Table 1 Patient characteristics
Unadjusted total cohort | Cohort after sIPTW | |||||
|---|---|---|---|---|---|---|
Characteristic | Palbociclib + letrozole (n = 772) | Letrozole (n = 658) | Standardized difference | Palbociclib + letrozole (n = 839) | Letrozole (n = 698) | Standardized difference |
Age, y | ||||||
Mean (SD) | 65.2 (10.4) | 69.2 (10.9) | − 0.3793 | 66.8 (11.2) | 67.1 (11.1) | − 0.0288 |
Median (IQR) | 66.0 (58.0–73.0) | 70.0 (61.0–79.0) | 67.0 (59.0–75.0) | 68.0 (60.0–76.0) | ||
Age group*, n (%), y | ||||||
18–49 | 52 (6.7) | 30 (4.6) | 0.0944 | 48 (5.8) | 38 (5.5) | 0.0114 |
50–64 | 304 (39.4) | 187 (28.4) | 0.2331 | 288 (34.3) | 244 (35.0) | − 0.0131 |
65–74 | 262 (33.9) | 193 (29.3) | 0.0992 | 265 (31.6) | 221 (31.7) | − 0.0025 |
≥ 75 | 154 (19.9) | 248 (37.7) | − 0.3995 | 237 (28.3) | 194 (27.8) | 0.0107 |
Race/ethnicity*, n (%) | ||||||
White | 525 (68.0) | 446 (67.8) | 0.0048 | 572 (68.1) | 470 (67.4) | 0.0163 |
Black | 54 (7.0) | 60 (9.1) | − 0.0781 | 62 (7.4) | 55 (7.9) | − 0.0187 |
Asian | 13 (1.7) | 10 (1.5) | 0.0131 | 15 (1.7) | 11 (1.5) | 0.0180 |
Hispanic or Latino | 22 (2.8) | 15 (2.3) | 0.0361 | 23 (2.7) | 16 (2.3) | 0.0264 |
Not documented† | 158 (20.5) | 127 (19.3) | 0.0292 | 167 (20.0) | 146 (20.9) | − 0.0225 |
Practice type*, n (%) | ||||||
Academic | 46 (6.0) | 31 (4.7) | 0.0555 | 44 (5.2) | 36 (5.2) | 0.0010 |
Community | 726 (94.0) | 627 (95.3) | 795 (94.8) | 661 (94.8) | ||
Disease stage at initial diagnosis*, n (%) | ||||||
I | 82 (10.6) | 79 (12.0) | − 0.0437 | 90 (10.8) | 78 (11.2) | − 0.0127 |
II | 187 (24.2) | 149 (22.6) | 0.0373 | 198 (23.6) | 161 (23.1) | 0.0129 |
III | 109 (14.1) | 97 (14.7) | − 0.0177 | 121 (14.4) | 101 (14.4) | − 0.0017 |
IV | 321 (41.6) | 254 (38.6) | 0.0608 | 338 (40.3) | 283 (40.6) | − 0.0062 |
Not documented | 73 (9.5) | 79 (12.0) | − 0.0825 | 91 (10.9) | 74 (10.7) | 0.0069 |
ECOG PS*, n (%) | ||||||
0 | 293 (38.0) | 167 (25.4) | 0.2728 | 271 (32.3) | 227 (32.5) | − 0.0059 |
1 | 159 (20.6) | 134 (20.4) | 0.0057 | 175 (20.9) | 144 (20.7) | 0.0055 |
2, 3, or 4 | 49 (6.3) | 84 (12.8) | − 0.2196 | 82 (9.7) | 66 (9.5) | 0.0095 |
Not documented | 271 (35.1) | 273 (41.5) | − 0.1316 | 311 (37.1) | 260 (37.3) | − 0.0047 |
Visceral disease*,‡, n (%) | ||||||
No | 442 (57.3) | 437 (66.4) | 518 (61.8) | 429 (61.5) | ||
Yes | 330 (42.7) | 221 (33.6) | 0.1894 | 320 (38.2) | 269 (38.5) | − 0.0060 |
Bone-only disease*,§, n (%) | ||||||
No | 501 (64.9) | 398 (60.5) | 530 (63.1) | 440 (63.1) | ||
Yes | 271 (35.1) | 260 (39.5) | − 0.0913 | 309 (36.9) | 258 (36.9) | − 0.0011 |
Brain metastases, n (%) | ||||||
No | 753 (97.5) | 628 (95.4) | 820 (97.7) | 656 (94.0) | ||
Yes | 19 (2.5) | 30 (4.6) | − 0.1142 | 19 (2.3) | 42 (6.0) | − 0.1901 |
Time from initial Dx to metastatic Dx*, n (%), y | ||||||
De novo | 321 (41.6) | 254 (38.6) | 0.0608 | 338 (40.3) | 283 (40.6) | − 0.0062 |
≤ 1 | 19 (2.5) | 23 (3.5) | − 0.0609 | 25 (2.9) | 21 (3.1) | − 0.0070 |
> 1–5 | 123 (15.9) | 111 (16.9) | − 0.0253 | 133 (15.9) | 111 (16.0) | − 0.0016 |
> 5 | 308 (39.9) | 269 (40.9) | − 0.0201 | 342 (40.7) | 281 (40.3) | 0.0097 |
Not documented | 1 (0.1) | 1 (0.2) | − 0.0060 | 1 (0.1) | 1 (0.1) | 0.0010 |
Number of metastatic sites*,ǁ, n (%) | ||||||
1 | 372 (48.2) | 365 (55.5) | − 0.1462 | 423 (50.4) | 355 (50.9) | − 0.0104 |
2 | 220 (28.5) | 147 (22.3) | 0.1418 | 217 (25.9) | 183 (26.2) | − 0.0070 |
3 | 110 (14.2) | 64 (9.7) | 0.1396 | 101 (12.0) | 86 (12.4) | − 0.0104 |
4 | 40 (5.2) | 18 (2.7) | 0.1257 | 35 (4.2) | 27 (3.8) | 0.0184 |
≥ 5 | 20 (2.6) | 10 (1.5) | 0.0755 | 18 (2.2) | 15 (2.2) | 0.0002 |
Not documented | 10 (1.3) | 54 (8.2) | −0.3293 | 44 (5.3) | 31 (4.5) | 0.0371 |