Pulmonary Function in Patients With Type 1 Diabetes Before and After Simultaneous Pancreas and Kidney Transplantation

The interplay between diabetes mellitus and chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) and diabetes mellitus (DM) are common and chronic disorders. COPD is characterized by persistent respiratory symptoms and airflow limitation due to airway and/or alveolar abnormalities and it is considered currently the fourth leading cause of death worldwide. DM is a systemic disease characterized by a chronic hyperglycemia associated with inflammation and oxidative stress. The relationship between the two conditions is not completely understood and conflicting results are reported in the literature. Many studies have investigated the mechanisms through with the respiratory disease is associated with an increased risk of metabolic condition or whether the incidence risk of COPD in individuals affected by DM is higher. The link between the two chronic conditions has relevant implications in the management of patients affected by the both of them. Respiratory patients should be screened for diabetes mellitus as a frequent comorbidity of lung disease since therapeutic options should be assessed about risk-to-benefit ratios associated with the indication for the steroid use. Furthermore, the role of hyperglycemia on pulmonary function (e.g. infection or inflammatory processes) should be evaluated in DM. Finally, in presence of both diseases potential treatment interactions should be considered. In this overview we explored the common aspects of both clinical chronic illnesses and investigated the interplay between the two conditions.

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.

Airflow Limitation, Fatigue, and Health-Related Quality of Life in Kidney Transplant Recipients

BACKGROUND AND OBJECTIVES

Many kidney transplant recipients suffer from fatigue and poor health-related quality of life. Airflow limitation may be an underappreciated comorbidity among kidney transplant recipients, which could contribute to fatigue and lower health-related quality of life in this population. In this study, we compared the prevalence of airflow limitation between kidney transplant recipients and healthy controls and investigated associations of airflow limitation with fatigue and health-related quality of life in kidney transplant recipients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data from the ongoing TransplantLines Biobank and Cohort study were used. Airflow limitation was defined as forced exhaled volume in 1 second less than the fifth percentile of the general population. Fatigue and health-related quality of life were assessed using checklist individual strength 20 revised (CIS20-R) and Short Form-36 (SF-36) questionnaires.

RESULTS

A total of 539 kidney transplant recipients (58% men; mean age 56±13 years) and 244 healthy controls (45% men; mean age 57±10 years) were included. Prevalence of airflow limitation was higher in kidney transplant recipients than in healthy controls (133 [25%] versus 25 [10%]). In multinomial regression models, airflow limitation was independently associated with fatigue severity (odds ratio moderate fatigue, 1.68; 95% confidence interval, 0.92 to 3.09 and odds ratio severe fatigue, 2.51; 95% confidence interval, 1.39 to 4.55; P=0.007) and lower physical health-related quality of life (-0.11 SDs; 95% confidence interval, -0.19 to -0.02; P=0.01) in kidney transplant recipients. In exploratory mediation analyses, fatigue accounted for 79% of the association of airflow limitation with physical health-related quality of life.

CONCLUSIONS

Airflow limitation is common among kidney transplant recipients. Its occurrence is associated with more than two times higher risk of severe fatigue, and it is associated with lower physical health-related quality of life. Mediation analyses suggest that airflow limitation causes fatigue, which in turn, decreases physical health-related quality of life.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

TransplantLines: The Transplantation Biobank, NCT03272841 PODCAST: This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2021_11_08_CJN06600521.mp3.

Anesthesia for Kidney and Pancreas Transplantation

Kidney transplants are the most common solid organ abdominal transplant and are occasionally performed simultaneously with pancreas transplants in diabetic patients. Preoperative evaluation of potential transplant recipients should focus on the potential for occult cardiovascular disease while also screening for other signs of end-organ dysfunction. Intraoperatively, it is of utmost importance to ensure adequate graft perfusion to limit the risk of postoperative graft dysfunction or rejection. Postoperative care of the kidney or pancreas transplant patient should focus on ensuring normalization of volume status, electrolyte concentrations, and glycemic control.

Transfer factor for carbon monoxide in patients with COPD and diabetes: results from the German COSYCONET cohort

Background

An impairment of CO diffusing capacity has been shown in diabetic patients without lung disease. We analyzed how diffusing capacity in patients with COPD is affected by the concurrent diagnosis of diabetes.

Methods

Data from the initial visit of the German COPD cohort COSYCONET were used for analysis. 2575 patients with complete lung function data were included, among them 358 defined as diabetics with a reported physician diagnosis of diabetes and/or specific medication. Pairwise comparisons between groups and multivariate regression models were used to identify variables predicting the CO transfer factor (TLCO%pred) and the transfer coefficient (KCO%pred).

Results

COPD patients with diabetes differed from those without diabetes regarding lung function, anthropometric, clinical and laboratory parameters. Moreover, gender was an important covariate. After correction for lung function, gender and body mass index (BMI), TLCO%pred did not significantly differ between patients with and without diabetes. The results for the transfer coefficient KCO were similar, demonstrating an important role of the confounding factors RV%pred, TLC%pred, ITGV%pred, FEV₁%pred, FEV₁/FVC, age, packyears, creatinine and BMI. There was not even a tendency towards lower values in diabetes.

Conclusion

The analysis of data from a COPD cohort showed no significant differences of CO transport parameters between COPD patients with and without diabetes, if BMI, gender and the reduction in lung volumes were taken into account. This result is in contrast to observations in lung-healthy subjects with diabetes and raises the question which factors, among them potential anti-inflammatory effects of anti-diabetes medication are responsible for this finding.

