Reliability of blood eosinophil count in steady-state bronchiectasis

RATIONALE

The baseline value of eosinophils in peripheral blood (BEC) has been associated with different degrees of severity, prognosis and response to treatment in patients with bronchiectasis. It is not known, however, if this basal value remains constant over time.

OBJECTIVES

The aim of this study was to assess whether the BEC remains stable in the long term in patients with bronchiectasis.

METHODS AND MEASUREMENTS

Patients from the RIBRON registry of bronchiectasis diagnosed by computed tomography with at least 2 BEC measurements one year apart were included in the study. Patients with asthma and those taking anti-eosinophilic drugs were excluded. Reliability was assessed using the intra-class correlation coefficient (ICC). A patient with a BEC of at least 300 cells/uL or less than 100 cells/uL was considered eosinophilic or eosinopenic, respectively. Group changes over time were also calculated.

MAIN RESULTS

Seven hundred and thirteen patients were finally included, with a mean age of 66.5 (13.2) years (65.8 % women). A total of 2701 BEC measurements were performed, with a median number of measurements per patient of 4 (IQR: 2-5) separated by a median of 12.1 (IQR: 10.5-14.3) months between two consecutive measurements. The ICC was good (>0.75) when calculated between two consecutive measurements (approximately one year apart) but had dropped significantly by the time of the next annual measurements. Similarly, the change from an eosinophilic or eosinopenic patient to a non-eosinophilic or non-eosinopenic patient, respectively, was less than 30 % during the first year with respect to the baseline value but was close to 50 % in later measurements.

CONCLUSIONS

Given the significant changes observed in the baseline value of the BEC over time, its monitoring is necessary in patients with bronchiectasis in order to more reliably assess its usefulness.

The role of precision medicine in bronchiectasis: Emerging data and clinical implications

INTRODUCTION

Bronchiectasis is a very heterogeneous disease. This heterogeneity has several consequences: severity cannot be measured by a single variable, so multidimensional scores have been developed to capture it more broadly. Some groups of patients with similar clinical characteristics or prognoses (clinical phenotypes), and even similar inflammatory profiles (endotypes), have been identified, and these have been shown to require a more specific treatment.

AREAS COVERED

We comment on this "stratified" model of medicine as an intermediate step towards the application of the usual concepts on which precision medicine is based (such as cellular, molecular or genetic biomarkers, treatable traits and individual clinical fingerprinting), whereby each subject presents certain specific characteristics and receives individualized treatment.

EXPERT OPINION

True precision or personalized medicine is based on concepts that have not yet been fully achieved in bronchiectasis, although some authors are already beginning to adapt them to this disease in terms of pulmonary and extrapulmonary aetiologies, clinical fingerprinting (specific to each individual), cellular biomarkers such as neutrophils and eosinophils (in peripheral blood) and molecular biomarkers such as neutrophil elastase. In therapeutic terms, the future is promising, and some molecules with significant antibiotic and anti-inflammatory properties are being developed.

Treatment with CPAP in Elderly Patients with Obstructive Sleep Apnoea

The population pyramid is changing as a result of the ever-increasing life expectancy, which makes it crucial to acquire an in-depth understanding of the diseases that most often affect the elderly. Obstructive sleep apnoea (OSA) affects 15%-20% of the population aged over 65 years. Despite this prevalence, there have been very few specific studies on the management of OSA in this age group, even though over 60% of the patients aged over 65-70 years who attend sleep units with suspicion of OSA receive treatment with continuous positive airway pressure (CPAP), on the basis of an extrapolation of the positive results achieved by CPAP in clinical trials involving middle-aged males. However, the latter's form of presentation, evolution and, probably, prognosis comparing with OSA are not the same as those of elderly patients. Recent clinical trials performed on an exclusive series of elderly patients have shed light on the possible role of CPAP treatment in elderly patients with OSA, but there are still many questions that need to be answered. The physiological increase in the number of sleep-related disorders with the passing of years, and the lack of validated diagnostic and therapeutic tools for this age group are probably the greatest obstacles to define, diagnose and treat OSA in the elderly.

