Metabolic syndrome, insulin resistance and systemic inflammation as risk factors for reduced lung function in Korean nonsmoking males

Increased Apolipoprotein B/Apolipoprotein A-I Ratio Is Associated With Decline in Lung Function in Healthy Individuals: The Kangbuk Samsung Health Study

BACKGROUND

Lung dysfunction and high apolipoprotein B/apolipoprotein A-I (apoB/apoA-I) ratio are both recognized risk factors for cardiovascular disease. However, few studies have examined the association between the apoB/ApoA-I ratio and lung function. Therefore, we investigated whether this ratio is associated with decreased lung function in a large healthy cohort.

METHODS

We performed a cohort study on 68,418 healthy Koreans (34,797 males, mean age: 38.1 years) who underwent a health examination in 2019. ApoB/apoA-I ratio was categorized into quartiles. Spirometric values at the fifth percentile in our population were considered the lower limit of normal (LLN), which was used to define lung function impairment. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs), using the lowest quartile as the reference, were estimated to determine lung function impairment.

RESULTS

Mean apoB/apoA-I ratio was 0.67 ± 0.21. Subjects with the highest quartile of this ratio had the lowest predicted forced expiratory volume in one second (FEV1%) and forced vital capacity (FVC%) after controlling for covariates (P < 0.001). However, FEV1/FVC ratio was not significantly different among the four quartiles (P = 0.059). Compared with the lowest quartile (Q1, reference), the aORs (95% CI) for FEV1% < LLN across increasing quartiles (from Q2 to Q4) were 1.216 (1.094-1.351), 1.293 (1.156-1.448), and 1.481 (1.311-1.672) (P for trend < 0.001), respectively. Similarly, the aORs for FVC% < LLN compared with the reference were 1.212 (1.090-1.348), 1.283 (1.147-1.436), and 1.502 (1.331-1.695) with increasing quartiles (P for trend < 0.001). However, the aORs for FEV1/FVC < LLN were not significantly different among groups (P for trend = 0.273).

CONCLUSION

High apoB/apoA-I ratio was associated with decreased lung function. However, longitudinal follow-up studies are required to validate our findings.

The Impact of Metabolic Syndrome Risk Factors on Lung Function Impairment: Cross-Sectional Study

BACKGROUND

Metabolic syndrome (MetS) is a constellation of risk factors increasingly present in the world's population. People with this syndrome are at an increased risk of cardiovascular disease and type 2 diabetes mellitus. Moreover, evidence has shown that it affects different organs. MetS and its risk factors are independently associated with impaired lung function, which can be quantified through spirometric variables.

OBJECTIVE

This study aims to determine whether a high number of MetS criteria is associated with increased lung function decline.

METHODS

We conducted a descriptive cross-sectional study with a random sample of 1980 workers. Workers with acute respiratory pathology (eg, influenza), chronic respiratory pathology (eg, chronic bronchitis), or exposure to substances harmful to the lungs (eg, organic and inorganic dust) were not included. MetS was established based on harmonized criteria, and lung function was assessed according to spirometric variables. On the basis of these, classification into restrictive lung disease (RLD), obstructive lung disease, and mixed lung disease (MLD) was performed. In addition, the association between MetS and lung function was established based on analysis of covariance, linear trend analysis, and multiple linear regression.

RESULTS

MetS was associated with worse lung function according to all the spirometric parameters analyzed (percentage of predicted forced expiratory volume in 1 second: mean 83, SD 13.8 vs mean 89.2, SD 12.8; P<.001 and percentage of predicted forced vital capacity: mean 85.9, SD 11.6 vs mean 92, SD 11.3; P<.001). Moreover, those diagnosed with MetS had a higher prevalence of lung dysfunction (41% vs 21.9%; P<.001), RLD (23.4% vs 11.2%; P<.001), and MLD (7.3% vs 2.2%; P<.001). Furthermore, an increasing number of MetS criteria was associated with a greater impairment of pulmonary mechanics (P<.001). Similarly, with an increasing number of MetS criteria, there was a significant linear trend (P<.001) in the growth of the prevalence ratio of RLD (0 criteria: 1, 1: 1.46, 2: 1.52, 3: 2.53, 4: 2.97, and 5: 5.34) and MLD (0 criteria: 1, 1: 2.68, 2: 6.18, 3: 9.69, and 4: 11.37). Regression analysis showed that the alteration of all MetS risk factors, adjusted for various explanatory variables, was significantly associated with a worsening of spirometric parameters, except for forced expiratory volume in 1 second/forced vital capacity.

CONCLUSIONS

The findings have shown that an increase in cardiometabolic risk factors is associated with a more significant worsening of spirometric variables and a higher prevalence of RLD and MLD. As spirometry could be a crucial tool for monitoring patients at risk of developing chronic pathologies, we conclude that this inexpensive and easily accessible test could help detect changes in lung function in patients with cardiometabolic disorders. This highlights the need to consider the importance of cardiometabolic health in lung function when formulating public health policies.

The impact of insulin resistance on the association between metabolic syndrome and lung function: the Kangbuk Samsung Health Study

BACKGROUND/OBJECTIVE

Metabolic syndrome (MS) is related to lung dysfunction. However, its impact according to insulin resistance (IR) remains unknown. Therefore, we evaluated whether the relation of MS with lung dysfunction differs by IR.

SUBJECT/METHODS

This cross-sectional study included 114,143 Korean adults (mean age, 39.6 years) with health examinations who were divided into three groups: metabolically healthy (MH), MS without IR, and MS with IR. MS was defined as presence of any MS component, including IR estimated by HOMA-IR ≥ 2.5. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for lung dysfunction were obtained in MS, MS without IR, and MS with IR groups compared with the MH (reference) group.

RESULTS

The prevalence of MS was 50.7%. The percent predicted forced expiratory volume in 1 s (FEV1%) and forced vital capacity (FVC%) showed statistically significant differences between MS with IR and MH and between MS with IR and MS without IR (all P < 0.001). However, those measures did not vary between MH and MS without IR (P = 1.000 and P = 0.711, respectively). Compared to MH, MS was not at risk for FEV1% < 80% (1.103 (0.993-1.224), P = 0.067) or FVC% < 80% (1.011 (0.901-1.136), P = 0.849). However, MS with IR was clearly associated with FEV1% < 80% (1.374 (1.205-1.566) and FVC% < 80% (1.428 (1.237-1.647) (all p < 0.001), though there was no evident association for MS without IR (FEV1%: 1.078 (0.975-1.192, P = 0.142) and FVC%: 1.000 (0.896-1.116, p = 0.998)).

CONCLUSION

The association of MS with lung function can be affected by IR. However, longitudinal follow-up studies are required to validate our findings.

