Novel Measure of Opioid Dose and Costs of Care for Diabetes Mellitus: Opioid Dose and Health Care Costs

• In diabetes patients, total health care costs are significantly higher for opioid users.
• Costs per 6 months increased linearly with increasing daily and total opioid doses.
• A novel measure combining mean daily and total dose best discriminated higher costs.
• Total costs >$8,000 greater for 50–99 mg mean daily opioid dose and >900 mg total dose.
• Total costs also >$8,000 greater for ≥100 mg mean daily dose and >300 mg total dose.

Diabetes mellitus (DM) has well known costly complications but we hypothesized that costs of care for chronic pain treated with opioid analgesic (OA) medications would also be substantial. In a statewide, privately insured cohort of 29,033 adults aged 18 to 64 years with DM and noncancer pain who filled OA prescription(s) from 2008 to 2012, our outcomes were costs for specific health care services and total costs per 6-month intervals after the first filled OA prescription. Average daily OA dose (4 categories) and total dose (quartiles) in morphine-equivalent milligrams were calculated per 6-month interval after the first OA prescription and combined into a novel OA dose measure. Associations of OA measures with costs of care (n = 126,854 6-month intervals) were examined using generalized estimating equations adjusted for clinical conditions, psychotherapeutic drugs, and DM treatment. Incremental costs for each type of health care service and total cost of care increased progressively with average daily and total OA dose versus no OAs. The combined OA measure identified the highest incremental total costs per 6-month interval that were increased by $8,389 for 50- to 99-mg average daily dose plus >900 mg total dose and, by $9,181 and $9,958 respectively, for ≥100 mg average daily dose plus 301- to 900-mg or >900 mg total dose. In this statewide DM cohort, total health care costs per 6-month interval increased progressively with higher average daily OA dose and with total OA dose but the greatest increases of >$8,000 were distinguished by combinations of higher average daily and total OA doses.PerspectiveThe higher costs of care for opioid-treated patients appeared for all types of services and likely reflects multiple factors including morbidity from the underlying cause of pain, care and complications related to opioid use, and poorer control of diabetes as found in other studies.