Bronchiectasis: A Complex, Heterogeneous Disease

Most areas of respiratory medicine continue to use an Oslerian approach, based on signs and symptoms, in which the disease is the center of all activity. However, this paradigm is changing. Now that lung diseases have been recognized as heterogeneous and complex, we are moving towards more personalized, precise, patient-oriented medicine. The aim of this review was to define the current state of the knowledge on bronchiectasis, or, more accurately, the bronchiectasis syndrome, as a multidimensional, systemic, heterogeneous, complex disease. We explore the advances that have already been made, and above all the many steps that are still to be taken. We also propose some tools which might facilitate the application of these concepts in clinical practice, and help us continue our journey towards a more holistic view of this disease.

Prevalence and factors associated with nontuberculous mycobacteria in non-cystic fibrosis bronchiectasis: a multicenter observational study

Background

Data on the prevalence of and factors associated with nontuberculous mycobacteria (NTM) in patients with non–cystic fibrosis (CF) bronchiectasis are limited. Our aim was to determine the prevalence and factors associated with isolation of NTM in this population.

Methods

We performed a multicenter observational study of historical cohorts comprising consecutive patients with non-CF bronchiectasis and at least 2 sputum samples cultured for mycobacteria over a period of 5 years.

Results

The study population included 218 adult patients (61.9 % women) with a mean (SD) age of 55.7 (16) years and a mean (SD) of 5.1 (3.3) cultures/patient. NTM was isolated from sputum in 18 patients (8.3 %). Of these, 5 patients (28 %) met the American Thoracic Society criteria for NTM disease. Mycobacterium avium complex was the most frequently isolated microorganism (9 patients, 4.1 %). The variables independently associated with isolation of NTM were FVC ≥ 75 % predicted (OR, 4.84; 95 % CI 1.47 to 15.9; p < 0.05), age ≥ 50 years (OR, 4.74; 95 % CI 1.25 to 17.97; p < 0.05), and body mass index (BMI) ≤ 23 kg/m² (OR, 2.97; 95 % CI 1.03-8.58; p < 0.05). Patients with these three characteristics had a 40 % probability of having at least one isolation of NMT.

Conclusions

A significant number of patients with non-CF bronchiectasis are positive for the isolation of NTM. M. avium complex is the most frequently isolated mycobacteria. FVC ≥ 75 % predicted, age ≥ 50 years, and a BMI ≤ 23 kg/m² were independently associated with the presence of NTM in patients with non-CF bronchiectasis.

[Hot topics respiratory infections]

Revisión crítica de los artículos sobre infecciones respiratorias publicados en el último trimestre de 2008 y el presente año. En los pacientes con bronquiectasias destacan artículos que estudian su calidad de vida, así como los que analizan la disminución del número de exacerbaciones por el efecto inmunomodulador de la utilización de macrólidos a dosis bajas en estos pacientes. En el diagnóstico de la tuberculosis, son especialmente relevantes los trabajos sobre la aplicación del interferón gamma, mientras que en el tratamiento de esta afección destacan los artículos que estudian innovaciones terapéuticas en el tratamiento de la TB-MDR y TB-XDR o -TDR. En cuanto a las publicaciones referidas a las neumonías, son llamativas las que analizan la evolución de las neumonías adquiridas en la comunidad (NAC) en pacientes afectados de enfermedad pulmonar obstructiva crónica. Asimismo, cobran especial relevancia los estudios iniciales epidemiológicos y clínicos de la pandemia por gripe A (H1N1). También son de interés la valoración de las escalas pronósticas como predictoras de soporte ventilatorio y/o del uso de aminas presoras, así como el uso de los marcadores biológicos como complemento del valor predictivo de las citadas escalas pronósticas. Siguen teniendo gran interés los estudios etiológicos y clínicos de las neumonías asociadas al sistema de salud y sus posibles diferencias respecto a las NAC. En cuanto al tratamiento de las neumonías, son interesantes los análisis de la probable capacidad moduladora de la inflamación de diversos fármacos.

Continuous positive airway pressure treatment reduces mortality in patients with ischemic stroke and obstructive sleep apnea: a 5-year follow-up study

RATIONALE

Obstructive sleep apnea (OSA) is an independent risk factor for stroke, but little is known about the role of continuous positive airway pressure (CPAP) on mortality in patients with stroke.

OBJECTIVES

To analyze the independent impact of long-term CPAP treatment on mortality in patients with ischemic stroke.

METHODS

Prospective observational study in 166 patients with ischemic stroke. Sleep study was performed in all of them and CPAP treatment was offered in the case of moderate to severe cases. Patients were followed-up for 5 years to analyze the risk of mortality.

