Rates and costs of drug testing practices for private payors in the outpatient setting in the United States, 2015-2019.

Introduction: Clinical practice guidelines recommend drug testing patients who are receiving opioids chronically for pain or medication for a substance use disorder (SUD)-particularly opioid use disorder (OUD)-but practices vary due to a lack of consensus on testing frequency during follow-up. This study aimed to evaluate rates and costs of outpatient drug testing practices for patients receiving opioids for chronic pain or medication for an SUD.

Methods: Using claims data from a large de-identified claims data warehouse, we conducted a retrospective cohort study of chronic opioid, buprenorphine, and naltrexone users between January 2015 and December 2019. We identified two cohorts-chronic opioid medication cohort (CO) and SUD-indicated medication cohort (SUD). We assessed drug testing rates during follow-up using procedure codes and costs using copayment, deductible, co-insurance, and out-of-pocket data.

Results: Among 6,657,515 eligible claimants, 367,118 (5.5 %) received opioids chronically and 73,303 (1.1 %) received an SUD-indicated medication. The cumulative proportion of drug testing during follow-up was similar between cohorts (CO: 36 %; SUD: 35 %), but rate of testing was consistently twice as frequent for the SUD cohort. All cost variables for the first drug test were higher on average in the SUD cohort than the CO cohort except copay: deductible (SUD: $18.54; CO: $7.33); co-insurance (SUD: $10.36; CO: $2.53); out-of-pocket (SUD: $29.39; CO: $10.57); copay (CO: $0.71; SUD: $0.49) (all p < 0.001).

Conclusions: Overall proportion of drug testing was similar between cohorts, but testing frequency was at least double during follow-up in the SUD cohort. Most cost variables were higher in the SUD cohort. Whether the high cost of drug testing is a barrier to medication use or is associated with treatment discontinuation should be evaluated.