MetS is related to nutritional status and the level of systemic inflammation in COPD patients.

Role of interluekin-6 and insulin resistance as screening markers for metabolic syndrome in patients of chronic obstructive pulmonary disease. A hospital based cross-sectional study

Chronic obstructive pulmonary disease (COPD) is usually associated with a variety of extra-pulmonary manifestations. Metabolic syndrome (MetS) is one such entity that has been scarcely studied in Indian patients. Availability of a good screening marker may help in timely detection of this co morbidity in COPD patients. We conducted a cross sectional study to evaluate the prevalence of MetS among COPD patients and to evaluate the role of Interleukin-6 and insulin resistance (as measured by HOMA-IR) as screening markers for MetS in COPD. A total of 100 stable COPD patients were evaluated for MetS using US National Cholesterol Education Program Adult Treatment Panel III (2005) guidelines. Interleukin-6 and HOMA-IR (for insulin resistance) were measured and compared between COPD patients with and without MetS. ROC analysis was done to find the best cut-off value and sensitivity and specificity of both the molecules in detecting MetS. In the results, the mean age of the study cohort was 59.9+8.7yrs (males=93). Forty five COPD patients (45%) fulfilled the criteria for MetS. Patients with MetS were comparatively younger (57.9+9.5 v/s 61.6+7.8 years; p=0.037) but had longer duration of preceding COPD (9.9+2.8 v/s 6.0+2.2 years; p<0.001) as compared to those without MetS. Both IL-6 and HOMA index were statistically higher (p<0.05) in COPD-MetS patients as compared to the other group. At cutoff value of 36.3 pg/ml for IL-6 and 1.61 for HOMA index, IL-6 and HOMA-IR had sensitivity 91.1% and 82.2% respectively in detecting MetS among COPD patients. To conclude, metabolic syndrome is a common comorbidity seen in COPD patients. Interleukin-6 has a better sensitivity than HOMA-IR in screening MetS among COPD patients.

Unrestrained eating behavior and risk of mortality: A prospective cohort study

BACKGROUND & AIMS

Unrestrained eating behavior has been thought to be a proxy for diet frequency, timing, and caloric intake. We investigated the association of unrestrained eating with mortality risk in the Nurses' Health Study prospectively.

METHODS

During follow-up (1994-2016), 21,953 deaths were documented among 63,999 eligible participants in analyses of eating anything at any time, 22,120 deaths were documented among 65,839 participants in analyses of no concern with figure change. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards models.

RESULTS

Eating anything at any time was associated with an increased mortality from cancer (overall HR, 95%CI: 1.07, 1.00-1.13; driven by gastrointestinal tract cancer: 1.30, 1.10-1.54) and respiratory disease (1.16, 1.05-1.29), and decreased cardiovascular disease-specific mortality (0.92, 0.86-0.99), compared to those without this behavior; however, no association was observed between this behavior and all-cause mortality (1.02, 0.99-1.05). Women who reported having no concern with figure change experienced higher risk of mortality from all-cause (1.08, 1.05-1.11), cancer (1.08, 1.02-1.14), and respiratory disease (1.18, 1.08-1.30), compared to those not reporting this behavior. Their combined effect was associated with a higher all-cause (1.09, 1.04-1.14), cancer-specific (overall: 1.18, 1.09-1.28; gastrointestinal tract cancer: 1.36, 1.08-1.71; lung cancer: 1.09; 1.04-1.14), and respiratory disease-specific (1.30, 1.13-1.50) mortality, and was inversely associated with cardiovascular disease-specific mortality (0.88, 0.80-0.98), compared to those exhibiting the opposite.

CONCLUSIONS

Unrestrained eating was associated with increased risk of all-cause, cancer-specific (particularly for gastrointestinal tract cancer and lung cancer), and respiratory disease-specific mortality, and decreased risk of cardiovascular disease-specific mortality.

