The Relationship between Higher Chronic Opioid Therapy Dose and Specific Personality Traits in Individuals with Chronic Pain

Table 2

Clinical health information and descriptive statistics for the total sample and three morphine equivalent groups.

Variable	Total	MEQ 0 mg	MEQ 1–89 mg	MEQ 90+ mg
	N = 215	N = 58	N = 86	N = 71
Time since injury (years)	14.1 ± 10.2	8.6 ± 81	14.0 ± 10.1	18.9 ± 9.8	<0.001^a,b,c
Length of clinic enrolment (years)	7.4 ± 7.7	3.1 ± 4.7	7.5 ± 7.9	11.3 ± 7.7	<0.001^a,b,c
Type of pain					0.398
Nociceptive	78 (36.3%)	22 (37.9%)	33 (38.4%)	23 (32.4%)
Neuropathic	28 (13.0%)	4 (6.9%)	15 (17.4%)	9 (12.7%)
Mixed	102 (47.4%)	30 (51.7%)	34 (39.5%)	38 (53.5%)
Unknown	7 (3.3%)	2 (3.4%)	4 (4.7%)	1 (1.4%)
Opioid agents used^∗
Hydromorphone/contin	32 (14.9%)	N/A	14 (16.3%)	18 (25.4%)	0.170
Oxycontin/Oxyneo	39 (18.1%)		8 (9.3%)	31 (43.7%)	<0.001
Tramadol/Tramacet	19 (8.8%)		18 (20.9%)	1 (1.4%)	<0.001
Percocet	68 (31.6%)		32 (37.2%)	36 (50.7%)	0.106
Morphine/contin	38 (17.7%)		15 (17.4%)	23 (32.4%)	0.039
Fentanyl	12 (5.6%)		2 (2.3%)	10 (14.1%)	0.007
Tylenol 3 or 4	15 (7.0%)		14 (16.3%)	1 (1.4%)	0.002
Methadone	2 (0.9%)		0 (0.0%)	2 (2.8%)	0.203
Butrans	1 (0.5%)		1 (1.2%)	0 (0.0%)	1.00
Use of nonopioid medications					0.862
Yes	64 (29.8)	19 (32.8%)	25 (29.1%)	20 (28.2%)
No	151 (70.2)	39 (67.2%)	61 (70.9%)	51 (71.8%)
Morphine equivalent dose					N/A
Mean ± standard deviation	85.0 ± 123.2 (0–745)	N/A	36.0 ± 24.2 (2–88)	212.4 ± 142.9 (90–745)
Median (interquartile range)	40.0 (0–114)		35.5 (14.6–60.0)	165.0 (114–255)
Cannabis prescribed					0.754
Yes	63 (29.3%)	17 (29.3%)	23 (26.7%)	23 (32.4%)
No	149 (69.3%)	41 (70.7)	61 (70.9%)	47 (66.2%)
Unknown	3 (1.4%)	0 (0.0%)	2 (2.3%)	1 (1.4%)

^aMEQ = 0 mg vs. MEQ 1–89 mg significantly different ( < .05); ^bMEQ = 0 mg vs. MEQ 90+ mg significantly different ( < .05); ^cMEQ = 1–89 mg vs. MEQ 90+ mg significantly different ( < .05); ^∗Sum >215 as some patients were taking >1 opioid; MEQ = morphine equivalent.