Lung involvement in diabetes: does it matter?

Impact of Diabetes on Persistent Radiological Abnormalities and Pulmonary Diffusion Dysfunction in COVID-19 Survivors: A 3-Year Prospective Cohort Study

RATIONALE AND OBJECTIVES

Little is known about the long-term impact of diabetes on lung impairment in COVID-19 survivors over a three-year period. This study evaluated the long-term impact of diabetes on persistent radiological pulmonary abnormalities and lung function impairment in COVID-19 survivors over three years.

MATERIALS AND METHODS

In this prospective, multicenter, cohort study, pulmonary sequelae were compared between COVID-19 survivors with and without diabetes. Serial chest CT scans, symptom questionnaires and pulmonary function tests were obtained 6 months, 12 months, 2 years and 3 years post-discharge. The independent predictors for lung dysfunction at the 3-year follow-up were analyzed.

RESULTS

A total of 278 COVID-19 survivors (63 [IQR 57-69] year-old, female: 103 [37.0%]) were included. At the 3-year follow-up, individuals in the diabetes group had higher incidences of respiratory symptoms, radiological pulmonary abnormalities and pulmonary diffusion dysfunction than those in the control group. Diabetes (OR: 2.18, 95% CI: 1.04-4.59, p = 0.034), allergy (OR: 2.26, 95% CI: 1.09-4.74, p = 0.029), female (OR: 2.70, 95% CI: 1.37-5.29, p = 0.004), severe COVID-19 (OR: 4.10, 95% CI: 1.54-10.93, p = 0.005), and fibrotic-like CT changes (OR: 5.64, 95% CI: 2.28-13.98, p < 0.001) were independent predictors of pulmonary diffusion dysfunction in COVID-19 survivors.

CONCLUSION

These results highlight the long-term deleterious effect of diabetes status on radiological pulmonary abnormalities and pulmonary dysfunction in COVID-19 survivors. This study provides important evidence support for long-term monitoring of lung abnormalities in COVID-19 recovery survivors with diabetes.

Evaluation of bi-directional causal association between obstructive sleep apnoea syndrome and diabetic microangiopathy: a Mendelian randomization study

Background

The relationship between obstructive sleep apnea syndrome (OSAS) and diabetic microangiopathy remains controversial.

Objective

This study aimed to use bidirectional two-sample Mendelian Randomization (MR) to assess the causal relationship between OSAS and diabetic microangiopathy.

Methods

First, we used the Linkage Disequilibrium Score Regression(LDSC) analysis to assess the genetic correlation. Then, the bidirectional two-sample MR study was conducted in two stages: OSAS and lung function-related indicators (forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1)) were investigated as exposures, with diabetic microangiopathy as the outcome in the first stage, and genetic tools were used as proxy variables for OSAS and lung function-related measures in the second step. Genome-wide association study data came from the open GWAS database. We used Inverse-Variance Weighted (IVW), MR-Egger regression, Weighted median, Simple mode, and Weighted mode for effect estimation and pleiotropy testing. We also performed sensitivity analyses to test the robustness of the results. Furthermore, we performed multivariate and mediation MR analyses.

Results

In the LDSC analysis, We found a genetic correlation between OSAS, FVC, FEV 1, and diabetic microangiopathy. In the MR analysis, based on IVW analysis, genetically predicted OSAS was positively correlated with the incidence of diabetic retinopathy (DR), diabetic kidney disease (DKD), and diabetic neuropathy (DN). In the subgroup analysis of DR, there was a significant causal relationship between OSAS and background diabetic retinopathy (BDR) and proliferative diabetic retinopathy (PDR). The reverse MR did not show a correlation between the incidence of diabetic microangiopathy and OSAS. Reduced FVC had a potential causal relationship with increased incidence of DR and PDR. Reduced FEV1 had a potential causal relationship with the increased incidence of BDR, PDR, and DKD. Multivariate MR analysis showed that the association between OSAS and diabetic microangiopathy remained significant after adjusting for confounding factors. However, we did not find the significant mediating factors.

Conclusion

Our results suggest that OSAS may be a cause of the development of diabetic microangiopathy, and OSAS may also be associated with a high risk of diabetic microangiopathy, providing a reference for a better understanding of the prevention of diabetic microangiopathy.