Pulmonary capillary permeability and pulmonary microangiopathy in diabetes mellitus

Significant increase in permeability surface (PS) in patients with diabetes confirms pulmonary microcirculation damage in these patients.

Cause-specific mortality by race in low-income Black and White people with Type 2 diabetes

AIM

To investigate, with extended follow-up, cause-specific mortality among low-income Black and White Americans with Type 2 diabetes who have similar socio-economic status.

METHODS

Black and White Americans aged 40-79 years with Type 2 diabetes (n = 12 498) were recruited from community health centres as part of the Southern Community Cohort Study. Multivariable Cox analysis was used to estimate mortality hazard ratios and 95% CIs for subsequent cause-specific mortality, based on both underlying and contributing causes of death.

RESULTS

During the follow-up (median 5.9 years), 13.3% of the study population died. The leading causes of death in each race were ischaemic heart disease, respiratory disorders, cancer, renal failure and heart failure; however, Blacks were at a lower risk of dying from ischaemic heart disease (hazard ratio 0.70, 95% CI 0.54-0.91) or respiratory disorders (hazard ratio 0.70, 0.53-0.92) than Whites but had higher or similar mortality attributable to renal failure (hazard ratio 1.57, 95% CI 1.02-2.40), heart failure (hazard ratio 1.47, 95% CI 0.98-2.19) and cancer (hazard ratio 0.87, 95% CI 0.62-1.22). Risk factors for each cause of death were generally similar in each race.

CONCLUSIONS

These findings suggest that the leading causes of death and their risk factors are largely similar among Black and White Americans with diabetes. For the two leading causes of death in each race, however, ischaemic heart disease and respiratory disorders, the magnitude of risk is lower among Black Americans and contributes to their higher survival rates.

Pulmonary function reduction in diabetes with and without chronic obstructive pulmonary disease

OBJECTIVE

Diabetes damages major organ systems through disrupted glycemic control and increased inflammation. The effects of diabetes on the lung have been of interest for decades, but the modest reduction in pulmonary function and its nonprogressive nature have limited its investigation. A recent systematic review found that diabetes was associated with reductions in forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and diffusing capacity for carbon monoxide of the lung and increased FEV1/FVC. They reported pooled results including few smokers. This study will examine measures of pulmonary function in participants with extensive smoking exposure.

RESEARCH DESIGN AND METHODS

We examined pulmonary function in participants with a >10-pack-year history of smoking with and without diabetes with and without chronic obstructive pulmonary disease (COPD). We measured pulmonary function, exercise capacity, and pulmonary-related quality of life in 10,129 participants in the Genetic Epidemiology of Chronic Obstructive Pulmonary Disease (COPDGene) Study.

RESULTS

Participants with diabetes were observed to have reduced pulmonary function after controlling for known risk factors and also significant reductions in exercise capacity and quality of life across functional stages of COPD.

CONCLUSIONS

Pulmonary function in patients with ≥10 pack-years of smoking and diabetes is reduced, and this decrease is associated with significant reductions in activity-related quality of life and exercise capacity.

Alterations in lung gene expression in streptozotocin-induced diabetic rats

BACKGROUND

Diabetes profoundly affects gene expression in organs such as heart, skeletal muscle, kidney and liver, with areas of perturbation including carbohydrate and lipid metabolism, oxidative stress, and protein ubiquitination. Type 1 diabetes impairs lung function, but whether gene expression alterations in the lung parallel those of other tissue types is largely unexplored.

METHODS

Lung from a rat model of diabetes mellitus induced by streptozotocin was subjected to gene expression microarray analysis.

RESULTS

Glucose levels were 67 and 260 mg/dl (p < 0.001) in control and diabetic rats, respectively. There were 46 genes with at least ± 1.5-fold significantly altered expression (19 increases, 27 decreases). Gene ontology groups with significant over-representation among genes with altered expression included apoptosis, response to stress (p = 0.03), regulation of protein kinase activity (p = 0.04), ion transporter activity (p = 0.01) and collagen (p = 0.01). All genes assigned to the apoptosis and response to stress groups had increased expression whereas all genes assigned to the collagen group had decreased expression. In contrast, the protein kinase activity and ion transporter activity groups had genes with both increased and decreased expression.

CONCLUSIONS

Gene expression in the lung is affected by type 1 diabetes in several specific areas, including apoptosis. However, the lung is resistant to changes in gene expression related to lipid and carbohydrate metabolism and oxidative stress that occur in other tissue types such as heart, skeletal muscle and kidney.

Lung function changes related to diabetes mellitus

Diabetic microangiopathy targets the lung as it does other organs. Even though respiratory dysfunction in most patients with diabetes is subclinical and rarely the presenting complaint, there are several reasons why pulmonary assessment is important: (1) Pulmonary function testing noninvasively quantifies physiological reserves in a large microvascular bed that is not clinically devastated by diabetes. (2) Subclinical loss of pulmonary reserves becomes overtly debilitating under conditions of stress, such as with aging, chronic hypoxia due to lung disease or high altitude exposure, or volume overload secondary to cardiac and renal failure. (3) Unlike myocardial or skeletal muscle function, pulmonary indices are largely independent of physical fitness. (4) Interpretation of pulmonary function indices is not complicated by secondary sequelae of diabetic end-organ failure or prior therapy. Lung function could provide useful measures of the progression of systemic microangiopathy. (5) Chronic use of inhaled insulin may affect long-term pulmonary function, while preexisting pulmonary dysfunction may alter the absorption and bioavailability of inhaled insulin. This review will discuss the changes in lung function observed in diabetes, their underlying mechanisms, and their physiological and clinical implications.