Table 1.
Comparisons of COPD patient cohorts identified from claim data using different criteria of ICD9-CM codes
| ICD9-CM COPD codes
|
P-value | |||||
|---|---|---|---|---|---|---|
| ≥2 outpatients or ≥1 inpatients | ≥2 outpatients or ≥2 inpatients | ≥3 outpatients or ≥1 inpatients | ≥4 outpatients or ≥1 inpatients | ≥3 outpatients or ≥2 inpatients | ||
|
|
|
|
|
|
|
|
| n=12,127 | n=10,699 | n=10,053 | n=8,837 | n=8,485 | ||
| Age, years | 70.0±12.2 | 69.4±12.1 | 70.9±11.9 | 71.5±11.7 | 70.2±11.9 | <0.001 |
| ≥65 | 7,996 (65.9) | 6,857 (64.1) | 6,959 (69.2) | 6,310 (71.4) | 5,708 (67.3) | <0.001 |
| Male sex | 8,971 (74.0) | 7,855 (73.4) | 7,574 (75.3) | 6,753 (76.4) | 6,343 (74.8) | <0.001 |
| Smoking status | ||||||
| Smoker/ex-smoker | 8,604 (70.9) | 7,295 (68.2) | 7,556 (75.2) | 6,888 (77.9) | 6,114 (72.1) | <0.001 |
| Never smoker | 1,762 (14.5) | 1,747 (16.3) | 1,292 (12.9) | 1,032 (11.7) | 1,276 (15.0) | |
| Unknown | 1,761 (14.5) | 1,657 (15.5) | 1,205 (12.0) | 917 (10.4) | 1,095 (12.9) | |
| CCI score, excluding COPD | 0.91±1.52 | 0.86±1.47 | 0.97±1.56 | 1.01±1.58 | 0.92±1.50 | <0.001 |
| 0 | 7,051 (58.1) | 6,346 (59.3) | 5,599 (55.7) | 4,776 (54.0) | 4,828 (56.9) | <0.001 |
| ≥1 | 5,076 (41.9) | 4,353 (40.7) | 4,454 (44.3) | 4,061 (46.0) | 3,657 (43.1) | |
| Comorbidities | ||||||
| Hypertension | 4,053 (33.4) | 3,691 (34.5) | 3,493 (34.7) | 3,119 (35.3) | 3,078 (36.3) | 0.001 |
| Coronary artery disease | 2,145 (17.7) | 1,894 (17.7) | 1,850 (18.4) | 1,666 (18.9) | 1,567 (18.5) | 0.130 |
| Diabetes mellitus | 1,736 (14.3) | 1,524 (14.2) | 1,509 (15.0) | 1,367 (15.5) | 1,271 (15.0) | 0.074 |
| Heart failure | 1,238 (10.2) | 1,018 (9.5) | 1,094 (10.9) | 1,000 (11.3) | 845 (10.0) | <0.001 |
| Cerebrovascular disease | 1,120 (9.2) | 943 (8.8) | 994 (9.9) | 912 (10.3) | 794 (9.4) | 0.003 |
| Physician verification | ||||||
| COPD | 7,701 (63.5) | 7,006 (65.5) | 6,923 (68.9) | 6,330 (71.6) | 6,125 (72.2) | <0.001 |
| Indeterminate | 1,502 (12.4) | 987 (9.2) | 1,261 (12.5) | 1,136 (12.9) | 729 (8.6) | |
| Not COPD | 2,924 (24.1) | 2,706 (25.3) | 1,869 (18.6) | 1,371 (15.5) | 1,631 (19.2) | |
| Spirometry-confirmed COPD | 5,963 (49.2) | 5,531 (51.7) | 5,340 (53.1) | 4,874 (55.2) | 4,838 (57.0) | <0.001 |
| Spirometry done | n=7,914 | n=7,341 | n=6,593 | n=5,781 | n=5,933 | |
| GOLD stage | ||||||
| I | 2,682 (45.0) | 2,532 (45.8) | 2,309 (43.2) | 2,049 (42.0) | 2,130 (44.0) | 0.062 |
| II | 2,279 (38.2) | 2,084 (37.7) | 2,084 (39.0) | 1,930 (39.6) | 1,864 (38.5) | |
| III | 844 (14.2) | 775 (14.0) | 793 (14.9) | 746 (15.3) | 710 (14.7) | |
| IV | 158 (2.6) | 140 (2.5) | 154 (2.9) | 149 (3.1) | 134 (2.8) | |
Abbreviation: CCI, Charlson Comorbidity Index.