Particulate matter in aerosols produced by two last generation electronic cigarettes: a comparison in a real-world environment

The design of e-cigarettes (e-cigs) is constantly evolving and the latest models can aerosolize using high-power sub-ohm resistance and hence may produce specific particle concentrations. The aim of this study was to evaluate the aerosol characteristics generated by two different types of electronic cigarette in real-world conditions, such as a sitting room or a small office, in number of particles (particles/cm3). We compared the real time and time-integrated measurements of the aerosol generated by the e-cigarette types Just Fog and JUUL. Real time (10s average) number of particles (particles/cm3) in 8 different aerodynamic sizes was measured using an optical particle counter (OPC) model Profiler 212-2. Tests were conducted with and without a Heating, Ventilating Air Conditioning System (HVACS) in operation, in order to evaluate the efficiency of air filtration. During the vaping sessions the OPC recorded quite significant increases in number of particles/cm3. The JUUL e-cig produced significantly lower emissions than Just Fog with and without the HVACS in operation. The study demonstrates the rapid volatility or change from liquid or semi-liquid to gaseous status of the e-cig aerosols, with half-life in the order of a few seconds (min. 4.6, max 23.9), even without the HVACS in operation. The e-cig aerosol generated by the JUUL proved significantly lower than that generated by the Just Fog, but this reduction may not be sufficient to eliminate or consistently reduce the health risk for vulnerable non e-cig users exposed to it.

Understanding Severe Asthma Through Small and Big Data in Spanish Hospitals: The PAGE Study

BACKGROUND

Data on the prevalence of severe asthma (SA) are limited. Electronic health records (EHRs) offer a unique research opportunity to test machine learning (ML) tools in epidemiological studies. Our aim was to estimate the prevalence of SA among asthma patients seen in hospital asthma units, using both ML-based and traditional research methodologies. Our secondary objective was to describe patients with nonsevere asthma (NSA) and SA over a follow-up of 12 months.

METHODS

PAGE is a multicenter, controlled, observational study conducted in 36 Spanish hospitals and split into 2 phases: a cross-sectional phase for estimation of the prevalence of SA and a prospective phase (3 visits in 12 months) for the follow-up and characterization of SA and NSA patients. A substudy with ML was performed in 6 hospitals. Our ML tool uses EHRead technology, which extracts clinical concepts from EHRs and standardizes them to SNOMED CT.

RESULTS

The prevalence of SA among asthma patients in Spanish hospitals was 20.1%, compared with 9.7% using the ML tool. The proportion of SA phenotypes and the features of patients followed up were consistent with previous studies. The clinical predictions of patients' clinical course were unreliable, and ML found only 2 predictive models with discriminatory power to predict outcomes.

CONCLUSION

This study is the first to estimate the prevalence of SA in hospitalized asthma patients and to predict patient outcomes using both standard and ML-based research techniques. Our findings offer relevant insights for further epidemiological and clinical research in SA.

Associations of pre-existing comorbidities and COVID-19 in-hospital mortality: an unCoVer analyses

Background

Accumulated evidence on risk factors for adverse COVID-19 outcomes revealed that old age and male sex are main associates, next to pre-existing comorbidities, as analysed from scattered single cohorts of hospitalised COVID-19 patients of accessible electronic medical records. Hence, evidence from federated analyses is called for to provide a more comprehensive and robust analyses of risk factors.

Methods

Using the unCoVer network, i.e., a research platform of 29 partners for the expert use of patient data as routinely gathered in real-world healthcare settings, present analyses restricted to available data of four hospitals from Spain, Slovakia, Romania and Bosnia and Herzegovina covering 8,287 hospitalised COVID-19 patients. In-hospital death after COVID-19 diagnosis was examined in relation to common pre-existing comorbidities using virtual pooling of logistic regression models adjusted for age and sex.

Results

Patients were on average 60.1 (± 20.9) years, 50.7% were male, almost half (43.3%) had at least one pre-existing comorbidity (17.4% having obesity, 21.9% hypertension, 18.0% diabetes and 13.7% cardiovascular diseases (CVD)), and 12.6% died during hospitalisation. Patients with comorbidities had a higher risk of mortality that was increasing with the number of comorbidities: from a virtual pooled odds ratio of 1.16 (95%CI: 0.96, 1.40) for one vs none to 1.30 (1.04, 1.64) and 2.14 (1.64, 2.79) for two and three or more comorbidities, respectively. Of the comorbidities, highest risk was seen for CVD (1.68; 1.40, 2.01), followed by hypertension (1.40; 1.19, 1.64) and diabetes (1.27; 1.07, 1.50), and the lowest for obesity (1.13; 0.94, 1.37).

Conclusions

By federated analyses, this study confirmed that the number of comorbidities was a strong risk factor for in-hospital death after COVID-19, in particular CVD. The unCoVer platform pursues using scattered data sources by innovative computational resources and integrated information for enhanced impact.

Key messages

Experience of the combined use of the cusp-overlap projection and auricular pacing in transcatheter aortic-valve replacement with the self-expanding valves

Introduction

Need of permanent pacemaker implantation (PPI) continues to be an undesirable side-effect after transcatheter aortic-valve replacement (TAVR), mostly in self-expandable (SE) valves. Recently, different techniques have arisen, as the cusp-overlap projection (COP) to better control TAVR implantation depth, and the sequential atrial pacing (AP) after deployment to test atrioventricular (AV) conduction. However, the combination of both techniques has not been tested yet. We sought to determine if the combination of COP and AP can decrease the need of PPI after SE aortic prothesis.

Methods

We retrospectively studied 253 patients in sinus rhythm who underwent TAVR procedure with SE valves between 2018 and 2021, and compared standard implantation (n=143) with the combined use of COP and AP (n=110). Patients with permanent atrial fibrillation or previous pacemaker were excluded. Assessment included EKG, imaging, immediate and 30-day follow-up. AP was performed after TAVR in the absence of complete AV block at rates of 70 to 120 beats/min (or until AV Block was observed).

Results

Median patient age was 80 [75–85] years old and 52.2% were female. No significant differences could be appreciated in baseline demographics or treatment. Both cohorts had similar EKG intervals and similar rates of conduction disturbances (Table 1). Patients with CO+AP displayed bigger outflow tract perimeters (p=0.003). Also, the CO+AP cohort underwent more frequent predilation prior to valve deployment (p<0.001).

During TAVR complete AV block occurred in 4.6% of the CO+AP cohort vs 14.8% in the standard group (p=0.002). Among patients with transient or no conduction disturbances immediately after deployment, AP showed Wenckebach phenomenon in 22 subjects at a median heart rate of 110 bpm. PPI was considered within 24 hours when Wenckebach phenomenon developed below 90 bpm. Testing atrio-his conduction led to a significant decrease in the next 24-hour surveillance with a temporary pacemaker in the COP+AP cohort (23.1% vs 90.2% in the standard cohort, p<0.0001). Time of hospitalization was significantly reduce in the COP + AP cohort (mean stay 2 [1; 3] days vs 5 [4; 8] days in the standard cohort, p<0.0001), and the total amount of total PPI at that time was still lower CO+AP group (12.7% in CO+AP group vs 21.0% in the standard, p=0.121) (Figure 1).

