The St. George's Respiratory Questionnaire Definition of Chronic Bronchitis May Be a Better Predictor of COPD Exacerbations Compared With the Classic Definition

Victor Kim, Huaqing Zhao, Elizabeth Regan, MeiLan K Han, Barry J Make, James D Crapo, Paul W Jones, Jeffrey L Curtis, Edwin K Silverman, Gerard J Criner, COPDGene Investigators, James D Crapo, Edwin K Silverman, Barry J Make, Elizabeth A Regan, Terri Beaty, Ferdouse Begum, Robert Busch, Peter J Castaldi, Michael Cho, Dawn L DeMeo, Adel R Boueiz, Marilyn G Foreman, Eitan Halper-Stromberg, Nadia N Hansel, Megan E Hardin, Lystra P Hayden, Craig P Hersh, Jacqueline Hetmanski, Brian D Hobbs, John E Hokanson, Nan Laird, Christoph Lange, Sharon M Lutz, Merry-Lynn McDonald, Margaret M Parker, Dandi Qiao, Elizabeth A Regan, Stephanie Santorico, Edwin K Silverman, Emily S Wan, Sungho Won, Jean-Paul Charbonnier, Harvey O Coxson, MeiLan K Han, Eric A Hoffman, Stephen Humphries, Francine L Jacobson, Philip F Judy, Ella A Kazerooni, Alex Kluiber, David A Lynch, John D Newell Jr, Elizabeth A Regan, James C Ross, Raul San Jose Estepar, Jered Sieren, Berend C Stoel, Juerg Tschirren, Edwin Van Beek, Bram van Ginneken, Eva van Rikxoort, George Washko, Carla G Wilson, Robert Jensen, Douglas Everett, Jim Crooks, Camille Moore, Matt Strand, Carla G Wilson, John E Hokanson, John Hughes, Gregory Kinney, Sharon M Lutz, Katherine Pratte, Kendra A Young, Jeffrey L Curtis, Carlos H Martinez, Perry G Pernicano, Nicola Hanania, Philip Alapat, Mustafa Atik, Venkata Bandi, Aladin Boriek, Kalpatha Guntupalli, Elizabeth Guy, Arun Nachiappan, Amit Parulekar, Dawn L DeMeo, Craig Hersh, Francine L Jacobson, George Washko, R Graham Barr, John Austin, Belinda D'Souza, Gregory D N Pearson, Anna Rozenshtein, Byron Thomashow, Neil MacIntyre Jr, H Page McAdams, Lacey Washington, Charlene McEvoy, Joseph Tashjian, Robert Wise, Robert Brown, Nadia N Hansel, Karen Horton, Allison Lambert, Nirupama Putcha, Richard Casaburi, Alessandra Adami, Matthew Budoff, Hans Fischer, Janos Porszasz, Harry Rossiter, William Stringer, Amir Sharafkhaneh, Charlie Lan, Christine Wendt, Brian Bell, Marilyn G Foreman, Eugene Berkowitz, Eric L Flenaugh, Gloria Westney, Russell Bowler, David A Lynch, Richard Rosiello, David Pace, Gerard Criner, David Ciccolella, Francis Cordova, Chandra Dass, Gilbert D'Alonzo, Parag Desai, Michael Jacobs, Steven Kelsen, Victor Kim, A James Mamary, Nathaniel Marchetti, Aditi Satti, Kartik Shenoy, Robert M Steiner, Maria Elena Vega-Sanchez, Mark Dransfield, William Bailey, Surya Bhatt, Anand Iyer, Hrudaya Nath, Gabriela Oates, Sushil Sonavane, J Michael Wells, Joe Ramsdell, Paul Friedman, Xavier Soler, Andrew Yen, Alejandro P Comellas, John Newell Jr, Brad Thompson, MeiLan K Han, Ella Kazerooni, Carlos H Martinez, Joanne Billings, Abbie Begnaud, Tadashi Allen, Frank Sciurba, Jessica Bon, Divay Chandra, Carl Fuhrman, Joel Weissfeld, Antonio Anzueto, Sandra Adams, Diego Maselli-Caceres, Mario E Ruiz, Victor Kim, Huaqing Zhao, Elizabeth Regan, MeiLan K Han, Barry J Make, James D Crapo, Paul W Jones, Jeffrey L Curtis, Edwin K Silverman, Gerard J Criner, COPDGene Investigators, James D Crapo, Edwin K Silverman, Barry J Make, Elizabeth A Regan, Terri Beaty, Ferdouse Begum, Robert Busch, Peter J Castaldi, Michael Cho, Dawn L DeMeo, Adel R Boueiz, Marilyn G Foreman, Eitan Halper-Stromberg, Nadia N Hansel, Megan E Hardin, Lystra P Hayden, Craig P Hersh, Jacqueline Hetmanski, Brian D Hobbs, John E Hokanson, Nan Laird, Christoph Lange, Sharon M Lutz, Merry-Lynn McDonald, Margaret M Parker, Dandi Qiao, Elizabeth A Regan, Stephanie Santorico, Edwin K Silverman, Emily S Wan, Sungho Won, Jean-Paul Charbonnier, Harvey O Coxson, MeiLan K Han, Eric A Hoffman, Stephen Humphries, Francine L Jacobson, Philip F Judy, Ella A Kazerooni, Alex Kluiber, David A Lynch, John D Newell Jr, Elizabeth A Regan, James C Ross, Raul San Jose Estepar, Jered Sieren, Berend C Stoel, Juerg Tschirren, Edwin Van Beek, Bram van Ginneken, Eva van Rikxoort, George Washko, Carla G Wilson, Robert Jensen, Douglas Everett, Jim Crooks, Camille Moore, Matt Strand, Carla G Wilson, John E Hokanson, John Hughes, Gregory Kinney, Sharon M Lutz, Katherine Pratte, Kendra A Young, Jeffrey L Curtis, Carlos H Martinez, Perry G Pernicano, Nicola Hanania, Philip Alapat, Mustafa Atik, Venkata Bandi, Aladin Boriek, Kalpatha Guntupalli, Elizabeth Guy, Arun Nachiappan, Amit Parulekar, Dawn L DeMeo, Craig Hersh, Francine L Jacobson, George Washko, R Graham Barr, John Austin, Belinda D'Souza, Gregory D N Pearson, Anna Rozenshtein, Byron Thomashow, Neil MacIntyre Jr, H Page McAdams, Lacey Washington, Charlene McEvoy, Joseph Tashjian, Robert Wise, Robert Brown, Nadia N Hansel, Karen Horton, Allison Lambert, Nirupama Putcha, Richard Casaburi, Alessandra Adami, Matthew Budoff, Hans Fischer, Janos Porszasz, Harry Rossiter, William Stringer, Amir Sharafkhaneh, Charlie Lan, Christine Wendt, Brian Bell, Marilyn G Foreman, Eugene Berkowitz, Eric L Flenaugh, Gloria Westney, Russell Bowler, David A Lynch, Richard Rosiello, David Pace, Gerard Criner, David Ciccolella, Francis Cordova, Chandra Dass, Gilbert D'Alonzo, Parag Desai, Michael Jacobs, Steven Kelsen, Victor Kim, A James Mamary, Nathaniel Marchetti, Aditi Satti, Kartik Shenoy, Robert M Steiner, Maria Elena Vega-Sanchez, Mark Dransfield, William Bailey, Surya Bhatt, Anand Iyer, Hrudaya Nath, Gabriela Oates, Sushil Sonavane, J Michael Wells, Joe Ramsdell, Paul Friedman, Xavier Soler, Andrew Yen, Alejandro P Comellas, John Newell Jr, Brad Thompson, MeiLan K Han, Ella Kazerooni, Carlos H Martinez, Joanne Billings, Abbie Begnaud, Tadashi Allen, Frank Sciurba, Jessica Bon, Divay Chandra, Carl Fuhrman, Joel Weissfeld, Antonio Anzueto, Sandra Adams, Diego Maselli-Caceres, Mario E Ruiz

