Table 3:

Unadjusted comparisons of outcome rates in the 1 year before and after cohort entry*

Health care utilizationClients in SOS program (n = 82)Matched unexposed individuals (n = 303)
1 year before cohort entry1 year after cohort entryNegative binomial RR (95% CI)p value1 year before cohort entry1 year after cohort entryNegative binomial RR (95% CI)p value
N (rate per person-year)N (rate per person-year)
Primary outcomes
No. of ED visits250 (3.09)170 (2.12)0.69 (0.53 to 0.90)0.007591 (1.98)550 (1.86)0.94 (0.79 to 1.13)0.5
No. of hospital admissions74 (0.91)34 (0.42)0.46 (0.29 to 0.74)0.00198 (0.33)95 (0.32)1.02 (0.75 to 1.38)0.9
No. of hospital admissions for any incident infection26 (0.32)13 (0.16)0.51 (0.27 to 0.96)0.0430 (0.10)21 (0.07)0.72 (0.45 to 1.17)0.2
 Incident infective endocarditis≤ 5≤ 5NENE≤ 5≤ 5NENE
 Incident spinal infection, discitis, osteomyelitis or septic arthritis10 (0.12)≤ 5> 0.0515 (0.05)9 (0.03)0.61 (0.35 to 1.06)0.08
 Incident skin and soft-tissue infections14 (0.17)7 (0.09)0.51 (0.22 to 1.14)0.112 (0.04)11 (0.04)0.93 (0.44 to 1.96)0.8
Total health care costs not related to primary care or outpatient medications ($ per person)§15 6357310NE0.00283166527NE0.7
Secondary outcomes
Mental health ED visits or admissions34 (0.42)28 (0.35)0.84 (0.45 to 1.54)0.6155 (0.52)92 (0.31)0.60 (0.42 to 0.87)0.007
No. of opioid-related ED visits or admissions10 (0.12)≤ 5> 0.0518 (0.06)21 (0.07)1.18 (0.52 to 2.68)0.7
No. of any substance use disorder-related ED visits or admissions20 (0.25)20 (0.25)1.02 (0.56 to 1.83)1.088 (0.29)50 (0.17)0.58 (0.36 to 0.94)0.03
All-cause mortalityNA≤ 5NANA7 (0.02)NA
Opioid-related deathsNA0NANA≤ 5NA
Total publicly funded medication costs ($ per person)12 84021 119NE< 0.00161626861NE1.0
Costs for hydromorphone and opioid agonist therapy ($ per person)10803128NE< 0.00117191626NE0.02
  • Note: CI = confidence interval, ED = emergency department, NE = not estimable, NA = not applicable as all individuals were alive on their index date, RR = rate ratio, SOS = safer opioid supply.

  • * Each year represents the 360 days before and after cohort entry to align with the 30-day windows.

  • p value from negative binomial model for all noncost outcomes. p value for cost-related outcomes from Wilcoxon signed rank test.

  • Censored according to privacy requirements for cell sizes smaller than 6. p value and RR also suppressed to avoid residual disclosure.

  • § Excludes costs for primary care and costs of medications dispensed from community pharmacies.

  • Among public drug beneficiaries only (n = 71 clients of SOS program, and n = 262 matched unexposed individuals).