CT-defined emphysema in COPD patients and risk for change in desaturation status in 6-min walk test.

Background: Emphysema and exercise induced desaturation (EID) are both related to poorer COPD prognosis. More knowledge of associations between emphysema and desaturation is needed for more efficient disease management.

Research Question: Is emphysema a risk factor for both new and repeated desaturation, and is emphysema of more or less importance than other known risk factors?

Methods: 283 COPD patients completed a 6-min walk test (6MWT) at baseline and one year later in the Bergen COPD cohort study 2006-2011.

Prevalence and prognostic ability of the GOLD 2017 classification compared to the GOLD 2011 classification in a Norwegian COPD cohort.

Rationale: The Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2017 is based on an ABCD assessment tool of symptoms and exacerbation history and grade 1-4 of airflow limitation severity, facilitating classification either into 4 groups (ABCD) or 16 groups (1A-4D). We aimed to compare the GOLD 2011, GOLD 2017 ABCD, and GOLD 2017 1A-4D classifications in terms of their distribution and prediction of mortality and hospitalizations.

Methods: In the GenKOLS study, 912 COPD patients with FEV1 less than 80% of the predicted answered questionnaires and performed lung function testing in 2003-2005.

Diffusion capacity and CT measures of emphysema and airway wall thickness - relation to arterial oxygen tension in COPD patients.

Background: Decreased diffusing capacity of the lung for carbon monoxide (DLCO) is associated with emphysema. DLCO is also related to decreased arterial oxygen tension (PaO2), but there are limited data on associations between PaO2 and computed tomography (CT) derived measures of emphysema and airway wall thickness.

Objective: To examine whether CT measures of emphysema and airway wall thickness are associated with level of arterial oxygen tension beyond that provided by measurements of diffusion capacity and spirometry.

Oxygen desaturation in 6-min walk test is a risk factor for adverse outcomes in COPD.

The 6-min walk test (6MWT) is an exercise test that measures functional status in chronic obstructive pulmonary disease (COPD) patients and provides information on oxygen desaturation. We investigated oxygen desaturation during 6MWT as a risk factor for important COPD outcomes: mortality, frequency of exacerbations, decline in lung function and decline in lean body mass.433 COPD patients were included in the Bergen COPD Cohort Study 2006-2009, and followed-up for 3 years.

Zopiclone effects on breathing at sleep in stable chronic obstructive pulmonary disease.

Purpose: More than half of patients with chronic obstructive pulmonary disease (COPD) experiences sleep-related problems and about one fourth uses hypnotics regularly. We explored what the effect zopiclone, a commonly used hypnotic, had on nocturnal gas exchange and the apnea/hypopnea frequency in stable COPD.

Methods: Randomized crossover study of 31 (ten males) inpatients at a pulmonary rehabilitation hospital, median age 64 years, of which 20 had a forced expiratory volume first second <50% of predicted.

Alcohol at bedtime induces minor changes in sleep stages and blood gases in stable chronic obstructive pulmonary disease.

Purpose/background: The purpose of this study is to explore the effect of a moderate dose of alcohol on sleep architecture and respiration in chronic obstructive pulmonary disease (COPD). Alcohol depresses both hypercapnic and hypoxic ventilatory drives in awake, normal individuals and reduces the amount of rapid eye movement (REM) sleep and oxygen saturation (SpO2) in sleeping COPD subjects.

Methods: Prospectively designed, open-label interventional study in a pulmonary rehabilitation hospital.

Sleep hypoventilation and daytime hypercapnia in stable chronic obstructive pulmonary disease.

Purpose: To explore the associations between sleep hypoventilation (SH) and daytime arterial pressures of carbon dioxide (PaCO2), sleep stages, and sleep apneas/hypopneas (AHI) in subjects with chronic obstructive pulmonary disease (COPD). SH has previously been found in COPD-subjects with chronic hypercapnic respiratory failure (CHRF) using supplementary oxygen (LTOT), and has been proposed as a possible predictor for CHRF.

Patients And Methods: A prospectively designed observational study in a pulmonary rehabilitation hospital of 100 (39 male) stable COPD inpatients with a mean forced expiratory volume in 1 second (FEV1) of 1.

Reference values for within-breath pulmonary impedance parameters in asymptomatic elderly.

Introduction: A new application for the forced oscillation technique (FOT) has been described by Dellaca et al. using sinusoidal pressure variations at 5 Hz to detect expiratory flow limitation by measuring the within-breath reactance [termed difference between inspiratory and expiratory X5 (DX5)]. Few studies have been performed on respiratory phase differences in the elderly.

Chronic obstructive pulmonary disease is associated with low levels of vitamin D.

Introduction: COPD patients may be at increased risk for vitamin D (25(OH)D) deficiency, but risk factors for deficiency among COPD patients have not been extensively reported.

Methods: Serum 25(OH)D levels were measured by liquid chromatography double mass spectrometry in subjects aged 40-76 years from Western Norway, including 433 COPD patients (GOLD stage II-IV) and 325 controls. Levels <20 ng/mL defined deficiency.

Explained variance for blood gases in a population with COPD.

Introduction: Variation of blood gas levels in chronic obstructive pulmonary disease (COPD) patients has not been extensively reported and there is limited knowledge about predictors of chronic respiratory failure in COPD patients.

Objectives: The aim of this study was to identify predictors of hypoxemia, hypercapnia and increased alveolar-arterial oxygen difference in COPD patients. We hypothesized that prediction of arterial blood gases will be improved in multivariate models including measurements of lung function, anthropometry and systemic inflammation.

A randomised trial of endobronchial ultrasound guided sampling in peripheral lung lesions.

Aim: The aim of the study was to evaluate endobronchial ultrasound (EBUS) for peripheral lung lesions and to find the most cost effective combination of sampling techniques.

Materials: 264 patients with lesions suspicious of malignancy were recruited in Bergen and Aalesund, Norway from 2005 to 2008.

Methods: The study was a prospective randomised cohort study.

Cost minimization analysis for combinations of sampling techniques in bronchoscopy of endobronchial lesions.

Background: The choice of sampling techniques in bronchoscopy with sampling from a visible lesion will depend on the expected diagnostic yields and the costs of the sampling techniques.

Aims: The aim of this study was to determine the most economical combination of sampling techniques when approaching endobronchial visible lesions.

Methods: A cost minimization analysis was performed.