Novel pharmacological strategies to treat cognitive dysfunction in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a major incurable global health burden and currently the 3rd largest cause of death in the world, with approximately 3.23 million deaths per year. Globally, the financial burden of COPD is approximately €82 billion per year and causes substantial morbidity and mortality. Importantly, much of the disease burden and health care utilisation in COPD is associated with the management of its comorbidities and viral and bacterial-induced acute exacerbations (AECOPD). Recent clinical studies have shown that cognitive dysfunction is present in up to 60% of people with COPD, with impairments in executive function, memory, and attention, impacting on important outcomes such as quality of life, hospitalisation and survival. The high prevalence of cognitive dysfunction in COPD may also help explain the insufficient adherence to therapeutic plans and strategies, thus worsening disease progression in people with COPD. However, the mechanisms underlying the impaired neuropathology and cognition in COPD remain largely unknown. In this review, we propose that the observed pulmonary oxidative burden and inflammatory response of people with COPD 'spills over' into the systemic circulation, resulting in damage to the brain and leading to cognitive dysfunction. As such, drugs targeting the lungs and comorbidities concurrently represent an exciting and unique therapeutic opportunity to treat COPD and cognitive impairments, which may lead to the production of novel targets to prevent and reverse the debilitating and life-threatening effects of cognitive dysfunction in COPD.

Association between insulin resistance and BMI with FEV1 in non-hypoxemic COPD out-patients

OBJECTIVES

This study was conducted to determine the impact of insulin resistance using Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) score and BMI in non-hypoxemic out-patients with COPD on FEV1 using linear and polynomial regressions and to determine their correlation.

METHODS

COPD patients of both genders were included after informed consent. Fasting blood sugar and serum insulin were done to calculate HOMA-IR, which were segregated into two groups of ≥ 3 and < 3 labeled insulin resistance present and absent, these were compared with BMI. Patients were segregated into GOLD Grade 1-4 per GOLD Guidelines and compared with HOMA-IR and BMI. Curve and linear regressions, multivariate and univariate analysis of HOMA-IR with BMI, FVC, and FEV1 were done.

RESULTS

A total of 273 subjects were inducted after informed consent. There was a linear correlation between HOMA-IR and BMI (r2 0.498, P < 0.001) and nonlinear correlation between HOMA-IR and FEV1 (r2 0. 617, P < 0.001) which showed little evidence of association above FEV1 > 60 predicted, but a clear negative association below that. Significant increase in HOMA-IR was seen from GOLD-2 to 3 and from GOLD-3 to 4 classes. The impact of HOMA-IR on FEV1 was 49.9% (P < 0.001) on FVC was 43.7%.

CONCLUSIONS

The results indicate that there is a high prevalence of IR in non-hypoxemic COPD. A nonlinear association is present between FEV1 and HOMA-IR which is most evident with FEV1 <60% predicted.

Metabolomics: small molecules that matter more

Metabolomics, an analytical study with high-throughput profiling, helps to understand interactions within a biological system. Small molecules, called metabolites or metabolomes with the size of <1500 Da, depict the status of a biological system in a different manner. Currently, we are in need to globally analyze the metabolome and the pathways involved in healthy, as well as diseased conditions, for possible therapeutic applications. Metabolome analysis has revealed high-abundance molecules during different conditions such as diet, environmental stress, microbiota, and disease and treatment states. As a result, it is hard to understand the complete and stable network of metabolites of a biological system. This review helps readers know the available techniques to study metabolomics in addition to other major omics such as genomics, transcriptomics, and proteomics. This review also discusses the metabolomics in various pathological conditions and the importance of metabolomics in therapeutic applications.

Metabolic Syndrome and Abnormal Peri-Organ or Intra-Organ Fat (APIFat) Deposition in Chronic Obstructive Pulmonary Disease: An Overview

Chronic obstructive pulmonary disease (COPD) is a common disorder with an increasing prevalence, characterised by persistent respiratory symptoms and airflow limitation. Systemic inflammation is involved in the pathogenesis of COPD and can also predispose to metabolic disorders (e.g., metabolic syndrome (MetS) and non-alcoholic fatty liver disease (NAFLD)). Such comorbidities can negatively affect COPD outcomes, cardiovascular risk, and quality of life. Apart from NAFLD, abnormal peri-organ or intra-organ fat (APIFat) could be considered as markers for cardiometabolic diseases and even for COPD. The present narrative review considers the associations of COPD with MetS, NAFLD, and other APIFat, including epicardial, perirenal, peripancreatic, and intramuscular adipose tissue. Further research is needed to define these relationships and identify any potential clinical implications.

Prevalence of metabolic syndrome in patients with chronic obstructive pulmonary disease: An observational study in South Indians

BACKGROUND AND AIMS

Metabolic syndrome (MetS) has a significant association with airflow obstruction and physical inactivity, which are the relevant extra-pulmonary markers of chronic obstructive respiratory disease (COPD). This study aimed to estimate the prevalence of MetS and its correlation with comorbidities and health related quality of life (HRQoL) in South Indian patients with COPD.

