Episodic Cancer Pain: Patient Reporting, Prevalence, and Clinicodemographic Associations at Initial Cancer Pain Clinic Assessment

Table 2

Cancer pain characteristics of participants in relation to breakthrough pain status.

Characteristic	Breakthrough pain^a		All patients	value
	Absent n = 231 (%)	Present n = 140 (%)	Total n = 371 (%)
Pain mechanisms and topography
Neuropathic pain component (NPC)	54 (23.4)	66 (47.1)	120 (32.4)	<0.001
Nociceptive pain
Visceral	76 (32.9)	36 (25.7)	112 (30.2)	0.144
Bone	93 (40.3)	56 (40.0)	149 (40.2)	0.961
Soft tissue	108 (46.8)	110 (78.6)	218 (58.8)	<0.001
Study-defined incident pain present	123 (53.3)	58 (41.4)	181 (48.8)	0.027
Pain duration
≤1 month	36 (15.6)	29 (20.7)	65 (17.5)	0.208
>1 month	195 (84.4)	111 (79.3)	306 (82.5)
Principal pain location
Upper limb	23 (10.0)	16 (11.4)	39 (10.5)	<0.001
Lower limb	33 (14.3)	17 (12.1)	50 (13.5)
Head and neck	36 (15.6)	54 (38.6)	90 (24.3)
Thorax	19 (8.2)	9 (6.4)	28 (7.6)
Breast	4 (1.7)	1 (0.7)	4 (1.4)
Back	27 (11.7)	13 (9.3)	40 (10.8)
Abdomen	39 (16.9)	11 (7.9)	50 (13.5)
Pelvis and perineum	31 (13.4)	16 (11.4)	47 (12.7)
Multiple sites	19 (8.2)	3 (2.1)	22 (5.9)
Brief pain inventory (BPI)
Worst pain	6.7 ± 2.9	8.4 ± 1.6	7.4 ± 2.6	<0.0001
Least pain	2.6 ± 2.0	3.6 ± 1.5	3.0 ± 1.9	<0.0001
Average pain	4.5 ± 2.1	5.6 ± 1.4	4.9 ± 1.9	<0.0001
Pain now	4.9 ± 2.8	6.2 ± 1.9	5.4 ± 2.6	<0.0001
Pain relief	49.7 ± 29.9	36.4 ± 26.1	44.7 ± 29.2	<0.0001
BPI pain interference
General activity	5.5 ± 2.5	5.2 ± 2.7	5.4 ± 2.6	0.179
Mood	7.4 ± 2.3	7.6 ± 2.6	7.5 ± 2.4	0.345
Walking	5.3 ± 2.6	5.3 ± 2.6	5.3 ± 2.6	0.991
Work	4.4 ± 2.8	4.6 ± 3.1	4.5 ± 2.9	0.540
Relations with people	2.9 ± 1.9	3.2 ± 1.9	3.0 ± 1.9	0.075
Sleep	5.0 ± 1.8	4.7 ± 2.1	4.9 ± 1.9	0.097
Enjoyment of life	7.4 ± 2.4	7.4 ± 2.5	7.4 ± 2.4	0.982

^aStudy-defined, based on history and on BPI scores.