The relationship between foster care entries and high-dose opioid prescribing in California

An important effect of the current opioid epidemic is on children whose parents are unable to provide appropriate care. We employ quarterly, county-level data for California for 2009-2016 to study the relationship between foster care entries and opioid misuse by their parents. Our linear regression analysis includes both county and time fixed effects and controls related to child removal risk. We improve on the limited existing research in the area by analyzing higher frequency data, examining a proximal measure of opioid abuse, and allowing for differential associations by urbanicity. We found a positive association between the rate of child removals and the rate of residents who were cumulatively prescribed a high dose of opioids (>90 morphine milligram equivalents (MMEs) per day) during the quarter. A one standard deviation in this rate is associated with a roughly 9% increase in the overall removal rate. We further found that the association between removals and high MMEs is especially pronounced in rural areas and largely not existent in urban areas. Our results provide a more precise estimate of the relationship between the potential for opioid misuse and child welfare.