On a 30-day follow-up, the rate of PPI after TAVR remained significantly decreased in the COP+AP cohort (p=0.039, Figure 1).

Conclusion

Combining COP with AP reduces the need of immediate and short-term PPI and reducing on-admission conduction surveillance and hospitalization stay after self-expandable TAVR.

Funding Acknowledgement

Type of funding sources: None.

Early results of a simplified protocol over standard in patients undergoing transcatheter aortic-valve replacement

Introduction

Transcatheter aortic-valve replacement (TAVR) procedure has been simplified, being now a less-invasive minimalist strategy the standard of treatment. Therefore, length of hospitalization has decreased, and early-discharge (ED) (<72 hour) protocols are in development.

Lately, additional techniques to optimize TAVR procedure have arisen, such as the use of radial approach as the secondary access, conscious sedation, cusp overlap projection (COP) to better control the implantation depth in self-expanding (SE) valves, or atrial pacing (AP) after deployment to test atrioventricular (AV) conduction. With the combination of these 4 maneuvers, we have developed an ED protocol, and hereby present the immediate results.

Methods

We prospectively studied 176 patients who underwent staged and transfemoral TAVR procedure with our novel protocol between May 2020 and December 2021 (Protocol) and compared them with a retrospective cohort of 175 patients who underwent standard TAVR between January 2018 and April 2020 (Standard). The protocol cohort included the use of conscious sedation with midazolam and fentanyl, routine radial approach as the secondary access, use of the CO projection, and AP after deployment in the absence of complete AV block, at rates of 70 to 120 beats/min (or until AV Block was observed) in 10 beats/min increments for a total of 20 beats at each increment. As part of this protocol, patients remained in general cardiology ward, avoiding ICU stay, with rapid recovery and early mobilization (After 6 hours in the absence of bleeding). In the absence of complications patients were discharged within 24–48 hours and reviewed a week and a month later in clinic. Initial assessment included EKG, echocardiogram, in hospital and 30-day follow-up.

Results

Median patient age was 80 years old and 49.9% were female. Despite higher rates of hypertension in the standard cohort (p=0.038), no significant differences could be appreciated in baseline demographics, EKG or imaging findings (Table).

Even with higher rates of predilation, CO and AP, the length of procedure and the use of contrast was lower in the protocol cohort. Rates of intraprocedural AV block were similar among groups (p=p.21), but AP led to a significant lower need of temporary pacemaker surveillance (p<0.0001). The use of radial access also tend to diminish immediate bleeding and vascular complications.

According to protocol, the median length of stay was reduced to 2 [1; 4] days (p<0.0001).

At a 30-day follow up, the incidence of major adverse cardiac events was low and similar among groups (p=0.67) (Figure), with no significant differences in the incidence of permanent pacemaker implantation, heart failure admission, bleeding o vascular complication (Figure)

Conclusion

A simplified TAVR protocol combining radial access, CO, AP can be adopted safely, leading to TAVR patients early discharge, with no major events on an immediate 30-day follow-up.

Funding Acknowledgement

Type of funding sources: None.

Transcatheter aortic-valve replacement with the self-expanding valve Portico in low-risk patients

Background

In the past years, transcatheter aortic-valve replacement (TAVR) has risen as a feasible and safe option for patients with aortic stenosis, been now an option of treatment in low-risk (Euroscore II <4%) patients over 75 years.1

Evidence of this treatment with self-expandable supraanular bioprothesis Evolut have widely proven to be no inferior to surgical valve replacement.2 Nevertheless, experience of the annular self-expandable prothesis Portico available in this population is scarce.

Purpose

We present our early experience with the annular self-expandable prothesis Portico in our low-risk population.

Methods

We retrospectively studied 219 symptomatic low-risk patients with who underwent TAVR procedure with self-expandable valves between 2018 and 2021. Assessment included echocardiogram, immediate and 30-day follow-up, as well as last clinical visit follow-up. 92 subjects received an annular Portico prothesis. Our reference group was the suprannular prothesis Evolut (n=127), already validated for low-risk patients in clinical trials.2

Results

The mean age of the patients was 79 years, 43.4% were women, and all the patients were at low surgical risk (2.2 [1.6; 3.0]). No significant differences could be appreciated in baseline demographics and echocardiographic characteristics except for body mass index (BMI), which was higher in the Portico group (p<0.001) (Table).

Procedure length was similar, with the particular need of higher predilation in the Portico group according to recommendations. Both self-expandable prothesis had similar rates of intraprocedural atrioventricular block, bleeding, vascular complications, stroke, and new onset atrial fibrillation.

Mean aortic-valve gradients before discharge were lower at the suprannular Evolut group than in the annular Portico group, and immediate residual aortic regurgitation was almost inexistent in both groups (Table 1).

At a 30-day follow up, the incidence of major adverse cardiac events was low and similar among groups (p=0.6) (Figure 1), with no significant differences in the incidence of permanent pacemaker implantation, heart failure admission, stroke, bleeding o vascular complication (Figure 1).

Conclusion

Annular aortic self-expandable prothesis Portico is a feasible alternative for patients with AS and low surgical risk who undergo TAVR procedure.

Funding Acknowledgement

Type of funding sources: None.

Analysis of co-isogenic prion protein deficient mice reveals behavioral deficits, learning impairment, and enhanced hippocampal excitability

Background

Cellular prion protein (PrP^C) is a cell surface GPI-anchored protein, usually known for its role in the pathogenesis of human and animal prionopathies. However, increasing knowledge about the participation of PrP^C in prion pathogenesis contrasts with puzzling data regarding its natural physiological role. PrP^C is expressed in a number of tissues, including at high levels in the nervous system, especially in neurons and glial cells, and while previous studies have established a neuroprotective role, conflicting evidence for a synaptic function has revealed both reduced and enhanced long-term potentiation, and variable observations on memory, learning, and behavior. Such evidence has been confounded by the absence of an appropriate knock-out mouse model to dissect the biological relevance of PrP^C, with some functions recently shown to be misattributed to PrP^C due to the presence of genetic artifacts in mouse models. Here we elucidate the role of PrP^C in the hippocampal circuitry and its related functions, such as learning and memory, using a recently available strictly co-isogenic Prnp^0/0 mouse model (Prnp^ZH3/ZH3).

Results

We performed behavioral and operant conditioning tests to evaluate memory and learning capabilities, with results showing decreased motility, impaired operant conditioning learning, and anxiety-related behavior in Prnp^ZH3/ZH3 animals. We also carried in vivo electrophysiological recordings on CA3-CA1 synapses in living behaving mice and monitored spontaneous neuronal firing and network formation in primary neuronal cultures of Prnp^ZH3/ZH3 vs wildtype mice. PrP^C absence enhanced susceptibility to high-intensity stimulations and kainate-induced seizures. However, long-term potentiation (LTP) was not enhanced in the Prnp^ZH3/ZH3 hippocampus. In addition, we observed a delay in neuronal maturation and network formation in Prnp^ZH3/ZH3 cultures.

