Association of restrictive ventilatory dysfunction with the development of prediabetes and type 2 diabetes in Koreans

Preserved Ratio Impaired Spirometry, Metabolomics, and the Risk of Type 2 Diabetes

CONTEXT

Whether baseline preserved ratio impaired spirometry (PRISm) is associated with the risk of developing type 2 diabetes (T2D) and if this association could be mediated by circulating metabolites remains to be elucidated.

OBJECTIVE

To measure the prospective association of PRISm with T2D and potential metabolic mediators thereof.

METHODS

This study used data from the UK Biobank and included 72 683 individuals without diabetes at baseline. PRISm was defined as the predicted forced expiratory volume in 1 second (FEV1) <80% and the FEV1/forced vital capacity ratio ≥0.70. Cox proportional hazards modeling was performed to assess the longitudinal relation between baseline PRISm and incident T2D. Mediation analysis was used to explore the mediation effects of circulating metabolites in the path from PRISm to T2D.

RESULTS

During a median follow-up of 12.06 years, 2513 participants developed T2D. Individuals who had PRISm (N = 8394) were 47% (95% CI, 33%-63%) more likely to develop T2D compared with those who had normal spirometry (N = 64 289). A total of 121 metabolites showed statistically significant mediation effects in the path from PRISm to T2D (false discovery rate <0.05). Glycoprotein acetyls, cholesteryl esters in large high-density lipoprotein (HDL), degree of unsaturation, cholesterol in large HDL, and cholesteryl esters in very large HDL were the top 5 metabolic markers, with mediation proportions (95% CI) being 11.91% (8.76%-16.58%), 11.04% (7.34%-15.55%), 10.36% (7.34%-14.71%), 9.87% (6.78%-14.09%), and 9.51% (6.33%-14.05%), respectively. A total of 11 principal components that explained 95% variance of the metabolic signatures accounted for 25.47% (20.83%-32.19%) of the relation between PRISm and T2D.

CONCLUSIONS

Our study revealed the association of PRISm with T2D risk and the potential roles of circulating metabolites in mediating this association.

Qianjinweijing Decoction Protects Against Fine Particulate Matter Exposure-mediated Lung Function Disorder

Fine particulate matter (PM_2.5) is well known to impair lung function. Strategies protecting against PM_2.5-exerted lung dysfunction have been less investigated. Qianjinweijing decoction (QJWJ), a decoction of a herbal medicine of natural origin, has been used to treat lung disorders as it inhibits oxidation and inflammation. However, no clinical trial has yet evaluated the role of QJWJ in PM_2.5-induced lung dysfunction. Therefore, we conducted a randomized, double-blind, placebo-controlled trial to assess whether QJWJ provided lung benefits against the adverse effects of PM_2.5 exposure among adults. Eligible participants (n = 65) were recruited and randomized to receive QJWJ decoction (n = 32) or placebo (n = 33) for 4 weeks. The restrictive ventilatory defect (RVD), lung function parameters, and induced sputum were analyzed. The PM_2.5 exposure concentration was significantly associated with the vital capacity (VC), peak expiratory flow (PEF), and forced expiratory flow at 75% of the forced vital capacity (FEF₇₅). The negative associations between PM_2.5 and the lung function parameters were eliminated in response to the QJWJ intervention. Additionally, the percentage of RVD (P = 0.018) and the proportion of eosinophils (Eo%) in induced sputum (P = 0.014) in the QJWJ group was significantly lower than that in the placebo group. This study demonstrated that QJWJ could alleviated PM_2.5-induced lung dysfunction and could be a potential treatment for air pollution-related chronic respiratory disease.