Non-apoptotic programmed cell deaths in diabetic pulmonary dysfunction: the new side of advanced glycation end products

Diabetes mellitus (DM) is a chronic metabolic disorder that affects multiple organs and systems, including the pulmonary system. Pulmonary dysfunction in DM patients has been observed and studied for years, but the underlying mechanisms have not been fully understood. In addition to traditional mechanisms such as the production and accumulation of advanced glycation end products (AGEs), angiopathy, tissue glycation, oxidative stress, and systemic inflammation, recent studies have focused on programmed cell deaths (PCDs), especially the non-apoptotic ones, in diabetic pulmonary dysfunction. Non-apoptotic PCDs (NAPCDs) including autophagic cell death, necroptosis, pyroptosis, ferroptosis, and copper-induced cell death have been found to have certain correlations with diabetes and relevant complications. The AGE-AGE receptor (RAGE) axis not only plays an important role in the traditional pathogenesis of diabetes lung disease but also plays an important role in non-apoptotic cell death. In this review, we summarize novel studies about the roles of non-apoptotic PCDs in diabetic pulmonary dysfunction and focus on their interactions with the AGE-RAGE axis.

Dynamic diffusion lung capacity of carbon monoxide (DLCO) as a predictor of pulmonary microangiopathy and its association with extra pulmonary microangiopathy in patients with type II diabetes mellitus

BACKGROUND AND AIM

Lung as a target end organ for microvascular disease often remains underdiagnosed. This study aims to assess occurrence of pulmonary microangiopathy among Type 2 diabetes mellitus (T2DM) using dynamic diffusion lung capacity of carbon monoxide (DLCO).

METHODS

A total of 120 participants aged >18 years were enrolled in this study. Group 1 comprised T2DM with microangiopathy (n = 40), group 2 include T2DM without microangiopathy (n = 40), group 3 were healthy controls (n = 40). Individuals with underlying lung disease, smoking history, heart failure, urinary tract infection, macrovascular complications of diabetes, microalbuminuria due to other causes were excluded from the study. Using electronic spirometry, Forced Expiratory Volume in first second (FEV1), Forced Vital Capacity (FVC) was measured and FEV1/FVC ratio calculated. DLCO (%predicted) using single breath method was measured in sitting position followed by supine position and delta DLCO was calculated. DLCO measured was compared between the three groups.

RESULTS

DLCO (median [IQR]) in sitting (78 [70-82.75]) and supine position (70 [62-84]) among group one was significantly decreased when compared to other two groups (p value < 0.001, p value < 0.001 respectively). Delta DLCO (median, [IQR]) among patients with diabetic microangiopathy (-6 [-8 to -2]) was significant on comparison with group two (4[2,6]) and control group (5[4,6]) (p < 0.001). Negative delta DLCO reflecting pulmonary microangiopathy was significantly associated with extrapulmonary microangiopathy (p value = 0.027).

CONCLUSION

Postural variation in DLCO is a useful non-invasive test for identifying pulmonary microangiopathy among T2DM patients. Presence of pulmonary microangiopathy has significant association with diabetic nephropathy and retinopathy.

Chronic Diabetes Complications: The Need to Move beyond Classical Concepts

Chronic-diabetes-related complications simultaneously compromise both the micro- and macrovascular trees, with target organs considered as the paradigm of large vessel injury also entailing microangiopathic changes. However, complications independent or partially independent from vascular damage are often overlooked. This includes neuronal dysfunction (e.g., retinal neurodegeneration), interstitial injury (e.g., tubulointerstitial disease), metabolic damage (e.g., in the heart and liver), and nonclassical conditions such as cognitive decline, impaired pulmonary function, or increased risk of cancer. In this scenario, researchers, endocrinologists and primary care physicians should have a holistic view of the disease and pay further attention to all organs and all potential clinical repercussions, which would certainly contribute to a more rational and integrated patient health care.

Diagnosis and Significance of Pulmonary Microvascular Disease in Diabetes

OBJECTIVE

To determine whether pulmonary microvascular disease is detectable in subjects with diabetes and associated with diminished exercise capacity using a novel echocardiographic marker quantifying the pulmonary transit of agitated contrast bubbles (PTAC).

RESEARCH DESIGN AND METHODS

Sixty participants (40 with diabetes and 20 control subjects) performed cardiopulmonary (maximal oxygen consumption [VO₂peak]) and semisupine bicycle echocardiography exercise tests within a 1-week period. Pulmonary microvascular disease was assessed using PTAC (the number of bubbles traversing the pulmonary circulation to reach the left ventricle, categorized as low PTAC or high PTAC). Echocardiographic measures of cardiac output, pulmonary artery pressures, and biventricular function were obtained during exercise.

RESULTS

Subjects with diabetes and control subjects were of similar age (44 ± 13 vs. 43 ± 13 years, P = 0.87) and sex composition (70% vs. 65% male, P = 0.7). At peak exercise, low PTAC was present in more participants with diabetes than control subjects (41% vs. 12.5%, χ²P = 0.041) and, in particular, in more subjects with diabetes with microvascular complications compared with both those without complications and control subjects (55% vs. 26% vs. 13%, χ²P = 0.02). When compared with high PTAC, low PTAC was associated with a 24% lower VO₂peak (P = 0.006), reduced right ventricular function (P = 0.015), and greater pulmonary artery pressures during exercise (P = 0.02).