Pulmonary Function in Metabolic Syndrome: A Meta-Analysis

Background: This study aims to systematically evaluate the association between metabolic syndrome (MS) and pulmonary function through meta-analysis. Methods: Electronic databases, including PubMed, Embase, Web of Science, and Cochrane Library, were systematically searched to obtain articles associated with MS and lung function published before December 31, 2021. According to the including and excluding criteria, certain studies were obtained and data were extracted. The Newcastle Ottawa Scale was used to evaluate the quality of the studies. A pooled standardized mean difference (SMD) was calculated by means of random-effects meta-analysis. Different effect models were used according to the heterogeneity. Meta-regression and sensitivity analyses were performed to examine the possible sources of heterogeneity. The Begg's funnel plot and Egger's test were used to evaluate publication bias. Analyses were performed using Stata MP, version14.0 (StataCorp LP, College Station, TX, USA). Results: A total of 15 studies, involving 10,285 cases of MS and 25,416 cases of control, were included in this meta-analysis on the relationship between MS and forced vital capacity (FVC). The pooled SMD for FVC was -0.247 (95% CI = -0.327 to -0.2167, P < 0.001) using random effect model, indicating the decrease of FVC in the patients with MS. In the same studies, the pooled SMD for forced expiratory volume in 1 sec (FEV₁) was -0.205 (95% CI = -0.3278 to -0.133, P < 0.001), indicating the decrease of FEV₁ also existed in the MS cases. A total of 13 studies, involving 8167 cases of MS and 19,788 cases of control, were included in this meta-analysis on the relationship between MS and FEV₁/FVC. The pooled SMD for FEV₁/FVC was 0.011 (95% CI = -0.072 to 0.093, P = 0.798) using random effect model, indicating that there was no significant difference between the patients with MS and the control. After introducing the diastolic blood pressure and glycemia into the regression model of the relationship between MS and FVC, the variance of the studies (tau2) decreased from 0.0190 to 0.006694 and 0.007205, which could explain 66.70% and 78.04% of the sources of heterogeneity, and the P values were 0.038 and 0.023. The results suggested that hypertension (diastolic pressure) and hyperglycemia were the factors linked to the heterogeneity among the included studies on both FVC and FEV₁. The Begg's funnel plot and Egger's test both showed no evidence of publication bias. Conclusions: Our results show that FVC and FEV₁ decrease in MS patients, while FEV₁/FVC has no significant difference compared with the control group. It indicates that the patients with MS have restrictive ventilatory functional disturbance. Meta-regression analysis suggests that hypertension (diastolic pressure) and hyperglycemia are the factors linked to the heterogeneity among the included studies on both FVC and FEV₁.

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.

Triglyceride-Glucose Index is a Risk Marker of Incident COPD Events in Women

Purpose

The triglyceride-glucose index (TyG index) is a marker of insulin resistance and metabolic dysfunction and has the advantage of being universally available. Although recent evidence suggests the TyG index has relevance to respiratory health, there have been no prospective studies assessing its value as a biomarker for chronic lung diseases. We aim to assess the TyG index as a potential risk marker for future incident COPD events in the general population.

Patients and Methods

Baseline TyG index was assessed in 28,282 middle-aged men and women without previous history of chronic obstructive pulmonary disease (COPD) from the Malmö Preventive Project (men between 1974 and 1982 and women between 1982 and 1992). All subjects were followed up prospectively, and Cox proportional hazards regression was used to assess incident COPD events according to quartiles of TyG index.

Results

After an average of 31 years of follow-up, TyG index was a strong predictor of future COPD events even after adjusting for potential confounders (Q4 (highest TyG index) HR (95% CI): 1.21 (1.09–1.35) vs Q1 (reference), p-trend <0.001). After stratifying by sex, the results remained statistically significant in women only (Q4 vs Q1 HR 1.72 (1.41–2.09)). Additionally, the risk remained significant in a cohort of life-long never smokers (Q4 vs Q1 HR 1.47 (1.08–2.01)).

Conclusion

A raised TyG index is a novel risk marker of future incident COPD events in women. Insulin resistance as reflected by the TyG index can precede the development of obstructive lung disease and as such may be an easily measurable and useful predictor of COPD in women.

Low Serum Uric Acid Predicts Risk of a Composite Disease Endpoint

Background and objectives: Mortality may increase in hypouricemia as well as inhyperuricemia. We assessed the predictive value of low serum uric acid (SUA) levels on the risk of overall mortality or a composite endpoint of death and nonfatal events. Materials and Methods: In 1013 community-based middle-aged adults, free of uncontrolled diabetes and coronary heart disease at baseline, the association of sex-specific SUA tertiles with defined outcomes was evaluated prospectively by logistic regression, stratified to gender and presence of type-2 diabetes, using recent criteria. Results: Totally, 43 deaths and additional incident nonfatal events in 157 cases were recorded at a median 3.4 years' follow-up. Multivariable linear regression disclosed SUA to be significantly associated among non-diabetic individuals positively with creatinine, triglycerides, and body mass index in women further with fasted glucose. In multivariable-adjusted logistic regression analysis, sex-specifically dichotomized baseline uric acid (<5.1 and <4.1 mg/dL vs. higher values) significantly predicted the non-fatal events in the whole sample (relative risk (RR) 1.51 [95% confidence interval (CI) 1.02; 2.26]), as well as in men, while composite endpoint in the whole sample tended to rise (RR 1.38). Compared with the intermediate one, the top and bottom SUA tertiles combined tended to confer mortality risk (RR 2.40 [95% CI 0.89; 6.51]). Adverse outcomes in diabetic women were predicted by tertiles 2 and 3. Conclusions: Inverse association of SUA with adverse outcomes, especially in men, is consistent with the involvement of uric acid mass in autoimmune activation. The positive association of uric acid with adverse outcomes in diabetic women is likely mediated by concomitant high-density lipoprotein dysfunction.

Association of Metabolic Syndrome and Asthma Status; A Prospective Study from Guilan Province-Iran

INTRODUCTION

Asthma is defined as a chronic inflammatory airway disease. Recent studies have shown the association between metabolic syndrome and deterioration of the lung functions in patients with asthma. The aim of this study was to evaluate the relation between metabolic syndrome and asthma status.

METHODS

In this prospective cross-sectional study, 160 asthmatic patients attending Razi hospital in Guilan province, were divided equally into two groups of 80 patients. The case group was contained asthmatic patient with metabolic syndrome and the control group contain asthmatic patient without metabolic syndrome. Blood pressure, height, weight, waist circumferences, fasting blood glucose and lipid profiles were measured by standard methods. Asthma severity was determined based on clinical symptoms and GINA criteria. To evaluate pulmonary function parameters, spirometry was performed for the patients.

RESULTS

Pulmonary function test including FEF, FVC and FEV1 were significantly lower in the case group compared to control group (P < 0.05). Also, a significant negative correlation was found between waist circumference, cardiovascular risk factors (including diabetes, hypertriglyceridemia, hypertension) with spirometric indices (P < 0.05).

CONCLUSION

Metabolic syndrome causes major declines of pulmonary parameters in asthma patients, thus controlling metabolic syndrome might improve symptoms of asthma.

Effect of Type 2 Diabetes Mellitus and Diabetic Medication on Pulmonary Function

Background:

Type 2 diabetes mellitus (T2DM) is a chronic condition with an impairing effect on multiple organs. Numerous respiratory disorders have been observed in patients with T2DM. However, the effect of T2DM on pulmonary function is inconclusive.

Aims:

In this study, we investigated the effect of T2DM on respiratory function and the correlation of glycemic control, diabetes duration and insulin intake.