METHODS

A cross-sectional study was conducted among the 76 COPD patients. Pulmonary function test (PFT) and parameters for MetS such as waist circumference, blood pressure, fasting blood glucose, triglycerides (TGs) and high density lipoprotein cholesterol (HDL-C) levels of COPD patients were measured. HRQoL was calculated using Saint George Respiratory Questionnaire (SGRQ).

RESULTS

54% of COPD patients were presented with MetS especially in stage II and III. TGs and HDL-C were significantly associated with the severity of COPD (p < 0.05), while waist circumference, TGs and HDL-C were significantly (p < 0.05) correlated with PFT. Symptom, activity, impact and total scores of SGRQ was increased statistically (p < 0.05) in COPD patients with MetS than without MetS.

CONCLUSION

According to our findings, screening the grade II and III COPD patients for the presence of MetS is a reasonable option. The results of this study should be confirmed with a larger sample of population.

Perspectives of nonalcoholic fatty liver disease research: a personal point of view

Rational government of patient fluxes from primary care to hepatology clinic is a priority of nonalcoholic fatty liver disease (NAFLD) research. Estimating pre-test probability of disease, risk of fibrosis progression, and exclusion of competing causes of liver disease must be addressed. Here we propose a novel taxonomic classification of NAFLD based on hepatic, pathogenic and systemic features of disease in the individual patient. The variable course of disease in any given patient remains a clinical enigma. Therefore, future studies will have to better characterize the role of genetic polymorphisms, family and personal history, diet, alcohol, physical activity and drugs as modifiers of the course of disease and clues to the early diagnosis of hepatocellular carcinoma. A better understanding of these, together with a taxonomic diagnosis, may prompt a more accurate personalization of care. For example, understanding the putative role of psycho-depression in NAFLD promises to revolutionize disease management in a proportion of cases. Similarly, sex differences in outcome and response to treatment are insufficiently characterized. More studies are awaited regarding those forms of NAFLD which occur secondary to endocrine derangements. The intersections between NAFLD and the lung must better be defined. These include the bi-directional associations of NAFLD and chronic obstructive pulmonary disease and sleep apnoea syndrome, as well as the totally unexplored chapter of NAFLD and coronavirus disease 2019 (COVID-19). Finally, the therapeutic roles of intermittent fasting and anticoagulation must be assessed. In conclusion, over the last 20 years, NAFLD has taught us a lot regarding the pathogenic importance of insulin resistance, the limitations of correcting this in the treatment of NAFLD, the root causes of diabetes and the metabolic syndrome, sex differences in disease and the role of nuclear receptors. However, the overwhelming COVID-19 pandemic is now expected to reset the priorities of public health.

The Effect of Metabolic Syndrome Status on Lung Function and Patient-reported Outcomes in Patients with COPD Receiving Nebulized Glycopyrrolate

Background

Concurrent chronic obstructive pulmonary disease (COPD) and metabolic syndrome (MetS) represent an important clinical phenotype with overlapping symptomology. The effect of MetS in COPD patients was assessed following treatment with nebulized glycopyrrolate (GLY; administered via eFlow® Closed System Nebulizer).

Methods

Posthoc analyses were performed on pooled lung function, patient-reported outcome (PRO) and safety data by MetS status from patients treated with placebo, GLY 25 and 50 mcg twice daily in two 12-week studies (GOLDEN 3 and 4; N=1293). Patients with MetS were characterized as having ≥ 3 of hypertension, hyperlipidemia, diabetes, body mass index (BMI) > 30 kg/m² risk factors. The results are presented for the Food and Drug Administration-approved GLY 25 mcg dose.

Results

A total of25% of patients met MetS criteria.At baseline, the MetS subgroup had higher BMIs, more ex-smokers, greater incidences of cardiovascular risk factors, and MetS-specific risk factors were 2-14 times higher than non-MetS. At 12 weeks, GLY produced significant, clinically important improvements (MetS: 0.121 L; non-MetS: 0.083 L) in trough forced expiratory volume in 1 second. In the non-MetS group, significant improvements occurred in the St George's Respiratory Questionnaire (MetS: -2.28, p=0.157; non-MetS: -3.71) and Evaluating Respiratory Symptoms in COPD tool (MetS: 0.42, p=0.574; non-MetS: -1.61) total scores. Incidence of adverse events was similar with GLY versus placebo regardless of MetS status.

Conclusion

GLY was well-tolerated and significantly improved lung function regardless of MetS status, while significant PRO improvements occurred in non-MetS patients. These results highlight the importance of comorbidities on bronchodilator responses and patient symptoms in COPD patients.

