Chronic kidney disease: A likely underestimated component of multimorbidity in older patients with chronic obstructive pulmonary disease

Arginine, Transsulfuration, and Folic Acid Pathway Metabolomics in Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

There is an increasing interest in biomarkers of nitric oxide dysregulation and oxidative stress to guide management and identify new therapeutic targets in patients with chronic obstructive pulmonary disease (COPD). We conducted a systematic review and meta-analysis of the association between circulating metabolites within the arginine (arginine, citrulline, ornithine, asymmetric, ADMA, and symmetric, SDMA dimethylarginine), transsulfuration (methionine, homocysteine, and cysteine) and folic acid (folic acid, vitamin B6, and vitamin B12) metabolic pathways and COPD. We searched electronic databases from inception to 30 June 2023 and assessed the risk of bias and the certainty of evidence. In 21 eligible studies, compared to healthy controls, patients with stable COPD had significantly lower methionine (standardized mean difference, SMD = -0.50, 95% CI -0.95 to -0.05, p = 0.029) and folic acid (SMD = -0.37, 95% CI -0.65 to -0.09, p = 0.009), and higher homocysteine (SMD = 0.78, 95% CI 0.48 to 1.07, p < 0.001) and cysteine concentrations (SMD = 0.34, 95% CI 0.02 to 0.66, p = 0.038). Additionally, COPD was associated with significantly higher ADMA (SMD = 1.27, 95% CI 0.08 to 2.46, p = 0.037), SDMA (SMD = 3.94, 95% CI 0.79 to 7.08, p = 0.014), and ornithine concentrations (SMD = 0.67, 95% CI 0.13 to 1.22, p = 0.015). In subgroup analysis, the SMD of homocysteine was significantly associated with the biological matrix assessed and the forced expiratory volume in the first second to forced vital capacity ratio, but not with age, study location, or analytical method used. Our study suggests that the presence of significant alterations in metabolites within the arginine, transsulfuration, and folic acid pathways can be useful for assessing nitric oxide dysregulation and oxidative stress and identifying novel treatment targets in COPD. (PROSPERO registration number: CRD42023448036.).

Development of a new prognostic index PNPI for prognosis prediction of CKD patients with pneumonia at hospital admission

Background

The aim of this study was to investigate the relationship between pneumonia and chronic kidney disease (CKD), to elucidate potential risk factors, and to develop a new predictive model for the poor prognosis of pneumonia in CKD patients.

Method

We conducted a retrospective observational study of CKD patients admitted to Tongji Hospital between June 2012 and June 2022. Demographic information, comorbidities or laboratory tests were collected. Applying univariate and multivariate logistic regression analyses, independent risk factors associated with a poor prognosis (i.e., respiratory failure, shock, combined other organ failure, and/or death during hospitalization) for pneumonia in CKD patients were discovered, with nomogram model subsequently developed. Predictive model was compared with other commonly used pneumonia severity scores.

Result

Of 3,193 CKD patients with pneumonia, 1,013 (31.7%) met the primary endpoint during hospitalization. Risk factors predicting poor prognosis of pneumonia in CKD patients were selected on the result of multivariate logistic regression models, including chronic cardiac disease; CKD stage; elevated neutrophil to lymphocyte ratio (NLR) and D-dimer; decreased platelets, PTA, and chloride iron; and significant symptom presence and GGO presentation on CT. The nomogram model outperformed other pneumonia severity indices with AUC of 0.82 (95% CI: 0.80, 0.84) in training set and 0.83 (95% CI: 0.80, 0.86) in testing set. In addition, calibration curve and decision curve analysis (DCA) proved its efficiency and adaptability.

Conclusion

We designed a clinical prediction model PNPI (pneumonia in nephropathy patients prognostic index) to assess the risk of poor prognosis in CKD patients with pneumonia, which may be generalized after more external validation.

Is There an Association Between Chronic Obstructive Pulmonary Disease and Chronic Renal Failure?

Chronic obstructive pulmonary disease (COPD) is one of the most common diseases worldwide with its prevalence increasing with age. It is commonly comorbid with other diseases and managing patients could be difficult and expensive. Chronic kidney disease (CKD) is often present in COPD patients and may be underdiagnosed, especially if it is mild. This study intended to summarize recent findings showing the correlation between the two diseases. Studies were gathered that were published in the last 11 years, from 2010 to 2021. PubMed was used as the main source of data, but papers from the references of the included other sources were added for thoroughness. Observational studies on examining the prevalence and prognosis of comorbid COPD and CKD published in the English language were included. A higher prevalence of CKD in COPD patients was found in most studies; it was found that a higher risk of mortality is present if these diseases coexist. Further research is required and more extensive prospective studies are needed with matched control groups to support the correlation.