CONCLUSIONS

PTAC is reduced in diabetes, particularly in the presence of microvascular pathology in other vascular beds, suggesting that it may be a meaningful indicator of pulmonary microvascular disease with important consequences for cardiovascular function and exercise capacity.

Protective effects of SOCS3 overexpression in high glucose‑induced lung epithelial cell injury through the JAK2/STAT3 pathway

Previous studies have suggested that the Janus kinase (JAK)/signal transducers and activators of transcription (STAT) pathway is involved in hyperglycemia-induced lung injury. The present study aimed to investigate the roles of suppressor of cytokine signaling3 (SOCS3) in the regulation of JAK2/STAT3 activation following high glucose (HG) treatment in A549 human pulmonary epithelial cells. Cell viability was evaluated using Cell Counting Kit-8 and lactate dehydrogenase assays. HG-induced inflammatory injury in A549 cells was assessed through the evaluation of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) levels using ELISA. The protein expression levels of SOCS3, JAK2, STAT3, phosphorylated (p)-JAK2 and p-STAT3 were determined using western blot analysis. Cellular viability was significantly decreased, whereas IL-6 and TNF-α levels were significantly increased, following HG stimulation of A549 cells. In addition, the protein levels of SOCS3, p-JAK2 and p-STAT3 were significantly increased in HG-treated cells. Treatment with the JAK2/STAT3 inhibitor tyrphostin AG490, or SOCS3 overexpression, appeared to prevent the HG-induced alterations in protein expression. Furthermore, cellular viability was enhanced, whereas the levels of proinflammatory cytokines were suppressed. These finding suggested the involvement of the SOCS3/JAK2/STAT3 signaling pathway in HG-induced responses in lung cells. Therefore, it may be hypothesized that the inhibition of the JAK2/STAT3 pathway through SOCS3 overexpression may prevent hyperglycemia-induced lung injury, and may have therapeutic potential for the treatment of patients with diabetic lung injury.

Effect of diabetes mellitus on postoperative endoscopic sinus surgery outcomes

BACKGROUND

Endoscopic sinus surgery (ESS) has become the treatment of choice for a variety of nasal conditions. The purpose of this study was to analyze the effect of diabetes mellitus (DM) on postoperative outcomes in ESS.

METHODS

Data on endoscopic sinus surgery performed from 2005 to 2013 were collected from the American College of Surgeons National Surgical Quality Improvement (ACS-NSQIP) database. Two groups were created, based on the presence of a DM diagnosis, and were analyzed for preoperative variables, comorbidities, and postoperative complications using SPSS statistical software.

RESULTS

There were 644 patients included in the analysis, 85 of whom (13.2%) had a diagnosis of DM. Patients with DM were more likely to have higher rates of preoperative dyspnea and hypertension. After accounting for confounding factors, DM patients undergoing ESS were at higher risk of overall medical complications, pneumonia, unplanned reintubation, ventilator use of >48 hours, and mortality. However, after separating patients into outpatient and inpatient groups, DM was found to be an independent predictor of urinary tract infection in outpatients and of ventilator use >48 hours in inpatients.

CONCLUSION

DM patients undergoing ESS are at increased risk for postoperative medical complications. However, DM does not appear to increase the postoperative surgical complication rate in this population. Furthermore, DM does not appear to have an impact on ESS mortality, readmission, or reoperation rates.

Association between lung capacity and abnormal glucose metabolism: findings from China and Australia

OBJECTIVE

Restricted pulmonary function is found among people with diabetes. This study aimed to investigate the dose-response relationship between pulmonary function measurements [forced expiratory volume in one second (FEV1) and forced vital capacity (FVC)] and risk of metabolic syndrome (MS)/type 2 diabetes.

METHODS

A total of 1454 adults in rural Victoria, Australia, and 5824 adults in Nanjing, China, from randomly selected households provided clinical history, oral glucose tolerance test, lipids, anthropometric, blood pressure and spirometric measurements. MS was defined by International Diabetes Federation criteria. Adjusted odds ratios for MS and type 2 diabetes with lung capacity measurements were estimated using logistic regression. Dose-response relationships were explored using the restricted cubic spline models.

RESULTS

There was a nonlinear relationship between FEV1 and the risk of type 2 diabetes and MS (both P < 0·0001) in both the Australian and Chinese populations. The FEV1 associated with the lowest risk of type 2 diabetes and MS was above 2·70 l (95%CI: 2·68 to 2·72 l and 2·65 to 2·76 l in Chinese and Australian populations, respectively). The discrimination of the model could be significantly improved using the FEV1 threshold in both the Australian and Chinese populations.