MEASUREMENTS AND MAIN RESULTS

Of 223 patients consecutively admitted for stroke, a sleep study was performed on 166 of them (2 mo after the acute event). Thirty-one had an apnea-hypopnea index (AHI) of less than 10; 39 had an AHI between 10 and 19, and 96 had an AHI of 20 or greater. CPAP treatment was offered when AHI was 20 or greater. Patients were followed up in our outpatient clinic at 1, 3, and 6 months, and for every 6 months thereafter for 5 years (prospective observational study). Mortality data were recorded from our computer database and official death certificates. The mean age of subjects was 73.3 +/- 11 years (59% males), and the mean AHI was 26 (for all patients with a predominance of obstructive events). Patients with an AHI of 20 or greater who did not tolerate CPAP (n = 68) showed an increase adjusted risk of mortality (hazards ratio [HR], 2.69; 95% confidence interval [CI], 1.32-5.61) compared with patients with an AHI of less than 20 (n = 70), and an increased adjusted risk of mortality (HR, 1.58; 95% CI, 1.01-2.49; P = 0.04) compared with patients with moderate to severe OSA who tolerated CPAP (n = 28). There were no differences in mortality among patients without OSA, patients with mild disease, and patients who tolerated CPAP.

CONCLUSIONS

Our results suggest that long-term CPAP treatment in moderate to severe OSA and ischemic stroke is associated with a reduction in excess risk of mortality.

[Efficacy of a training program on sleep apnea-hypopnea syndrome aimed at primary care physicians]

OBJECTIVE

The level of clinical suspicion of sleep apnea-hypopnea syndrome (SAHS) among primary care physicians is low. The aim of this study was to analyze the impact of a primary care training program on the quality and quantity of referrals made due to suspected SAHS.

MATERIAL AND METHODS

A group of 16 primary care physicians were offered the option of participating in a training program consisting of 2 talks-workshops, the provision of up-to-date information on SAHS and a form for making referrals according to an established protocol, and the opportunity to contact the sleep department at our hospital directly. Twenty-one primary care physicians who did not receive training served as the control group. We gathered data on the quantity and quality of referrals made by both groups for the period January through June 2005 and 2006, and recorded the number of both SAHS diagnoses made and patients prescribed treatment with continuous positive airway pressure. Data were analyzed in function of the primary care population assigned to each group.

RESULTS

The training program was completed by 81.3% of the physicians. The number of referrals made by the training group increased 2.38-fold after the program (intergroup comparison, P=.0001). There was also a 2.36-fold increase in the percentage of cases of SAHS detected in the population (P=.0008), a 1.85-fold increase in the percentage of serious cases detected (P=.001), and a 2-fold increase in the number of patients prescribed continuous positive airway pressure (P=.009). Agreement between the data gathered by the physicians and the sleep specialist was significantly higher in the training group for all the items studied.

CONCLUSIONS

The implementation of a training program on SAHS aimed at primary care physicians improved both the quantity and quality of referrals made due to suspected SAHS.

[The association between bronchiectasis, systemic inflammation, and tumor necrosis factor alpha]

OBJECTIVE

The relationship between systemic inflammation and different measures of bronchiectasis severity has not been described. The objective of this study was to analyze the relationship between plasma concentrations of tumor necrosis factor alpha (TNF-alpha), as a marker of systemic inflammation, and some commonly used criteria for quantifying bronchiectasis severity in clinically stable patients whose disease was not caused by cystic fibrosis.

PATIENTS AND METHODS

Sixty-eight clinically stable patients with bronchiectasis and 19 age- and sex-matched healthy control subjects were included in the study. Data on disease history, symptoms, severity, functional variables, sputum volume, and microbiological cultures, laboratory findings, and other indicators of disease course were collected. Plasma concentrations of TNF-alpha were measured using high-resolution enzyme-linked immunoabsorbent assay.

RESULTS

Plasma concentrations of TNF-alpha were higher in patients than controls (8.28 vs 5.67 pg/mL; P=.001). This observation correlated with other markers of systemic inflammation such as erythrocyte sedimentation rate (r=0.42; P=.001), C-reactive protein (rho=0.45; P=.001), and percentage of peripheral blood neutrophils (rho=0.45; P=.001). Patients with high plasma concentrations of TNF-alpha (>8.1 pg/dL) had more severe disease (5.19 vs 3.21; P=.001), were more likely to have respiratory failure (37.5% vs 8.3%; P=.003), and a higher rate of Pseudomonas aeruginosa colonization (34.3% vs 8.3%; P=.008).