Reduced lung function predicts risk of incident type 2 diabetes: insights from a meta-analysis of prospective studies

Epidemiological studies have repeatedly investigated the association between reduced pulmonary function and incident type 2 diabetes mellitus (T2DM). However, the results have been inconsistent. This meta-analysis aimed to clarify this association with prospective cohort studies. We searched PubMed, Web of Science (ISI), and Google Scholar for all studies (in English) reporting reduced lung function with a risk of T2DM. The measures of lung function included percentage of forced vital capacity for predicted values (FVC_%pre), percentage of forced expiratory volume in the first second after expiration for predicted values (FEV_1%pre) and FEV₁-to-FVC ratio%. Summary risk ratios (RRs) and 95% confidence intervals (CIs) were calculated using fixed-effects or random-effects meta-analyses. A total of 5,480 incident T2DM patients among 88,799 individuals were identified from nine prospective cohort studies. Compared to the highest category of FVC_%pre and FEV_1%pre, the lowest category of FVC_%pre and FEV_1%pre were significantly associated with increased incident T2DM risk (FVC_%pre: RR = 1.49, 95% CI: 1.39-1.59; FEV_1%pre: RR = 1.52, 95% CI: 1.42-1.62). However, no significant relationship was found between the FEV₁/FVC ratio and incident T2DM risk (RR = 1.01, 95% CI: 0.91-1.13). Current evidence suggests that restrictive rather than obstructive impairment of lung function is significantly associated with the incidence of T2DM. Further research is warranted to explore potential mediators of this relationship.

Multiple Beneficial Effects of Laparoscopic Sleeve Gastrectomy for Patients with Obesity, Type 2 Diabetes Mellitus, and Restrictive Ventilatory Dysfunction

BACKGROUND

Some studies have suggested that bariatric surgery improves pulmonary function in patients with obesity, but whether it alleviates pulmonary ventilation disorders in patients with obesity, type 2 diabetes mellitus (T2DM), and restrictive ventilatory dysfunction(RVD) is unclear. To evaluate the effect of laparoscopic sleeve gastrectomy (LSG) in improving pulmonary ventilation function in patients with obesity, T2DM, and RVD.

METHODS

We studied patients with T2DM and RVD (forced vital capacity (FVC) predicted < 80%, forced expiratory volume in one second/forced vital capacity (FEV1/FVC) > 70%) who underwent LSG from March 2018 to January 2020. Baseline data was recorded and follow-up visits were made at 3, 6, 9, and 12 months after surgery to evaluate glucose, hemoglobin A1c (HbA1c), body mass index (BMI), and pulmonary ventilation function. We used multivariate analyses to assess the remission of RVD (reversion of FVC to ≥80% of the predicted value).

RESULTS

We enrolled 33 patients (mean age 46.9±5.2 years, 21 males). Two patients were lost to follow-up and another patient died. Thirty patients completed follow-up; 24 had remission of RVD (24/33, 72.7%). Multivariate Cox regression analysis showed that lower HbA1c (HR=0.35 (0.16 ~ 0.76), p=0.008), reduced waist size (0.9 (0.83 ~ 0.98), p=0.017), and shorter duration of diabetes (0.67(0.47~0.97), p=0.033) were associated with alleviation of pulmonary ventilation function.

CONCLUSIONS

LSG not only controls the body weight and T2DM; it may also relieve pulmonary ventilation dysfunction in patients with obesity, T2DM, and RVD. The waist size, duration of diabetes, and HbA1c before LSG negatively affect recovery of pulmonary ventilation dysfunction.

Bidirectional relationship between diabetes and pulmonary function: a systematic review and meta-analysis

AIM

Evidence of the lungs being a target organ of diabetes-related pathophysiology is increasing, and decreased pulmonary function increases the risk of diabetes after adjusting for demographic and metabolic factors. This systematic review and meta-analysis evaluates the bidirectional relationship between diabetes and pulmonary function.

METHODS

MEDLINE, Embase, The Cochrane Library and Web of Science databases were searched, and all studies describing this bidirectional relationship were identified. Two reviewers independently extracted study characteristics and assessed the risk of bias.