CONCLUSIONS

In both the Australian and Chinese populations, the risk of type 2 diabetes and MS is lowest with a FEV1 of 2·65-2·76 l. This might be used in clinical practice in different countries as a prompt to screen for type 2 diabetes and MS in patients with obstructive lung disease and to ensure there was no abnormal glucose metabolism before the commencement of steroids if indicated.

Serotonin transporter gene (5-HTT) polymorphism and major depressive disorder in patients in Bogotá, Colombia

<p><strong>Introducción.</strong> El polimorfismo 5-HTT se ha asociado con el trastorno de depresión mayor, aunque el planteamiento ha generado controversia.<br /><strong>Objetivo.</strong> Determinar la asociación del polimorfismo 5-HTT con la depresión mayor en Bogotá, Colombia.<br /><strong>Materiales y métodos.</strong> Se hizo un estudio de casos y controles pareado por sexo y edad (±5 años), con una razón de uno a uno (68:68). El trastorno de depresión mayor se diagnosticó con el cuestionario Mini-International Neuropsychiatric Interview, y, el polimorfismo 5-HTT, mediante reacción en cadena de la polimerasa (PCR).<br /><strong>Resultados.</strong> Las mujeres predominaron entre los participantes (82,4 %). El alelo corto (short, S) predominó en los casos comparados con los controles (S: 72,1 % Vs. 63,2; L (long): 27,9 % Vs. 36,8 %), y el genotipo SL fue más frecuente en los casos (SL: 45,6 % Vs. 36,8 %; LL: 27,9 % Vs. 36,8 %; SS: 26,5 % Vs. 26,5 %), aunque no significativamente. Hubo diferencias significativas en menores de 37 años, con predominio del alelo S en los casos (p=0,0384; odds ratio - OR=2,75; IC95%: 0,88-8,64). El análisis multivariado ajustado por trastornos concomitantes de ansiedad mostró una asociación significativa de la depresión mayor con el genotipo SL (p=0,049; OR=3,20; IC95% 1,003-10,233); el alelo S estuvo cerca de la significación estadística (p=0,063; OR=2,94; IC95% 0,94-9,13), y fue estadísticamente significativo en los casos de menores de 37 años (p=0,026; OR=10,79; IC95% 1,32-80,36).<br /><strong>Conclusiones.</strong> El genotipo SL se asoció con el trastorno de depresión mayor en pacientes de todas las edades. El alelo S se asoció significativamente con el trastorno de depresión mayor en pacientes menores de 37 años al ajustar por trastornos concomitantes de ansiedad.</p>

The Effects of Leucine, Zinc, and Chromium Supplements on Inflammatory Events of the Respiratory System in Type 2 Diabetic Rats

Diabetes mellitus is a major cause of serious micro- and macrovascular diseases that affect nearly every system in the body, including the respiratory system. Non-enzymatic protein glycation due to hyperglycaemic stress has fundamental implications due to the large capillary network and amount of connective tissue in the lung. The current study was designed to determine whether leucine, zinc, and chromium supplementations influence the function and histological structure of the respiratory tract in a rat model of type 2 diabetes. Seventy-seven rats were divided into eleven groups, consisting of 7 animals each. One group served as negative control and insulin and glibenclamide were used as positive control drugs. Thus, eight groups received the nutritional supplements alone or in combination with each other. Nutritional supplements and glibenclamide were added to the drinking water and neutral protamine Hagedorn insulin was subcutaneously injected during the 4 weeks of treatment period. The induction of type 2 diabetes in the rats caused an infiltration of mononuclear cells and edema in the submucosa of the trachea and lung, severe fibrosis around the vessels and airways, and perivascular and peribronchial infiltration of inflammatory cells and fibrin. In the diabetic group, the total inflammation score and Reid index significantly increased. Diabetes induction significantly reduced the total antioxidant status and elevated the lipid peroxidation products in the serum, lung lavage and lung tissue of the diabetic animals. Treatment with nutritional supplements significantly decreased the histopathological changes and inflammatory indices in the diabetic animals. Supplementation of diabetic rats with leucine, zinc, and chromium, alone and in combination, significantly increased the total antioxidant status and lipid peroxidation level in the diabetic animals. The nutritional supplements improved the enzymatic antioxidant activity of catalase, glutathione peroxidase, myeloperoxidase, and superoxide dismutase in the diabetic rats. The present results demonstrate beneficial effects and amelioration of inflammation in the respiratory system of type 2 diabetic rats by leucine, zinc, and chromium supplements, probably due to their hypoglycaemic and antioxidant properties. Using safe and effective nutritional supplements, such as leucine, chromium and zinc, to replace proven conventional medical treatments may help to control diabetes and/or its complications.

