Marijuana users are likely to report opioid misuse among adults over 50 years in representative sample of the United States (2002-2014)

Background: In the wake of the rising rate of prescription opioid misuse, there has been increased public health interest in the possibility that cannabis might help to curb or prevent opioid use disorder. Previous studies were limited to young adult marijuana use population. Little is known about whether in older adult population, marijuana use is associated with a different type of nonmedical use opioids. We examined the association between marijuana use and nonmedical prescription opioids dependence and use among older adults.

Methods: The National Survey on Drug Use and Health is a nationally U.S. representative cross-sectional survey. We analyzed data for 75,949 adults aged ≥ 50 who participated in the year 2002-2014.

Results: Within the overall population, 3.8% of the older adults reported past-year marijuana use (estimate 3.5 million older adults Americans). Past-year marijuana use was very common (25%-37%) among nonmedical opioid dependence respondents compared to those who did not report nonmedical opioid dependence and use (3.5%-3.7%). Past-year marijuana user was significantly associated with an increase in odds of reporting opioid dependence (AOR 9.6 95% CI = 5.8-15.7), and past-year nonmedical use opioids (AOR 6.4 95% CI = 5.2-7.8). Illicit drug heroin was the most prevalent nonmedical used opioid (AOR 6.3 95% CI = 5.0-7.9), compared to codeine (AOR 4.5 95% CI = 3.5-5.7), hydrocodone (AOR 4.9 95% CI = 3.8-6.4), methadone or tramadol (AOR 4.9 95% CI = 2.0-12.3).

Conclusion: Policymakers and healthcare providers should remain mindful that older adult marijuana users regardless of initial legitimate medical needs are likely to report nonmedical opioid use including illicit drug heroin.

Keywords: Marijuana; cannabis; nonmedical prescription; older adults; opioid.