The Coexistence of Asthma and Chronic Obstructive Pulmonary Disease (COPD): Prevalence and Risk Factors in Young, Middle-aged and Elderly People from the General Population

Abstract

Background

The joint distribution of asthma and chronic obstructive pulmonary disease (COPD) has not been well described. This study aims at determining the prevalence of self-reported physician diagnoses of asthma, COPD and of the asthma-COPD overlap syndrome and to assess whether these conditions share a common set of risk factors.

Methods

A screening questionnaire on respiratory symptoms, diagnoses and risk factors was administered by mail or phone to random samples of the general Italian population aged 20–44 (n = 5163) 45–64 (n = 2167) and 65–84 (n = 1030) in the frame of the multicentre Gene Environment Interactions in Respiratory Diseases (GEIRD) study.

Results

A physician diagnosis of asthma or COPD (emphysema/chronic bronchitis/COPD) was reported by 13% and 21% of subjects aged <65 and 65–84 years respectively. Aging was associated with a marked decrease in the prevalence of diagnosed asthma (from 8.2% to 1.6%) and with a marked increase in the prevalence of diagnosed COPD (from 3.3% to 13.3%). The prevalence of the overlap of asthma and COPD was 1.6% (1.3%–2.0%), 2.1% (1.5%–2.8%) and 4.5% (3.2%–5.9%) in the 20–44, 45–64 and 65–84 age groups. Subjects with both asthma and COPD diagnoses were more likely to have respiratory symptoms, physical impairment, and to report hospital admissions compared to asthma or COPD alone (p<0.01). Age, sex, education and smoking showed different and sometimes opposite associations with the three conditions.

Conclusion

Asthma and COPD are common in the general population, and they coexist in a substantial proportion of subjects. The asthma-COPD overlap syndrome represents an important clinical phenotype that deserves more medical attention and further research.

Contributors

Antony Bayer: Role: Editor

Journal

Journal ID (nlm-ta): PLoS One

Journal ID (iso-abbrev): PLoS ONE

Journal ID (publisher-id): plos

Journal ID (pmc): plosone

Title: PLoS ONE

Publisher: Public Library of Science (San Francisco, USA )

ISSN (Electronic): 1932-6203

Publication date Collection: 2013

Publication date (Electronic): 10 May 2013

Volume: 8

Issue: 5

Affiliations

[1 ]Unit of Epidemiology and Medical Statistics, University of Verona, Verona, Italy

[2 ]Allergy Unit, Dept of Immuno-Allergic and Respiratory Diseases, Ospedali Riuniti di Ancona, Ancona, Italy

[3 ]Unit of Respiratory Medicine, ASL TO-2, Torino, Italy

[4 ]Unit of Respiratory Diseases, Dept of Internal Medicine, University of Perugia, Perugia, Italy

[5 ]Unit of Internal Medicine, University of Verona, Verona, Italy

[6 ]Medical Affairs Department, Chiesi Farmaceutici, Parma, Italy

[7 ]Epidemiology Unit, ASL SA-2, Salerno, Italy

[8 ]Institute for Respiratory Diseases, University of Sassari, Sassari, Italy

[9 ]Unit of Respiratory Diseases, IRCCS Policlinico San Matteo, University of Pavia, Pavia, Italy

Cardiff University, United Kingdom

Author notes

* E-mail: roberto.demarco@ 123456univr.it

Competing Interests: The authors confirm that Gabriele Nicolini is an employe of the “Chiesi Farmaceutici, Parma, Italy,” one of the commercial funders of this research. There are no patents, products in development or marketed products to declare. This does not alter the authors’ adherence to all the PLOS ONE policies on sharing data and materials.

Reviewed the manuscript, contributed to its scientific content and approved the final version of it: RdM GP AM SA LA MB LC MF GN MGP PP MEZ IC GV. Conceived and designed the experiments: RdM. Analyzed the data: GP. Wrote the paper: RdM GP AM.

Article

Publisher ID: PONE-D-13-03419

DOI: 10.1371/journal.pone.0062985

PMC ID: 3651288

PubMed ID: 23675448

License:

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Page count

Pages: 7

Funding

The GEIRD project was funded by: the Cariverona Foundation, the Italian Ministry of Health, Chiesi Farmaceutici, and the Italian Medicines Agency (AIFA). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Categories

Subject: Research Article

Subject: Biology

Subject: Population Biology

Subject: Epidemiology

Subject: Medicine

Subject: Anatomy and Physiology

Subject: Respiratory System

Subject: Clinical Research Design

Subject: Survey Research

Subject: Epidemiology

Subject: Lifecourse Epidemiology

Subject: Survey Methods

Subject: Public Health

Subject: Health Screening

Subject: Pulmonology

Subject: Asthma

Subject: Chronic Obstructive Pulmonary Diseases