CONCLUSIONS

High plasma concentrations of TNF-alpha were associated with several criteria usually used to assess severity of bronchiectasis in clinically stable patients with disease not caused by cystic fibrosis.

Factors associated with lung function decline in adult patients with stable non-cystic fibrosis bronchiectasis

BACKGROUND

Bronchiectasis remains a major public health problem, but factors influencing its natural history are not well characterized. The objective of our study was to explore modifiable and nonmodifiable factors associated with lung function decline in a clinical cohort of patients with stable non-cystic fibrosis (CF) bronchiectasis.

METHODS

Seventy-six stable adult patients (mean age, 69.9 years; 48.7% men) with bronchiectasis were included. The diagnosis of bronchiectasis was established in all cases by high-resolution CT scanning. Baseline data were collected on clinical history, symptoms, disease extension, treatment, sputum volume, microbiological aspects, laboratory findings, and exacerbations. All patients were invited to attend the clinic every 6 months for 24 months to conduct full spirometry and microbiological analysis of sputum, and to report the number of exacerbations.

RESULTS

Overall, the group experienced a rate of decline of lung function (FEV1) of 52.7 mL per year. Independent factors associated with an accelerated decline of lung function were chronic colonization with Pseudomonas aeruginosa (PA) [odds ratio (OR), 30.4; 95% confidence interval (CI), 3.8 to 39.4; p=0.005], more frequent severe exacerbations (OR, 6.9; 95% CI, 2.3 to 10.5; p=0.014), and more systemic inflammation (OR, 3.1; 95% CI, 1.9 to 8.9; p=0.023). Regrettably, none of the long-term treatment strategies evaluated, including the use of long-acting inhaled bronchodilators, inhaled or oral steroids, oxygen therapy, secretion clearance maneuvers, or antibiotics had a significant effect on FEV1 decline.

CONCLUSION

Chronic colonization by PA, severe exacerbations, and systemic inflammation are associated with disease progression in non-CF bronchiectasis.

Dissociation of lung function, dyspnea ratings and pulmonary extension in bronchiectasis

Bronchiectasis is a heterogeneous disease in terms of its clinical and functional presentation. Some isolated parameters have been used to assess the severity of bronchiectasis or its response to treatment. A study was undertaken to evaluate whether lung function, dyspnea and extension of the disease are separate entities in the impact of bronchiectasis upon patients using factor analysis. Patients with bronchiectasis diagnosed by high-resolution computed tomography (HRCT) and airflow obstruction defined by FEV1/FVC<70% were included. Data were collected relating to clinical history, three different clinical ratings of dyspnea (Medical Research Council (MRC), Borg scale and Basal Dyspnea Index), the extent of bronchiectasis and functional variables. A total of 81 patients (mean age (SD): 69.5 (8.7)) years were included. The degree of dyspnea (MRC) was 1.9 (0.8). Mean FEV1 was 1301 ml (56.9% pred.). Four factors were found that accounted for 84.1% of the total data variance. Factor 1 (45.6% of the data variance) included the three measurements of dyspnea. Factor 2 (16% variance) comprised airflow obstruction parameters (FEV1, FEV1/FVC and PEF). Factor 3 (13.8% variance) included RV/TLC and RV (lung hyperinflation). Factor 4 (8.6% variance) included bronchiectasis extent. Dyspnea was more closely correlated with lung hyperinflation (r:0.33-0.54) than with airflow obstruction parameters (r:0.17-0.26).

CONCLUSIONS

Airflow obstruction, dyspnea, lung hyperinflation and the lung extent of the bronchiectasis are four independent entities in the impact of bronchiectasis upon patients.

[Bronchiectasis in the elderly. Study of serum levels of immunoglobulin G subclasses]

BACKGROUND AND OBJECTIVE

To analyze the serum levels of immunoglobulin G (IgG) subclasses in a broad range of elderly patients with bronchiectasis.

PATIENTS AND METHOD

Data were collected from all patients who had a high-resolution chest computerized axial tomography diagnosis of bronchiectasis in our center. We gathered data related to case history, respiratory symptoms, forced spirometry, general laboratory tests, immunoglobulin concentration (including IgG subclasses), Mantoux test, sputum culture and staining, paranasal sinus X-rays/computerized axial tomography, and a specific etiologic evaluation based on the available clinical evidence.