Metabolic Syndrome in Early Chronic Obstructive Pulmonary Disease: Gender Differences and Impact on Exacerbation and Medical Costs

Background

Metabolic syndrome (MetS) is a well-known comorbidity of chronic obstructive pulmonary disease (COPD). However, their interrelationship, particularly in early COPD, remains unclear. Therefore, we aimed to assess the prevalence and clinical characteristics of MetS in patients with early COPD, and to explore the impact of MetS on the frequency of COPD exacerbations and associated medical costs.

Patients and methods

We retrospectively enrolled 43,874 subjects from the KNHANES, including 2164 patients with early COPD (≥40 years old), recorded smoking history, and Global Initiative for Chronic Obstructive Lung Disease spirometric grade I or II, with data linked to the NHI database. We extracted and analyzed data regarding health-care utilization and medical costs for 5 years (2007 to 2012).

Results

Among 2164 patients with early COPD, the prevalence of MetS was 31.2%, and it was higher in women than in men (35.1% vs. 26.6%; P<0.001). Patients with MetS were older and had lower pulmonary function and greater number of comorbidities. The frequency of moderate-to-severe COPD exacerbations for 5 years was significantly higher in women with MetS than in those without MetS (5.8/year vs. 4.9/year; P=0.02). After adjusting for confounding factors, the risk for moderate-to-severe exacerbation was significantly greater in women with MetS (IRR, 1.17; 95% CI, 1.01 to 1.36; P=0.03). COPD exacerbations leading to hospitalization and medical expenses were also higher in women with MetS than in those without MetS.

Conclusion

MetS is more prevalent in women with early COPD. MetS increased the frequency of exacerbations and the medical costs in women with early COPD.

Impact of Vitamin D on Physical Efficiency and Exercise Performance-A Review

Vitamin D deficiency amongst athletes and the general population seems to be a prominent problem. The most recognized role of vitamin D is its regulation of calcium homeostasis; there is a strong relationship between vitamin D and bone health. Moreover, its concentrations are associated with muscle function and immune response in both the general and athletic populations. Vitamin D level is strongly connected with the presence of VDRs (vitamin D receptors) in most human extraskeletal cells. Expression of multiple myogenic transcription factors enhancing muscle cell proliferation and differentiation is caused by an exposure of skeletal muscles to vitamin D. The aim of this review is to summarize current understanding of the significance of vitamin D on exercise performance and physical efficiency, as well to analyze the impact of vitamin D on multiple potential mechanisms. More high-quality research studies, considering free 25(OH)D as a better marker of vitamin D status, the baseline level of 25(OH)D and multiple pathways of vitamin D acting and usage in athletes are required.

Systemic inflammation in patients of chronic obstructive pulmonary disease with metabolic syndrome

Context:

India has 18% of the global population and an increasing burden of chronic respiratory diseases. The prevalence of Metabolic syndrome (MS) was found to be as high as 39.7% among Indian population. Metabolic syndrome is found to be more common in Chronic Obstructive Pulmonary Disease (COPD) when compared to the general population. This study was done to assess the prevalence of metabolic syndrome in COPD and the association of systemic inflammation in COPD patients with metabolic syndrome.

Methodology:

This study enrolled 150 consecutive consenting patients of stable COPD attending the outpatient pulmonology department. Detailed history, clinical examination, spirometry, and relevant routine laboratory investigations including complete blood count, fasting blood sugar, and lipid profile were done. In addition, hsCRP, Serum lactate and Vitamin D level was assessed in all patients. Diagnosis of COPD and Metabolic syndrome was done according to GOLD guidelines, 2018 and the International Diabetes Federation criteria respectively.

Result:

The prevalence of metabolic syndrome was found to be 27.3% in our COPD patients. The frequency of metabolic syndrome in GOLD stage I, II, III, and IV was 75%, 32%, 17%, and 13.5%, respectively. Logistic regression analysis showed a significant relationship of blood leucocyte count (OR = 0.342, CI = 0.171-0.686), hs-CRP (OR = 0.020, CI = 0.003-0.122), pack years (OR = 1.083, CI = 1.026-1.14) and vitamin D levels (OR = 1.219, CI = 1.093-1.359) with metabolic syndrome in COPD patients.

Conclusion:

Metabolic syndrome is a co-morbidity that is very often overlooked in patients of COPD. Systemic inflammation which is a common characteristic of both COPD and Metabolic syndrome has been found to be an important contributor towards cardiovascular morbidity and mortality.

