North Carolina’s Health and Human Services published a most interesting data set recently: http://www.ncdhhs.gov/divisions/mhddsas/ncdcu/Prescription-Rates-by-County
This interactive map shows information, by county, of the prescribing rates for opioids, benzodiazepines, and stimulants for the years 2012 through 2015. It also includes the average morphine milligram equivalents, or MMEs.
This data was gleaned from my state’s prescription monitoring program, called the North Carolina Controlled Substance Reporting System, abbreviated NC CSRS.
Quantifying MMEs, sometimes also called MEDDs, for morphine equivalent daily dose, is a way to quantify the potency of the opioids being prescribed. For example, since fentanyl is so potent that it’s prescribed in micrograms rather than milligrams, a prescription of 10mg of fentanyl would be very different than a prescription of 10mg of hydrocodone. So using MMEs, prescribed opioids are “translated” into the potency of that dose if it were morphine.
This data is important, since the risk of opioid overdose death risk increases when patients are prescribed higher MMEs. The Centers for Disease Control and Prevention (CDC) has said MME doses higher than 50mg per day should be used with great caution, since doses above this cut off are associated with higher risk of opioid overdose death.
I looked at my own county first, and found some puzzling data. For 2015, Wilkes County was fifteenth out of one hundred counties for the number of opioid pills prescribed per resident. The table said county residents were prescribed one hundred and two opioid pain pills per resident, giving an average of 1.3 opioid prescriptions per resident.
But when I looked at the 2012 data, Wilkes County averaged eighty-two pills per resident, giving an average of 1.1 opioid prescriptions per resident. In other words, the data showed more pills are being prescribed in 2015 than in 2012.
A new pain clinic opened in late 2014, which could explain some of this data. Also, since this is data collected by the patient’s county of residence, perhaps county residents travel to physicians in other counties for prescriptions, and then bring them to Wilkes County to fill.
Then I looked at the MME, the abbreviation for morphine milligram equivalents.
Wilkes County was number one out of one hundred NC counties for highest total morphine milligram equivalents. That says our county’s residents are prescribed more opioid firepower per capita than any other county in the state.
Really? This data doesn’t feel right to me. My impression from the new patients I admit to the opioid treatment program is that area physicians are prescribing lower doses than in the past.
So I started thinking…the opioid addiction treatment program where I work has been growing, accepting more patients, and our census is a little higher than one year ago. But data from my opioid treatment program is not part of the prescription monitoring data, because we must adhere to a higher standard of confidentiality, given the stigma attached to medication-assisted treatment of opioid use disorders.
Except for the office-based buprenorphine patients. At present, they are not protected by higher levels of confidentiality and their data is part of the prescription monitoring program. I only have thirteen patients in that program in Wilkes County, but the pain clinic also prescribes much buprenorphine, for both pain and addiction.
Buprenorphine is an odd drug, since it is a partial opioid agonist with a ceiling effect at 16-24mg per day.
The American Society of Addiction Medicine published a paper giving instructions about how to calculate MME for methadone and buprenorphine. Their position paper on this issue (http://www.asam.org/docs/default-source/public-policy-statements/public-policy-statement-on-morphine-equivalent-units-morphine-milligram-equivalents.pdf?sfvrsn=0 ) says,
- When used for the treatment of addiction, methadone and buprenorphine should be explicitly excluded from legislation, regulations, state medical board guidelines, and payer policies that attempt to reduce opioid overdose-related mortality by limiting milligram morphine equivalents (MME). Higher MME of these medications are necessary and clinically indicated for the effective treatment of addiction involving opioid.
- State medical boards should not use MME conversions of methadone or buprenorphine dosages used in addiction treatment as the basis for investigations or disciplinary actions against prescribers.
In other words, when buprenorphine is used to treat addiction, translating the dose into MMEs is misleading. I would add that given the ceiling effect of buprenorphine, a partial opioid agonist, overdose is much less likely with this drug than with full agonists for opioid-tolerance people. And really, the risk for overdose death is the purpose for collecting MME data.
My state’s prescription monitoring program does use MMEs for buprenorphine. I’ve seen it on my office-based patient reports, and it annoyed me, knowing ASAM’s position statement about this issue. But I didn’t realize using MMEs for buprenorphine could potentially skew data until now.
What if residents of my county are prescribed more buprenorphine than other counties, both because it’s being prescribed appropriately for the high incidence of opioid use disorder in the county, and also because at least one physician group prescribes buprenorphine off-label for pain?.
To get an idea of how badly buprenorphine MMEs could skew data, I went back and looked at one of my office-based patients. The NC CSRS (our state’s prescription monitoring program) gave a MME of 360mg for a buprenorphine dose of 12mg.
That’s misleading. Morphine at a daily dose of 360mg would place a patient at infinitely more risk than buprenorphine at 12mg.
Just a few days ago, I sent an email to some of the smartest people in my state, asking them to consider this issue. As I was getting ready to post this, I heard back. The NC CSRS plans to separate office-based treatment data. I’ll update readers.