Alejandra López-Giraldo

Network medicine, multimorbidity and the lung in the elderly

Noncommunicable diseases, including cardiovascular, metabolic and respiratory diseases, among others, are the major medical challenge of the 21st century. Most noncommunicable diseases are related to the ageing process and often co-occur in the same individual. However, it is unclear whether the index disease is somehow influencing the development of the other ones (comorbidity) or whether all of them (including the index disease) simply represent the clinical expression of pathological ageing (multimorbidity). The pathobiology of ageing, chronic obstructive pulmonary disease (COPD) and concomitant disorders is complex. A new field of research, known as systems biology if applied to model systems or network medicine if applied to human beings, has emerged over the past decade or so, to address biological complexity in a holistic, integrated way. It offers, therefore, great potential to decipher the relationship between ageing, COPD and comorbidities/multimorbidities. In this State of the Art review we present the basic concepts of systems biology, use some examples to illustrate the potential of network medicine to address complex medical problems, and review some recent publications that show how a systems-based research strategy can contribute to improve our understanding of multimorbidity and age-related respiratory diseases. Systems medicine can tackle the complexity of noncommunicable diseases: ageing and major chronic respiratory diseases http://ow.ly/ysZkN

Influence of Previous Use of Inhaled Corticoids on the Development of Pleural Effusion in Community-acquired Pneumonia

RATIONALE Previous use of inhaled corticosteroids (ICS) in patients with chronic obstructive pulmonary disease has been associated with increased risk of community-acquired pneumonia. However, ICS have been associated with fewer pneumonia complications and decreased risk of pneumonia-related mortality. OBJECTIVES The objective of the study was to assess the influence of previous use of ICS on the incidence of parapneumonic effusion in patients with different baseline respiratory disorders. METHODS We conducted a single-center cohort study of 3,612 consecutively collected patients diagnosed with community-acquired pneumonia. We assessed clinical, radiographic, and pleural-fluid chemistry and microbiologic variables. Patients were classified according to whether or not they received prior ICS treatment. MEASUREMENTS AND MAIN RESULTS A total of 633 patients (17%) were treated with corticosteroids before the diagnosis of pneumonia (chronic obstructive pulmonary disease, 54%; asthma, 13%). Incidence of parapneumonic effusion was lower in patients with ICS use compared with non-ICS patients (5% vs. 12%; P < 0.001). After matching according to propensity scores (n = 640), prior treatment with corticosteroids was still significantly associated with a lower incidence of parapneumonic effusion (odds ratio, 0.40; 95% confidence interval, 0.23-0.69; P = 0.001) compared with patients without ICS treatment. Prior ICS treatment was associated with higher levels of glucose (P = 0.003) and pH (P = 0.02), and lower levels of protein (P = 0.01) and lactic acid dehydrogenase (P = 0.007) in the pleural fluid. CONCLUSIONS Prior treatment with ICS in a population of patients with different respiratory chronic disorders who develop pneumonia is associated with lower incidence of parapneumonic effusion.

Network Analysis of Lung Transcriptomics Reveals a Distinct B-Cell Signature in Emphysema