RESULTS

A total of 128 patients were included -mean age (standard deviation): 71.6 (5.1) years; range: 65-88; 44.5% males- and 20.3% of them had chronic sputum colonization with Pseudomonas aeruginosa. 28.1% cases had a post-infectious nature and in 40.6% the etiology was unknown. Sixteen patients (12.5%) had decreased levels of at least one of the sIgG compared to normal values. The most frequent deficiency corresponded to IgG2 levels. These subjects showed a characteristic profile of bronchiectasis with an increased lung extension of the disease (p = 0.02); greater presence of cylindrical and diffuse bronchiectasis (p = 0.02 and 0.01, respectively), greater percentage of an unknown etiology (p = 0.004); greater presence of paranasal sinus X-ray abnormalities (p = 0.004) and increased number of past repeated upper airway infections (p = 0.03).

CONCLUSIONS

Decreased serum levels of IgG subclasses might be associated with a characteristic profile of bronchiectasis in elderly patients in whom other etiologies have been ruled out.

[Effectiveness of a specific program for patients with chronic obstructive pulmonary disease and frequent exacerbations]

OBJECTIVE

Patients with chronic obstructive pulmonary disease (COPD) and a history of frequent exacerbations are a target population of particular interest from both a clinical and an economic standpoint. The objective of this study was to evaluate the effectiveness of a program designed specifically to manage patients in this subgroup.

PATIENTS AND METHODS

This was a 1-year randomized controlled trial designed to compare the effectiveness of a specific program (SP) with that of conventional management (CM) in a group of patients with a high frequency of exacerbations (3 or more per year). Within-group and between-group comparisons were carried out for a number of variables related to the patients medical care, dyspnea, health-related quality of life (HRQL), inhalation technique, and pulmonary function.

RESULTS

A total of 26 patients were enrolled in the study (all men). The mean (SD) age was 73 (8) years, and mean forced expiratory volume in 1 second (FEV1) expressed as a percentage of the reference value was 43% (15%). Exacerbations requiring hospital care (emergency department visits and/or admission) decreased in both groups: by 24.4% (P not significant) in the CM group and 44.1% (P=.061) in the SP group. Hospital admissions decreased 73.3% in the SP group and increased 22% in the CM group (P< .001). While length of hospital stay decreased 77.3% in the SP group, this figure almost doubled in the CM group (P=.014). Dyspnea, HRQL, and inhalation technique improved in both groups. FEV1 fell by 46 mL/year in the CM group and increased 10 mL/year in the SP group (P not significant).

CONCLUSIONS

The use of a simple program to manage selected patients with a history of frequent exacerbations produces a significant reduction in the number of hospital admissions, an improvement in HRQL, and may improve prognosis.

Positive effect of CPAP treatment on the control of difficult-to-treat hypertension

The aim of the present study was to analyse the role of continuous positive airway pressure (CPAP) treatment in patients with difficult-to-control hypertension (DC-HT) and sleep apnoea. An Autoset (ResMed, Sydney, Australia) study was performed in 60 patients diagnosed with DC-HT based on two 24-h ambulatory blood pressure monitorisation (ABPM) studies. CPAP was offered to patients with an apnoea/hypopnoea index (AHI) > or =15 events.h(-1). After 3 months of treatment, repeat ABPM was performed to evaluate the effect of CPAP upon the blood pressure values. A total of 39 (65%) patients received CPAP treatment, but only 33 completed the study. The mean+/-sd systolic and diastolic blood pressures (SBP and DBP, respectively) were 154.8+/-14 and 90+/-8.8 mmHg. Patients had a mean+/-sd AHI of 37.7+/-18.2 events.h(-1). Only three patients presented a dipper nocturnal pressure pattern. CPAP treatment significantly reduced SBP (-5.2 mmHg), and particularly the nocturnal values (-6.1 mmHg), but not DBP. Considering only those patients who tolerated CPAP, the decrease in SBP was greater (-7.3 mmHg). Furthermore, CPAP treatment significantly increased the percentage of patients who recovered the dipper pattern (three (9.1%) out of 33 versus 12 (36.4%) out of 33). Continuous positive airway pressure treatment significantly reduces systolic blood pressure, particularly at night, and normalises the nocturnal pressure pattern in patients with difficult-to-control hypertension and sleep apnoea.

Improvement in nocturnal disordered breathing after first-ever ischemic stroke: role of dysphagia

STUDY OBJECTIVE

The aim of this study was to analyze the role of dysphagia as a model of pharyngeal muscle dysfunction in the time course of nocturnal disordered breathing (NDB) in patients who experienced a first-ever ischemic stroke.

