Table 2.
Characteristics of frequent and infrequent exacerbators, separately by cases and controls
| Characteristic | Cases
|
Controlsa
|
P-valueb | ||||
|---|---|---|---|---|---|---|---|
| Number of subjects | Infrequent | Frequent | Number of subjects | Infrequent | Frequent | ||
|
|
|
||||||
| Number (%) | Number (%) | Number (%) | Number (%) | ||||
| Sex | 3,594 | 2,547 (70.9) | 1,047 (29.1) | 10,782 | 7,765 (72.0) | 3,017 (28.0) | |
| Men | 1,870 | 1,336 (71.4) | 534 (28.6) | 5,610 | 4,105 (73.2) | 1,505 (26.8) | |
| Women | 1,724 | 1,211 (70.2) | 513 (29.8) | 5,172 | 3,660 (70.8) | 1,512 (29.2) | 0.005 |
| Index age (years) | 3,594 | 2,547 (70.9) | 1,047 (29.1) | 10,782 | 7,765 (72.0) | 3,017 (28.0) | |
| <60 | 268 | 194 (72.4) | 74 (27.6) | 800 | 575 (71.9) | 225 (28.1) | |
| 60–69 | 876 | 608 (69.4) | 268 (30.6) | 2,643 | 1,895 (71.7) | 748 (28.3) | |
| 70–79 | 1,418 | 981 (69.2) | 437 (30.8) | 4,280 | 3,051 (71.3) | 1,229 (28.7) | |
| 80 and over | 1,032 | 764 (74.0) | 268 (26.0) | 3,059 | 2,244 (73.4) | 815 (26.6) | 0.259 |
| Smoking statusc | 3,593 | 2,546 (70.9) | 1,047 (29.1) | 10,773 | 7,758 (72.0) | 3,015 (28.0) | |
| Nonsmoker | 369 | 276 (74.8) | 93 (25.2) | 1,089 | 779 (71.5) | 310 (28.5) | |
| Ex-smoker | 1,634 | 1,150 (70.4) | 484 (29.6) | 4,829 | 3,403 (70.5) | 1,426 (29.5) | |
| Current smoker | 1,590 | 1,120 (70.4) | 470 (29.6) | 4,855 | 3,576 (73.7) | 1,279 (26.3) | 0.002 |
| BMIc | 3,496 | 2,478 (70.9) | 1,016 (29.1) | 10,526 | 7,563 (71.9) | 2,963 (28.2) | |
| Underweight | 193 | 143 (74.1) | 50 (25.9) | 826 | 603 (73.0) | 223 (27.0) | |
| Normal weight | 1,109 | 783 (70.6) | 326 (29.4) | 3,910 | 2,779 (71.1) | 1,131 (28.9) | |
| Overweight | 1,123 | 796 (70.9) | 327 (29.1) | 3,393 | 2,427 (71.5) | 966 (28.5) | 0.266 |
| Obese | 1,069 | 756 (70.7) | 313 (29.3) | 2,397 | 1,754 (73.2) | 643 (26.8) | |
| Family history | 3,594 | 2,547 (70.9) | 1,047 (29.1) | 10,782 | 7,765 (72.0) | 3,017 (28.0) | |
| No | 2,597 | 1,824 (70.2) | 773 (29.8) | 7,870 | 5,686 (72.3) | 2,184 (27.8) | |
| Yes | 997 | 723 (72.5) | 274 (27.5) | 2,912 | 2,079 (71.4) | 833 (28.6) | 0.385 |
| Hypertension | 3,594 | 2,547 (70.9) | 1,047 (29.1) | 10,782 | 7,765 (72.0) | 3,017 (28.0) | |
| No | 1,764 | 1,246 (70.6) | 518 (29.4) | 5,436 | 3,863 (71.1) | 1,573 (28.9) | |
| Yes | 1,830 | 1,301 (71.1) | 529 (28.9) | 5,346 | 3,902 (73.0) | 1,444 (27.0) | 0.026 |
| Dyslipidemia | 3,594 | 2,547 (70.9) | 1,047 (29.1) | 10,782 | 7,765 (72.0) | 3,017 (28.0) | |
| No | 2,873 | 2,043 (71.1) | 830 (28.9) | 8,541 | 6,177 (72.3) | 2,364 (27.7) | |
| Yes | 721 | 504 (69.9) | 217 (30.1) | 2,241 | 1,588 (70.9) | 653 (29.1) | 0.172 |
| Diabetes | 3,594 | 2,547 (70.9) | 1,047 (29.1) | 10,782 | 7,765 (72.0) | 3,017 (28.0) | |
| No | 2,998 | 2,125 (70.9) | 873 (29.1) | 8,997 | 6,528 (72.6) | 2,469 (27.4) | |
| Yes | 596 | 422 (70.8) | 174 (29.2) | 1,785 | 1,237 (69.3) | 548 (30.7) | 0.005 |
| Atrial fibrillationc | 3,594 | 2,547 (70.9) | 1,047 (29.1) | 10,781 | 7,764 (72.0) | 3,017 (28.0) | |
| No | 3,129 | 2,216 (70.8) | 913 (29.2) | 9,593 | 6,912 (72.1) | 2,681 (28.0) | |
| Yes | 465 | 331 (71.2) | 134 (28.8) | 1,188 | 852 (71.7) | 336 (28.3) | 0.808 |
| Heart failurec | 3,594 | 2,547 (70.9) | 1,047 (29.1) | 10,780 | 7,763 (72.0) | 3,017 (28.0) | |
| No | 3,059 | 2,178 (71.2) | 881 (28.8) | 9,650 | 6,992 (72.5) | 2,658 (27.5) | |
| Yes | 535 | 369 (69.0) | 166 (31.0) | 1,130 | 771 (68.2) | 359 (31.8) | 0.003 |
| CVDs | 3,594 | 2,547 (70.9) | 1,047 (29.1) | 10,782 | 7,765 (72.0) | 3,017 (28.0) | |
| No CVD | 2,558 | 1,817 (71.0) | 741 (29.0) | 7,931 | 5,770 (72.8) | 2,161 (27.3) | |
| 1 CVD | 719 | 507 (70.5) | 212 (29.5) | 2,041 | 1,450 (71.0) | 591 (29.0) | |
| 2 or more CVDs | 317 | 223 (70.4) | 94 (29.7) | 810 | 545 (67.3) | 265 (32.7) | 0.003 |
Notes:
a
Including duplicates.
b
The reported P-value is for the association between exacerbation frequency and the listed covariate in the control group. Values in bold indicate significantly increased odds in frequent exacerbators compared with infrequent exacerbators.
c
Some missing data.
Abbreviations: BMI, body mass index; CVD, cardiovascular disease.