RATIONALE Chronic obstructive pulmonary disease (COPD) is characterized by chronic airflow limitation caused by a combination of airways disease (bronchiolitis) and parenchymal destruction (emphysema), whose relative proportion varies from patient to patient. OBJECTIVES To explore and contrast the molecular pathogenesis of emphysema and bronchiolitis in COPD. METHODS We used network analysis of lung transcriptomics (Affymetrix arrays) in 70 former smokers with COPD to compare differential expression and gene coexpression in bronchiolitis and emphysema. MEASUREMENTS AND MAIN RESULTS We observed that in emphysema (but not in bronchiolitis) (1) up-regulated genes were enriched in ontologies related to B-cell homing and activation; (2) the immune coexpression network had a central core of B cell-related genes; (3) B-cell recruitment and immunoglobulin transcription genes (CXCL13, CCL19, and POU2AF1) correlated with emphysema severity; (4) there were lymphoid follicles (CD20(+)IgM(+)) with active B cells (phosphorylated nuclear factor-κB p65(+)), proliferation markers (Ki-67(+)), and class-switched B cells (IgG(+)); and (5) both TNFRSF17 mRNA and B cell-activating factor protein were up-regulated. These findings were by and large reproduced in a group of patients with incipient emphysema and when patients with emphysema were matched for the severity of airflow limitation of those with bronchiolitis. CONCLUSIONS Our study identifies enrichment in B cell-related genes in patients with COPD with emphysema that is absent in bronchiolitis. These observations contribute to a better understanding of COPD pathobiology and may open new therapeutic opportunities for patients with COPD.

Lung Function Abnormalities are Highly Frequent in Patients with Heart Failure and Preserved Ejection Fraction

BACKGROUND Heart failure with preserved ejection fraction (HFPEF) is the most prevalent form of heart failure in outpatients. Yet, the pathophysiology of this syndrome is unclear and pharmacological treatment does not improve prognosis. Because breathlessness during activities of daily living is the most frequent complaint of patients with HFPEF, we hypothesised that lung function may be often abnormal in these patients due to either a direct effect of HFPEF and/or shared risk factors. In this study we explore the frequency, type and severity of lung function abnormalities in HFPEF. METHODS We measured forced spirometry, static lung volumes, pulmonary diffusing capacity (DL(CO)) and arterial blood gases in 69 outpatients with newly diagnosed symptomatic HFPEF. RESULTS We found that 94% of the patients showed abnormalities in at least one of the lung function measurements obtained: spirometry was abnormal in 59%, DL(CO) in 83% and arterial hypoxaemia was present in 62%. Their severity varied between patients, they were more prevalent in patients with NYHA functional class III/IV, and most often they were undiagnosed and untreated. CONCLUSIONS Lung function abnormalities are very frequent in HFPEF patients. A greater awareness among clinicians may contribute to improve their management and health status.

The inflammasome pathway in stable COPD and acute exacerbations

Chronic obstructive pulmonary disease (COPD) is characterised by pulmonary and systemic inflammation that bursts during exacerbations of the disease (ECOPD). The NLRP3 inflammasome is a key regulatory molecule of the inflammatory response. Its role in COPD is unclear. We investigated the NLRP3 inflammasome status in: 1) lung tissue samples from 38 patients with stable COPD, 15 smokers with normal spirometry and 14 never-smokers; and 2) sputum and plasma samples from 56 ECOPD patients, of whom 41 could be reassessed at clinical recovery. We observed that: 1) in lung tissue samples of stable COPD patients, NLRP3 and interleukin (IL)-1β mRNA were upregulated, but both caspase-1 and ASC were mostly in inactive form, and 2) during infectious ECOPD, caspase-1, oligomeric ASC and associated cytokines (IL-1β, IL-18) were significantly increased in sputum compared with clinical recovery. The NLRP3 inflammasome is primed, but not activated, in the lungs of clinically stable COPD patients. Inflammasome activation occurs during infectious ECOPD. The results of this study suggest that the inflammasome participates in the inflammatory burst of infectious ECOPD. The NLRP3 inflammasome is primed in stable COPD lungs, then activated during infectious exacerbation http://ow.ly/Wopi300DXcT

Hyperammonemic encephalopathy due to a urinary diversion: an uncommon cause of reversible dementia.

that he was not being watched. Behaviors included teasing one resident about his sex life, gently pulling on another resident’s ear, stroking another sleeping resident’s face with a piece of paper, and gently kicking another resident in the leg. On several other occasions, he was reported to have rattled a bird cage on the unit. None of these behaviors resulted in any injury, and he never gave the appearance of being angry or of trying to inflict harm. Medications and laboratory levels were noncontributory, and there was no evidence of intercurrent illness. Extensive inquiry revealed that these behaviors were completely out of character for him. The behavioral problems did not respond at all to behavioral interventions, and a trial of beta-blockers was abandoned because of bradycardia. He was eventually started on valproic acid, which was titrated to a maximum dose of 750 mg twice a day. Upon attaining therapeutic steady-state serum levels (60–80mg/mL), the taunting behavior ceased almost completely and had not recurred over the following 3 months.