Improvement of pulmonary function with arm swing exercise in patients with type 2 diabetes

[Purpose] Obesity and hyperglycemia play roles in the impairment of pulmonary function in type 2 diabetes mellitus (T2DM) patients. Low-intensity exercise is known to reduce body fat and improve hyperglycemia. The arm swing exercise (ASE), a low-intensity exercise, is easy and convenient to perform without any equipment and is suitable for daily practice. Therefore, we aimed to investigate the effects of ASE on lung function and obesity in overweight T2DM patients. [Subjects and Methods] Twenty-four subjects continued their daily life routines for 8 weeks (control period), and then performed ASE for 8 weeks (30 minutes per day, 3 days per week) (ASE period). Pulmonary function tests were performed, and fasting blood glucose, haemoglobin A1c (HbA1c), lipid profiles, high-sensitive C-reactive protein (HSCRP), insulin concentration, and anthropometric parameters were measured before and after each period. [Results] After the ASE period, the forced vital capacity, forced expiratory volume in the first second of expiration, and maximal voluntary ventilation were increased when compared with after the control period. HbA1c, a low-density lipoprotein, malondialdehyde, oxidized glutathione, and the percent body fat were significantly decreased when compared with after the control period. However, other parameters, such as lung volume, anthropometric parameters, and fasting blood glucose, insulin, high-density lipoprotein, triglycerides, total cholesterol and glutathione concentrations, showed no differences between the two periods. [Conclusion] These data suggest that there is improvement of pulmonary functions in T2DM patients after ASE training.

Association of glycemic status with impaired lung function among recipients of a health screening program: a cross-sectional study in Japanese adults

Background

The dose-response relationship between glycemic status and lung function has not been thoroughly investigated. We hypothesized that there are continuous and inverse associations between glycemic measures and lung function tests and examined the hypothesis in Japanese adults.

Methods

We cross-sectionally investigated associations of hemoglobin A1c (HbA1c) and fasting plasma glucose (FPG) with forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) in 3161 adults who participated in a health screening from 2008 to 2011. The study participants included both diabetic and non-diabetic adults. Multiple linear regression analyses were performed to examine the associations.

Results

Inverse associations were observed in both sexes, which were attenuated in women after adjustment for multiple variables. A 1% absolute increase in HbA1c was associated with a −52-mL (95% confidence interval [CI] −111 to 8 mL) difference in FVC and a −25-mL (95% CI −75 to 25 mL) difference in FEV1 in women, and a −128-mL (95% CI −163 to −94 mL) difference in FVC and a −73-mL (95% CI −101 to −44 mL) difference in FEV1 in men. A 10-mg/dL increase in FPG was associated with a −11-mL (95% CI −29 to 8 mL) difference in FVC and a −8-mL (95% CI −24 to 7 mL) difference in FEV1 in women, and a −32-mL (95% CI −44 to −21 mL) difference in FVC and a −19-mL (95% CI −28 to −9 mL) difference in FEV1 in men.

Conclusions

Inverse associations between glycemic measures and lung function were observed. Men seem more susceptible to the alteration in FVC and FEV1 than women.

Association between lung capacity measurements and abnormal glucose metabolism: findings from the Crossroads study

AIM

To examine the association between lung function and metabolic syndrome/Type 2 diabetes.

METHODS

A total of 1454 adults from rural Victoria, Australia, from randomly selected households included in the Crossroads study, provided spirometric measurements including forced vital capacity, forced expiratory volume in 1 s, predicted percentage value of forced expiratory volume in 1 s and forced vital capacity predicted percentage value. Assessments also included HbA(1c), metabolic syndrome components and a 75-g oral glucose tolerance test. The area under the receiver-operating characteristic curves for waist circumference were compared with those for combinations of waist circumference and raw spirometric measures (forced vital capacity and forced expiratory volume in 1 s) for identifying metabolic syndrome or Type 2 diabetes.

RESULTS

Partipants with a greater number of metabolic syndrome components were more likely to have reduced lung function, particularly if Type 2 diabetes was present: the predicted value of forced expiratory volume in 1 s decreased by 5-6% for participants with 2-4 metabolic syndrome components, and by 9% for those with Type 2 diabetes. The risk of metabolic syndrome or Type 2 diabetes was inversely associated with higher spirometry values (forced expiratory volume in 1 s percentage predicted value: odds ratio for 2-4 metabolic syndrome components 0.36-0.21 in women and 0.32-0.30 men; the odds ratio for Type 2 diabetes was 0.36 in women and 0.28 in men). Receiver-operating characteristic curve analysis for identifying metabolic syndrome and Type 2 diabetes revealed significant differences between the area under the receiver-operating characteristic curve with waist circumference alone and that for the combination of waist circumference with lung capacity measures.