Age-Related Disease Risks in Younger versus Older B-Cell Non-Hodgkin's Lymphoma Survivors

BACKGROUND

Younger cancer survivors may develop age-related diseases due to the cancer treatment that they undergo. The aim of this population-based study is to estimate incidence of age-related diseases besides cardiovascular disease among younger versus older B-cell non-Hodgkin's lymphoma (B-NHL) survivors compared with their respective general population cohorts.

METHODS

Survivors of B-NHL were diagnosed between 1997 and 2015 from the Utah Cancer Registry. Using the Utah Population Database, up to 5 cancer-free individuals from the general population were matched with a B-NHL survivor on sex, birth year, and state of birth. Hazard ratios (HR) for age-related disease outcomes, which were identified from medical records and statewide health care facility data, were estimated using Cox Proportional Hazards models for B-NHL survivors diagnosed at <65 years versus ≥65 years at least 5 years since B-NHL diagnosis.

RESULTS

Comparing 2,129 B-NHL survivors with 8,969 individuals from the general population, younger B-NHL survivors had higher relative risks of acute renal failure [HR, 2.24; 99% confidence interval (CI), 1.48-3.39; P heterogeneity = 0.017), pneumonia (HR, 2.42; 99% CI, 1.68-3.49; P heterogeneity = 0.055), and nutritional deficiencies (HR, 2.08; 99% CI, 1.48-2.92; P heterogeneity = 0.051) ≥5 years after cancer diagnosis.

CONCLUSION

Younger B-NHL survivors had higher relative risks of acute renal failure, pneumonia, and nutritional deficiencies than older B-NHL survivors compared with their respective general population cohorts, ≥5 years after cancer diagnosis.

Acute Beetroot Juice Ingestion Does Not Alter Renal Hemodynamics during Normoxia and Mild Hypercapnia in Healthy Young Adults

Arterial hypercapnia reduces renal perfusion. Beetroot juice (BRJ) increases nitric oxide bioavailability and may improve renal blood flow. We tested the hypothesis that acute consumption of BRJ attenuates both decreases in blood velocity and increases in vascular resistance in the renal and segmental arteries during acute hypercapnia. In fourteen healthy young adults, blood velocity and vascular resistance were measured with Doppler ultrasound in the renal and segmental arteries during five minutes of breathing a carbon dioxide gas mixture (CO₂) before and three hours after consuming 500 mL of BRJ. There was no difference between pre- and post-BRJ consumption in the increase in the partial pressure of end-tidal CO₂ during CO₂ breathing (pre: +4 ± 1 mmHg; post: +4 ± 2 mmHg, p = 0.4281). Segmental artery blood velocity decreased during CO₂ breathing in both pre- (by −1.8 ± 1.9 cm/s, p = 0.0193) and post-BRJ (by −2.1 ± 1.9 cm/s, p = 0.0079), but there were no differences between pre- and post-consumption (p = 0.7633). Segmental artery vascular resistance increased from room air baseline during CO₂ at pre-BRJ consumption (by 0.4 ± 0.4 mmHg/cm/s, p = 0.0153) but not post-BRJ (p = 0.1336), with no differences between pre- and post-consumption (p = 0.7407). These findings indicate that BRJ consumption does not attenuate reductions in renal perfusion during acute mild hypercapnia in healthy young adults.

UUO induces lung fibrosis with macrophage-myofibroblast transition in rats

Progression of chronic kidney disease (CKD) to uremia is often accompanied by varying degrees of lung damage and this is also an important cause of death. Although there are many studies on the mechanism of lung injury, it is not clearly understood. Inflammatory macrophages may associated with fibrosis in the lungs. Here, we investigated the role of macrophage-myofibroblast transition (MMT) in lung fibrosis with unilateral ureteral obstruction (UUO) rats. We found that cells undergoing MMT accounted for an important part of the myofibroblast population, and correlated with lung fibrosis, MMT cells in lungs have a predominant M2 phenotype, and this process was attenuated after treatment with eplerenone. In conclusion, our studies provide a possible mechanism for UUO-induced kidney damage and lung injury, indicating the possibility of using eplerenone, a mineralocorticoid receptor blocker, to treat UUO to reduce kidney damage and protect lung function.