Distribution, temporal stability and association with all-cause mortality of the 2017 GOLD groups in the ECLIPSE cohort

BACKGROUND In 2017, the Global Initiative for Chronic Obstructive Lung Disease (GOLD) proposed a new classification of patients with chronic obstructive pulmonary disease (COPD). MATERIAL AND METHODS We contrasted the distribution of COPD patients according to GOLD 2017 and 2011 classifications, the temporal stability of the 2017 groups during 3 years follow-up and their association with all-cause mortality in the ECLIPSE cohort. RESULTS We found that GOLD 2017: (1) switched a substantial proportion of GOLD 2011C and D patients to A and B groups at recruitment; (2) about half of A, B and D patients remained in the same group at the end of follow-up, whereas 74% of C patients (the smallest group of all) changed, either because exacerbation rate decreased or dyspnea increased; and, (3) all-cause mortality by group was not significantly different between GOLD 2011 and 2017. Of note, mortality in B (16%) and D patients (18%) was similar, both with similar severity of airflow limitation, the best individual mortality risk factor. CONCLUSIONS These results illustrate the cross-sectional and longitudinal effects of excluding FEV1 from GOLD 2017, and highlight both the clinical relevance of symptom assessment in the management of COPD and the prognostic capacity of FEV1.

Characterization, localization and comparison of c-Kit+ lung cells in never smokers and smokers with and without COPD

Backgroundc-Kit + lung stem cells have been described in the human healthy lung. Their potential relation with smoking and/or chronic obstructive pulmonary disease (COPD) is unknown.MethodsWe characterized and compared c-Kit+ cells in lung tissue of 12 never smokers (NS), 15 smokers with normal spirometry (S) and 44 COPD patients who required lung resectional surgery. Flow cytometry (FACS) was used to characterize c-Kit+ cells in fresh lung tissue disaggregates, and immunofluorescence (IF) for further characterization and to determine their location in OCT- embedded lung tissue.ResultsWe identified 4 c-Kit+ cell populations, with similar proportions in NS, S and COPD: (1) By FACS, c-Kithigh/CD45+ cells (4.03 ± 2.97% (NS), 3.96 ± 5.30% (S), and 5.20 ± 3.44% (COPD)). By IF, these cells were tryptase+ (hence, mast cells) and located around the airways; (2) By IF, c-Kitlow/CD45+/triptase- (0.07 ± 0.06 (NS), 0.03 ± 0.02 (S), and 0.06 ± 0.07 (COPD) cells/field), which likely correspond to innate lymphoid cells; (3) By FACS, c-Kitlow/CD45-/CD34+ (0.95 ± 0.84% (NS), 1.14 ± 0.94% (S) and 0.95 ± 1.38% (COPD)). By IF these cells were c-Kitlow/CD45-/CD31+, suggesting an endothelial lineage, and were predominantly located in the alveolar wall; and, (4) by FACS, an infrequent c-Kitlow/CD45-/CD34- population (0.09 ± 0.14% (NS), 0.08 ± 0.09% (S) and 0.08 ± 0.11% (COPD)) compatible with a putative lung stem cell population. Yet, IF failed to detect them and we could not isolate or grow them, thus questioning the existence of c-Kit+ lung stem-cells.ConclusionsThe adult human lung contains a mixture of c-Kit+ cells, unlikely to be lung stem cells, which are independent of smoking status and/or presence of COPD.