Methods:

1500 patients were recruited for this study; 560 having T2DM for at least a year were included in the final data, in addition to 540 healthy volunteers. Forced expiratory volume in one second (FEV1), forced vital capacity (FVC), forced expiratory flow at 25-75% (FEF 25-75%), as well as FEV1/FVC ratio values were measured.

Results:

A two-sample t-test showed that z-scores produced by Al-Qerem et al.’s equations for FEV1, FVC, and FEF 25-75% were significantly lower for the T2DM group than the control group (p < 0.01). FEV1/FVC ratio in the T2DM group was significantly higher (p < 0.01). Multiple linear regression analysis found that glycemic control represented by HbA1c as well as disease duration were negatively associated with the pulmonary function (p < 0.01). However, insulin intake was found to have no significant correlation with pulmonary function.

Conclusion:

T2DM was linked to reduced pulmonary function and was consistent with a restrictive ventilation pattern. HbA1c, as well as disease duration, were found to be independent risk factors for reduced pulmonary function.

Analysis of prevalence and prognosis of type 2 diabetes mellitus in patients with acute exacerbation of COPD

BACKGROUND

For patients with acute exacerbation of COPD (AECOPD), type 2 diabetes mellitus (T2DM) as comorbidity have poor outcomes. However, data on the impact of previously diagnosed and new- diagnosed T2DM in such a patient population is lacking.

METHODS

Inpatients diagnosed with AECOPD in the department of Pulmonary and Critical Care Medicine of The First Hospital of China Medical University during 2011-2017 were enrolled. Data on demography, prevalence of type 2 DM, other comorbidities, hospital stays and laboratory tests (including arterial partial pressure of oxygen [PaO2]) results were recorded. Results were compared with AECOPD patients having previously diagnosed and new-diagnosed type 2 diabetes. Markers associated with development of type 2 DM and the prognosis of AECOPD patients were identified.

RESULTS

Of the 196 patients enrolled in this study, the overall prevalence of T2DM was 26%. The PaO2 in the newly diagnosed T2DM group was considerably lower versus non-diabetic group. The T2DM group had a longer hospital stay and higher troponin level versus the non-diabetic group. AECOPD patients with T2DM were found to be correlated with hypertension. Age, need for assisted ventilation, increased troponin, and elevated fasting blood glucose on admission were risk factors for death in hospitalized AECOPD patients.

CONCLUSIONS

AECOPD patients had a higher prevalence of T2DM than the general population; T2DM comorbidity caused lower PaO2, longer hospital stays, and increased troponin. Poor blood glucose control may increase the risk of death in AECOPD patients.

Association between restrictive pulmonary disease and type 2 diabetes in Koreans: A cross-sectional study

BACKGROUND

Diabetes is a progressive disease that increases glucose levels in the blood. While studies have shown that patients with pulmonary disease (both obstructive and restrictive pulmonary disease) have a higher prevalence of type 2 diabetes mellitus (T2DM), there have been more studies on restrictive patterns than chronic obstructive pulmonary disease.

AIM

To assess whether restrictive and obstructive pulmonary diseases are associated with T2DM in Koreans.

METHODS

For our analysis, we used data from the Korea National Health and Nutrition Examination Survey. A total of 2830 subjects were included in this study. Spirometry results were categorized into three patterns: Normal, restrictive pulmonary disease (RPD), and obstructive pulmonary disease (OPD).

RESULTS

The factors used as diabetic indicators (i.e. homeostatic model assessment of insulin resistance, homeostatic model assessment of beta-cell function, glycated hemoglobin, and fasting insulin) were among the highest in RPD but not in OPD. Based on multivariate logistic regression analysis, subjects with RPD were found with an increased odds ratio [OR: 1.907, 95% confidence interval (CI): 1.110-3.277] for T2DM compared with subjects with normal pulmonary function, whereas in patients with OPD, the OR had not increased. Model 4, which adjusted for the variables that could affect diabetes and pulmonary disease, showed a significant increase in the T2DM OR to RPD (OR: 2.025, 95%CI: 1.264-3.244). On the other hand, no statistically significant difference was shown in OPD (OR: 0.982, 95%CI: 0.634-1.519).

CONCLUSION

RPD, not OPD, is highly associated with T2DM regardless of the risk factors of various T2DMs that can be confounds.

The Association between Pulmonary Functions and Incident Diabetes: Longitudinal Analysis from the Ansung Cohort in Korea

BACKGROUND

We sought to explore whether reduced pulmonary function is an independent risk factor for incident diabetes in Koreans.

METHODS

We conducted a prospective cohort study of pulmonary function as a risk factor for incident diabetes using 10-year follow-up data from 3,864 middle-aged adults from the Ansung cohort study in Korea. The incidence of diabetes was assessed using both oral glucose tolerance tests and glycosylated hemoglobin levels.

RESULTS

During 37,118 person-years of follow-up, 583 participants developed diabetes (incidence rate: 15.7 per 1,000 person-years). The mean follow-up period was 8.0±3.7 years. Forced vital capacity (FVC; % predicted) and forced expiratory volume in 1 second (FEV1; % predicted) were significantly correlated with incident diabetes in a graded manner after adjustment for sex, age, smoking, exercise, and metabolic parameters. The adjusted hazard ratio (HR) and confidence interval (CI) for diabetes were 1.408 (1.106 to 1.792) and 1.469 (1.137 to 1.897) in the first quartiles of FVC and FEV1, respectively, when compared with the highest quartile. Furthermore, the FVC of the lowest first and second quartiles showed a significantly higher 10-year panel homeostasis model assessment of insulin resistance index, with differences of 0.095 (95% CI, 0.010 to 0.018; P=0.028) and 0.127 (95% CI, 0.044 to 0.210; P=0.003), respectively, when compared to the highest quartiles.

CONCLUSION

FVC and FEV1 are independent risk factors for developing diabetes in Koreans. Pulmonary factors are possible risk factors for insulin resistance and diabetes.

Waist to Height Ratio and Metabolic Syndrome as lung dysfunction predictors

Metabolic Syndrome (MetS) has been related to pulmonary diseases but its relationship with lung age has not been sufficiently studied. In addition, anthropometric variables have been associated with pulmonary dysfunction, highlighting the waist-to-height ratio (WHtR). The aim was to evaluate the relationship between MetS and: lung age, anthropometric variables and the alteration of lung function. A cross-sectional study was carried out in 1901 workers, evaluating lung function through lung age (Morris & Temple equation) and spirometric values. The diagnosis of MetS was based on the harmonized criteria. We measured anthropometric variables (WHtR, waist circumference, body mass index, waist to hip ratio), blood pressure and biochemical variables (glucose, cholesterol total, HDL, triglycerides). Workers suffering from MetS showed an accelerated lung aging (59.4 ± 18.7 years vs 49 ± 18.4 years). The WHtR ≥ 0.55 was significantly related to an increase in lung age (β = 6.393, p < 0.001). In addition, a significant linear trend was found between clinical categories of WHtR and lung dysfunction, restrictive and mixed pattern. MetS caused an accelerated lung aging and favored the presence of restrictive lung impairment. In addition, WHtR ≥ 0.55 has been shown as the best predictor for pulmonary health.

