Table 2.
Severity of COPDa
| Severityc (%) | |||||||
|---|---|---|---|---|---|---|---|
| Study population | Country (sample size) | Criteria | Ageb (yr) | Stage 1 | Stage 2 | Stage 3 | Stage 4 |
| General population | |||||||
| Buist et al., 2007 [8] | Austria (1,349) | GOLD 2006 | ≥40 | 59.4 | 35.2 | 5.4 | |
| Germany (713) | 55.3 | 38.6 | 6.1 | ||||
| Poland (603) | 50.7 | 40.7 | 8.6 | ||||
| Norway (707) | 55.8 | 37.8 | 6.4 | ||||
| Shahab et al., 2006 [29] | United Kingdom (8,215) | GOLD 2006 | 55.5 (13.5) | 41.6 | 43.9 | 14.5 | |
| Lindberg et al., 2006 [47] | Sweden (1,237) | GOLD 2006 | 46-77 | 57.0 | 37.0 | 5.0 | 1.0 |
| BTS 1997 | 65.0 | 27.0 | 8.0 | NA | |||
| De Marco et al., 2004 [48]d | Belgium (1,122) | GOLD 2003 | 20-44 | 58.6 | 41.4 | ND | |
| Denmark (394) | 56.4 | 43.6 | ND | ||||
| France (2,137) | 66.7 | 33.3 | ND | ||||
| Germany (1,983) | 64.8 | 35.2 | ND | ||||
| Italy (910) | 69.4 | 30.6 | ND | ||||
| Ireland (454) | 75.3 | 24.7 | ND | ||||
| Netherlands (1,362) | 74.3 | 25.7 | ND | ||||
| Norway (969) | 40.7 | 59.3 | ND | ||||
| Spain (1,942) | 59.2 | 40.8 | ND | ||||
| Sweden (1,859) | 79.3 | 20.7 | ND | ||||
| Switzerland (853) | 76.3 | 23.7 | ND | ||||
| United Kingdom (1,198) | 69.8 | 30.2 | ND | ||||
| Tzanakis et al., 2004 [33] | Greece (888) | ERS 1995 | ≥35 | 58.2 | 25.6 | 16.2 | NA |
| Jansson et al., 2002 [49] | Sweden (212) | BTSe | 28-29 | 75.0 | 25.0 | 0 | 0 |
| 43-44 | 46.6 | 46.6 | 6.8 | 0 | |||
| 49-50 | 16.0 | 64.0 | 12.0 | 8.0 | |||
| 58-59 | 15.4 | 57.7 | 15.4 | 11.5 | |||
| 64-65 | 6.9 | 29.3 | 41.4 | 22.4 | |||
| 73-74 | 14.3 | 21.4 | 47.6 | 16.7 | |||
| 79-80 | 9.8 | 34.2 | 48.8 | 7.3 | |||
| Viegi et al., 2000 [36] | Italy (1,727) | ERS 1995 | ≥25 | 81.0 | 14.0 | 5.0 | NA |
| ATS 1995 | 98.2 | 1.8 | 0 | NA | |||
| Clinicalf | 86.1 | 13.9 | |||||
| Von Hertzen et al., 2000 [50]g | Finland (7,217) | ≥30 | 59.8 | 34.1 | 6.1 | NA | |
| General practitioner and/or chest specialist | |||||||
| Izquierdo et al., 2009 [51] | Spain (3,619) | GOLD 2006 | 67.0 (10.8) | 20.1 | 54.0 | 22.1 | 3.8 |
| Bednarek et al., 2008 [27] | Poland (1,960) | GOLD 2006 | 56.7 (11.6) | 30.6 | 51.4 | 15.3 | 2.7 |
| Hoogendoorn et al., 2006 [52] | Sweden (481) | GOLD 2006 | 65.5 | 30.0 | 51.0 | 17.0 | 2.0 |
| Piperno et al., 2005 [14] | France (3,411) | SPLF 1996 | 58.4 (9.9) | 31.3 | 50.2 | 18.5 | NA |
| Detournay et al., 2004 [53] | France (255) | SPLF 1996 | 67.1 | 56.0 | 27.0 | 17.0 | NA |
| Soriano et al., 2000 [54] | United Kingdom (23,277) | Prescriptions | 66.7 (15.5) | 35.5 | 56.4 | 8.1 | NA |
| Hospital | |||||||
| Soler-Cataluña et al., 2005 [55] | Netherlands (304) | GOLD 2006 | 71 (9) | 6.6 | 35.8 | 33.6 | 24.0 |
| Tsoumakidou et al., 2004 [56] | Greece (67) | ERS 1995 | 69.0 | 0 | 4.5 | 95.5 | NA |
| BTS 1997 | 69.5 | 1.5 | 14.9 | 83.6 | NA | ||
| ATS 1995 | 67.6 | 4.5 | 28.3 | 67.2 | NA | ||
| GOLD 2001 | 69.5 | 0 | 58.2 | 41.8 | |||
| Kornmann et al., 2003 [57] | Germany (1,434) | GOLD 2001 | {55} | 7.9 | 73.0 | 19.1 | |
aCOPD severity data are reported for the general population, inpatients, general practitioner reports, general practitioner and chest specialist reports or are taken from medical databases. bAge was reported in various ways distinguished here as follows: "≥ x", minimum age; "x" or "x (y)", mean age or mean age (SD); "x-y", age range i.e. min-max; "{x}", median age. mean age (±SD); median age; age range, min-max. cERS 1995, ATS 1995, BTS 1995 and SPLF 1995 classifications define only three stages. dIn this study, based on the GOLD 2003 severity scale, the estimates for stage 0 defining patients at risk of COPD ranged from 51.7% in Switzerland to 89.8% in Spain. ePatients with both FEV1/FVC <70% and FEV1 ≥80% (considered as having COPD in the GOLD 2006 classification but not in the BTS 1995 classification) were also included in the study. fAirway obstruction of any degree was defined by FEV1/FVC ratio <70% and the severity of obstruction was graded according to the FEV1 value: mild (FEV1 ≥70% of predicted) and moderate to severe (FEV1 <70% of predicted). gAirway obstruction of any degree was defined by FEV1/FVC ratio <80% and the severity of obstruction was graded according to the FEV1/FVC value: 70-79%, minimal to mild; 50-69%, moderate; <50%, severe. Abbreviations used: COPD, chronic obstructive pulmonary disease; ERS 1995, European Respiratory Society 1995 classification; ATS 1995, American Thoracic Society 1995 classification; BTS 1995, British Thoracic Society 1995 classification; SPLF 1995, Société de Pneumonologie de Langue Française 1995 classification; GOLD 2001, GOLD 2003 and GOLD 2006, Global Obstructive Lung Disease 2001, 2003 and 2006 classifications; ND, not defined; NA, not applicable; FEV1, maximum expiratory volume in 1 second; FVC, forced vital capacity.