Table 3.

Adjusted risk ratios from the final multivariable model for enrollment in opioid agonist therapy within 6 months of index event among Medicaid recipients in Rhode Island, July 2013 – June 2018 (N = 17,449)^*

Characteristic	Adjusted risk ratio (ARR) (95% CI)
Age, years†
30–39	1.00 (0.99, 1.01)
≥60	0.94 (0.89, 0.99)
Prior diagnoses
Anxiety	0.75 (0.71, 0.78)
Depression	0.92 (0.89, 0.97)
Any other mental illness	0.80 (0.75, 0.84)
Mental health treatment (inpatient or outpatient)	0.85 (0.80, 0.89)
Alcohol use disorder	0.56 (0.52, 0.60)
Substance use disorder (non-opioid)	0.76 (0.73, 0.80)
Back problems	0.58 (0.55, 0.61)
One or more prior overdose	0.33 (0.28, 0.38)
Health care utilization
PCP visits above 75th percentile	1.03 (1.01, 1.04)
ED visits above 75th percentile	1.31 (1.28, 1.34)

PCP = primary care provider; ED = emergency department; OUD = opioid use disorder

^*Index event was defined as a patient’s initial opioid overdose or diagnosis of OUD between July 2013 and June 2018.

^†As compared to those who did not belong to a given age category.