Do Benefits Outweigh Risks for Corticosteroid Therapy in Acute Exacerbation of Chronic Obstructive Pulmonary Disease in People with Diabetes Mellitus?

Chronic obstructive pulmonary disease (COPD) and diabetes mellitus (DM) are chronic health conditions with significant impacts on quality and extent of life. People with COPD and DM appear to have worse outcomes in each of the comorbid conditions. Treatment with corticosteroids in acute exacerbation of COPD (AECOPD) has been shown to reduce treatment failure and exacerbation relapse, and to shorten length of hospital stay, but not to affect the inexorable gradual worsening of lung function. Treatment with corticosteroids can lead to a wide spectrum of side effects and complications, including worsening hyperglycemia and deterioration of diabetes control in those with pre-existing DM. The relationship between COPD and DM is rather complex and accumulating evidence indicates a distinct phenotype of the comorbid state. Several randomized controlled trials on corticosteroid treatment in AECOPD excluded people with DM or did not report on outcomes in this subgroup. As such, the perceived benefits of corticosteroids in AECOPD in people with DM have not been validated. In people with COPD and DM, the detrimental side effects of corticosteroids are guaranteed, while the benefits are not confirmed and only presumed based on extrapolation from the general COPD population. Therefore, the potential for harm when prescribing corticosteroids for AECOPD in people with DM cannot be excluded.

Lung function measurements in the prediabetes stage: data from the ILERVAS Project

AIMS

Patients with type 2 diabetes have been considered a susceptible group for pulmonary dysfunction. Our aim was to assess pulmonary function on the prediabetes stage.

METHODS

Pulmonary function was assessed in 4,459 non-diabetic subjects, aged between 45 and 70 years, without cardiovascular disease or chronic pulmonary obstructive disease from the ongoing study ILERVAS. A "restrictive spirometric pattern", an "abnormal FEV1" and an "obstructive ventilatory defect" were assessed. Prediabetes was defined by glycosylated hemoglobin (HbA1c) between 5.7 and 6.4% according to the American Diabetes Association criteria.

RESULTS

Population was composed of 52.1% women, aged 57 [53;63] years, a BMI of 28.6 [25.8;31.8] kg/m², and with a prevalence of prediabetes of 29.9% (n = 1392). Subjects with prediabetes had lower forced vital capacity (FVC: 93 [82;105] vs. 96 [84;106], p < 0.001) and lower forced expired volume in the first second (FEV1: 94 [82;107] vs. 96 [84;108], p = 0.011), as well as a higher percentage of the restrictive spirometric pattern (16.5% vs. 13.6%, p = 0.015) and FEV1 < 80% (20.3% vs. 17.2%, p = 0.017) compared to non-prediabetes group. In the prediabetes group, HbA1c was negatively correlated with both pulmonary parameters (FVC: r = - 0.113, p < 0.001; FEV1: r = - 0.079, p = 0.003). The multivariable logistic regression model in the whole population showed that there was a significant and independent association between HbA1c with both restrictive spirometric pattern [OR = 1.42 (1.10-1.83), p = 0.008] and FEV1 < 80% [OR = 1.50 (1.19-1.90), p = 0.001].

CONCLUSIONS

The deleterious effect of type 2 diabetes on pulmonary function appears to be initiated in prediabetes, and it is related to metabolic control. TRIAL REGISTRATION CLINICALTRIALS.GOV: NCT03228459.

Interactive effects of adiposity and insulin resistance on the impaired lung function in asthmatic adults: cross-sectional analysis of NHANES data

BACKGROUND

Obesity is considered a risk factor for both asthma and insulin resistance in adults. Insulin resistance (IR) also influences pulmonary function in the non-obese population.

AIM

To investigate the modifying effect of insulin resistance on the predictive role of anthropometric measures in the estimation of impaired lung function among asthmatic adults.

SUBJECTS AND METHODS

A cross-sectional study of 1276 adults extracted from the NHANES 2009-2012 database was performed. Adjusted multiple linear regression was conducted to analyse the contributory role of obesity and IR in predicting lung function among asthmatic adults.

RESULTS

BMI, waist circumference (WC) and waist-to-height ratio (WHtR) showed significantly negative correlations with FVC (r=-0.24, -0.18, -0.39, respectively; p < 0.001), FEV1(r=-0.24, -0.21, -0.40, respectively; p < 0.001) and FEF 25-75% (r=-0.15, -0.18, -0.27, respectively; p < 0.001). Even after adjustment for the covariates (age, gender, smoking history and standing height), BMI and HOMA-IR had significant relationships with FVC (β= -10.3; p < 0.01 and β= -16.0; p < 0.05) and FEV1 (β= -8.7; p < 0.01 and β= -11.7; p < 0.05). BMI could significantly predict the decreased FVC (β= -13.7; p < 0.01) and FEV1 (β= -10.7; p < 0.01) only in the insulin resistant asthmatics.

CONCLUSION

WHtR and IR predict impaired lung function in overweight/obese asthmatic adults independently. IR also modifies the association between excessive adiposity and respiratory function in asthmatic adults.

Diet and Metabolism in the Evolution of Asthma and Obesity

Obesity is a major risk factor for asthma. This association appears related to altered dietary composition and metabolic factors that can directly affect airway reactivity and airway inflammation. This article discusses how specific changes in the western diet and metabolic changes associated with the obese state affect inflammation and airway reactivity and reviews evidence that interventions targeting weight, dietary components, lifestyle, and metabolism might improve outcomes in asthma.

The association between the metabolic syndrome and metabolic syndrome score and pulmonary function in non-smoking adults

OBJECTIVE

This study assessed the association of metabolic syndrome and metabolic syndrome score with the predicted forced vital capacity and predicted forced expiratory volume in 1 s (predicted forced expiratory volume in 1 s) values in Korean non-smoking adults.

METHODS

We analysed data obtained from 6684 adults during the 2013-2015 Korean National Health and Nutrition Examination Survey.

RESULTS

After adjustment for related variables, metabolic syndrome ( p < 0.001) and metabolic syndrome score ( p < 0.001) were found to be inversely associated with the predicted forced vital capacity and forced expiratory volume in 1 s values. The odds ratios of restrictive pulmonary disease (the predicted forced vital capacity < 80.0% with forced expiratory volume in 1 s/FVC ⩾ 70.0%) by metabolic syndrome score with metabolic syndrome score 0 as a reference group showed no significance for metabolic syndrome score 1 [1.061 (95% confidence interval, 0.755-1.490)] and metabolic syndrome score 2 [1.247 (95% confidence interval, 0.890-1.747)], but showed significant for metabolic syndrome score 3 [1.433 (95% confidence interval, 1.010-2.033)] and metabolic syndrome score ⩾ 4 [1.760 (95% confidence interval, 1.216-2.550)]. In addition, the odds ratio of restrictive pulmonary disease of the metabolic syndrome [1.360 (95% confidence interval, 1.118-1.655)] was significantly higher than those of non-metabolic syndrome.

CONCLUSION

Metabolic syndrome and metabolic syndrome score were inversely associated with the predicted forced vital capacity and forced expiratory volume in 1 s values in Korean non-smoking adults. In addition, metabolic syndrome and metabolic syndrome score were positively associated with the restrictive pulmonary disease.