Validation of Predictive Metabolic Syndrome Biomarkers of World Trade Center Lung Injury: A 16-Year Longitudinal Study

BACKGROUND

Metabolic syndrome (MetSyn) predicted future development of World Trade Center lung injury (WTC-LI) in a subgroup of firefighters who never smoked and were male. An intracohort validation of MetSyn as a predictor of WTC-LI is examined in the cohort exposed to the World Trade Center (WTC) that has been followed longitudinally for 16 years.

METHODS

Results of pulmonary function tests (n = 98,221) in workers exposed to the WTC (n = 9,566) were evaluated. A baseline cohort of firefighters who had normal FEV1 before 9/11 and who had had serum drawn before site closure on July 24, 2002 (n = 7,487) was investigated. Case subjects with WTC-LI (n = 1,208) were identified if they had at least two measured instances of FEV1 less than the lower limit of normal (LLN). Cox proportional hazards modeled early MetSyn biomarker ability to predict development of FEV1 less than the LLN.

RESULTS

Case subjects were more likely to smoke, be highly exposed, and have MetSyn. There was a significant exposure dose response; the individuals most highly exposed had a 30.1% increased risk of developing WTC-LI, having MetSyn increased risk of developing WTC-LI by 55.7%, and smoking increased risk by 15.2%. There was significant interaction between smoking and exposure.

CONCLUSIONS

We validated the usefulness of MetSyn to predict future WTC-LI in a larger population of individuals who were exposed. MetSyn defined by dyslipidemia, insulin resistance, and cardiovascular disease suggests that systemic inflammation can contribute to future lung function loss.

Waist Circumference and Spirometric Measurements in Chronic Obstructive Pulmonary Disease

OBJECTIVES

The aim of this study was to evaluate whether the waist circumference of patients with chronic obstructive pulmonary disease (COPD), had an impact on lung function.

METHODS

There were 180 patients with COPD recruited into this prospective cross-sectional study. The age, weight, body mass index and waist circumference (WC) were measured. Spirometry parameters including forced vital capacity (FVC), and forced expiratory volume in the first second (FEV1), were measured and FEV1/FVC calculated.

RESULTS

The mean FEV1/FVC in both normal weight and overweight patients, did not statistically significantly correlate with WC. The COPD assessment test, positively correlated with WC ( p = 0.031). A positive correlation with body mass index ( p < 0.001), smoking ( p = 0.027), and global initiative for chronic obstructive lung disease score ( p = 0.009), were observed to positively associate with WC. WC, age, C-reactive protein, duration of disease, and gender (male), were observed to be statistically significant risk factors for the severity of COPD.

CONCLUSION

WC was not observed to impact upon lung function in this study but it was a predictive factor for COPD severity in patients.

Pathobiological mechanisms underlying metabolic syndrome (MetS) in chronic obstructive pulmonary disease (COPD): clinical significance and therapeutic strategies

Chronic obstructive pulmonary disease (COPD) is a major incurable global health burden and is currently the 4th largest cause of death in the world. Importantly, much of the disease burden and health care utilisation in COPD is associated with the management of its comorbidities (e.g. skeletal muscle wasting, ischemic heart disease, cognitive dysfunction) and infective viral and bacterial acute exacerbations (AECOPD). Current pharmacological treatments for COPD are relatively ineffective and the development of effective therapies has been severely hampered by the lack of understanding of the mechanisms and mediators underlying COPD. Since comorbidities have a tremendous impact on the prognosis and severity of COPD, the 2015 American Thoracic Society/European Respiratory Society (ATS/ERS) Research Statement on COPD urgently called for studies to elucidate the pathobiological mechanisms linking COPD to its comorbidities. It is now emerging that up to 50% of COPD patients have metabolic syndrome (MetS) as a comorbidity. It is currently not clear whether metabolic syndrome is an independent co-existing condition or a direct consequence of the progressive lung pathology in COPD patients. As MetS has important clinical implications on COPD outcomes, identification of disease mechanisms linking COPD to MetS is the key to effective therapy. In this comprehensive review, we discuss the potential mechanisms linking MetS to COPD and hence plausible therapeutic strategies to treat this debilitating comorbidity of COPD.