Conclusion

Our results demonstrate that PrP^C promotes neuronal network formation and connectivity. PrP^C mediates synaptic function and protects the synapse from excitotoxic insults. Its deletion may underlie an epileptogenic-susceptible brain that fails to perform highly cognitive-demanding tasks such as associative learning and anxiety-like behaviors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12915-021-01203-0.

A one-arm surgical trial of obstructive sleep apnea (OSA) patients before and 12 months after Bilateral Internal Ramus Distraction of the mandible (BIRD)

BACKGROUND

An innovative approach for the primary and definitive treatment of obstructive sleep apnea (OSA) in adult patients is presented: Bilateral Internal Ramus Distraction of the mandible (BIRD), which is a slow, progressive and more stable procedure to advance the mandibular bone. This study investigated whether this surgical approach is useful to cure OSA.

METHODS

Study design was of an interventional (surgical) one-arm trial of OSA patients assessed before and 12 months after BIRD. All patients were evaluated by pre- and post-operative polysomnography and three-dimensional scans. The amount of skeletal advancement, percentage of upper airway volume increase and postoperative value of mandibular occlusal plane were the predictor variables. Changes in the apnoea-hypopnoea index (AHI), oxygen desaturation index (ODI), and percentage of time with saturation under 90% (TC90) were the main outcome variables.

FINDINGS

Thirty-two subjects with a mean ± SD age of 41.9 ± 13.3 years and 87.5% male were included, and they were followed-up 32 ± 14.2 months. AHI was 47.9 ± 23.1 per hour before surgery and the Epworth Sleepiness Scale (ESS) was 13.4 ± 4.4. Postoperative AHI was 4.8 ± 5.6 per hour 12 months after surgery (P < 0.001), with 81.2% of the patients considered cured (AHI<5) and 18.8% suffering from a mild-to-moderate residual OSA. ESS decreased to 1.9 ± 1.8 at the end of the surgical treatment (P < 0.001). 3D changes revealed an upper airway volume increase of 188.4% ± 73.5% (P < 0.001).

INTERPRETATION

Lengthening the mandibular ramus by distraction osteogenesis to cure OSA appears to be more effective and safer when compared to other surgical protocols, especially in very severe cases with initial AHI>50/h. Titration of the mandibular advancement weekly using respiratory polygraphy allows better healing control and customization of the skeletal advancement, enhancing the aesthetic result.

[Medicine, epidemiology and humanism before and after COVID-19]

The rapid spread of SARS-CoV-2 requires evidence to help mitigate its global harm. Generating accurate measurements of the appropriate clinical and epidemiological indicators associated with COVID-19 is a necessary step in reducing the current pandemic's burden on individuals and the population at large. These unprecedented times have presented a challenge to chronic disease epidemiologists and have required a practical approach "to do something to help during this disaster." Options include returning to clinical care or resorting to online textbooks and resources for crash courses on outbreak research. However, being aware of the magnitude of individual suffering endured by so many, including many esteemed, close colleagues, becomes a personal challenge of enormous proportions. It is envisaged that the arts and other humanities can help re-establish balance, both during the pandemic and especially after it.

Deficits in coordinated neuronal activity and network topology are striatal hallmarks in Huntington's disease

Background

Network alterations underlying neurodegenerative diseases often precede symptoms and functional deficits. Thus, their early identification is central for improved prognosis. In Huntington’s disease (HD), the cortico-striatal networks, involved in motor function processing, are the most compromised neural substrate. However, whether the network alterations are intrinsic of the striatum or the cortex is not fully understood.

Results

In order to identify early HD neural deficits, we characterized neuronal ensemble calcium activity and network topology of HD striatal and cortical cultures. We used large-scale calcium imaging combined with activity-based network inference analysis. We extracted collective activity events and inferred the topology of the neuronal network in cortical and striatal primary cultures from wild-type and R6/1 mouse model of HD. Striatal, but not cortical, HD networks displayed lower activity and a lessened ability to integrate information. GABA_A receptor blockade in healthy and HD striatal cultures generated similar coordinated ensemble activity and network topology, highlighting that the excitatory component of striatal system is spared in HD. Conversely, NMDA receptor activation increased individual neuronal activity while coordinated activity became highly variable and undefined. Interestingly, by boosting NMDA activity, we rectified striatal HD network alterations.

Conclusions

Overall, our integrative approach highlights striatal defective network integration capacity as a major contributor of basal ganglia dysfunction in HD and suggests that increased excitatory drive may serve as a potential intervention. In addition, our work provides a valuable tool to evaluate in vitro network recovery after treatment intervention in basal ganglia disorders.

Development of two-photon polymerised scaffolds for optical interrogation and neurite guidance of human iPSC-derived cortical neuronal networks

Recent progress in the field of human induced pluripotent stem cells (iPSCs) has led to the efficient production of human neuronal cell models for in vitro study. This has the potential to enable the understanding of live human cellular and network function which is otherwise not possible. However, a major challenge is the generation of reproducible neural networks together with the ability to interrogate and record at the single cell level. A promising aid is the use of biomaterial scaffolds that would enable the development and guidance of neuronal networks in physiologically relevant architectures and dimensionality. The optimal scaffold material would need to be precisely fabricated with submicron resolution, be optically transparent, and biocompatible. Two-photon polymerisation (2PP) enables precise microfabrication of three-dimensional structures. In this study, we report the identification of two biomaterials that support the growth and differentiation of human iPSC-derived neural progenitors into functional neuronal networks. Furthermore, these materials can be patterned to induce alignment of neuronal processes and enable the optical interrogation of individual cells. 2PP scaffolds with tailored topographies therefore provide an effective method of producing defined in vitro human neural networks for application in influencing neurite guidance and complex network activity.

Geographic distribution of chronic obstructive pulmonary disease prevalence in Africa, Asia and Australasia

OBJECTIVE: To visualise spatial data on chronic obstructive pulmonary disease (COPD) prevalence in Africa, Asia and Australasia using a Geographic Information System (GIS) inverse distance weighted (IDW) interpolation technique.DESIGN: Prevalence rates from population surveys on individuals aged ≥40, with spirometry-confirmed COPD, were searched systematically. The prevalence observed in 59 selected surveys and the geographic coordinates of the places where they were conducted informed a GIS computer programme. The prevalence was represented by an ascending chromatic scale (blue-green-yellow-orange-brown-red) in the GIS maps.RESULTS: IDW-interpolation GIS maps were obtained of all the geographic areas investigated, and even from regions lacking data. Areas of high/very high prevalence were found in: Southern Africa and in most of the Central and Eastern Africa regions; in practically all of Central Asia; in the western regions of Southern Asia; in the southern regions of the East European Plain and the West Siberian Plain of Northern Asia; and in the Malay Archipelago. Intermediate prevalence predominated in Oceania and in most of the other regions of Africa and Asia.CONCLUSION: Despite some biases inherent to the interpolation method used in the present study, our approach provided an understandable visual perspective of the COPD prevalence distribution in these geographic regions.