The longitudinal association between changes in lung function and changes in abdominal visceral obesity in Korean non-smokers

Obesity, particularly abdominal obesity, might be related to decreased lung function. We aimed to investigate whether obesity indices are associated with forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) in asymptomatic non-smokers through a longitudinal cohort study. The clinical records of 1,145 subjects (428 males, mean age 52.3 years) who underwent a comprehensive health evaluation, including spirometry and abdominal fat computed tomography, at least twice between 2007 and 2014 were retrospectively reviewed and analysed. The mean follow-up period was 1,105 days (over 3.0 years). The baseline total adipose tissue (TAT) and visceral adipose tissue (VAT) were inversely associated with both FEV1 and FVC (P < 0.05). The longitudinal study found that increasing TAT and VAT were significantly related to decreasing FEV1 and FVC, whereas decreasing TAT and VAT were related to increasing FEV1 and FVC in both males and females (P < 0.05). The strength and consistency of these associations were clearer in males than in females. However, no significant relationship was found between changes in subcutaneous adipose tissue and changes in lung function. In Korean non-smokers, longitudinal changes in abdominal visceral fat were found to be inversely related to changes in lung function over a mean period of three years. These results suggest that decreasing abdominal visceral obesity could increase lung function despite ageing.

Pulmonary Function and Sleep Breathing: Two New Targets for Type 2 Diabetes Care

Population-based studies showing the negative impact of type 2 diabetes (T2D) on lung function are overviewed. Among the well-recognized pathophysiological mechanisms, the metabolic pathways related to insulin resistance (IR), low-grade chronic inflammation, leptin resistance, microvascular damage, and autonomic neuropathy are emphasized. Histopathological changes are exposed, and findings reported from experimental models are clearly differentiated from those described in humans. The accelerated decline in pulmonary function that appears in patients with cystic fibrosis (CF) with related abnormalities of glucose tolerance and diabetes is considered as an example to further investigate the relationship between T2D and the lung. Furthermore, a possible causal link between antihyperglycemic therapies and pulmonary function is examined. T2D similarly affects breathing during sleep, becoming an independent risk factor for higher rates of sleep apnea, leading to nocturnal hypoxemia and daytime sleepiness. Therefore, the impact of T2D on sleep breathing and its influence on sleep architecture is analyzed. Finally, the effect of improving some pathophysiological mechanisms, primarily IR and inflammation, as well as the optimization of blood glucose control on sleep breathing is evaluated. In summary, the lung should be considered by those providing care for people with diabetes and raise the central issue of whether the normalization of glucose levels can improve pulmonary function and ameliorate sleep-disordered breathing. Therefore, patients with T2D should be considered a vulnerable group for pulmonary dysfunction. However, further research aimed at elucidating how to screen for the lung impairment in the population with diabetes in a cost-effective manner is needed.

Glycated hemoglobin A1c-based adjusted glycemic variables in patients with diabetes presenting with acute exacerbation of chronic obstructive pulmonary disease

Acute hyperglycemia is a common finding in patients presenting to emergency departments (EDs) with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Several studies have argued against the association between hyperglycemia at admission and adverse outcomes in patients with diabetes and an acute illness. Recent studies have shown that glucose-related variables (eg, glycemic gaps and stress hyperglycemia ratios) that are adjusted for glycated hemoglobin levels can indicate the severity of a variety of diseases. The objective of this study was to assess whether these hemoglobin A1c (HbA1c)-based adjusted average glycemic variables were associated with unfavorable outcomes in patients admitted to a hospital with AECOPD. We found that 1) pulmonary infection is a major risk factor for AECOPD; 2) a higher glycemic gap and modified stress hyperglycemia ratio were associated with the development of acute respiratory failure (ARF) in patients with diabetes admitted to an ED because of AECOPD; and 3) the glycemic gap and modified stress hyperglycemia ratio had superior discriminative power over acute hyperglycemia and HbA1c for predicting the development of ARF, although the HbA1c-adjusted glycemic variables alone were not independent risk factors for ARF.

Decline in lung function rather than baseline lung function is associated with the development of metabolic syndrome: A six-year longitudinal study

This study was conducted to investigate whether baseline lung function or change in lung function is associated with the development of metabolic syndrome (MS) in Koreans. We analyzed clinical and laboratory data from 3,768 Koreans aged 40–60 years who underwent medical check-ups over a six-year period between 2006 and 2012. We calculated the percent change in forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV₁) over the study period. We tested for an association between baseline lung function or lung function change during the follow-up period and the development of MS. The 533 subjects (14.1%) developed MS after the six-year follow-up. The baseline FVC and FEV₁ were not different between the subjects who developed MS after six years and the subject without MS after six years. The percent change in FVC over six years in subjects who developed MS after six years was higher than that in subjects who did not develop MS (-5.75 [-10.19 –-1.17], -3.29 [-7.69–1.09], respectively, P = 0.001). The percent change in FVC over six years was associated with MS development after adjusting for age, sex, body mass index (BMI), glucose, HDL, triglyceride, waist circumferences (WC), and systolic blood pressure. However, these association was not significant after adjusting for change of BMI and change of WC over six years (P = 0.306). The greater change in vital capacity over six years of follow-up was associated with MS development, predominantly due to obesity and abdominal obesity. The prospective study is needed to determine the relationship between lung function decline and MS.

The relationship between serum fatty-acid binding protein 4 level and lung function in Korean subjects with normal ventilatory function

Background

The aim of this study was to assess the association of lung function with serum fatty-acid binding protein 4 (FABP4) in apparently healthy Korean adults.

Methods

In 495 participants in a health screening program, Force Exploratory Volume (FEV) 1 and Forced Vital Capacity (FVC) were assessed with standard spirometry. Subjects with obstructive (n = 19) and restrictive (n = 45) lung function were excluded from the analysis. Serum FABP4 level was measured by enzyme-linked immunosorbent assay and transformed into Ln(FABP4). 431 subjects with normal ventilator function (72.4 % men, mean age 41 years) were included in the final analysis.

Results

Mean Ln(FABP4) significantly decreased in subjects from 1^st quartile to 4^th quartile of FVC (p = 0.008). Ln(FABP4) did not show significant differences across the quartile groups of FEV1. The odds ratio (OR) of being in the lowest quartile of FVC was 2.704 in subject with 3^rd tertile of Ln(FABP4) after full adjustment for confounding variables {95 % confidence interval (CI) 1.397 ~ 5.357}. OR of being in the lowest quartile of FEV1 was 1.822 (95 % CI 1.021 ~ 3.298) in subjects with 3^rd tertile of Ln(FABP4) after adjustment of age and sex, which was attenuated after full adjustment for confounding variables.

Conclusion

Increased FABP4 level showed increased risk for reduced lung function in subjects with normal ventilatory function.

Electronic supplementary material

The online version of this article (doi:10.1186/s12890-016-0190-8) contains supplementary material, which is available to authorized users.

The association of reduced lung function with blood pressure variability in African Americans: data from the Jackson Heart Study

Background

African Americans (AAs) have lower lung function, higher blood pressure variability (BPV) and increased risk for hypertension and cardiovascular disease (CVD) compared with whites. The mechanism through which reduced lung-function is associated with increased CVD risk is unclear.