RNA interactions in right ventricular dysfunction induced type II cardiorenal syndrome

Right ventricular (RV) dysfunction induced type II cardiorenal syndrome (CRS) has a high mortality rate, but little attention has been paid to this disease, and its unique molecular characteristics remain unclear. This study aims to investigate the transcriptomic expression profile in this disease and identify key RNA pairs that regulate related molecular signaling networks. We established an RV dysfunction-induced type II CRS mouse model by pulmonary artery constriction (PAC). PAC mice developed severe RV hypertrophy and fibrosis; renal atrophy and dysfunction with elevated creatinine were subsequently observed. Expression profiles in RV and kidney tissues were obtained by whole transcriptome sequencing, revealing a total of 741 and 86 differentially expressed (DE) mRNAs, 159 and 29 DEmiRNAs and 233 and 104 DEcircRNAs between RV and kidney tissue, respectively. Competing endogenous RNA (ceRNA) networks were established. A significant alteration in proliferative, fibrotic and metabolic pathways was found based on GO and KEGG analyses, and the network revealed key ceRNA pairs, such as novel_circ_002631/miR-181a-5p/Creb1 and novel_circ_002631/miR-33-y/Kpan6. These findings indicate that significantly dysregulated pathways in RV dysfunction induced type II CRS include Ras, PI3K/Akt, cGMP-PKG pathways, and thyroid metabolic pathways. These ceRNA pairs can be considered potential targets for the treatment of type II CRS.

Multimorbidity and quality of life after blast-related injury among US military personnel: a cluster analysis of retrospective data

Background

Blast injury emerged as a primary source of morbidity among US military personnel during the recent conflicts in Iraq and Afghanistan, and led to an array of adverse health outcomes. Multimorbidity, or the presence of two or more medical conditions in an individual, can complicate treatment strategies. To date, there is minimal research on the impact of multimorbidity on long-term patient-reported outcomes. We aimed to define multimorbidity patterns in a population of blast-injured military personnel, and to examine these patterns in relation to long-term quality of life (QOL).

Methods

A total of 1972 US military personnel who sustained a blast-related injury during military operations in Iraq and Afghanistan were identified from clinical records. Electronic health databases were used to identify medical diagnoses within the first year postinjury, and QOL was measured with a web-based assessment. Hierarchical cluster analysis methods using Ward’s minimum variance were employed to identify clusters with related medical diagnosis categories. Duncan’s multiple range test was used to group clusters into domains by QOL.

Results

Five distinct clusters were identified and grouped into three QOL domains. The lowest QOL domain contained one cluster with a clinical triad reflecting musculoskeletal pain, concussion, and mental health morbidity. The middle QOL domain had two clusters, one with concussion/anxiety predominating and the other with polytrauma. The highest QOL domain had two clusters with little multimorbidity aside from musculoskeletal pain.

Conclusions

The present study described blast-related injury profiles with varying QOL levels that may indicate the need for integrated health services. Implications exist for current multidisciplinary care of wounded active duty and veteran service members, and future research should determine whether multimorbidity denotes distinct post-blast injury syndromes.

Renal and segmental artery hemodynamic response to acute, mild hypercapnia

Profound increases (>15 mmHg) in arterial carbon dioxide (i.e., hypercapnia) reduce renal blood flow. However, a relatively brief and mild hypercapnia can occur in patients with sleep apnea or in those receiving supplemental oxygen therapy during an acute exacerbation of chronic obstructive pulmonary disease. We tested the hypothesis that a brief, mild hypercapnic exposure increases vascular resistance in the renal and segmental arteries. Blood velocity in 14 healthy adults (26 ± 4 yr; 7 women, 7 men) was measured in the renal and segmental arteries with Doppler ultrasound while subjects breathed room air (Air) and while they breathed a 3% CO₂, 21% O₂, 76% N₂ gas mixture for 5 min (CO₂). The end-tidal partial pressure of CO₂ ([Formula: see text]) was measured via capnography. Mean arterial pressure (MAP) was measured beat to beat via the Penaz method. Vascular resistance in the renal and segmental arteries was calculated as MAP divided by blood velocity. [Formula: see text] increased with CO₂ (Air: 45 ± 3, CO₂: 48 ± 3 mmHg, P < 0.01), but there were no changes in MAP (P = 0.77). CO₂ decreased blood velocity in the renal (Air: 35.2 ± 8.1, CO₂: 32.2 ± 7.3 cm/s, P < 0.01) and segmental (Air: 24.2 ± 5.1, CO₂: 21.8 ± 4.2 cm/s, P < 0.01) arteries and increased vascular resistance in the renal (Air: 2.7 ± 0.9, CO₂: 3.0 ± 0.9 mmHg·cm^-1·s, P < 0.01) and segmental (Air: 3.9 ± 1.0, CO₂: 4.4 ± 1.0 mmHg·cm^-1·s, P < 0.01) arteries. These data provide evidence that the kidneys are hemodynamically responsive to a mild and acute hypercapnic stimulus in healthy humans.