Chronic obstructive pulmonary disease (COPD) in Spain and the different aspects of its social impact: a multidisciplinary opinion document

Chronic obstructive pulmonary disease (COPD) is one of the most prevalent diseases in the World, and one of the most important causes of mortality and morbidity. In adults 40 years and older, it affects more than 10% of the population and has enormous personal, family and social burden. Tobacco smoking is its main cause, but not the only one, and there is probably a genetic predisposition that increases the risk in some patients. The paradigm of this disease is changing in Spain, with an increase of women that has occurred in recent years. Many of the physio pathological mechanisms of this condition are well known, but the psychological alterations to which it leads, the impact of COPD on relatives and caregivers, the limitation of daily life observed in these patients, and the economic and societal burden that they represent for the health system, are not so well-known. A major problem is the high under-diagnosis, mainly due to difficulties for obtaining, in a systematic way, spirometries in hospitals and health-care centers. For this reason, the Fundación de Ciencias de la Salud and the Spanish National Network Center for Research in Respiratory Diseases (CIBERES) have brought together experts in COPD, patients and their organizations, clinical psychologists, experts in health economics, nurses and journalists to obtain their opinion about COPD in Spain. They also discussed the scientific bibliometrics on COPD that is being carried out from the CIBERES and speculated on the future of this condition. The format of the meeting consisted in the discussion of a series of questions that were addressed by different speakers and discussed until a consensus conclusion was reached.

PAGE Study: Summary of a Study Protocol to Estimate the Prevalence of Severe Asthma in Spain Using Big Data Methods

BACKGROUND AND OBJECTIVES

Background: The proposal and the initiative for the Prevalence of Severe Asthma in Hospital Units in Spain (PAGE) study came about because of the widespread implementation of electronic medical records and the limited data available on the prevalence of severe asthma in hospitals in our setting. Objectives: The primary objective was to determine the prevalence of severe asthma in the outpatient clinics of allergy and pulmonology departments in Spain. The secondary objectives were to describe the most prevalent characteristics and phenotypes of severe asthma, to evaluate the selection criteria for receiving approved biological treatments for this disease, and to estimate consumption of resources. Furthermore, digital technology and new data collection sources made it possible to reuse information stored in electronic medical records (Big Data). The study was performed using one such tool, Savana.

METHODS

The PAGE study was a multicenter, nonexperimental, observational, cross-sectional study in the first phase and a prospective study in the second phase. The study was controlled and population-based, with 2-stage selection of patients by random sampling. The research was carried out in 40 hospitals selected using convenience sampling in order to ensure geographical representativeness in Spain.

RESULTS

This manuscript describes the study design and protocol.

CONCLUSIONS

Our study design was sufficiently robust to avoid bias and to establish the prevalence of patients with severe asthma in Spanish hospitals. It was also the first to incorporate new tools that can help in routine clinical practice and research, such as big data analysis software, and to evaluate the reliability and efficiency of these tools.

Combining case-finding methods for COPD in primary care: a large, two-stage design study

BACKGROUND

Underdiagnosis of chronic obstructive pulmonary disease (COPD) is common. We aimed to assess the effectiveness of using the Chronic Obstructive Pulmonary Disease-Population Screener (COPD-PS) questionnaire with pre-bronchodilator (BD) peak expiratory flow (PEF) measurements as a case-finding strategy for COPD in primary care.

METHODS

This was a two-stage, cross-sectional study comprising a population survey in a primary care population aged 35 years without previous COPD, followed by a validation study using COPD-PS 4 or PEF 2.2 l/s·m2, and confirmed by spirometry (post-BD forced expiratory volume in 1 s/forced vital capacity [FEV1/FVC] <0.70). The predictive capacity of the strategy was assessed in a case-control sub-study.

RESULTS

Of a total of 10 071 individuals, 6969 (69.2%) participants were included. Both tests were positive in 4.3% subjects, PEF only in 2.1% and COPD-PS only in 5.1%. Of the 802 with positive screening results, COPD was confirmed using spirometry in 130, accounting for 1.9% of all participants and 16.2% of those who tested positive on COPD-PS or PEF. Among the 130 true-positives, the mean score for the COPD-PS questionnaire was 5.1 l/s·m2 (± standard deviation [SD] 1.7) and 1.9 l/s·m2 (±SD 0.8) for pre-BD PEF, both significantly worse than in the 672 false-positives. The combined use of both screening tests had a sensitivity of 67.5%, a specificity of 71.3% and a diagnostic accuracy of 69.6%.

CONCLUSION

Case finding for COPD using COPD-PS + PEF led to a 90% reduction in the number of spirometry tests performed.

P5621Diagnostic accuracy of resting full-cycle ratio in the non-culprit artery of acute patients

Introduction

Resting full-cycle ratio (RFR) is a novel non-hyperemic index of coronary stenosis severity, independent of the timing within the cardiac cycle. Recent data has demonstrated good correlation between RFR and Fractional Flow Reserve (FFR) in stable coronary disease (SCD). However, there are no data regarding the reliability of RFR in non-culprit arteries of patients presenting with acute myocardial infarction (AMI).

Purpose

To study the diagnostic accuracy of RFR versus FFR in the non-culprit artery in AMI compared to stable lesions.

Methods

RFR, FFR, Coronary Flow Reserve (CFR), Index of Microcirculatory Resistance (IMR), and Resistance Reserve Ratio (RRR) were calculated in 67 patients with AMI and an intermediate lesion in a non-culprit artery (median time from primary PCI to study: 48 hours). Data were compared with those of a retrospective group of 66 patients with SCD.

Results

There was a higher proportion of males among patients of the AMI group (85% vs 62%, p=0.0026). Mean age was 64.5±11 years, being AMI cohort younger at presentation [62±11 vs 67±12 years in SCD cohort (p=0.04)]. Patients with AMI had a significantly lower prevalence of hypertension (52% vs 75%, p=0.006), diabetes (10% vs 32%), p=0.002) and hyperlipemia (37% vs 79%, p=0.002).

Coronary physiology parameters showed a non-normal distribution, and are expressed as median [IQR] (Table 1). In patients with AMI, FFR was lower than in patients with SCD. In contrast, RFR showed no significant difference. Both CFR and RRR were higher in the AMI group. No significant differences in IMR were found between cohorts.

Importantly, in the AMI group the correlation between RFR and FFR was 0.84 and the overall agreement 82%, with rates of false positive and negative of 15% and 3%, respectively. In SCD the correlation was 0.81 with a lower overall agreement of 69%, due mostly to a higher rate of false positive RFR (28%) (Figure 1).

