Send to

Choose Destination
Multidiscip Respir Med. 2019 Feb 5;14:7. doi: 10.1186/s40248-019-0168-5. eCollection 2019.

Predictive factors for exacerbation and re-exacerbation in chronic obstructive pulmonary disease: an extension of the Cox model to analyze data from the Swiss COPD cohort.

Author information

1University Clinic of Medicine, Cantonal Hospital Baselland, University of Basel, Rheinstrasse 26, 4410 Liestal, Switzerland.
2University Hospital Basel, University of Basel, Spitalstrasse 21, 4031 Basel, Switzerland.
3Hospital of Valais, University of Geneva, Avenue du Grand-Champsec 80, 1950 Sion, Switzerland.
4University Hospital Bern (Inselspital), University of Bern, Freiburgstrasse 18, 3010 Bern, Switzerland.
5St. Clara Hospital, University of Basel, Kleinriehenstrasse 30, 4002 Basel, Switzerland.
6University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091 Zürich, Switzerland.
Cantonal Hospital of Muensterlingen, Spitalcampus 1, 8596 Münsterlingen, Switzerland.



The Swiss COPD cohort was established in 2006 to collect data in a primary care setting. The objective of this study was to evaluate possible predictive factors for exacerbation and re-exacerbation.


In order to predict exacerbation until the next visit based on the knowledge of exacerbation since the last visit, a multistate model described by Therneau and Grambsch was performed.


Data of 1,247 patients (60.4% males, 46.6% current smokers) were analyzed, 268 (21.5%) did not fulfill spirometric diagnostic criteria for COPD. Data of 748 patients (63% males, 44.1% current smokers) were available for model analysis. In order to predict exacerbation an extended Cox Model was performed. Mean FEV1/FVC-ratio was 53.1% (±11.5), with a majority of patients in COPD GOLD classes 2 or 3. Hospitalization for any reason (HR1.7; P = 0.04) and pronounced dyspnea (HR for mMRC grade four 3.0; P < 0.001) at most recent visit as well as prescription of short-acting bronchodilators (HR1.7; P < 0.001), inhaled (HR1.2; P = 0.005) or systemic corticosteroids (HR1.8; P = 0.015) were significantly associated with exacerbation when having had no exacerbation at most recent visit. Higher FEV1/FVC (HR0.9; P = 0.008) and higher FEV1 values (HR0.9; P = 0.001) were protective. When already having had an exacerbation at the most recent visit, pronounced dyspnea (HR for mMRC grade 4 1.9; P = 0.026) and cerebrovascular insult (HR2.1; P = 0.003) were significantly associated with re-exacerbation. Physical activity (HR0.6; P = 0.031) and treatment with long-acting anticholinergics (HR0.7; P = 0.044) seemed to play a significant protective role. In a best subset model for exacerbation, higher FEV1 significantly reduced and occurrence of sputum increased the probability of exacerbation. In the same model for re-exacerbation, coronary heart disease increased and hospitalization at most recent visit seemed to reduce the risk for re-exacerbation.


Our data confirmed well-established risk factors for exacerbations whilst analyzing their predictive association with exacerbation and re-exacerbation. This study confirmed the importance of spirometry in primary care, not only for diagnosis but also as a risk evaluation for possible future exacerbations.

Trial registration:

Our study got approval by local ethical committee in 2006 (EK Nr. 170/06) and was registered retrospectively on (NCT02065921, 19th of February 2014).


COPD; Exacerbation; Primary health care; Re-exacerbation; Risk factors

Conflict of interest statement

We received ethical approval for this study by the local ethical committee (Ethikkommission Nordwest- und Zentralschweiz (EKNZ), formerly Ethikkommission beider Basel (EKBB)) in 2006 (EK Nr. 170/06) and subsequently by ethical committees of all other participating Swiss cantons. The study was also registered on (NCT02065921).Not applicable.The authors declare that they have no competing interests in relation to the work described.Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplemental Content

Full text links

Icon for BioMed Central Icon for PubMed Central
Loading ...
Support Center