CONCLUSION

Pulmonary function is lower in people with metabolic syndrome and Type 2 diabetes. Spirometry variables are independent predictors of metabolic syndrome and Type 2 diabetes.

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.

Alteration of pulmonary function in diabetic nephropathy

BACKGROUND

Type 2 diabetes mellitus is increasing worldwide with an alarming rate. It is associated with the development of various chronic complications. The aim of this study was to explore the alteration of pulmonary function, and its association with renal complications in people with type 2 diabetes mellitus.

METHODS

This cross-sectional study was conducted on three groups; 40 diabetic subjects without nephropathy (urinary albumin<30 mg/day), 40 subjects with nephropathy (urinary albumin≥30 mg/day), and 40 healthy subjects as the control group. The subjects with nephropathy were divided into those with microalbuminuria (urinary albumin=30-300 mg/day) and those with macroalbuminuria (urinary albumin>300 mg/day) .Diabetic subjects were matched to the control group in terms of age, sex, and BMI. Pulmonary function tests were performed and the results were compared between groups.

RESULTS

Forced vital capacity (FVC; % predicted), forced expiratory volume in 1 second (FEV1; % predicted), and peak expiratory flow (PEF; % predicted) were significantly lower in subjects with diabetic nephropathy compared to the healthy controls (P<0.05). Meanwhile, in diabetic subjects, FVC and FEV1 were lower in those with diabetic nephropathy compared to those with normal albumin excretion (P<0.05). On the other hand, FEV1/FVC was significantly higher in diabetic people with nephropathy.Furthermore, a significant difference was observed between FVC and FEV1 in diabetic people with microalbuminuria compared to those with macroalbuminuria.

CONCLUSIONS

This study showed that the pulmonary function was impaired in people with Diabetes. The progression of diabetic nephropathy to more advanced stages was also associated with more impairment of pulmonary function.

Reduced lung diffusion capacity in type 2 diabetes is independent of heart failure

In a case-control analysis comparing 303 patients with diabetes and 303 without (matched on age, race, sex and height), diabetics had reduced lung diffusion (DLCO) independent of smoking, obesity, clinical heart failure, asymptomatic left ventricular systolic and diastolic dysfunction: DLCO (mean±SE: 15.5±0.9 vs. 16.4 ±0.9, p=0.01).

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.

Lung spirometry parameters and diffusion capacity are decreased in patients with Type 2 diabetes

AIMS

In cohort studies, Type 2 diabetes mellitus has been associated with decreased forced 1 s expiratory volume and forced vital capacity. We examined if forced vital capacity, forced 1 s expiratory volume and diffusion lung capacity correlate with diabetes mellitus across different races in a clinical setting.

METHODS

We examined the medical records of 19,882 adults 18-97 years of age in our centre from 1 January 2000 to 1 May 2009. After excluding patients with diseases causing abnormal lung function, 4164 subjects were available for analysis. We used multiple linear regressions to examine cross-sectional differences in forced vital capacity, forced 1 s expiratory volume and carbon monoxide diffusing capacity between patients with and without diabetes mellitus, after adjustment for age, sex, race, height, smoking, BMI and heart failure.

RESULTS

Patients with diabetes (n = 560) were older (62 ± 12 vs. 55 ± 16 years), more likely to be men (56 vs. 43%), overweight (BMI 31.7 ± 8.5 vs. 27.3 ± 6.7 kg/m2 ), have heart failure (33 vs. 14%) and less likely to be Caucasians (65 vs. 76%) and never smokers (66 vs. 72%) compared with patients without diabetes (n = 3604). The mean unadjusted values in patients with diabetes vs. those without were: forced vital capacity 2.78 ± 0.91 vs. 3.19 ± 1.03 l; forced 1 s expiratory volume 2.17 ± 0.74 vs. 2.49 ± 0.0.83; and carbon monoxide diffusing capacity 16.67 ± 5.53 vs. 19.18 ± 6.72 ml(-1) min(-1) mmHg, all P < 0.0001. These differences remained significant after adjustment for covariates. After race stratification, only Caucasians with diabetes had a significant decrease in all lung function measures.

CONCLUSIONS

Patients with diabetes have decreased lung function compared with those without diabetes. Caucasians with diabetes have more global lung function impairment compared with African-Americans and Hispanics.

Reduced diffusion lung capacity in patients with type 2 diabetes mellitus predicts hospitalization for pneumonia

Among 4164 patients, those with type 2 diabetes mellitus (DM) had lower lung diffusion capacity (DLCO) compared with those without DM (DLCO mean±SE: 15.7±0.3 vs. 17.0±0.2 mL/min/mm Hg, p<0.01). Reduced DLCO predicted hospitalization for pneumonia independent of diabetes control, severity and co-morbidities (OR=2.4, CI 1.08-5.31).