Table 1. Microcirculatory parameters in non-culprit artery (AMI) and stable coronary disease (SCD) AMI (N=66) Stable (N=67) p value FFR 0.84 [0.76–0.9] 0.84 [0.76–0.9] 0.006 RFR 0.89 [0.82–0.94] 0,9 [0.84–0.94] 0.24 CFR 2.2 [1.7–3.1] 1.8 [1.1–2.6] 0.011 IMR 17 [14–27] 25 [14–38] 0.051 RRR 2.7 [2.17 - 3.9] 2.1 [1.4–3.1] 0.005 Median [IQR].

Figure 1. Correlation between RFR and FFR valueS

Conclusions

RFR shows a good correlation with FFR in AMI. Surprisingly, overall agreement is higher in the non-culprit artery in an acute setting, with a lower percentage of false positive results.

Acknowledgement/Funding

None

6115Influence of microvascular function and coronary flow in the diagnostic precision of resting full-cycle ratio

Introduction

Resting full-cycle ratio (RFR) has been recently described as a non-hyperemic index of coronary stenosis with good concordance with Fractional Flow Reserve (FFR). However, there is no information concerning the influence of microvascular function and coronary flow on RFR results.

Purpose

To determine if the accuracy of this novel parameter might be influenced by changes in microvascular function.

Methods

133 patients admitted in our center between July 2016 and December 2017 underwent coronary physiology study of an angiographically intermediate lesion. 67 subjects presented with AMI and an intermediate lesion in a non-culprit artery, and 66 subjects stable coronary disease. We performed FFR, Coronary Flow Reserve (CFR), Index of Microcirculatory Resistance (IMR) and Resistance Reserve Ratio (RRR) in all of them. We calculated RFR retrospectively from the pressure tracings.

Results

Coronary physiology parameters showed a non-normal distribution and are presented as median [IQR]: FFR 0.86 [0.79–0.92]; CFR 2.05 [1.4–2.95]; IMR 20.5 [14–32.55]; RRR 2.5 [1.85–3.63]; RFR 0.897 [0.83–0.94]. Patients with abnormal CFR displayed lower RFR values although FFR was not markedly affected (Table 1). These findings remained irrespective of the clinical scenario at presentation.

61 patients had a CFR lower than 2. Correlation between RFR and FFR was not significantly different in patients with abnormal CFR than in those with normal CFR (0,73 vs 0,88; p=0,067) (Figure 1); however, overall binary agreement between RFR and FFR was worse in patients with a low CFR (69% vs 83%; p=0,047).

48 patients had a high IMR (>25). Linear correlation between RFR and FFR was similar in patients with high and normal IMR (0,81 vs 0,83; p=0,784); likewise, binary concordance showed no significant difference between both groups (77% vs 75%, p=0,78).

The mean difference between RFR and FFR was 0,025. This was only influenced by CFR: patients with a low CFR had a smaller difference than those with a normal CFR (0,012 vs 0,035; p=0,019).

Physiology parameters by CFR group Normal CFR (≥2) Low CFR (<2) P-value FFR 0.88 [0.82–0.93] 0.84 [0.79–0.92] 0.14 RFR 0.91 [0.88–0.95] 0.86 [0.80–0.92] 0.0009 IMR 16.5 [13–27] 25 [16–45.5] 0.002 RRR 3.6 [2.7–4.9] 1.7 [1.3–2.1] <0.0001 Physiological coronary parameters (Median [IQR]) according to CFR.

Correlation between RFR and FFR by CFR

Conclusion

RFR has good overall correlation and concordance with FFR. However, RFR has a lower diagnostic accuracy in patients with a low CFR.

Acknowledgement/Funding

None

Cell Death Mechanisms in Tumoral and Non-Tumoral Human Cell Lines Triggered by Photodynamic Treatments: Apoptosis, Necrosis and Parthanatos

Cell death triggered by photodynamic therapy can occur through different mechanisms: apoptosis, necrosis or autophagy. However, recent studies have demonstrated the existence of other mechanisms with characteristics of both necrosis and apoptosis. These new cell death pathways, collectively termed regulated necrosis, include a variety of processes triggered by different stimuli. In this study, we evaluated the cell death mechanism induced by photodynamic treatments with two photosensitizers, meso-tetrakis (4-carboxyphenyl) porphyrin sodium salt (Na-H₂TCPP) and its zinc derivative Na-ZnTCPP, in two human breast epithelial cell lines, a non-tumoral (MCF-10A) and a tumoral one (SKBR-3). Viability assays showed that photodynamic treatments with both photosensitizers induced a reduction in cell viability in a concentration-dependent manner and no dark toxicity was observed. The cell death mechanisms triggered were evaluated by several assays and cell line-dependent results were found. Most SKBR-3 cells died by either necrosis or apoptosis. By contrast, in MCF-10A cells, necrotic cells and another cell population with characteristics of both necrosis and apoptosis were predominant. In this latter population, cell death was PARP-dependent and translocation of AIF to the nucleus was observed in some cells. These characteristics are related with parthanatos, being the first evidence of this type of regulated necrosis in the field of photodynamic therapy.

Respiratory infection by Corynebacterium striatum: epidemiological and clinical determinants

The increasing prevalence of advanced chronic respiratory disease, with frequent exposure to broad-spectrum antibiotics for repeated and prolonged hospitalizations, favours the emergence of nosocomial respiratory infection by Gram-positive bacteria, such as outbreaks of Corynebacterium striatum. There is little evidence about patterns of respiratory infection, transmission and adaptive ability of this pathogen. Seventy-two C. striatum isolates from 51 advanced respiratory patients, mainly chronic obstructive pulmonary disease, were studied during 38 months. Patients were 74.8 ± 8.6 years old and 81.9% were men, who had required an average of 2.2 hospitalizations and 63.5 days in the hospital in the previous year. Of 49 isolates from 42 patients we were able to identify 12 clones by multilocus sequence analysis (MLSA), nine phenotypic variants and 22 antibiotic susceptibility patterns, and we determined their clinical and epidemiological determinants. MLSA allows identification of the existence of nosocomial outbreaks by transmission of the same or different clones, the persistence of the same clone in the environment or in patient airways for months. The study showed the high variability and adaptive capacity of the isolates, the antibiotic multidrug-resistance in all of them, and their contribution to a high morbidity and mortality (41%) during the study period.

Increased exhaled breath temperature in subjects with uncontrolled asthma

BACKGROUND

Increased vascularity of the airway mucosa in asthma potentially increases heat loss in the airways.

OBJECTIVE

To determine if the inflamed airways of subjects with uncontrolled asthma show increased exhaled breath temperature (EBT).

PATIENTS AND METHODS

In 100 patients with persistent asthma and 50 healthy volunteers, we measured lung function by post-bronchodilator forced spirometry, the asthma control test (ACT) and EBT.

RESULTS

Patients with asthma, of whom 49 (49%) were female, with a mean (± standard error of the mean) age of 44 (±17) years and a predicted forced expiratory volume in one second of 71% (±16), had a significantly increased EBT, particularly those with uncontrolled asthma (n = 50, ACT ≤ 19, EBT 34.9 ± 0.8°C), compared to patients with controlled asthma (n = 50, ACT ≥ 20, EBT 33.7 ± 0.8°C) and healthy volunteers (n = 50, EBT 33.2 ± 0.2°C, P < 0.001).

