Potentially Unsafe Chronic Medication Use Among Older Adult Chronic Opioid Users

To assess chronic potentially unsafe medication use among older adults using opioids chronically versus those who did not, to assess the likelihood of chronically using medications to treat adverse effects associated with chronic opioid use, and to characterize the differences in chronic potentially unsafe medication use at three morphine equivalent dose (MED) levels/day (less than 50MED, 50-90MED, and more than 90MED).

Retrospective cross-sectional analysis.

Prescription claims data from a national telehealth Medication Therapy Management (MTM) provider for the year 2015.

All Medicare Part D beneficiaries (65 years and older [older adults]) from one Medicare Part D plan provider in one state who were eligible to receive MTM services.

Medication claims were limited to refills in a 120-day window from one Medicare Part D provider. Chronic medication use was defined as having a total days' medication supply of 84 days or more. Odds ratios (ORs) and χ² tests were used to compare chronic medication use among beneficiaries who were chronic opioid users versus nonopioid users. Analyses were repeated among chronic opioid users at the less than 50MED, 50-90MED, and more than 90MED levels. Unpaired t tests and Welch's analysis of variance paired with Games-Howell post hoc tests were used for continuous variables. Older adult (mean age 76 years) chronic opioid users were more likely to use muscle relaxants chronically (OR 2.67, 95% confidence interval [CI] 2.20-3.25), benzodiazepines (OR 2.08, 95% CI 1.87-2.31), hypnotics (OR 1.98, 95% CI 1.67-2.34), antidepressants (OR 1.64, 95% CI 1.51-1.77), and nonsteroidal antiinflammatory drugs (OR 1.78, 95% CI 1.59-1.98) versus nonopioid users. Further, chronic opioid users were 3.04 times (95% CI 2.05-4.51) more likely to use muscle relaxants and benzodiazepines concomitantly chronically and also more likely to use medications chronically to treat gastrointestinal reflux disease, constipation, estrogen loss, nausea and vomiting, and edema. Very high-dose (more than 90MED/day) chronic opioid users were more likely than low-dose users (less than 50MED) to use antidepressants (OR 1.51, 95% CI 1.15-1.97, p=0.003).

Older adults with chronic opioid use were more likely to use potentially unsafe medications chronically. These data demonstrated discordance between national prescribing guidelines and real-world practice among older adults with chronic pain in one Medicare Part D plan.