Endothelial Progenitor Cells as Pathogenetic and Diagnostic Factors, and Potential Targets for GLP-1 in Combination with Metabolic Syndrome and Chronic Obstructive Pulmonary Disease

In clinical practice, there are patients with a combination of metabolic syndrome (MS) and chronic obstructive pulmonary disease (COPD). The pathological mechanisms linking MS and COPD are largely unknown. It remains unclear whether the effect of MS (possible obesity) has a major impact on the progression of COPD. This complicates the development of effective approaches for the treatment of patients with a diagnosis of MS and COPD. Experiments were performed on female C57BL/6 mice. Introduction of monosodium glutamate and extract of cigarette smoke was modeled to simulate the combined pathology of lipid disorders and emphysema. Biological effects of glucagon-like peptide 1 (GLP-1) and GLP-1 on endothelial progenitor cells (EPC) in vitro and in vivo were evaluated. Histological, immunohistochemical methods, biochemical methods, cytometric analysis of markers identifying EPC were used in the study. The CD31⁺ endothelial cells in vitro evaluation was produced by Flow Cytometry and Image Processing of each well with a Cytation™ 3. GLP-1 reduces the area of emphysema and increases the number of CD31⁺ endothelial cells in the lungs of mice in conditions of dyslipidemia and damage to alveolar tissue of cigarette smoke extract. The regenerative effects of GLP-1 are caused by a decrease in inflammation, a positive effect on lipid metabolism and glucose metabolism. EPC are proposed as pathogenetic and diagnostic markers of endothelial disorders in combination of MS with COPD. Based on GLP-1, it is proposed to create a drug to stimulate the regeneration of endothelium damaged in MS and COPD.

Vitamin D and health in the Mediterranean countries

Vitamin D, traditionally well known for its role in maintaining optimal health through its contribution to calcium metabolism and skeletal health, has received increased attention over the past two decades, with considerable focus being placed on its nonskeletal benefits. This paper is a narrative review of the nonskeletal health benefits of vitamin D, of particular interest to inhabitants of Mediterranean countries, namely, autism, cancer, cardiovascular disease, chronic obstructive pulmonary disease, dental caries, diabetes mellitus, erectile dysfunction, hypertension, metabolic syndrome, respiratory tract infections, all-cause mortality, and pregnancy and birth outcomes, because of the relatively high incidence and/or prevalence of these disorders in this region. Currently, the best evidence is coming out of observational studies related to serum 25-hydroxyvitamin D [25(OH)D] concentrations. Vitamin D clinical trials have generally been poorly designed and conducted, usually being based on vitamin D dose rather than 25(OH)D concentration. The optimal 25(OH)D concentration is above 75 nmol/l (30 ng/ml), with even better health outcomes in the range of 100-150 nmol/l. Achieving these concentrations with vitamin D₃ supplements will require 1000-4000 IU/day of vitamin D₃. Sensible sun exposure should also be encouraged. Countries should also consider fortifying grain and dairy products with vitamin D₃.

Smoking during pregnancy reduces vitamin D levels in a Finnish birth register cohort

OBJECTIVE

Maternal vitamin D level in pregnancy may have implications for both the mother and fetus. Deficiency of vitamin D has been linked to several pregnancy complications and fetal skeletal health. Smoking has been associated with reduced serum level of the vitamin D metabolite, 25-hydroxyvitamin D (25(OH)D).

DESIGN

A nested case-control study within the Finnish Maternity Cohort, a population-based cohort which includes first-trimester sera from 98 % of pregnancies in Finland since 1987. The selection consisted of women with uncomplicated pregnancies. We studied serum concentration of 25(OH)D in 313 non-smoking and forty-six self-reported smoking pregnant women.

SETTING

We hypothesize that pregnant smokers may have an increased risk of low 25(OH)D levels especially during winter months.

PARTICIPANTS

A control group from an unpublished pregnancy complication study consisting of 359 uncomplicated pregnancies. Individuals who reported that they do not smoke were considered 'non-smokers' (n 313) and those who reported continued smoking after the first trimester of pregnancy were considered 'smokers' (n 46).

RESULTS

Smokers had significantly lower levels of 25(OH)D irrespective of sampling time (P<0·0001). Furthermore, during the low sun-exposure season, only 14 % of smokers met the guideline level of 40 nmol/l for serum 25(OH)D in comparison with 31 % of non-smokers.

CONCLUSIONS

Expectant mothers who smoke have an increased risk of vitamin D deficiency during low sun-exposure months in northern regions. Further studies are needed to assess the associated risks for maternal and fetal health as well as possible long-term implications for the infant.

Decreased lung function is associated with risk of developing non-alcoholic fatty liver disease: A longitudinal cohort study

BACKGROUND

Decreased lung function is associated with non-alcoholic fatty liver disease (NAFLD), based on linking mechanisms such as insulin resistance and systemic inflammation However, its association with the risk of developing NAFLD is unclear. Our aim was to investigate whether baseline lung function is associated with incident NAFLD in middle-aged healthy Koreans.