CONCLUSION

We observed a higher temperature on exhaled breath in subjects with uncontrolled asthma than in subjects with controlled asthma and healthy controls. The increase in exhaled breath temperature may be a proxy for a raised airway inflammatory state in asthma patients.

Percolation of spatially constrained Erdős-Rényi networks with degree correlations

Motivated by experiments on activity in neuronal cultures [ J. Soriano, M. Rodríguez Martínez, T. Tlusty and E. Moses Proc. Natl. Acad. Sci. 105 13758 (2008)], we investigate the percolation transition and critical exponents of spatially embedded Erdős-Rényi networks with degree correlations. In our model networks, nodes are randomly distributed in a two-dimensional spatial domain, and the connection probability depends on Euclidian link length by a power law as well as on the degrees of linked nodes. Generally, spatial constraints lead to higher percolation thresholds in the sense that more links are needed to achieve global connectivity. However, degree correlations favor or do not favor percolation depending on the connectivity rules. We employ two construction methods to introduce degree correlations. In the first one, nodes stay homogeneously distributed and are connected via a distance- and degree-dependent probability. We observe that assortativity in the resulting network leads to a decrease of the percolation threshold. In the second construction methods, nodes are first spatially segregated depending on their degree and afterwards connected with a distance-dependent probability. In this segregated model, we find a threshold increase that accompanies the rising assortativity. Additionally, when the network is constructed in a disassortative way, we observe that this property has little effect on the percolation transition.

A home telehealth program for patients with severe COPD: the PROMETE study

BACKGROUND

Acute exacerbations of chronic obstructive pulmonary disease (AECOP) are key events in the natural history of the disease. Patients with more AECOPD have worse prognosis. There is a need of innovative models of care for patients with severe COPD and frequent AECOPD, and Telehealth (TH) is part of these programs.

METHODS

In a cluster assignment, controlled trial study design, we recruited 60 patients, 30 in home telehealth (HT) and 30 in conventional care (CC). All participants had a prior diagnosis of COPD with a post-bronchodilator forced expiratory volume (FEV1)% predicted <50%, age ≥ 50 years, were on long-term home oxygen therapy, and non-smokers. Patients in the HT group measured their vital signs on a daily bases, and data were transmitted automatically to a Clinical Monitoring Center for followed-up, and who escalated clinical alerts to a Pneumologist.

RESULTS

After 7-month of monitoring and follow-up, there was a significant reduction in ER visits (20 in HT vs. 57 in CC), hospitalizations (12 vs. 33), length of hospital stay in (105 vs. 276 days), and even need for non-invasive mechanical ventilation (0 vs. 8), all p < 0.05. Time to the first severe AECOPD increased from 77 days in CC to 141 days in HT (K-M p < 0.05). There was no study withdrawals associated with technology. All patients showed a high level of satisfaction with the HT program.

CONCLUSIONS

We conclude that HT in elderly, severe COPD patients with multiple comorbidities is safe and efficacious in reducing healthcare resources utilization.

Preoperative treatment with bevacizumab in combination with chemotherapy in patients with unresectable metastatic colorectal carcinoma

PURPOSE

This prospective observational study assessed the efficacy of bevacizumab in combination with chemotherapy as preoperative treatment to downsize tumours for radical resection in patients with unresectable metastatic colorectal cancer (mCRC).

PATIENTS/METHODS

Patients with mCRC initially unresectable according to predefined criteria were included. Preoperative treatment consisted of bevacizumab (5 mg/kg) combined with oxaliplatin- or irinotecan-based chemotherapy, which was followed by surgery in patients showing clinical benefit. Resection rate was the primary endpoint. Response rate (RR) and clinical benefit of preoperative chemotherapy, and overall survival (OS) were secondary endpoints.

RESULTS

A total of 120 eligible patients were included and received preoperative treatment. Chemotherapy was irinotecan-based in 73 (61 %) patients, oxaliplatin-based in 25 (21 %) and 22 (18 %) patients received more than one line. A RR of 30 % and a clinical benefit rate of 73 % were observed with preoperative chemotherapy. Metastatic resection was possible in 61 (51 %) patients. Median OS was 33 months (95 % CI 31-NA months) for patients undergoing surgery, and 15 months (95 % CI 11-25 months) in non-operated patients. Thirty-five patients experienced 59 postoperative complications (morbidity rate 57 %).

CONCLUSION

Preoperative bevacizumab-based chemotherapy offers a high surgical rescue rate in patients with initially unresectable mCRC.

[Comorbidities in patients hospitalized due to chronic obstructive pulmonary disease. A comparative analysis of the ECCO and ESMI studies]

BACKGROUNDS AND OBJECTIVES

The presence of associated diseases is very frequent in patients hospitalized due to exacerbation of COPD. We have studied the comorbidities of patients admitted due to the disease in the Spanish Internal Medicine Services and we have evaluated the variations in regards to a previous study (ECCO study) performed two years earlier.

PATIENTS AND METHODS

A cross-sectional, multicenter and cohort study was performed. Patients hospitalized due to exacerbation of COPD in Spanish Internal Medicine Services were enrolled. All the patients were studied for the presence of comorbidity using the Charlson index and a questionnaire with relevant conditions not included in this index. Furthermore, spirometric data were collected on the duration of the disease or home treatment, among other variables.

RESULTS

A total of 1004 patients (398 in the ECCO study and 606 in the ESMI study) were studied. Of these, 89.4% were males, with mean age of 73 years (SD: 9.5 years). The patients of the ESMI study obtain higher scores on the Charlson index (3.04 vs. 2.71; P<0.01), and had a greater prevalence of ischemic heart disease (17 vs. 22.0%; P<0.05), heart failure (26.9 vs. 35.5%; P<.002), peripheral vascular disease (12.6 vs. 17.4%; P<.02), arterial hypertension (54.8 vs. 65.6%; P<.001), diabetes mellitus (29.4 vs. 37%; P<.02) and renal failure (6.5 vs. 16.8%; P<.0001).

CONCLUSIONS

This study confirms the elevated prevalence of associated diseases in patients with COPD who are admitted to the Spanish Internal Medicine Services and the increase of comorbidities.

Nine steps towards a better water meter management

The paper provides a comprehensive perspective of the critical aspects to be taken into account when planning the long-term management of water meters in a utility. In order to facilitate their quick understanding and practical implementation, they have been structured into nine steps. Ranging from an initial audit up to the final periodic meter replacement planning, these steps cover three aspects of the problem - field work, laboratory work and management tasks; and each one is developed in detail paying attention to the particular data needed and noting the practical outcome it will yield.

Medical comorbidity in recurrent versus first-episode depressive patients

OBJECTIVE

This study compares the comorbidity of affective disorders and medical diseases in primary care patients with either a first or recurrent depressive episode.