RESULTS

A total of 93 studies were included in the meta-analysis. The pooled weighted mean difference (WMD) between diabetes patients and non-diabetic participants for forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC) were -5.65% and -5.91%, respectively, of predicted values. Diabetes-related microvascular complications and poor glycaemic control were associated with poorer pulmonary function in those with diabetes. In addition, diabetes was associated with a restrictive spirometry pattern (RSP) in both cross-sectional studies [odds ratio (OR): 2.88, 95% confidence interval (CI): 2.18-3.81, I² = 0.0%] and prospective cohort studies [hazard ratio (HR): 1.57, 95% CI: 1.04-2.36]. In five longitudinal studies, the conclusions were inconsistent as to whether or not diabetes accelerates pulmonary function decline. However, every 10% decrease in baseline predicted FVC value was associated with a 13% higher risk of incident diabetes (HR: 1.13, 95% CI: 1.09-1.17, I² = 0.0%).

CONCLUSION

There is a bidirectional relationship between diabetes and pulmonary function. However, further investigations into whether dynamic changes in glycaemic levels before and shortly after diabetes onset mediate the deleterious effects on pulmonary function, or vice versa, are now required.

Chronic obstructive pulmonary disease, lung function and risk of type 2 diabetes: a systematic review and meta-analysis of cohort studies

Background

The association between chronic obstructive pulmonary disease (COPD), lung function and risk of type 2 diabetes mellitus (T2DM) remains controversial. We performed a meta-analysis to clarify this issue.

Methods

The PubMed and EMBASE databases were searched. Cohort studies on COPD, lung function and risk of T2DM in adults were included. A random effects model was adopted to calculate the summary risk ratio (RR) and 95% confidence interval (CI). Dose-response analysis was conducted where possible.

Results

A total of 13 eligible cohort studies involving 307,335 incident T2DM cases and 7,683,784 individuals were included. The risk of T2DM was significantly higher in patients with COPD than those without COPD (RR = 1.25, 95% CI 1.16–1.34). Compared to the highest category of percentage forced vital capacity (FVC%), the lowest category of FVC% was associated with a higher risk of T2DM (RR = 1.43, 95% CI 1.33–1.53). Similarly, the summary RR of T2DM for the lowest versus highest category of percentage forced expiratory volume in 1 s (FEV1%) was 1.49 (95% CI 1.39–1.60). Significant linear associations of FVC% and FEV1% with risk of T2DM were found (P_{non-linearity} > 0.05); the RR of T2DM was 0.88 (95% CI 0.82–0.95) and 0.87 (95% CI 0.81–0.94) per 10% increase in FVC% and FEV1%, respectively. There was a non-significant relationship between the FEV1/FVC ratio and the risk of T2DM.

Conclusions

Both COPD and impaired lung function, especially restricted ventilation dysfunction, could increase the risk of T2DM. However, these findings should be interpreted with caution due to the limited number of studies, and need to be validated by future studies.

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.

Metabolic Syndrome and Pulmonary Function Indices

Background and aims: Metabolic syndrome (MetS) is a collection of metabolic risk factors including increased waist circumference (WC), elevated blood pressure (BP), increased triglyceride (TG), decreased high density lipoprotein (HDL-C) and increased fasting blood sugar (FBS). We aimed to examine the relevance between the MetS and its components with reduced lung functions in adult men.

Material and method: A total of 3899 adult men underwent screening examination between 2015-2016 in a cross-sectional survey.

Results: The mean (± SD) age of our population was 37.25 (± 4.9) years. The overall prevalence of MetS was 7.6%. The total prevalence of reduced lung function in men with MetS was 13.8%. The most common type of reduced lung function was the restrictive pattern (7.1%). The forced expiratory volume of first second (FEV1) and forced vital capacity (FVC) values were significantly lower in men with MetS (both p<0.001). Also these values were significantly lower in diabetic men compared to non-diabetics and those with impaired fasting glucose (IFG). WC and HDL were the most potent predictors of reduced FEV1 and FVC.

Conclusions: We obtained a positive independent association between MetS and reduced lung function in adult men which may be related mainly due to increased WC and decreased HDL.