DESIGN

Prospective study.

PATIENTS AND INTERVENTIONS

Fifty-nine consecutive patients (mean age, 73.2 years; SD, 12.8 years) were studied. Clinical sleep and neurologic data and vascular risk factors were recorded. Two nocturnal studies using a portable autotitration device (AutoSet Portable Plus II system; ResMed; Sydney, NSW, Australia) were performed in both the acute phase (mean duration, 1.23 days; SD, 0.7 day) and the stable phase (mean duration 65.9 days; SD, 12.5 days) of the neurologic event in all patients.

RESULTS

The mean total apnea-hypopnea index (AHI) measured with the autotitration device in the acute phase was 34.9 (SD, 25.2) vs 20.1 (SD, 21.7) in the stable phase, both with predominance of obstructive apnea. Patients with dysphagia (n = 30) showed the largest number of obstructive apneic episodes (OAIs) in the acute phase (AHI, 40 episodes; OAI, 30.4 episodes), with a significant reduction in this type of apnea during the stable phase of stroke (AHI, 24.7 episodes; OAI, 17.7 episodes), coinciding with the recovery of pharyngeal muscle function. In contrast, nondysphagic patients (n = 29) showed no significant changes in NDB from the acute to the stable phase of stroke. Logistic regression analysis found dysphagia to be the best independent predictor of AHI reduction of > 50% from baseline (odds ratio, 13.4; 95% confidence interval, 3.3 to 39.6; p = 0.001).

CONCLUSION

The present study shows significant improvement in the number obstructive apneic events occurring in the stable phase of a first-ever ischemic stroke in patients with transient pharyngeal muscle alterations secondary to the neurologic lesion.

Sleep-Disordered Breathing in Patients With Difficult-to-Control Hypertension

OBJECTIVE

To analyze the relationship between sleep-disordered breathing and difficult-to-control arterial hyper-tension.

PATIENTS AND METHODS

Patients were considered to have difficult-to-control hypertension when mean systolic blood pressure was 125 mm Hg or higher and/or mean diastolic blood pressure was more than or equal to 80 mm Hg (as recorded during 2 24-hour ambulatory monitoring studies) despite the use of 3 or more antihypertensive drugs. Respiratory polygraphy using the AutoSet device (ResMed Corp, Sydney, Australia) was then performed to study sleep-disordered breathing in all patients.

RESULTS

Forty-nine patients with a mean (SD) age of 68.1 (9.1) years, mean systolic and diastolic pressures of 152.5 (13)/89.2 (8.5) mm Hg, and an average of 3.5 prescribed drugs were included in the study. The mean apnea-hypopnea index (AHI) was 26.2 (19.5) and events were predominantly obstructive. Patients with severe sleep apnea-hypopnea syndrome (SAHS) (AHI > or = 30; 40.8%) showed more uncontrolled daytime (P = .017) and nighttime (P = .033) systolic pressure than the rest, as well as higher daytime diastolic pressure (P = .035) and a greater consumption of drugs than those without severe SAHS (AHI < 10; 28.6%) (P = .041). The study population as a whole showed a significant correlation between blood pressure and obesity. There was a significant correlation (adjusted for age and sex) with AHI only in patients with SAHS. AHI was found to be the independent predictor with the greatest effect on blood pressure in these patients.

CONCLUSIONS

Prevalence of SAHS was very high in patients with difficult-to-control hypertension. In patients with SAHS, AHI was found to be the independent predictor with the greatest affect on arterial blood pressure.

Mid-Arm Muscle Area Is a Better Predictor of Mortality Than Body Mass Index in COPD

BACKGROUND

A low body mass index (BMI) has been shown to be an independent indicator of poor prognosis in patients with COPD. However, some studies suggest that muscle mass depletion (MD) is the main factor responsible for the negative effects attributable to malnutrition.

STUDY OBJECTIVE

To evaluate the prognostic influence of MD estimated from anthropometric parameters.

DESIGN AND MEASUREMENTS

Mortality was studied in a prospective cohort of 96 male patients with COPD (average age, 69 +/- 9 years; FEV1 percentage of predicted, 44 +/- 18% [ +/- SD]) followed up for 3 years, with an evaluation of the prognostic influence of the following anthropometric parameters: BMI, mid-arm muscle area (MAMA), and fat-free mass index. Other risk factors were also analyzed, such as age, comorbidity (Charlson index), basal dyspnea index, the St. George's Respiratory Questionnaire score, the number of hospital admissions in the year prior to nutritional evaluation, the number of hospital admissions in the year immediately after nutritional evaluation (Hpost), spirometry, and blood gases.

