About half of Medicare beneficiaries under age 65 received an opioid prescription in 2014, according to the new research by Chao Zhou, PhD, and colleagues at the Centers for Disease Control and Prevention.
‘The high level of opioid prescription as the report suggests is potentially linked to the factors such as economical conditions or the differences in medical practices, which may all depend on low income inequality.
They find that opioid prescribing for disabled adults is higher outside of "large central metro" counties"even after accounting for local economic factors.
County-Level Factors Influence Opioid Prescribing in Under-65 Adults on Disability
The researchers analyzed data on nearly 3.5 million adults younger than 65 who were medically disabled, without cancer, without end stage renal disease, not receiving hospice care and receiving Medicare Part D (prescription drug) benefits for at least 12 months in 2014.
Most Medicare beneficiaries under age 65 are Social Security Disability Insurance (SSDI) recipients.
Dr. Zhou and colleagues analyzed measures of opioid prescribing by county, including demographic and geographic variations. They also looked at how local economic factors household income, unemployment rate, and income inequality (Gini index)affected opioid prescribing.
About half of the study population (49 percent) had at least one opioid prescription during 2014. More than one-fourth (28 percent) were long-term opioid users, with six or more prescriptions.
The proportions of opioid prescriptions were higher for women versus men; for White and Native American beneficiaries, compared to other racial/ethnic groups; and for subjects aged 55 to 64 years, compared to younger groups.
Analysis of county-level differences showed more than just an urban/rural divide. Rather, "large central metro" counties (inner-city) had lower opioid prescribing than all other classifications including "large fringe metro" (suburbs), "micro-politan" (small cities), and "non-core" (rural) areas.
"Large central metro areas were different from the rest of categories," Dr. Zhou and coauthors write. "Large fringe metro areas were similar to rural counties." Areas of more intensive opioid prescribing in the South, Southwest, and Midwest closely overlapped with "regions of economic hardship."
Confirming those associations, opioid prescribing was higher in counties with lower median household income and higher unemployment. Income inequality was also a significant factor, although the relationship was the opposite of expected: counties with higher income inequality had lower measures of opioid use.
"The metro/non-metro pattern of opioid prescribing was different from that of other health indicators such as smoking, cerebrovascular disease [stroke], and mortality," Dr. Zhou and colleagues add. They call for further studies to identify the "distinctive mechanism" explaining the higher opioid prescribing outside of urban areas.
Research is also needed to clarify the negative association with income inequality. The researchers suggest that low income inequality might be linked to other factors such as economic conditions or differences in medical practice that lead to higher opioid prescribing.
The study shows the very high rate of opioid prescribing to disabled, non-elderly Medicare recipients, and suggests that local economic factors are a major contributing factor. Efforts to understand the economic factors affecting opioid prescribing will require a "multi-pronged approach involving medical, behavioral health, and socioeconomic factors," Dr. Zhou and colleagues conclude.
"The opioid epidemic is part of a larger challenge primarily faced by white rural working-class Americans," Dr. Zhou comments. The new findings add to previous evidence that disabled persons in the SSDI program are "a particularly vulnerable segment of this demographic." Dr. Zhou believes that investment in economically depressed areas might be a helpful part of comprehensive approaches to battling the opioid crisis.