Type II diabetes mellitus is associated with decreased measures of lung function in a clinical setting

AIMS

Type II diabetes mellitus has been associated with reduced forced expiratory volume in first second (FEV(1)) and forced vital capacity (FVC). We investigated if this relationship is maintained in a clinical setting, independent of respiratory infections and heart failure.

METHODS

Pulmonary function tests and discharge summaries of 639 adults 18-80 years of age, of different races/ethnicities, seen at an urban hospital during a two years period were reviewed. After selection of patients based on inclusion/exclusion criteria, 286 patients were included in our analysis. Using multivariable linear regression we examined cross-sectional differences of FEV(1) and FVC between patients with and without diabetes, adjusting for age, sex, race/ethnicity, BMI, smoking and respiratory symptoms.

RESULTS

Patients with diabetes were older (63 ± 1 vs. 56 ± 1), more likely to be African-Americans (30% vs. 25%) and Hispanics (40% vs. 31%), have respiratory symptoms (79% vs. 68%), and a higher BMI (34.2 ± 1.0 vs. 30.1 ± 0.6), compared to patients without diabetes. The distribution of women and smoking among the two groups were similar. The mean unadjusted percent predicted values of FEV(1) and FVC in patients with diabetes were lower than in those without diabetes, and remained significantly reduced after adjustment (77.3 ± 0.5 vs. 82.0 ± 0.3, p < 0.01 for FEV(1) and 73.8 ± 0.6 vs. 82.8 ± 0.3, p < 0.01 for FVC, respectively).

CONCLUSIONS

In a clinical setting, patients with diabetes have decreased lung function compared to their non-diabetic counterparts, independent of respiratory infections and heart failure.

Systematic review of the association between lung function and Type 2 diabetes mellitus

AIMS

To describe the association between lung function and Type 2 diabetes mellitus.

METHODS

We identified English language studies evaluating the association between lung function and diabetes mellitus in the MEDLINE database from 1 January 1975 to 31 December 2009. We evaluated study quality based on established criteria (54 studies were reviewed, 34 met the inclusion criteria).

RESULTS

Cross-sectional studies showed that adults with diabetes mellitus have lower forced vital capacity (FVC) and forced expiratory volume in one second (FEV1), with reductions in FVC more consistent than FEV1 and lower diffusion capacity (DLCO) compared with their non-diabetic counterparts. The reduced lung function in patients with diabetes is inversely related to blood glucose levels, duration of diabetes and its severity and is independent of smoking or obesity. Findings in cohort studies have been less consistent, with only a few studies identifying an increased rate of lung function decline in adults with diabetes. In addition, other cohort studies have reported an association between decreased lung function and incident insulin resistance and diabetes. Studies evaluating biological mechanisms to explain the association between lung impairment and diabetes identified microangiopathy of the alveolar capillaries and pulmonary arterioles, chronic inflammation, autonomic neuropathy involving the respiratory muscles, loss of elastic recoil secondary to collagen glycosylation of lung parenchyma, hypoxia-induced insulin resistance and low birthweight, as being associated with both insulin resistance and impaired lung function.

CONCLUSIONS

There is an association between diabetes mellitus and decreased lung function, but the definitive direction as well as the exact pathophysiological mechanism to explain this association requires further investigation.

Inadequate glucose control in type 2 diabetes is associated with impaired lung function and systemic inflammation: a cross-sectional study

Background

Inadequate glucose control may be simultaneously associated with inflammation and decreased lung function in type 2 diabetes. We evaluated if lung function is worse in patients with inadequate glucose control, and if inflammatory markers are simultaneously increased in these subjects.

Methods

Subjects were selected at the Colombian Diabetes Association Center in Bogotá. Pulmonary function tests were performed and mean residual values were obtained for forced expiratory volume (FEV₁₎, forced vital capacity (FVC) and FEV₁/FVC, with predicted values based on those derived by Hankinson et al. for Mexican-Americans. Multiple least-squares regression was used to adjust for differences in known determinants of lung function. We measured blood levels of glycosylated hemoglobin (HBA_1c), interleukin 6 (IL-6), tumor necrosis factor (TNF-α), fibrinogen, ferritin, and C-reactive protein (C-RP).

Results

495 diabetic patients were studied, out of which 352 had inadequate control (HBA_1c > 7%). After adjusting for known determinants of lung function, those with inadequate control had lower FEV₁ (-75.4 mL, IC95%: -92, -59; P < 0.0001) and FVC (-121 mL, IC95%: -134, -108; P < 0,0001) mean residuals, and higher FEV₁/FVC (0.013%, IC95%: 0.009, 0.018, P < 0.0001) residuals than those with adequate control, as well as increased levels of all inflammatory markers (P < 0.05), with the exception of IL-6.