RESULTS

In the multivariate study, Pa(CO2) (p = 0.003; hazard ratio, 1.08), Hpost (p = 0.005, hazard ratio, 4.63), and a MAMA value less than or equal to percentile 25 of the reference value (p25) [p = 0.025; hazard ratio, 3.78] were found to be independent indicators of poor prognosis. Respiratory mortality after 12, 24, and 36 months in the patients with MAMA < or = p25 was 12.1%, 31.4%, and 39.2%, respectively, vs 5.9%, 7.9%, and 13% in the group of patients without MD (p = 0.006). In normal-weight or overweight patients, MAMA < or = p25 increased the risk of mortality 3.4-fold (p = 0.032).

CONCLUSIONS

MD is a better predictor of mortality than BMI in patients with COPD, fundamentally in normal-weight or overweight patients. The prognostic influence of MD can be estimated indirectly by determining the MAMA, an inexpensive, simple, and rapidly obtained anthropometric measure.

Continuous Positive Airway Pressure Treatment in Sleep Apnea Prevents New Vascular Events After Ischemic Stroke

STUDY OBJECTIVES

A study was made of the role of continuous positive airway pressure (CPAP) treatment in the prevention of new vascular events following ischemic stroke or transient ischemic attack.

DESIGN

Prospective study.

PATIENTS AND INTERVENTIONS

Demographic data, vascular risk factors, clinical manifestations associated to sleep apnea-hypopnea syndrome, and neurologic parameters were recorded in a group of patients presenting with acute ischemic stroke at least 2 months previously. A polygraphic study was carried out 2 months after the acute episode in all patients, with the prescription of CPAP in the event of an apnea-hypopnea index (AHI) > or = 20. Two groups were defined: patients who could tolerate CPAP (group 1), and patients who could not tolerate CPAP after 1 month of initial adaptation (group 2). Patients with an AHI < 20 were excluded. The incidence of new vascular events was evaluated throughout follow-up (18 months) in all patients, with an analysis of the role of CPAP in protecting the patients against such events.

RESULTS

Ninety-five patients were studied. Fifty-one patients (53.7%; mean age, 72.7 +/- 9.4 years [+/- SD]) presented with an AHI > or = 20, and 15 patients (29.4%) tolerated CPAP. The incidence of new vascular events was greater in group 2 (6.7%) vs group 1 (36.1%; long-rank, p = 0.03). Intolerance of CPAP increased the probability of a new vascular event fivefold (odds ratio, 5.09) adjusted for other vascular risk factors and neurologic indexes.

CONCLUSIONS

We concluded that CPAP treatment during 18 months in patients with an AHI > or = 20 afforded significant protection against new vascular events after ischemic stroke.

Quality-of-life determinants in patients with clinically stable bronchiectasis

STUDY OBJECTIVE

To determine the most important variables influencing health-related quality of life (HRQL) in patients with clinically stable bronchiectasis (SB).

DESIGN

Cross-sectional study.

PATIENTS AND INTERVENTIONS

A total of 86 patients (mean age, 69.5 years; SD, 8.9 years; 64% male) with SB were included. Data were collected on general patient characteristics, symptoms, laboratory findings, the extent of bronchiectasis, functional variables, medication in acute or stable phases, and the number of exacerbations. All patients completed the St. George Respiratory Questionnaire (SGRQ). Univariate and multivariate analyses were performed to identify the variables significantly influencing HRQL in these patients.

RESULTS

Different clinical parameters (sputum, dyspnea, cough, and wheezing), spirometric variables, and laboratory parameters (fibrinogen), as well as the extent of bronchiectasis, medication, and the number of exacerbations were significantly correlated to the total questionnaire score, although only dyspnea (r2 = 0.43, p < 0.0001), FEV1 (r2 = 0.33, p < 0.0001), and daily sputum production (r2 = 0.2, p < 0.004) were independently correlated to the total score, globally explaining 55% of the total score variability. Systemic steroid treatment of exacerbations (r2 = 0.17, p < 0.028) and the habitual presence of coughing (r2 = 0.22, p < 0.004) and wheezing (r2 = 0.16, p < 0.013) were in turn independently correlated to the activity and symptoms subscales, respectively.