Abstract

Background: Chronic bronchitis (CB) increases risk of COPD exacerbations. We have shown that the St. George's Respiratory Questionnaire (SGRQ) CB definition identifies patients with a similar clinical phenotype as classically defined CB. Whether the SGRQ CB definition is a predictor of future COPD exacerbations is unknown.

Methods: We analyzed 7,557 smokers with normal spirometry and Global Initiative for Chronic Obstructive Lung Disease stage 1-4 COPD in the Genetic Epidemiology of COPD study with longitudinal follow-up data on exacerbations. Subjects were divided into classic CB+ or classic CB-, using the classic definition. In addition, subjects were divided into SGRQ CB+ or SGRQ CB-. Exacerbation frequency and severe exacerbation frequency were determined in each group. Multivariable linear regressions were performed for exacerbation frequency with either classic CB or SGRQ CB and relevant covariates.

Results: There were 1,434 classic CB+ subjects and 2,290 SGRQ CB+ subjects. The classic CB+ group had a greater exacerbation frequency compared with the classic CB- group (0.69 ± 1.26 vs 0.36 ± 0.90 exacerbations per patient per year; P < .0001) and a greater severe exacerbation frequency (0.26 ± 0.74 vs 0.13 ± 0.46 severe exacerbations per patient per year; P < .0001). There were similar differences between the SGRQ CB+ and SGRQ CB- groups. In multivariable analysis, both SGRQ CB and classic CB were independent predictors of exacerbation frequency, but SGRQ CB had a higher regression coefficient. In addition, SGRQ CB was an independent predictor of severe exacerbation frequency whereas classic CB was not.

Conclusions: The SGRQ CB definition identified more subjects at risk for future exacerbations than the classic CB definition. SGRQ CB was at least a similar if not better predictor of future exacerbations than classic CB.

Trial registration: ClinicalTrials.gov NCT00608764.

Keywords: COPD; chronic bronchitis; cough; exacerbations.