Methods

We evaluated the association between percent predicted lung-function and 24-hour BPV in 1008 AAs enrolled in the Jackson Heart Study who underwent ambulatory blood pressure (BP) monitoring. Lung-function was assessed as forced expiratory volume in one second (FEV1), forced vital capacity (FVC) and the ratio of FEV1-to-FVC during a pulmonary function test using a dry rolling sealed spirometer and grouped into gender-specific quartiles. The pairwise associations of these three lung-function measures with two measures of 24-hour BPV, (1) day-night standard deviation (SD_dn) and (2) average real variability (ARV) were examined for systolic BP (SBP) and, separately, diastolic BP (DBP).

Results

SD_dn of SBP was not associated with FEV1 (mean ± standard deviation from lowest-to-highest quartile: 9.5 ± 2.5, 9.4 ± 2.4, 9.1 ± 2.3, 9.3 ± 2.6; p-trend = 0.111). After age and sex adjustment, the difference in SD_dn of SBP was 0.0 (95 % CI −0.4,0.4), −0.4 (95 % CI −0.8,0.1) and −0.3 (95 % CI −0.7,0.1) in the three progressively higher versus lowest quartiles of FEV1 (p-trend = 0.041). Differences in SD_dn of SBP across FEV1 quartiles were not statistically significant after further multivariable adjustment. After multivariable adjustment, no association was present between FEV1 and ARV of SBP or SD_dn and ARV of DBP or when evaluating the association of FVC and FEV1-to-FVC with 24-hour BPV.

Conclusion

Lung-function was not associated with increased 24-hour BPV.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-015-0182-2) contains supplementary material, which is available to authorized users.

The Vital Capacity Is Vital: Epidemiology and Clinical Significance of the Restrictive Spirometry Pattern

Epidemiologic research has revealed a substantial portion of the general population with abnormal spirometry results that are characterized by decreased FEV1 and FVC but a preserved FEV1/FVC ratio. This restrictive spirometry pattern (RSP) is inconsistently defined in the literature and not well addressed by current guidelines; there is an accumulating body of evidence, however, that RSP is prevalent to a similar degree as airflow obstruction. Genetic and other risk factors for RSP, such as inhalational injuries and early life exposures, continue to be actively described. Although it seems that RSP is closely associated with the metabolic syndrome, diabetes, and systemic inflammation, it is not a simple marker of obesity. RSP is associated with adverse cardiovascular outcomes, as well as mortality, and it may be an underappreciated cause of functional impairments and respiratory symptoms. Improvement in outcomes in this population will require that clinicians have an appreciation for the significance of this spirometry pattern; additional research into the clinical and radiologic phenotype of these subjects is also needed. This article provides an overview of the recent developments in our understanding of this prevalent and highly morbid spirometry pattern.

The Relationship of Metabolic Syndrome with Stress, Coronary Heart Disease and Pulmonary Function--An Occupational Cohort-Based Study

BACKGROUND AND AIMS

Higher levels of stress impact the prevalence of metabolic syndrome (MetS) and coronary heart disease. The association between MetS, impaired pulmonary function and low level of physical activity is still pending assessment in the subjects exposed to stress. The study aimed to examine whether higher levels of stress might be related to MetS and the plaque presence, as well as whether MetS might affect pulmonary function.

DESIGN AND METHODS

The study embraced 235 police officers (mean age 40.97 years) from the south of Poland. The anthropometrics and biochemical variables were measured; MetS was diagnosed using the International Diabetes Federation criteria. Computed tomography coronary angiography of coronary arteries, exercise ECG, measurements of brachial flow-mediated dilation, and carotid artery intima-media thickness were completed. In order to measure the self-perception of stress, 10-item Perceived Stress Scale (PSS-10) was applied. Pulmonary function and physical activity levels were also addressed. Multivariate logistic regression analyses were applied to determine the relationships between: 1/ incidence of coronary plaque and MetS per se, MetS components and the number of classical cardiovascular risk factors, 2/ perceived stress and MetS, 3/ MetS and pulmonary function parameters.

RESULTS

Coronary artery atherosclerosis was less associated with MetS (OR = 2.62, 95%CI 1.24-5.52; p = 0.011) than with a co-existence of classical cardiovascular risk factors (OR = 5.67, 95% CI 1.07-29.85, p = 0.03; for 3 risk factors and OR = 9.05; 95% CI 1.24-66.23, p = 0.02; for 6 risk factors, respectively). Perceived stress increased MetS prevalence (OR = 1.07, 95% CI 1.03-1.13; p = 0.03), and impacted coronary plaque prevalence (OR = 1.05, 95% CI 1.001-1.10; p = 0.04). Leisure-time physical activity reduced the chances of developing MetS (OR = 0.98 95% CI 0.96-0.99; p = 0.02). MetS subjects had significantly lower values of certain pulmonary function parameters.

CONCLUSIONS

Exposure to job-specific stress among police officers increased the prevalence of MetS and impacted coronary plaque presence. MetS subjects had worse pulmonary function parameters. Early-stage, comprehensive therapeutic intervention may reduce overall risk of cardiovascular events and prevent pulmonary function impairment in this specific occupational population.

Insulin resistance, metabolic syndrome, and lung function in US adolescents with and without asthma

BACKGROUND

Obesity increases both the risk of asthma and asthma severity and is a well-known risk factor for insulin resistance and the metabolic syndrome (MS) in children and adolescents.

OBJECTIVE

We aimed to examine the association among obesity, insulin sensitivity, MS, and lung function in US adolescents with and without asthma.

METHODS

We performed a cross-sectional study of 1429 adolescents aged 12 to 17 years in the 2007-2010 National Health and Nutrition Examination Survey. Adjusted regression was used to assess the relationships among obesity, insulin sensitivity/resistance, MS, and lung function in children with and without asthma.

RESULTS

Insulin resistance was negatively associated with FEV1 and forced vital capacity (FVC) in adolescents with and without asthma, whereas MS was associated with lower FEV1/FVC ratios, with a more pronounced decrease found among asthmatic patients; these associations were driven by overweight/obese adolescents. Higher body mass index was associated with a decrease in FEV1/FVC ratios among adolescents with insulin resistance. Compared with healthy participants, adolescents with MS had an approximately 2% decrease in FEV1/FVC ratios, adolescents with asthma had an approximately 6% decrease, and those with MS and asthma had approximately 10% decreased FEV1/FVC ratios (P < .05).

CONCLUSION

Insulin resistance and MS are associated with worsened lung function in overweight/obese adolescents. Asthma and MS synergistically decrease lung function, as do obesity and insulin resistance. These factors might contribute to the pathogenesis of asthma severity in obese patients and warrant further investigation.