Conclusions

Subjects with type 2 diabetes and inadequate control had lower FVC and FEV₁ than predicted and than those of subjects with adequate control. It is postulated that poorer pulmonary function may be associated with increased levels of inflammatory mediators.

Recombinant decorin ameliorates the pulmonary structure alterations by down-regulating transforming growth factor-beta1/SMADS signaling in the diabetic rats

This study investigated the role of transforming growth factor-beta1 (TGF-beta1)/Smads signaling in the alterations of lung structure and the effect of the exogenous decorin on lung structure modification in streptozotocin (STZ)-induced diabetic rats. Seventy-two Sprague-Dawley rats were evenly divided into four groups: STZ-induced diabetic rats (diabetic control), decorin adenovirus vector (Ad)-treated STZ rats (Ad-DCN), Ad-lacZ-treated STZ rats (Ad-lacZ), and normal controls. At 8, 16, and 28 weeks after STZ treatment, haematoxylin-eosin (H&E) and Masson's trichrome staining were performed to investigate the histological changes of diabetic lungs; Expressions of TGF-beta1 and collagen type IV in the diabetic lung were measured by Western blot and immunohistochemistry. Phosphorylated Smad2 (P-Smad2), one of the major TGF-beta1 receptor substrates, was also detected using Western blot. The histological changes of diabetic lung included obvious inflammatory cell infiltration and moderate expanding of alveolar septum stained as collagen. Immunolabeled collagen type IV increased in the alveolar septa in the diabetic lung. Activities of TGF-beta1/Smads signaling increased in the diabetic lung during the 28 weeks of diabetes (p < 0.05 vs. control), and positive staining of TGF-beta1 was mainly found in the cytoplasm of the infiltrated inflammatory cells. Exogenous decorin effectively suppressed the increased activities of TGF-beta1/Smads signaling and partly attenuated collagen deposits in the alveolar septum. Increased activity of TGF-beta1/Smads signaling might play a critical role in the accumulation of collagen in the diabetic lung. The protective effect of decorin in the diabetic lung is at least partly because of the down-regulation of the TGF-beta1/Smads signaling.

Two-year efficacy and safety of AIR inhaled insulin in patients with type 1 diabetes: An open-label randomized controlled trial

BACKGROUND

Patients with type 1 diabetes require intensive insulin therapy for optimal glycemic control. AIR((R)) inhaled insulin (system from Eli Lilly and Company, Indianapolis, IN) (AIR is a registered trademark of Alkermes, Inc., Cambridge, MA) may be an efficacious and safe alternative to subcutaneously injected (SC) mealtime insulin.

METHODS

This was a Phase 3, 2-year, randomized, open-label, active-comparator, parallel-group study in 385 patients with type 1 diabetes who were randomly assigned to receive AIR insulin or SC insulin (regular human insulin or insulin lispro) at mealtimes. Both groups received insulin glargine once daily. Efficacy measures included mean change in hemoglobin A1C (A1C) from baseline to end point, eight-point self-monitored blood glucose profiles, and insulin dosage. Safety assessments included hypoglycemic events, pulmonary function tests, adverse events, and insulin antibody levels.

RESULTS

In both treatment groups, only 20% of subjects reached the target of A1C <7.0%. A significant A1C difference of 0.44% was seen favoring SC insulin, with no difference between the groups in insulin doses or hypoglycemic events at end point. Patients in both treatment groups experienced progressive decreases in lung function, but larger (reversible) decrements in diffusing capacity of the lung for carbon monoxide (DL(CO)) were associated with AIR insulin treatment. Greater weight gain was seen with SC insulin treatment.

CONCLUSIONS

The AIR inhaled insulin program was terminated by the sponsor prior to availability of any Phase 3 data for reasons unrelated to safety or efficacy. Despite early termination, this trial provides evidence that AIR insulin was less efficacious in lowering A1C and was associated with a greater decrease in DL(CO) and increased incidence of cough than SC insulin in patients with type 1 diabetes.

The metabolic syndrome, diabetes and lung dysfunction

Sleep-disordered breathing and sleep apnoea are conditions frequently associated with comorbidity, including obesity, diabetes, hypertension, insulin resistance (metabolic syndrome) and cardiovascular disease. The diabetic state (type 1 and type 2 diabetes) may be associated to diminished lung function and, in particular, decreased vital capacity, and the association between chronic obstructive pulmonary disease (COPD) and type 2 diabetes may be due to a shared inflammatory process. Also, the alteration in circulating endothelial progenitor cells found in respiratory disease, the metabolic syndrome and cardiovascular disease reflect a common condition of endothelial dysfunction.