Relative impact of COPD and comorbidities on generic health-related quality of life: a pooled analysis of the COSYCONET patient cohort and control subjects from the KORA and SHIP studies.

Margarethe E Wacker,Joachim Heinrich,Sebastian E Baumeister,Ralf Ewert,Sven Gläser,Rolf Holle,Armin Koch,Holger Schulz,Reiner Leidl,Stefan Karrasch,Rudolf A Jörres,Annika Karch,Annette Peters,Claus Vogelmeier

doi:10.1186/s12931-016-0401-0

Abstract

BackgroundHealth-related quality of life (HRQL) is an important patient-reported outcome measure used to describe the burden of chronic obstructive pulmonary disease (COPD) which is often accompanied by comorbid conditions.MethodsData from 2275 participants in the COPD cohort COSYCONET and from 4505 lung-healthy control subjects from the population-based KORA and SHIP studies were pooled. Main outcomes were the five dimensions of the generic EQ-5D-3 L questionnaire and two EQ-5D index scores using a tariff based on valuations from the general population and an experience-based tariff.The association of COPD in GOLD grades 1–4 and of several comorbid conditions with the EQ-5D index scores was quantified by multiple linear regression models while adjusting for age, sex, education, body mass index (BMI), and smoking status.ResultsFor all dimensions of the EQ-5D, the proportion of participants reporting problems was higher in the COPD group than in control subjects. COPD was associated with significant reductions in the EQ-5D index scores (-0.05 points for COPD grades 1/2, -0.09 for COPD grade 3, -0.18 for COPD grade 4 according to the preference-based utility tariff, all p < 0.0001). Adjusted mean index scores were 0.89 in control subjects and 0.85, 0.84, 0.81, and 0.72 in COPD grades 1-4 according to the preference-based utility tariff and 0.76, 0.71, 0.68, 0.64, and 0.58 for control subjects and COPD grades 1-4 for the experience-based tariff respectively. Comorbidities had additive negative effects on the index scores; the effect sizes for comorbidities were comparable to or smaller than the effects of COPD grade 3. No statistically significant interactions between COPD and comorbidities were observed. Score differences between COPD patients and control subjects were most pronounced in younger age groups.ConclusionsCompared with control subjects, the considerable reduction of HRQL in patients with COPD was mainly due to respiratory limitations, but observed comorbidities added linearly to this effect. Younger COPD patients showed a greater loss of HRQL and may therefore be in specific need of comprehensive disease management.Trial registrationNCT01245933

Highlights

Health-related quality of life (HRQL) is an important patient-reported outcome measure used to describe the burden of chronic obstructive pulmonary disease (COPD) which is often accompanied by comorbid conditions
Compared with control subjects, the considerable reduction of HRQL in patients with COPD was mainly due to respiratory limitations, but observed comorbidities added linearly to this effect
Younger COPD patients showed a greater loss of HRQL and may be in specific need of comprehensive disease management

Summary

Introduction

Health-related quality of life (HRQL) is an important patient-reported outcome measure used to describe the burden of chronic obstructive pulmonary disease (COPD) which is often accompanied by comorbid conditions. Patients with COPD are affected to a varying extent by symptoms such as chronic cough, phlegm, dyspnea, and by acute exacerbations or episodes of acute worsening of the respiratory symptoms. These characteristics of COPD are associated with limitations in health-related quality of life (HRQL) [3,4,5,6,7]. Several studies have demonstrated that comorbidities contribute to low HRQL in patients with COPD [9, 12,13,14], there is no evidence whether the effect of comorbid conditions on HRQL differs between patients with COPD and individuals without COPD

Objectives

Methods

Results

Discussion

Conclusion