CONCLUSION

Dyspnea, FEV1, and sputum production are the strongest conditioning factors of HRQL in patients with clinically SB.

Severe acute exacerbations and mortality in patients with chronic obstructive pulmonary disease

BACKGROUND

Patients with chronic obstructive pulmonary disease (COPD) often present with severe acute exacerbations requiring hospital treatment. However, little is known about the prognostic consequences of these exacerbations. A study was undertaken to investigate whether severe acute exacerbations of COPD exert a direct effect on mortality.

METHODS

Multivariate techniques were used to analyse the prognostic influence of acute exacerbations of COPD treated in hospital (visits to the emergency service and admissions), patient age, smoking, body mass index, co-morbidity, long term oxygen therapy, forced spirometric parameters, and arterial blood gas tensions in a prospective cohort of 304 men with COPD followed up for 5 years. The mean (SD) age of the patients was 71 (9) years and forced expiratory volume in 1 second was 46 (17)%.

RESULTS

Only older age (hazard ratio (HR) 5.28, 95% CI 1.75 to 15.93), arterial carbon dioxide tension (HR 1.07, 95% CI 1.02 to 1.12), and acute exacerbations of COPD were found to be independent indicators of a poor prognosis. The patients with the greatest mortality risk were those with three or more acute COPD exacerbations (HR 4.13, 95% CI 1.80 to 9.41).

CONCLUSIONS

This study shows for the first time that severe acute exacerbations of COPD have an independent negative impact on patient prognosis. Mortality increases with the frequency of severe exacerbations, particularly if these require admission to hospital.

Analysis of the stability of stored adenosine 5'-monophosphate used for bronchoprovocation

Adenosine 5'-monophosphate (AMP) bronchial challenge has been shown to be very useful tool in the diagnosis of asthma. Freshly test solutions are prepared just prior to each test in most of the studies. The objective of this study was to assess the stability of AMP solutions at different temperatures using a reversed-phase high-performance liquid chromatography assay. Sodium salt AMP solutions in concentrations of 0.03 mg/ml and 400 mg/ml were analyzed. One aliquot was kept at room temperature (20-25 degrees C) and the others were refrigerated at 4 degrees C. Room temperature stored samples were analyzed daily. Refrigerated stored samples were analyzed daily for first 15 days and then weekly. The duration of the study was 25 weeks. Samples were injected into the chromatograph column in quadruplicate and quantification was based on the arithmetic mean and standard deviation (+/-SD) of four measurements. Room temperature stored samples at concentrations of 0.03 mg/ml showed a mean percent variation greater than 10% at day 9 and greater than 75% at day 14. Samples at concentrations of 400 mg/ml maintained almost the initial concentration during the first 10 days, but decomposition occurred thereafter. In contrast, there was no significant degradation of refrigerated stored samples throughout the study period. We conclude the exposure to room temperature of AMP solutions results in a substantial loss of the initial concentration, but the shelf life of adequately prepared stock AMP solutions stored at 4 degrees C is at least 25 weeks.

Diagnostic utility of eosinophils in the pleural fluid

This study was conducted to assess the prevalence of eosinophilia in 358 consecutive samples of pleural fluid (all cases corresponded to first thoracentesis), to review the cause of eosinophilic pleural effusions, and to determine whether the presence of eosinophils increases the likelihood of nonmalignant underlying disorders. Eosinophilic pleural effusions were identified in 45 patients (12.6%): malignant underlying conditions were diagnosed in 11 patients (24.4% with eosinophilic effusions) and benign aetiologies were found in 27 patients. Benign aetiologies included uncomplicated paraneumonic effusion in 10 patients, tuberculosis in seven, complicated paraneumonic in five, liver cirrhosis in three, hydronephrosis in one and pulmonary thromboembolism in one. Seven pleural effusions were idiopathic. There was no difference in the prevalence between eosinophilic and noneosinophilic effusions according to the different diagnoses. With parameters of sensitivity, specificity, pretest and post-test probability and positive and negative predictive values for any prevalence figure using the Bayes' theorem and for any value of eosinophils (both in percentage or absolute numbers) in the pleural fluid (receiver operating characteristic curve) an adequate predictor of benign disease was not found. It is concluded that pleural eosinophilia at the initial thoracentesis cannot be considered as a predictor of an underlying benign disorder.