Post-Surgery Opioid Refills Increase Risk of Household Misuse, Chronic Use

Denis Agniel, PhD

Opioid prescription refills following surgery is associated with increased household misuse and chronic use risks, according to new research.

A team of investigators reported an approximate 20% increased hazard of opioid misuse among family members for each refill of an opioid prescription for surgical patients. The findings illuminate the particular risks of proximity and availability of such addictive drugs in outpatient settings.

Led by Denis Agniel, PhD, of the RAND Corporation and Harvard Medical School department of biomedical informatics, a team of US investigators sought to interpret the link between postsurgical initiation of prescription opioid use among patients naïve to the drug class, and the subsequent risk of prescription opioid misuse and chronic opioid use among family members.

Since the COVID-19 pandemic, the US has observed a severe rise in opioid-related adverse events, nonfatal overdoses, and health care spending due to the rising burden. Agniel and colleagues suggested over-prescription of opioids in settings such as post-surgical outpatient care may be a key factor.

“Between 67% and 92% of patients who have surgery have leftover opioids, and 42% to 71% of pills are left unused after surgery,” investigators wrote. “Longer durations and higher total doses of these postsurgical prescriptions are associated with the risk of subsequent opioid misuse. Evidence suggests that ambient exposure to opioids within households confers risks as well, even on individuals who were not directly prescribed the opioids.”

The team conducted a cohort analysis of administrative data from US commercial insurer provider information including 35 million individuals. The observed participant population included pairs of patients who underwent surgery from 2008 – 2016, and family members living in the same household at the time. Investigators used a probability-weighted Cox proportional hazard regression model to calculate risk of opioid misuse and chronic opioid abuse among patients and their family members.

A total of 843,531 eligible patient pairs and family members were included in the final cohort. More than 52% of patients were female; a similar rate of family members were male. Nearly 30% of all pairs included patients aged 45 – 54 years old; 37.2% of family members were 15 – 24 years old.

Agniel and colleagues observed 3894 (0.5%) opioid misuse events and 7485 (0.9%) chronic misuse events among family members. The adjusted increased risk of opioid misuse among family members with each additional opioid prescription refill for post-surgery patients was 19.2% (95% CI, 14.5 – 24.0). That said, opioid misuse risk was observed to only increase in households with patients who received a prescription refill.

The adjusted increased risk of opioid misuse among family members in households with any prescription refill was 32.9% (95% CI, 22.7 – 43.8). In instances when post-surgery patients became chronic users themselves, the risk of opioid misuse among other family members increased more than 2-fold (hazard ratio, 2.52; 95% CI, 1.68 – 3.80).

“We estimated the highest risk and increase in risk of opioid misuse among younger people, whereas we found the opposite association for chronic opioid use,” investigators wrote. “Risk of chronic opioid use was highest among older family members, whereas risk of opioid misuse was greatest among younger family members.”

The team concluded that continued opioid prescriptions to patients after surgery were linked to increased risk of both chronic use and misuse among family household members. They identified 3 unique causes of such risks: diversion of unused opioids, extended familial exposure, or shared genetic or environmental factors of prescription refills.

“Further research into these household associations is necessary to clarify their contributions and many other possible mechanisms underlying the findings of this study,” investigators wrote. “Patient-level consumption and reported outcomes data would provide a more granular view of the association between opioid use and misuse as well as some insight into the amount of prescribing prompted by patient opioid requests rather than surgeon prescribing behavior.”

The study, “Association of Postsurgical Opioid Refills for Patients With Risk of Opioid Misuse and Chronic Opioid Use Among Family Members,” was published online by JAMA Network Open.