Table 3.

Predictors of persistent opioid users in the subgroup with preoperative opioid use (n=50,120)

	Multivariable Odds Ratio a	95% Confidence Interval
Demographics
Age 50–59	1.00	0.86–1.15
Age 60–69	0.94	0.81–1.08
Age ≥70	Reference	-
Female v. male	1.03	0.94–1.13
Surgery characteristics
Knee surgery v. hip	1.75	1.59–1.93*
Discharge to a rehabilitation facility	1.23	1.09–1.39*
No. of days for in-hospital stay	1.04	1.02–1.06*
Preoperative opioid use
No. of months with opioid use	1.48	1.45–1.50*
≥1 month with a mean OME dose>100mg/day	1.44	1.20–1.74*
No. of months with PDC >80%
0	Reference	-
1–3	2.54	2.26–2.85*
4–6	3.32	2.79–3.95*
7+	4.54	3.79–5.44*
Multiple opioid agents	1.05	0.95–1.16
Comorbidities
Alcoholism	0.92	0.68–1.23
Cocaine use	3.74	0.99–14.1
Marijuana use	1.15	0.33–4.02
Fibromyalgia	1.21	1.06–1.38*
Migraine	1.19	1.05–1.37*
Rheumatoid arthritis	1.42	1.21–1.67*
SLE	1.11	0.81–1.53
Back pain	1.27	1.16–1.39*
Tobacco use	1.21	1.08–1.36*
Substance abuse	1.19	0.85–1.66
Comorbidity score	1.02	0.99–1.05
Medications
Antidepressants	1.08	0.98–1.18
Benzodiazepines	1.43	1.30–1.57*
NSAIDs/Coxibs	1.00	0.91–1.09
Oral steroids	1.02	0.93–1.12
Gabapentin/pregabalin	1.11	0.93–1.32
Healthcare Utilization
No. of acute hospitalizations	0.93	0.86–1.00*

^aAdditionally adjusted for the index year

OME: oral morphine equivalent, NSAID: non-steroidal anti-inflammatory drug, Coxib: selective cyclooxygenase-2 inhibitor, PDC: proportion of days covered, SLE: systemic lupus erythematosus

^*P-value <0.05