METHOD

A cross-sectional epidemiological study in primary care centres in Spain was designed. A total of 10,257 primary care patients suffering a DSM-IV major depressive episode (MDD) were analysed. Depression was assessed using the Montgomery-Asberg Depression Rating Scale (MADRS), and World Health Organization (WHO) medical diagnoses were provided by the patient's general practitioner according to medical records revised on the basis of radiology or laboratory test data.

RESULTS

A total of 88.6% of recurrent patients and 71.1% of first-episode depressive patients reported a medical condition (aOR = 2.61, CI = 2.31-2.93). All medical conditions were more prevalent in the recurrent group than in first-episode group, and with the exception of myocardial infarction, psoriasis and migraine, all other crude ORs showed statistically significant differences between first- and recurrent episodes patients after adjusting for gender, age, education, socioeconomic status and body mass index (BMI).

CONCLUSION

Recurrent depression is associated with a decrement in health that is significantly greater than in first-episode depression. Special attention needs to be paid to the physical health in the middle- and long-term management of patients with affective disorders.

[Study of the comorbidities in hospitalized patients due to decompensated chronic obstructive pulmonary disease attended in the Internal Medicine Services. ECCO Study]

OBJECTIVE

Evaluate comorbidity in patients hospitalized due to COPD in the Internal Medicine services.

METHODS

An observational, prospective and multicenter study. The Charlson index and a specific questionnaire were used.

RESULTS

A total of 398 patients, 353 men (89%), with mean age of 73.7 years (8.9) and mean FEV(1) of 43.2% (12.5), were included. The most frequent comorbidities were: arterial hypertension (55%), arrhythmias (27%) and diabetes mellitus (26%). A total of 27% suffered heart failure, 17% coronary disease and 9% previous myocardial infarction. The number of associated chronic diseases was 3.6 (1,8). Score on Charlson index was 2.72 (2).

CONCLUSIONS

The patients hospitalized due to decompensated COPD had an elevated comorbidity.

Recent trends in COPD prevalence in Spain: a repeated cross-sectional survey 1997-2007

We aimed to describe changes in the prevalence of chronic obstructive pulmonary disease (COPD) in Spain by means of a repeated cross-sectional design comparing two population-based studies conducted 10 yrs apart. We compared participants from IBERPOC (Estudio epidemiológico de EPOC en España) (n = 4,030), conducted in 1997, with those of EPI-SCAN (Epidemiologic Study of COPD in Spain) (n = 3,802), conducted in 2007. Poorly reversible airflow obstruction compatible with COPD was defined according to the old European Respiratory Society definitions. COPD prevalence in the population between 40 to 69 yrs of age dropped from 9.1% (95% CI 8.1-10.2%) in 1997 to 4.5% (95% CI 2.4-6.6%), a 50.4% decline. The distribution of COPD prevalence by severity also changed from 38.3% mild, 39.7% moderate and 22.0% severe in 1997, to 85.6% mild, 13.0% moderate and 1.4% severe in 2007, and in the 40-69 yr EPI-SCAN sub-sample to 84.3% mild, 15.0% moderate and 0.7% severe. Overall, underdiagnosis was reduced from 78% to 73% (not a significant difference) and undertreatment from 81% to 54% (p<0.05) within this 10-yr frame. The finding of a substantial reduction in the prevalence of COPD in Spain is unexpected, as were the observed changes in the severity distribution, and highlights the difficulties in comparisons between repeated cross-sectional surveys of spirometry in the population.

Asthma insights and reality in the Gulf and the near East

BACKGROUND

Data on the burden of asthma and the quality of asthma control in the Gulf and Near East (GNE) are scarce.

OBJECTIVE

To determine how closely asthma management guidelines are being followed in the GNE.

METHODS

The Asthma Insights and Reality in the GNE (AIRGNE) survey is based on information from 1000 patients with asthma in five countries: Jordan, Kuwait, Lebanon, Oman and the United Arab Emirates (UAE).

RESULTS

Daytime asthma symptoms were reported by 68% of respondents, and 51% reported being woken up by asthma in the preceding 4 weeks. Use of health services in the last 12 months was high, with 23% having been hospitalised and 52% having attended the emergency department. Absence from school and work in the past year was reported by 52% of children and 30% of adults. The highest school absence was observed in Jordan and Lebanon (both 69%), and Jordan had the highest rate of absence from work among adults (46%). The use of peak expiratory flow was very low, and only 17% owned a meter. Overall, 66% of participants had never undergone a lung function test.

CONCLUSION

Current levels of asthma control in the GNE fall far short of the goals specified in guidelines for asthma management.

Prevalence of COPD in Spain: impact of undiagnosed COPD on quality of life and daily life activities

AIMS

This study aimed to determine the prevalence of chronic obstructive pulmonary disease (COPD) in Spain and identify the level of undiagnosed disease and its impact on health-related quality of life (HRQL) and activities of daily living (ADL).

METHODS

A population-based sample of 4274 adults aged 40-80 years was surveyed. They were invited to answer a questionnaire and undergo prebrochodilator and postbronchodilator spirometry. COPD was defined as a postbronchodilator FEV(1)/FVC (forced expiratory volume in 1 s/forced vital capacity) ratio of <0.70.

RESULTS

For 3802 participants with good-quality postbronchodilator spirometry, the overall prevalence of COPD was 10.2% (95% CI 9.2% to 11.1%) and was higher in men (15.1%) than in women (5.6%). The prevalence of COPD stage II or higher was 4.4% (95%CI; 3.8%-5.1%). The prevalence of COPD increased with age and with cigarette smoking and was higher in those with a low educational level. A previous diagnosis of COPD was reported by only 27% of those with COPD. Diagnosed patients had more severe disease, higher cumulative tobacco consumption and more severely impaired HRQL compared with undiagnosed subjects. However, even patients with undiagnosed COPD stage I+ already showed impairment in HRQL and in some aspects of ADL compared with participants without COPD.

CONCLUSIONS

The prevalence of COPD in individuals between 40 and 80 years of age in Spain is 10.2% and increases with age, tobacco consumption and lower educational levels. The rate of diagnosised COPD is very high and undiagnosed individuals with COPD already have a significant impairment in HRQL and ADL.

[The EPI-SCAN survey to assess the prevalence of chronic obstructive pulmonary disease in Spanish 40-to-80-year-olds: protocol summary]

BACKGROUND AND OBJECTIVES

Chronic obstructive pulmonary disease (COPD) causes considerable morbidity and mortality in Spain. The 1997 IBERPOC study, applying the old criteria of the European Respiratory Society, reported a COPD prevalence of 9.1% in the adult population of Spain. The Epidemiologic Study of COPD in Spain (EPI-SCAN) aims to determine the current prevalence of COPD in residents of Spain aged 40-80 years and to estimate changes over the past 10 years. Secondary objectives are, among others, to describe the current prevalence of smoking and changes in COPD prevalence relative to previous studies; to describe treatments received by patients, quality of life, and the BODE index (body mass index, obstruction of airflow, dyspnea, and exercise tolerance); and to measure inflammatory markers in blood and exhaled-breath condensate.