Risk factors of chronic obstructive pulmonary disease exacerbations

Chronic Obstructive Pulmonary Disease (COPD) is a chronic respiratory disease characterised by persistent respiratory symptoms and airflow limitation. COPD has a major impact on public health, mainly because of its increasing prevalence, morbidity and mortality. The natural course of COPD is aggravated by episodes of respiratory symptom worsening termed exacerbations that contribute to disease progression. Acute Exacerbations of COPD (AECOPD) can be triggered by a multitude of different factors, including respiratory tract infections, various exposures, prior exacerbations, non-adherence to treatment and associated comorbidities. AECOPD are associated with an inexorable decline of lung function and a significantly worse survival outcome. This review will summarise the most important aspects regarding the impact of different factors that contribute to COPD exacerbations.

Beyond chronic kidney disease: the diagnosis of Renal Disease in the Elderly as an unmet need. A position paper endorsed by Italian Society of Nephrology (SIN) and Italian Society of Geriatrics and Gerontology (SIGG)

The dramatic increase in prevalence of chronic kidney disease (CKD) with ageing makes the recognition and correct referral of these patients of paramount relevance in order to implement interventions preventing or delaying the development of CKD complications and end-stage renal disease. Nevertheless, several issues make the diagnosis of CKD in the elderly cumbersome. Among these are age related changes in structures and functions of the kidney, which may be difficult to distinguish from CKD, and multimorbidity. Thus, symptoms, clinical findings and laboratory abnormalities should be considered as potential clues to suspect CKD and to suggest screening. Comprehensive geriatric assessment is essential to define the clinical impact of CKD on functional status and to plan treatment. Correct patient referral is very important: patients with stage 4-5 CKD, as well as those with worsening proteinuria or progressive nephropathy (i.e. eGFR reduction > 5 ml/year) should be referred to nephrologist. Renal biopsy not unfrequently may be the key diagnostic exam and should not be denied simply on the basis of age. Indeed, identifying the cause(s) of CKD is highly desirable to perform a targeted therapy against the pathogenetic mechanisms of CKD, which complement and may outperform in efficacy the general measures for CKD.

When kidneys and lungs suffer together

A significant interaction between kidneys and lungs has been shown in physiological and pathological conditions. The two organs can both be targets of the same systemic disease (eg., some vasculitides). Moreover, loss of normal function of either of them can induce direct and indirect dysregulation of the other one. Subjects suffering from COPD may have systemic inflammation, hypoxemia, endothelial dysfunction, increased sympathetic activation and increased aortic stiffness. As well as the exposure to nicotine, all the foresaid factors can induce a microvascular damage, albuminuria, and a worsening of renal function. Renal failure in COPD can be unrecognized since elderly and frail patients may have normal serum creatinine concentration. Lungs and kidneys participate in maintaining the acid-base balance. Compensatory role of the lungs rapidly expresses through an increase or reduction of ventilation. Renal compensation usually requires a few days as it is achieved through changes in bicarbonate reabsorption. Chronic kidney disease and end-stage renal diseases increase the risk of pneumonia. Vaccination against Streptococcus pneumonia and seasonal influenza is recommended for these patients. Vaccines against the last very virulent H1N1 influenza A strain are also available and effective. Acute lung injury and acute kidney injury are frequent complications in critical illnesses, associated with high morbidity and mortality. The concomitant failure of kidneys and lungs implies a multidisciplinary approach, both in terms of diagnostic processes and therapeutic management.