Table 1.
Baseline Characteristics and Risk Factors
| Baseline Exacerbation Status | ||||
|---|---|---|---|---|
| Measurea | All (N = 92,496) | None (n = 72,856) | Any Moderate (n = 12,930) | Any Severe (n = 10,378) |
| Demographic | ||||
| Age, mean (± SD) | 69.00 (±9.2) | 68.98 (±9.3) | 68.53 (±8.6) | 69.74 (±8.8) |
| Female | 48,668 (52.6) | 38,403 (52.7) | 6,881 (53.2) | 5,300 (51.1) |
| U.S. region | ||||
| Northeast | 2,046 (2.2) | 1,586 (2.2) | 297 (2.3) | 266 (2.6) |
| Midwest | 21,577 (23.3) | 16,615 (22.8) | 3,210 (24.8) | 2,752 (26.5) |
| South | 60,057 (64.9) | 47,612 (65.4) | 8,270 (64.0) | 6,433 (62.0) |
| West | 8,816 (9.5) | 7,043 (9.7) | 1,153 (8.9) | 927 (8.9) |
| Medicare insurance | 88,956 (96.2) | 69,862 (95.9) | 12,531 (96.9) | 10,179 (98.1) |
| H1N1 flu season overlapped with at-risk period | 19,242 (20.8) | 14,972 (20.6) | 2,560 (19.8) | 2,565 (24.7) |
| Medical | ||||
| Baseline exacerbations | ||||
| 1 moderate | 8,475 (9.2) | 0 | 8,475 (65.5) | 1,889 (18.2) |
| ≥ 2 moderate | 4,455 (4.8) | 0 | 4,455 (34.5) | 1,779 (17.1) |
| 1 severe | 6,172 (6.7) | 0 | 1,953 (15.1) | 6,172 (59.5) |
| ≥ 2 two severe | 4,206 (4.5) | 0 | 1,715 (13.3) | 4,206 (40.5) |
| Type of COPD diagnosis | ||||
| Chronic bronchitis (491.xx) | 24,551 (26.5) | 16,840 (23.1) | 4,958 (38.3) | 4,753 (45.8) |
| Emphysema (492.xx) | 5,344 (5.8) | 4,277 (5.9) | 658 (5.1) | 586 (5.6) |
| Chronic airway obstruction (496.xx) | 62,601 (67.7) | 51,739 (71.0) | 7,314 (56.6) | 5,039 (48.6) |
| Comorbidities | ||||
| Respiratory infection | 47,220 (51.1) | 32,701 (44.9) | 8,923 (69.0) | 8,869 (85.5) |
| Congestive heart failure | 24,316 (26.3) | 16,642 (22.8) | 3,745 (29.0) | 5,753 (55.4) |
| Sleep apnea | 13,848 (15.0) | 10,101 (13.9) | 2,185 (16.9) | 2,378 (22.9) |
| Risk smoker | 38,675 (41.8) | 27,627 (37.9) | 7,195 (55.6) | 6,518 (62.8) |
| Procedures | ||||
| Flu vaccine | 41,469 (44.8) | 32,347 (44.4) | 6,247 (48.3) | 4,587 (44.2) |
| Chronic oxygen therapy | 23,868 (25.8) | 14,651 (20.1) | 5,788 (44.8) | 5,922 (57.1) |
| Nebulizer | 13,448 (14.5) | 8,376 (11.5) | 3,356 (26.0) | 2,992 (28.8) |
| Spirometry | 28,542 (30.9) | 20,517 (28.2) | 5,469 (42.3) | 4,274 (41.2) |
| Medications | ||||
| COPD medications | ||||
| CTR, mean (± SD)b | 0.42 (±0.4) | 0.41 (±0.4) | 0.43 (±0.3) | 0.42 (±0.4) |
| No controller medication | 37,097 (40.1) | 31,319 (43.0) | 3,447 (26.7) | 3,068 (29.6) |
| No controller medication and ≥ 4 canisters of rescue medication | 11,042 (11.9) | 8,879 (12.2) | 1,436 (11.1) | 1,102 (10.6) |
| ≥ 1 dispensing for oral corticosteroids | 39,680 (42.9) | 23,167 (31.8) | 12,917 (99.9) | 7,262 (70.0) |
| ≥ 4 dispensing for oral corticosteroids | 6,847 (7.4) | 2,364 (3.2) | 3,982 (30.8) | 2,184 (21.0) |
| ≥ 1 dispensing for theophylline | 3,013 (3.3) | 1,771 (2.4) | 905 (7.0) | 748 (7.2) |
| Concomitant medications | ||||
| Beta-blockers | 38,284 (41.4) | 29,729 (40.8) | 4,719 (36.5) | 5,450 (52.5) |
| Diuretics | 38,982 (42.1) | 29,246 (40.1) | 5,600 (43.3) | 6,179 (59.5) |
| Statins | 50,871 (55.0) | 40,377 (55.4) | 6,578 (50.9) | 5,835 (56.2) |
| Antidepressants | 33,665 (36.4) | 25,603 (35.1) | 5,111 (39.5) | 4,633 (44.6) |
| Rx-risk score, mean (± SD) | 7.25 (±3.1) | 7.01 (±3.0) | 7.79 (±3.0) | 8.79 (±3.1) |
aAll values given as n (%), unless otherwise stated.
bUnits of controller medication/(units of controller medication + units of rescue medication). One unit is equivalent to 1 canister. For medications not dispensed in canisters,
1 unit is equivalent to a 30-day supply.
COPD = chronic obstructive pulmonary disorder; CTR = COPD treatment ratio; SD = standard deviation.