Chronic obstructive pulmonary disease and diabetes mellitus: a systematic review of the literature

The objective of this systematic review was to discuss our current understanding of the complex relationship between chronic obstructive pulmonary disease (COPD) and type-2 diabetes mellitus (T2DM). We performed a systematic search of the literature related to both COPD and diabetes using PubMed. Relevant data connecting both diseases were compiled and discussed. Recent evidence suggests that diabetes can worsen the progression and prognosis of COPD; this may result from the direct effects of hyperglycemia on lung physiology, inflammation or susceptibility to bacterial infection. Conversely, it has also been suggested that COPD increases the risk of developing T2DM as a consequence of inflammatory processes and/or therapeutic side effects related to the use of high-dose corticosteroids. In conclusion, although there is evidence to support a connection between COPD and diabetes, additional research is needed to better understand these relationships and their possible implications.

Lung function and metabolic syndrome: Findings of National Health and Nutrition Examination Survey 2007–2010

BACKGROUND

Considerable uncertainty remains about obstructive lung function( OLF) in adults with metabolic syndrome (MetS). The aim of the present study was to examine pulmonary function status in adults with and without MetS.

METHODS

We used data from 3109 participants aged ≥20 years of the National Health and Nutrition Examination Survey 2007-2010. Subjects'MetS status was established on the basis of the 2009 harmonizing definition. Participants received spirometry.

RESULTS

After age adjustment, 79.3% (SE 1.1) of participants with MetS had normal lung function, 8.7% (0.9) had restrictive lung function (RLF), 7.1% (0.8) had mild OLF, and 4.8% (0.6) had moderate OLF or worse. Among participants without MetS, these estimates were 78.7% (1.2), 3.9% (0.6), 10.9%(1.1), and 6.4% (0.8), respectively. After multiple adjustment, participants with MetS were more likely to have RLF (adjusted prevalence ratio [aPR] 2.20; 95% confidence interval [CI] 1.67, 2.90) and less likely to have any OLF (aPR 0.73; 95% CI 0.62, 0.86) than those without MetS. Furthermore, participants with MetS had lower mean levels of forced expiratory volume in one second (FEV1), FEV1 % predicted, forced vital capacity (FVC), and FVC % predicted, but a higher FEV1/FVC ratio than participants without MetS. Mean levels of FEV1, FEV1 % predicted, FVC, and FVC % predicted declined significantly, but not the FEV1/FVC ratio, as the number of components increased.

CONCLUSIONS

Compared with adults without MetS, spirometry is more likely to show a restrictive pattern and less likely to show an obstructive pattern among adults with MetS.

Renal "hyperfiltrators" are at elevated risk of death and chronic diseases

Background

The definition of glomerular hyperfiltration has not been agreed upon and the pathophysiological mechanisms have not been well explored. Low serum creatinine concentrations may be associated with increased risk of coronary heart disease (CHD) or cardiopulmonary events the impact of which needs further study.

Methods

Consecutive applicants to a cardiovascular hospital free of moderate/severe chronic kidney disease (age 55.6 ± 8.2 years) were grouped into those without (“healthy”, n = 469) and with CHD (320 stable and acute coronary syndrome cases) at baseline and into sex-specific quartiles of CKD-EPI equation-estimated glomerular filtration rate (eGFR). New or recurrent cardiovascular (myocardial infarction, stroke, heart failure [HF]) events, obstructive pulmonary disease (COPD) and death were determined during 3-years’ follow-up.

Results

Among 25 deaths and 75 cardiopulmonary events, HF was the leading nonfatal event. Age, serum uric acid and left ventricular ejection fraction proved the best independent inverse covariates of eGFR in the “healthy” sample. The highest eGFR quartile (“hyperfiltrators”), exhibiting significantly lower serum LDL-cholesterol levels, significantly predicted the combined outcome (at a RR of 6) in “healthy” subjects, after adjustment for sex, age, body mass index, smoking status and presence of hypertension. This finding was paralleled by the highest eGFR quartile calculated also by the MDRD equation, replicating this also in the CHD group.

Conclusion

Renal “hyperfiltrators” represent individuals with autoimmune activation (involving serum creatinine, partly escaping assay), are misclassified into optimal renal function and actually are at significantly higher risk of death, HF or cardiopulmonary events. Low serum creatinine levels may represent a clue to the existence of autoimmune activation.

Restrictive pulmonary deficit is associated with inflammation in sub-optimally controlled obese diabetics

Caribbean data linking inflammation, pulmonary dysfunction and diabetes is unavailable. Spirometry, acanthosis nigricans, hs-CRP were assessed in 109 type 2 diabetics (43% males) mean age=55.6 years, BMI=29.29 kg/m(2), waist circumference=103.86 cm. Residual FEV1/FVC increased with age (P=0.005), BMI (P=0.011) and waist circumference (P=0.003). Residual FVC related inversely to hs-CRP (-0.178), P<0.06) systolic (-0.028, P<0.031), diastolic (-0.247, P<0.010) pressure and weight (-0.25, P<0.009). Residual FEV1 related inversely to diastolic pressure (-0.219, P<0.023), hs-CRP (-0.234, P<0.015), acanthosis nigricans (-0.029, P<0.029). HbA1C and residual FEV1 predict high hs-CRP (P=0.011, P=0.046). Low FVC with inflammation presents in poorly controlled obese diabetics.

Elevated cardiovascular risk among adults with obstructive and restrictive airway functioning in the United States: a cross-sectional study of the National Health and Nutrition Examination Survey from 2007-2010

BACKGROUND

Reasons for the excess risk for cardiovascular disease among people with chronic obstructive pulmonary disease remain unclear. Our objective was to examine the cardiovascular risk profile for adults with obstructive and restrictive impairments of lung functioning in a representative sample of adults from the United States.

METHODS

We used data from adults aged 20-79 years who participated in the National Health and Nutrition Examination Survey from 2007 to 2010 and had a pulmonary function test. The severity of obstructive impairment was defined by adapting the Global Initiative for Chronic Obstructive Lung Disease criteria.

RESULTS

Among 7249 participants, 80.9% had a normal pulmonary function test, 5.7% had a restrictive impairment, 7.9% had mild obstructive impairment, and 5.5% had moderate or severe/very severe obstructive impairment. Participants with obstructive impairment had high rates of smoking and increased serum concentrations of cotinine. Compared to participants with normal pulmonary functioning, participants with at least moderate obstructive impairment had elevated concentrations of C-reactive protein but lower concentrations of total cholesterol and non-high-density lipoprotein cholesterol. Among participants aged 50-74 years, participants with at least a moderate obstructive impairment or a restrictive impairment had an elevated predicted 10-year risk for cardiovascular disease.

CONCLUSIONS

The high rates of smoking among adults with impaired pulmonary functioning, particularly those with obstructive impairment, point to a need for aggressive efforts to promote smoking cessation in these adults. In addition, adults with restrictive impairment may require increased attention to and fine-tuning of their cardiovascular risk profile.