PATIENTS AND METHODS

EPI-SCAN is a population-based, cross-sectional epidemiologic study targeting the general population of Spain aged between 40 and 80 years. Participating centers were located in Barcelona, Burgos, Cordoba, Huesca, Madrid, Oviedo, Seville, Valencia, Vic, and Vigo. All subjects filled in an extensive questionnaire to collect social, demographic, and clinical information. Slow and forced spirometry tests before and after a bronchodilator test were also undertaken. Additionally, selected subjects performed a 6-minute walk test and answered generic and specific quality-of-life questionnaires, as well as an activities-of-daily-living questionnaire. Exhaled-breath condensate and blood samples were also collected from these subjects for measurement of inflammatory and other biomarkers.

Proportional classifications of COPD phenotypes

BACKGROUND

Chronic obstructive pulmonary disease (COPD) encompasses a group of disorders characterised by the presence of incompletely reversible airflow obstruction with overlapping subsets of different phenotypes including chronic bronchitis, emphysema or asthma. The aim of this study was to determine the proportion of adult subjects aged >50 years within each phenotypic subgroup of COPD, defined as a post-bronchodilator ratio of forced expiratory volume in 1 s/forced vital capacity (FEV(1)/FVC) <0.7, in accordance with current international guidelines.

METHODS

Adults aged >50 years derived from a random population-based survey undertook detailed questionnaires, pulmonary function tests and chest CT scans. The proportion of subjects in each of 16 distinct phenotypes was determined based on combinations of chronic bronchitis, emphysema and asthma, with and without incompletely reversible airflow obstruction defined by a post-bronchodilator FEV(1)/FVC ratio of 0.7.

RESULTS

A total of 469 subjects completed the investigative modules, 96 of whom (20.5%) had COPD. Diagrams were constructed to demonstrate the relative proportions of the phenotypic subgroups in subjects with and without COPD. 18/96 subjects with COPD (19%) had the classical phenotypes of chronic bronchitis and/or emphysema but no asthma; asthma was the predominant COPD phenotype, being present in 53/96 (55%). When COPD was defined as a post-bronchodilator FEV(1)/FVC less than the lower limit of normal, there were one-third fewer subjects with COPD and a smaller proportion without a defined emphysema, chronic bronchitis or asthma phenotype.

CONCLUSION

This study provides proportional classifications of the phenotypic subgroups of COPD which can be used as the basis for further research into the pathogenesis and treatment of this heterogeneous disorder.

Insulin resistance and daytime sleepiness in patients with sleep apnoea

BACKGROUND

Excessive daytime sleepiness (EDS), obesity and insulin resistance (IR) occur frequently in patients with obstructive sleep apnoea syndrome (OSAS). We hypothesised that in these patients, EDS is a marker of IR, independent of obesity.

METHODS

We studied 44 patients with OSAS (22 with and 22 without EDS) matched for age (+/-5 years), body mass index (BMI +/-3 kg/m(2)) and severity of OSAS (as determined by the apnoea-hypopnoea index (AHI)), and 23 healthy controls. Patients (n = 35) were re-examined after 3 months of effective therapy with continuous positive airway pressure (CPAP). EDS was assessed by both subjective (Epworth Sleepiness Scale) and objective (Multiple Sleep Latency Test) methods. IR was determined by the HOMA index. Serum levels of glucose, triglycerides, cholesterol, cortisol, insulin, thyrotropin, growth hormone and insulin-like growth factor I (IGF-I) were also determined.

RESULTS

Despite the fact that age, BMI and AHI were similar, patients with EDS had higher plasma levels of glucose (p<0.05) and insulin (p<0.01), as well as evidence of IR (p<0.01) compared with patients without EDS or healthy controls. CPAP treatment reduced cholesterol, insulin and the HOMA index and increased IGF-1 levels in patients with EDS, but did not modify any of these variables in patients without EDS.

CONCLUSION

EDS in OSAS is associated with IR, independent of obesity. Hence EDS may be a useful clinical marker to identify patients with OSAS at risk of metabolic syndrome.

beta3-Adrenergic receptor Trp64Arg polymorphism and increased body mass index in sleep apnoea

Obesity is an important risk factor for obstructive sleep apnoea syndrome (OSAS), insulin resistance and cardiovascular disease. The substitution of tryptophan 64 with arginine (Trp64Arg) polymorphism (Arg variant) of the beta(3)-adrenergic receptor (ADRB3) has been associated with obesity. In this study, the prevalence of the Trp64Arg ADRB3 polymorphism in a large group of patients with OSAS and its association with body mass index (BMI), insulin resistance and hypertension were evaluated. ADRB3 genotype was determined in 387 patients with OSAS and 137 healthy subjects recruited from three Spanish tertiary hospitals. The distributions of the ADRB3 genotypes were similar in OSAS and controls, and, in a multivariate model, the risk of OSAS was not associated with the presence of the Arg variant of the ADRB3 gene. However, BMI was higher in those patients with OSAS who carried this genetic variant than in those with the Trp variant. Furthermore, a linear trend for higher BMI was found in those with the Arg variant (56, 75 and 100% for Trp/Trp, Trp/Arg and Arg/Arg, respectively). Insulin resistance, blood pressures and serum levels of lipids and glucose were not associated with the presence of the Arg variant of the ADRB3 gene. The presence of the arginine 64 allele of the beta(3)-adrenergic receptor gene does not increase the risk of obstructive sleep apnoea syndrome, but is associated with the development of obesity in those patients who suffer obstructive sleep apnoea syndrome.

Mortality in COPD: Role of comorbidities

Chronic obstructive pulmonary disease (COPD) represents an increasing burden throughout the world. COPD-related mortality is probably underestimated because of the difficulties associated with identifying the precise cause of death. Respiratory failure is considered the major cause of death in advanced COPD. Comorbidities such as cardiovascular disease and lung cancer are also major causes and, in mild-to-moderate COPD, are the leading causes of mortality. The links between COPD and these conditions are not fully understood. However, a link through the inflammation pathway has been suggested, as persistent low-grade pulmonary and systemic inflammation, both known risk factors for cardiovascular disease and cancer, are present in COPD independent of cigarette smoking. Lung-specific measurements, such as forced expiratory volume in one second (FEV(1)), predict mortality in COPD and in the general population. However, composite tools, such as health-status measurements (e.g. St George's Respiratory Questionnaire) and the BODE index, which incorporates Body mass index, lung function (airflow Obstruction), Dyspnoea and Exercise capacity, predict mortality better than FEV(1) alone. These multidimensional tools may be more valuable because, unlike predictive approaches based on single parameters, they can reflect the range of comorbidities and the complexity of underlying mechanisms associated with COPD. The current paper reviews the role of comorbidities in chronic obstructive pulmonary disease mortality, the putative underlying pathogenic link between chronic obstructive pulmonary disease and comorbid conditions (i.e. inflammation), and the tools used to predict chronic obstructive pulmonary disease mortality.