Adiponectin protects against lung ischemia-reperfusion injury in rats with type 2 diabetes mellitus

Adiponectin (APN) has been associated with the pathogenesis of acute brain, liver and heart injury. However, the role of APN in lung ischemia-reperfusion injury (LIRI) in diabetes mellitus remains unclear. To investigate this, the present study evaluated the effects of APN on lung dysfunction and pathological alterations in rats with type 2 diabetes mellitus via lung ischemia/reperfusion (I/R). The lung‑protective effects of APN globular domain (gAPN) in rats with type 2 diabetes mellitus were also investigated by measuring the oxygenation index, inflammatory cytokines, lung edema, histopathology, oxidative stress, apoptosis and the protein expression levels of phosphorylated 5'adenosine monophosphate‑activated protein kinase (p‑AMPK), endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS). The results of the present study demonstrated that the diabetes mellitus rats + I/R (DIR) group exhibited greater concentrations of tumor necrosis factor‑α and interleukin‑6, and increases in the wet‑weight to dry‑weight ratio, lung injury score, oxidative stress and cellular apoptosis. These effects were accompanied by lower pulmonary oxygenation compared with the normal rat + I/R (NIR) group (P<0.05). Additionally, all of these alterations were attenuated in the NIR + gAPN and DIR + gAPN groups compared with in the NIR and DIR groups, respectively. In the DIR group, the expression levels of p‑AMPK/AMPK and eNOS were significantly downregulated, and the levels of iNOS were upregulated, compared with those of the NIR group. Treatment with APN activated AMPK, increased eNOS expression and attenuated iNOS expression. The results of the present study demonstrated that APN exerted protective effects against LIRI via its anti‑inflammatory, antioxidative stress and anti‑apoptotic activities. These protective effects of APN were eliminated in rats with type 2 diabetes mellitus, in which LIRI was exacerbated. The present study indicated that APN may be a potential therapeutic agent for LIRI in type 2 diabetes mellitus.

Restrictive Spirometry Pattern Is Associated With Increased Arterial Stiffness in Men and Women

BACKGROUND

There is growing evidence that pulmonary function impairment is related to cardiovascular events and death. Some studies have shown that the level of FVC is negatively related to arterial stiffness, but most studies were confined to men, and none of them examined the association of the presence of restrictive spirometry pattern with arterial stiffness. Therefore, this study aimed to investigate the association of restrictive spirometry pattern with arterial stiffness by sex.

METHODS

This study recruited 2,961 subjects after excluding those with (1) obstructive lung disease, as defined by history and pulmonary function test; (2) history of asthma, lung cancer, tuberculosis, coronary heart disease, stroke, or any pulmonary structural deformities; and (3) medications influencing BP, plasma glucose, lipid profile, and pulmonary function test. Restrictive spirometry pattern was diagnosed as an FVC < 80% of the predicted value and an FEV₁/FVC ratio ≥ 70%. Increased arterial stiffness was defined as right brachial ankle pulse wave velocity (baPWV) ≥ 1,400 cm/s.

RESULTS

In both men and women, FVC was negatively associated with the baPWV level. Restrictive spirometry pattern was positively associated with increased arterial stiffness in both men and women (men: OR, 2.16; 95% CI, 1.33-3.50; women: OR, 1.95; 95% CI, 1.02-3.72) after adjustment for other clinical variables.

CONCLUSIONS

Both restrictive spirometry pattern and reduced FVC were associated with a higher risk of arterial stiffness, not only in men but also in women. Clinically, assessment of arterial stiffness might be considered in individuals with restrictive spirometry pattern.