Chronic obstructive pulmonary disease and glucose metabolism: a bitter sweet symphony

Chronic obstructive pulmonary disease, metabolic syndrome and diabetes mellitus are common and underdiagnosed medical conditions. It was predicted that chronic obstructive pulmonary disease will be the third leading cause of death worldwide by 2020. The healthcare burden of this disease is even greater if we consider the significant impact of chronic obstructive pulmonary disease on the cardiovascular morbidity and mortality. Chronic obstructive pulmonary disease may be considered as a novel risk factor for new onset type 2 diabetes mellitus via multiple pathophysiological alterations such as: inflammation and oxidative stress, insulin resistance, weight gain and alterations in metabolism of adipokines. On the other hand, diabetes may act as an independent factor, negatively affecting pulmonary structure and function. Diabetes is associated with an increased risk of pulmonary infections, disease exacerbations and worsened COPD outcomes. On the top of that, coexistent OSA may increase the risk for type 2 DM in some individuals. The current scientific data necessitate a greater outlook on chronic obstructive pulmonary disease and chronic obstructive pulmonary disease may be viewed as a risk factor for the new onset type 2 diabetes mellitus. Conversely, both types of diabetes mellitus should be viewed as strong contributing factors for the development of obstructive lung disease. Such approach can potentially improve the outcomes and medical control for both conditions, and, thus, decrease the healthcare burden of these major medical problems.

Reduced lung function is independently associated with increased risk of type 2 diabetes in Korean men

Background

Reduced lung function is associated with incident insulin resistance and diabetes. The aim of this study was to assess the relationship between lung function and incident type 2 diabetes in Korean men.

Methods

This study included 9,220 men (mean age: 41.4 years) without type 2 diabetes at baseline who were followed for five years. Subjects were divided into four groups according to baseline forced vital capacity (FVC) (% predicted) and forced expiratory volume in one second (FEV₁) (% predicted) quartiles. The incidence of type 2 diabetes at follow-up was compared according to FVC and FEV₁ quartiles.

Results

The overall incidence of type 2 diabetes was 2.2%. Reduced lung function was significantly associated with the incidence of type 2 diabetes after adjusting for age, BMI, education, smoking, exercise, alcohol, and HOMA-IR. Both FVC and FEV₁ were negatively associated with type 2 diabetes (P < 0.05). In non-obese subjects with BMI < 25, the lowest quartile of FVC and FEV₁ had a significantly higher odds ratio for type 2 diabetes compared with the highest quartile after adjusting for age and BMI (2.15 [95% CI 1.02-4.57] and 2.19 [95% CI 1.09-4.42]).

Conclusions

Reduced lung function is independently associated with the incidence of type 2 diabetes in Korean men.

Metabolic syndrome biomarkers predict lung function impairment: a nested case-control study

RATIONALE

Cross-sectional studies demonstrate an association between metabolic syndrome and impaired lung function.

OBJECTIVES

To define if metabolic syndrome biomarkers are risk factors for loss of lung function after irritant exposure.

METHODS

A nested case-control study of Fire Department of New York personnel with normal pre-September 11th FEV(1) and who presented for subspecialty pulmonary evaluation before March 10, 2008. We correlated metabolic syndrome biomarkers obtained within 6 months of World Trade Center dust exposure with subsequent FEV(1). FEV(1) at subspecialty pulmonary evaluation within 6.5 years defined disease status; cases had FEV(1) less than lower limit of normal, whereas control subjects had FEV(1) greater than or equal to lower limit of normal.

MEASUREMENTS AND MAIN RESULTS

Clinical data and serum sampled at the first monitoring examination within 6 months of September 11, 2001, assessed body mass index, heart rate, serum glucose, triglycerides and high-density lipoprotein (HDL), leptin, pancreatic polypeptide, and amylin. Cases and control subjects had significant differences in HDL less than 40 mg/dl with triglycerides greater than or equal to 150 mg/dl, heart rate greater than or equal to 66 bpm, and leptin greater than or equal to 10,300 pg/ml. Each increased the odds of abnormal FEV(1) at pulmonary evaluation by more than twofold, whereas amylin greater than or equal to 116 pg/ml decreased the odds by 84%, in a multibiomarker model adjusting for age, race, body mass index, and World Trade Center arrival time. This model had a sensitivity of 41%, a specificity of 86%, and a receiver operating characteristic area under the curve of 0.77.

CONCLUSIONS

Abnormal triglycerides and HDL and elevated heart rate and leptin are independent risk factors of greater susceptibility to lung function impairment after September 11, 2001, whereas elevated amylin is protective. Metabolic biomarkers are predictors of lung disease, and may be useful for assessing risk of impaired lung function in response to particulate inhalation.

Relationships of decreased lung function with metabolic syndrome and obstructive sleep apnea in Japanese males

OBJECTIVE

Decreased lung function as assessed by forced vital capacity (FVC) and forced expiratory volume in one second (FEV(1)) is shown to be associated with cardiovascular morbidity and mortality. Although the underlying mechanisms for this association remain unknown, metabolic syndrome and obstructive sleep apnea (OSA) may have a role. We analyzed the relationships between metabolic syndrome and OSA in a cross-sectional health survey of middle-aged male employees.

METHODS

In this secondary analysis, we re-analyzed the relationships of lung function determined by spirometry with metabolic syndrome and OSA based on the respiratory disturbance index (RDI) with a type 3 portable monitor.

RESULTS

We analyzed 273 subjects. Independent of age, body mass index (BMI) and smoking, quartiles for lower FVC and FEV(1) were associated with a higher risk of metabolic syndrome compared with quartiles for the highest FVC and FEV(1), respectively. A similar trend was observed regarding the risk associated with waist circumference, and in FVC cases, dyslipidemia. The risk of hyperglycemia was significantly higher in quartiles for the second lowest FVC and FEV(1) than in quartiles for the highest FVC and FEV(1), respectively. A significant trend for an increase in RDI was observed in accordance with quartiles for lower FVC, but not FEV(1).

CONCLUSION

There was a significant relationship between lung function impairment and metabolic syndrome through mainly abdominal obesity, partially through hyperglycemia, and also through dyslipidemia, but only with respect to restrictive lung function. Restrictive lung function was also related to OSA. This epidemiologic evidence may indicate underlying mechanisms between decreased lung function and cardiovascular risk.

Impact of visceral adiposity measured by abdominal computed tomography on pulmonary function

Although an inverse relationship between abdominal adiposity and pulmonary function has been suggested, direct measurement of abdominal adipose tissue has rarely been attempted. Our object is to determine the impact of abdominal adiposity on pulmonary function by directly measuring abdominal adipose tissue with abdominal computed tomography (CT). In this cross-sectional study, we included never-smokers between the ages of 18 and 85 yr, who had undergone spirometry and abdominal adipose tissue analysis with CT scans during November 1, 2005 to October 31, 2009 as part of the comprehensive health examination. Among a total of 3,469 participants, 890 (25.7%) were male. The mean body mass index and waist circumference among males and females were 24.6 kg/m(2) and 87.8 cm and 23.0 kg/m(2) and 83.0 cm, respectively. Although total adipose tissue (TAT) of the abdomen in males (269.1 cm(2)) was similar to that in females (273.6 cm(2)), the ratio of visceral adipose tissue (VAT)/subcutaneous adipose tissue (SAT) was different; 0.99 in males and 0.50 in females. In males, TAT, SAT, and VAT were inversely associated with the absolute value of forced vital capacity (FVC), and TAT and VAT were inversely associated with forced expiratory volume in one second (FEV(1)). However, in females, TAT and VAT, but not SAT, were inversely associated with absolute FVC and FEV(1) values. In conclusion, the amount of abdominal adipose tissue directly measured using CT is inversely associated with lung function.