Table 1.
Demographic and clinical characteristics of study sample according to study-defined episodic pain categories.
| Characteristic | All patients | Study-defined episodic cancer pain categoriesa | |||||
|---|---|---|---|---|---|---|---|
| Breakthrough pain | Incident pain | ||||||
| Total n = 371 (%) | Absent n = 231 (%) | Present n = 140 (%) | p value | Absent n = 190 (%) | Present n = 181 (%) | p value | |
| Age, mean yrs ± SD | 62.1 ± 14.3 | 62.5 ± 13.6 | 61.5 ± 15.5 | 0.494 | 62.6 ± 14.6 | 61.7 ± 14.1 | 0.534 |
| Sex: Female | 199 (53.6) | 128 (55.4) | 71 (50.7) | 0.379 | 104 (54.7) | 95 (52.5) | 0.664 |
| Primary cancer | |||||||
| Head and neck | 92 (24.8) | 44 (19.1) | 48 (34.3) | 0.022 | 42 (22.1) | 50 (27.6) | 0.185 |
| Lung | 10 (2.7) | 5 (2.2) | 5 (3.6) | 4 (2.1) | 6 (3.3) | ||
| Gastrointestinal | 82 (22.1) | 52 (22.5) | 30 (21.4) | 44 (23.2) | 38 (21.0) | ||
| Breast | 43 (11.6) | 31 (13.4) | 12 (8.6) | 22 (11.6) | 21 (11.6) | ||
| Genitourinary | 79 (21.3) | 54 (23.4) | 25 (17.9) | 36 (19.0) | 43 (23.8) | ||
| Others | 65 (17.5) | 45 (19.5) | 20 (14.3) | 42 (22.1) | 23 (12.7) | ||
| Metastatic sites | |||||||
| Bone | 129 (34.8) | 88 (38.1) | 41 (29.3) | 0.084 | 63 (33.2) | 66 (36.5) | 0.504 |
| Lungs | 53 (14.3) | 35 (15.2) | 18 (12.9) | 0.540 | 20 (10.5) | 33 (18.2) | 0.034 |
| CNS | 21 (5.7) | 16 (6.9) | 5 (3.6) | 0.175 | 6 (3.2) | 15 (8.3) | 0.033 |
| Liver | 58 (15.6) | 45 (19.5) | 13 (9.3) | 0.009 | 30 (15.8) | 28 (15.5) | 0.932 |
| Nodal | 59 (15.9) | 34 (14.7) | 25 (17.9) | 0.423 | 32 (16.8) | 27 (14.9) | 0.612 |
| Soft tissue | 47 (12.7) | 25 (10.8) | 22 (15.7) | 0.170 | 21 (11.1) | 26 (14.4) | 0.338 |
| Other | 106 (32.7) | 64 (31.1) | 42 (35.6) | 0.403 | 55 (32.5) | 51 (32.9) | 0.945 |
| Palliative goal | 176 (47.4) | 97 (42) | 79 (56.4) | 0.007 | 83 (43.7) | 93 (51.4) | 0.138 |
| Cognitive deficit | 46 (12.4) | 28 (12.1) | 18 (12.9) | 0.835 | 25 (13.2) | 21 (11.6) | 0.649 |
| Functional status (ECOG) | |||||||
| 0 | 120 (32.4) | 73 (31.6) | 47 (33.6) | 0.576 | 61 (32.1) | 59 (32.6) | 0.738 |
| 1 | 128 (34.5) | 86 (37.2) | 42 (30.0) | 62 (32.6) | 66 (36.5) | ||
| 2 | 61 (16.4) | 38 (16.5) | 23 (16.4) | 36 (19.0) | 25 (13.8) | ||
| 3 | 35 (9.4) | 19 (8.2) | 16 (11.4) | 18 (9.5) | 17 (9.4) | ||
| 4 | 27 (7.3) | 15 (6.5) | 12 (8.6) | 13 (6.8) | 14 (7.7) | ||
| Surgeryb | 112 (30.2) | 71 (30.7) | 41 (29.3) | 0.768 | 53 (27.9) | 59 (32.6) | 0.324 |
| Chemotherapyb | 167 (45.0) | 109 (47.2) | 58 (41.4) | 0.280 | 76 (40.0) | 91 (50.3) | 0.047 |
| Radiotherapyb | 176 (47.4) | 110 (47.6) | 66 (47.1) | 0.929 | 70 (36.8) | 106 (58.6) | <0.001 |
ECOG = eastern cooperative oncology group; CNS = central nervous system. aBased on both history and Brief Pain Inventory scores; bExposure within the last 30 days.