Potential Biochemical Mechanisms of Lung Injury in Diabetes

Accumulating evidence has shown that the lung is one of the target organs for microangiopathy in patients with either type 1 or type 2 diabetes mellitus (DM). Diabetes is associated with physiological and structural abnormalities in the diabetic lung concurrent with attenuated lung function. Despite intensive investigations in recent years, the pathogenic mechanisms of diabetic lung injury remain largely elusive. In this review, we summarize currently postulated mechanisms of diabetic lung injury. We mainly focus on the pathogenesis of diabetic lung injury that implicates key pathways, including oxidative stress, non-enzymatic protein glycosylation, polyol pathway, NF-κB pathway, and protein kinase c pathway. We also highlight that while numerous studies have mainly focused on tissue or cell damage in the lung, studies focusing on mitochondrial dysfunction in the diabetic lung have remained sketchy. Hence, further understanding of mitochondrial mechanisms of diabetic lung injury should provide invaluable insights into future therapeutic approaches for diabetic lung injury.

The temporal relationship between poor lung function and the risk of diabetes

Background

The association between impaired lung function and diabetes risk has been established in the past, however the temporal and causal relationships between the two remain unclear. We assessed the relationship between baseline FEV₁ and FVC and risk of incident diabetes at different time intervals for participants in the Malmö Preventive Project cohort.

Methods

Baseline lung function was assessed in 20,295 men and 7416 women during 1974–1992; mean age 43.4 ± 6.6 and 47.6 ± 7.8, respectively. Sex-specific quartiles of FEV₁%predicted and FVC%predicted were created (Q4 = highest; reference). Follow-up time was divided into 10-year time intervals from baseline examination. Cox proportional hazards regression was used to assess the incidence of diabetes according to quartiles of FEV₁ and FVC%predicted, after adjustments for baseline glucose and potential confounding factors.

Results

Over 37-years’ follow-up there were 3753 and 993 incident diabetes events in men and women, respectively. When comparing FEV₁%predicted in men (Q1 vs. Q4), the HR for diabetes was 1.64 (1.21–2.22) for events <10 years after baseline, 1.52 (1.27–1.81) for events 10–20 years after baseline, 1.39 (1.22–1.59) for events 20–30 years after baseline, and 1.46 (1.08–1.97) for events occurring >30 years after baseline. A broadly similar pattern was seen for FVC%predicted and for women.

Conclusions

Low FEV₁ precedes and significantly predicts future diabetes. This risk is still significant many years after the baseline FEV₁ measurement in middle-aged men. These results suggest that there is a relationship between impaired lung function and diabetes risk beyond the effects of hyperglycemia on lung function.

Electronic supplementary material

The online version of this article (doi:10.1186/s12890-016-0227-z) contains supplementary material, which is available to authorized users.

Association of pulse wave velocity with total lung capacity: A cross-sectional analysis of the BOLD London study

BACKGROUND

Low lung function, measured using spirometry, has been associated with mortality from cardiovascular disease, but whether this is explained by airflow obstruction or restriction is a question that remains unanswered.

OBJECTIVES

To assess the association of total lung capacity (TLC), forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) with several cardio-metabolic and inflammatory markers.

METHODS

In the follow up of the Burden of Lung Disease (BOLD) study in London, acceptable post-bronchodilator spirometric, pulse rate, pulse wave velocity and blood pressure data were obtained from 108 participants. Blood samples for measurement of cardio-metabolic and inflammatory markers were also collected from these participants. Association of lung function and volume with the different biomarkers was examined in multivariable linear regression models adjusted for potential confounders.

RESULTS

Following adjustment for age, sex, height, and ethnicity, TLC (adjusted coefficient = -1.53; 95% CI: -2.57, -0.49) and FVC (adjusted coefficient = -2.66; 95% CI: -4.98, -0.34) were inversely associated with pulse wave velocity, and further adjustment for smoking status, pack-years and body mass index (BMI) did not materially change these results. FEV1 was inversely associated with systolic blood pressure, and adjustment for smoking status, pack-years and BMI made this association stronger (adjusted coefficient = -9.47; 95% CI: -15.62, -3.32).

CONCLUSION

The inverse association of pulse wave velocity, which is a marker of cardiovascular disease, with TLC suggests that the association of the former with low FVC is independent of airflow obstruction. The association between FEV1 with systolic blood pressure after adjustment for FVC suggests an association with airflow obstruction rather than with restricted spirometry.