METHODS

A cohort study of 96,104 subjects (mean age: 35.7 years) without NAFLD were followed up from 2002 to 2015. NAFLD was diagnosed by ultrasound after the exclusion of other possible causes of liver diseases. Baseline percent predicted forced expiratory volume in one second (FEV1%) and forced vital capacity (FVC%) were categorized in quartiles. Adjusted hazard ratios (aHR) and 95% confidence intervals (CIs) (using the highest quartile as reference) were calculated for incident NAFLD at follow-up, controlling for covariates and potential confounders.

RESULTS

During 579,714.5 person-years of follow-up, 24,450 participants developed NAFLD (incidence rate, 42.2 per 1,000 person-years). The mean follow-up period was 5.9±3.4 years. Regardless of smoking history, the risk for incident NAFLD increased with decreasing quartiles of FEV1 (%) and FVC (%) in a dose-response manner (p for trend<0.001). In never smokers, the aHRs (95% CIs) for incident NAFLD were 1.15 (1.08-1.21), 1.11 (1.05-1.18), and 1.08 (1.02-1.14) in quartiles 1-3 for FEV1 (%) and 1.12 (1.06-1.18), 1.11 (1.05-1.18), and 1.09 (1.03-1.15) in quartiles 1-3 for FVC (%), compared with the highest quartile reference. Similar inverse association was present in smoke-exposed subjects (aHR for incident NAFLD were 1.14, 1.21, 1.13 and 1.17, 1.11, 1.09 across FEV1(%) and FVC(%) quartile in increasing order, respectively).

CONCLUSIONS

Reduced lung function was a risk factor for incident NAFLD in a large middle-aged Korean cohort with over half a million person-years of follow-up.

Hyperhomocysteinemia is an independent risk factor of atherosclerosis in patients with metabolic syndrome

BACKGROUND

Metabolic syndrome (MetS) is a clinical condition potentially promoting the development of atherosclerotic disease. To date, the clinical impact of elevated serum homocysteine (Hcy) levels in MetS is still under discussion. The aim of this cross sectional study was to evaluate the relationship between MetS and hyperhomocysteinemia and the potential role of Hcy in the pathogenesis of atherosclerotic complications of MetS.

METHODS

We recruited 300 outpatients with MetS. All patients underwent a medical history collection, physical examination, blood sampling and carotid ultrasound echo-color Doppler. According to Hcy levels, MetS patients were divided into two groups: "normal" (< 10.7 μmol/l; n = 140, group 1) and "high" Hcy (≥ 10.7 μmol/l; n = 160, group 2). Comparisons between groups were made by Student's t-test or Chi-square test. The effects of potential covariates on group differences were evaluated by general linear models. The relationships between continuous variables were assessed by simple or multiple correlation and by linear regression. Multiple regression models were built to evaluate the effects of Hcy, together with other potential risk factors, on carotid atherosclerosis.

RESULTS

Patients with high Hcy were predominantly male and slightly older than group 1 patients. Smokers and non-smokers exhibited similar Hcy levels, nor was a statistical relationship between pack-years and Hcy observed. Group 2 showed lower levels of folic acid, vitamin D, high density lipoprotein (HDL)-cholesterol and glomerular filtration rate (e-GFR) than group 1, but higher levels of C-peptide, uric acid and triglycerides. In all patients, Hcy was positively correlated with C-peptide and uric acid and negatively with folic acid and e-GFR. Intima-media thickness (IMT) and carotid stenosis degree were significantly higher in patients with high Hcy and a positive relationship between Hcy and both IMT and carotid stenosis was detected in all patients. Finally, Hcy atherogenic effects were independent of other well-known atherosclerosis risk factors.

CONCLUSIONS

Our results highlight a link between MetS and hyperhomocysteinemia and a direct effect of Hcy on atherogenic process during MetS. Early correction of folic acid levels may contribute to prevent cardiovascular complications in MetS patients.

Insulin translates unfavourable lifestyle into obesity

Lifestyle factors conferring increased diabetes risk are associated with elevated basal insulin levels (hyperinsulinaemia). The latter predicts later obesity in children and adolescents.A causal role of hyperinsulinaemia for adipose tissue growth is probable because pharmacological reduction of insulin secretion lowers body weight in people who are obese. Genetic inactivation of insulin gene alleles in mice also lowers their systemic insulin levels and prevents or ameliorates high-fat diet-induced obesity. Hyperinsulinaemia causes weight gain because of a physiological property of insulin. Insulin levels that are on the high side of normal, or which are slightly elevated, are sufficient to suppress lipolysis and promote lipogenesis in adipocytes. The effect of insulin on glucose transport or hepatic glucose production requires six or two times higher hormone levels, respectively.It seems justified to suggest a lifestyle that avoids high insulin levels in order to limit anabolic fat tissue activity.

