Table 2.

Preoperative phenotypic differences between patients reporting persistent opioid use (6-months postoperatively) and those that did not

	Opioid use at 6 months
Day of surgery characteristics	No (N = 386)	Yes (N = 70)	p value
Age	63.48 (10.42)	62.57 (11.27)	0.509
Male	48.70%	37.10%	0.074
Caucasian	95.90%	94.20%	0.531
Knee surgery	40.50%	51.30%	0.087
WOMAC Pain (range = 3–20)	10.27 (3.25)	12.17 (3.67)	< 0.001
WOMAC Functioning (range = 8–61)	35.24 (10.24)	39.9 (12.5)	0.002
WOMAC Stiffness (range = 0–8)	4.45 (1.76)	5.27 (1.76)	0.001
WOMAC Total (range = 16–89)	49.96 (13.97)	57.22 (16.93)	< 0.001
BPI Overall Pain Severity (range = 0–10)	4.32 (1.9)	5.43 (1.99)	< 0.001
HADS Depression (range = 0–17)	4.3 (3.08)	5.49 (3.91)	0.006
HADS Anxiety (range = 0–20)	5.14 (3.5)	6.03 (4.17)	0.064
CSQ Catastrophizing (range = 0–36)	4.01 (4.99)	6.81 (8.42)	0.001

Note. WOMAC = Western Ontario and McMaster Universities Osteoarthritis Index; BPI = Brief Pain Inventory; HADS = Hospital and Anxiety and Depression Scale; CSQ = Coping Strategies Questionnaire-Catastrophizing subscale. Chi-square tests were conducted for categorical variables and independent sample t-tests were conducted for continuous variables. Mean and standard deviation were reported for continuous variables.