GOLD stage-specific phenotyping of emphysema and airway disease using quantitative computed tomography

Background

In chronic obstructive pulmonary disease (COPD) abnormal lung function is related to emphysema and airway obstruction, but their relative contribution in each GOLD-stage is not fully understood. In this study, we used quantitative computed tomography (QCT) parameters for phenotyping of emphysema and airway abnormalities, and to investigate the relative contribution of QCT emphysema and airway parameters to airflow limitation specifically in each GOLD stage.

Methods

Non-contrast computed tomography (CT) of 492 patients with COPD former GOLD 0 COPD and COPD stages GOLD 1-4 were evaluated using fully automated software for quantitative CT. Total lung volume (TLV), emphysema index (EI), mean lung density (MLD), and airway wall thickness (WT), total diameter (TD), lumen area (LA), and wall percentage (WP) were calculated for the entire lung, as well as for all lung lobes separately. Results from the 3rd-8th airway generation were aggregated (WT3-8, TD3-8, LA3-8, WP3-8). All subjects underwent whole-body plethysmography (FEV1%pred, VC, RV, TLC).

Results

EI was higher with increasing GOLD stages with 1.0 ± 1.8% in GOLD 0, 4.5 ± 9.9% in GOLD 1, 19.4 ± 15.8% in GOLD 2, 32.7 ± 13.4% in GOLD 3 and 41.4 ± 10.0% in GOLD 4 subjects (p < 0.001). WP3-8 showed no essential differences between GOLD 0 and GOLD 1, tended to be higher in GOLD 2 with 52.4 ± 7.2%, and was lower in GOLD 4 with 50.6 ± 5.9% (p = 0.010 - p = 0.960). In the upper lobes WP3-8 showed no significant differences between the GOLD stages (p = 0.824), while in the lower lobes the lowest WP3-8 was found in GOLD 0/1 with 49.9 ± 6.5%, while higher values were detected in GOLD 2 with 51.9 ± 6.4% and in GOLD 3/4 with 51.0 ± 6.0% (p < 0.05). In a multilinear regression analysis, the dependent variable FEV1%pred can be predicted by a combination of both the independent variables EI (p < 0.001) and WP3-8 (p < 0.001).

Conclusion

QCT parameters showed a significant increase of emphysema from GOLD 0-4 COPD. Airway changes showed a different spatial pattern with higher values of relative wall thickness in the lower lobes until GOLD 2 and subsequent lower values in GOLD3/4, whereas there were no significant differences in the upper lobes. Both, EI and WP5-8 are independently correlated with lung function decline.

[Relationship of chronic obstructive pulmonary disease and nutritional status - clinical observations]

Introduction: The increased metabolism of nutrients and the low energy intake may lead to malnutrition among chronic obstructive pulmonary disease (COPD) patients. Aim: The goal of our study was to examine the nutritional status of our population aged over 40, and its relationship with the severity of the disease. Method: We conducted a retrospective study at the National Korányi Institute of Pulmonology in 2017. Pulmonary function and anthropometric data were obtained from the electronic health record system. Inclusion criteria were age over 40 and the diagnosis of COPD. Severity of disease was assessed by forced expiration volume and categorized according to GOLD stages. We used SPSS Statistics V22.0 for data analysis. Results: The mean age of participants was 66; 49.3% were men, 50.7% were women. Average BMI was 27.14 kg/m², with values comprising cachexia and severe obesity. According to the FEV₁%pred results of the 3236 patients, 30% fell in the GOLD I, 40% in the GOLD II, 23% in the GOLD III, and 7% in the GOLD IV categories. Pearson coefficient found positive correlation between FEV₁ and nutritional status (H = 0.2297, r = 0.1401), specifically between severity of cachexia and severity of disease. The analysis of variance showed significant correlation between severity of disease and nutritional status; patients with higher BMI had better pulmonary function. Conclusion: Malnutrition had an adverse effect on pulmonary functions and performance of respiratory muscles, whereas higher BMI had a positive effect on FEV₁. Our results suggest that BMI could be used as a lung function prognostic indicator for COPD patients. Orv Hetil. 2019; 160(23): 908-913.

The annual direct costs of stable COPD in Greece

Introduction

Chronic obstructive pulmonary disease (COPD) places a major burden on health care systems and has substantial economic effects; however, the cost of stable disease in Greece has never been thoroughly explored. The objective of the study was to estimate the annual COPD patient cost during the maintenance phase and explore the relationships between the cost and disease severity.

Methods

Data were collected from 245 COPD patients (male: 231, mean age: 69.5±8.8 years) who visited the outpatient unit of University Hospital of Larissa in 2014 and 2015. Patients were classified according to Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines, and the patients’ direct cost during the maintenance phase was calculated.

Results

Eleven percent of COPD patients were stage I, 48.2% were stage II, 29% were stage III, and 11.8% were stage IV. According to the GOLD groups, 23.3% of patients were grade A, 15.5% were grade B, 22.9% were grade C, and 38.4% were grade D. The mean annual direct cost for stable disease was estimated at €1,034.55 per patient, of which €222.94 corresponded to out-of-pocket payments. The annual cost ranged from €408.23 to €2,041.89 depending on GOLD stages (I–IV) and from €550.01 to €1,480.00 depending on GOLD groups (A–D). The key cost driver was pharmaceutical treatment, which reflected almost 71% of the total expenses for the management of stable disease. The mean annual per-patient cost was two to three times higher for those with advanced disease (stages III–IV) compared to those with stages I–II disease, and it doubled for “high-risk” patients (groups C–D) compared to “low-risk” patients (groups A–B).

Conclusion

The cost of COPD during the maintenance phase is remarkable, with the key cost driver found to be pharmaceutical treatment and social insurance funds the key payer for treating COPD patients in Greece. The cost of stable disease is proportional to the severity of COPD, and it is doubled in patients who belong to high-risk groups.