Association of Metabolic Syndrome with the Severity of Airflow Obstruction in Patients with Chronic Obstructive Pulmonary Disease

BACKGROUND

Metabolic Syndrome (MetS) is common in Chronic Obstructive Pulmonary Disease (COPD) patients but their association is still an unsettled issue. The aim of this study was to determine the association of MetS with the severity of airflow obstruction.

METHODOLOGY

This was a cross-sectional analytic study of 157 patients with COPD. They were classified using the Global Initiative for Chronic Obstructive Lung Diseases (GOLD). MetS was assessed using two well-recognized criteria. Demographics, clinical data, lifestyle-related characteristics, fasting blood sugar (FBS) and lipid profile were obtained. Multiple logistic regression was used to determine the association of MetS with the severity of airflow obstruction.

RESULTS

40.13% and 17.20% of patients had MetS using the NCEP/ATP III-AHA/NHBLI and IDF criteria, respectively. MetS was not associated with severity of airflow obstruction. Of the MetS components, only elevated blood pressure (BP) was significantly associated with severity of airflow obstruction (GOLD II: OR=3.28, p<0.001; GOLD III: OR=4.04, p=0.2; GOLD IV: OR=6.21, p=0.04). Elevated FBS was also associated with GOLD IV (OR=16.09, p=0.02). Significant factors associated with MetS in COPD patients were body mass index, inhaled steroid, number of pack-years, and GOLD II.

CONCLUSION

MetS is not associated with severity of airflow obstruction. Only certain components of MetS showed significant associations such as elevated BP with GOLD II-IV and elevated FBS with GOLD IV.

Physiopathological relationship between chronic obstructive pulmonary disease and insulin resistance

PURPOSE

Chronic obstructive pulmonary disease (COPD) is characterized by persistent and progressive airflow obstruction that is associated with an abnormal chronic inflammatory response in the airways and lungs to noxious particles. COPD often leads to physical inactivity and deconditioning that added to inappropriate/excessive inflammatory responses leads to systemic consequences. Studies have shown that metabolic syndrome and manifested diabetes are more frequent in COPD than in healthy subjects; a possible explanation is that different pathophysiological aspects of COPD can lead to insulin resistance. Thus, this mini-review aims to present the main studies suggesting a pathophysiological relationship between COPD and insulin resistance.

METHODS

A review of literature was conducted using PubMed and Web of Science databases with the aim of searching for studies supporting a relationship between COPD and insulin resistance.

RESULTS

A physiopathological relationship between COPD and insulin resistance was found, supported in part due to common risk factors presented by these two conditions, such as smoking and physical inactivity. Also, systemic effects (worsening of physical inactivity and sedentary behavior, inflammation and oxidative stress, body composition abnormalities) and the corticosteroid treatment of patients with COPD may play a role.

CONCLUSION

Patients with COPD should be screened for abnormalities in insulin sensitivity in order to reduce morbidity and improve health status in this population.

Can muscle protein metabolism be specifically targeted by nutritional support and exercise training in chronic obstructive pulmonary disease?

Chronic obstructive pulmonary disease (COPD) associates with several extra-pulmonary effects. Muscle dysfunction and wasting is one of the most prominent extra-pulmonary effects and contributes to exercise limitation and health related quality of life (HRQoL), morbidity as well as mortality. The loss of muscle mass is characterised by an impaired balance between protein synthesis (anabolism) and protein breakdown (catabolism) which relates to nutritional disturbances, muscle disuse and the presence of a systemic inflammation, among other factors. Current approaches to reverse skeletal muscle dysfunction and wasting attain only modest improvements. The development of new therapeutic strategies aiming at improving skeletal muscle dysfunction and wasting are needed. This requires a better understanding of the underlying molecular pathways responsible for these abnormalities. In this review we update recent research on protein metabolism, nutritional depletion as well as physical (in)activity in relation to muscle wasting and dysfunction in patients with COPD. We also discuss the role of nutritional supplementation and exercise training as strategies to re-establish the disrupted balance of protein metabolism in the muscle of patients with COPD. Future areas of research and clinical practice directions are also addressed.