鶹ýӰ

The (Unexpected) Compliance Trap

— When 90% medication adherence can be bad

MedpageToday

When I started working in a jail, I was surprised to find many important differences between the practice of medicine within a detention facility and "on the outs" (as inmates call it). Many of these I had to learn from sad experience. One of these is what I have come to call "The Compliance Trap." What I mean by this is that inmates are much more compliant with taking their medications when in jail than when they are at home. And this often results in important medical consequences -- patients can get hurt.

To explain why, I first need to briefly explain how medications work in a jail. As a strong general rule, we try to continue patients' outside medications when they come to jail -- hopefully with minimal disruption. If the newly booked inmate cannot bring their own medications to jail, we have a process of verifying what these prescriptions are and then ordering the medications from our own pharmacy.

Once the medications are received at the jail, nurses then dispense medications to inmates at regularly scheduled "med pass" times. Inmates are reminded to take their medications at every med pass when the deputies announce "med pass" over the loudspeaker in the dorm. The nurses know, of course, who comes to the med cart to receive their medications and who does not. In fact, the nurses are required to keep a log of all medication doses received and all medication doses missed. Noncompliant inmates typically are referred to the practitioner's clinic to discuss why they are not taking their medications.

The bottom line, of course, is that compliance with prescribed medications among jail inmates is often 90% or higher.

Compliance with prescribed medications in the free world is nowhere close to this. A recent in the Annals of Internal Medicine estimates overall patient compliance with prescribed medications at less than 50%.

This, then, is the Compliance Trap: jail patients are compliant with their medications in a way that they were not before coming to jail. And this can sometimes get them into trouble.

Take, for example, the patient who came to my jail with a prescription for an especially large dose of phenytoin (Dilantin), 600 mg a day (compared to a typical phenytoin prescription of 300 mg a day). However, 600 mg a day of phenytoin was a legitimate prescription for this patient -- from a prominent neurologist, no less -- and so the phenytoin was continued at the same dose in the jail. Within two weeks, however, the patient's phenytoin level was 32 mcg/dL (therapeutic 10-20 mcg/dL), and he had symptoms of dizziness and nausea attributable to phenytoin toxicity. Phenytoin 600 mg a day was, indeed, too big of a dose for this patient. In fact, after we had adjusted his dose and checked levels a couple of times, we found that the proper dose of phenytoin in this patient was a more modest 400mg a day.

So how did this happen? I did not interrogate this patient's outside doctor, but I think I know what happened. The patient kept returning to the neurology clinic with subtherapeutic blood levels of phenytoin! I can see his neurologist saying "We've got you on 500 mg of Dilantin a day, but your blood levels are still low! I guess we'd better go up to 600." The neurologist evidently did not recognize the possibility that the reason for the subtherapeutic blood levels was not that the patient was a super-rapid metabolizer of phenytoin, but rather that he just hadn't been taking his phenytoin regularly.

That is, until this patient came to jail. Then the jail nurses made sure that he did not miss any doses. And quicker than you can say "Compliance Trap," he was phenytoin toxic.

This phenytoin patient is one example, but there are several more. All of these are real examples from my jails. Remember, all of these dosages were verified as accurate when they arrived at the jail:

  • A 110-pound woman brings in a prescription for six lithium 300 mg tablets a day
  • A man with a history of DVT takes 15 mg of warfarin a day
  • 1,500 mg of valproate a day is prescribed to a woman with bipolar disorder
  • A man is prescribed 5,400 mg of gabapentin daily for seizures

Now, perhaps all of these are legitimate doses, carefully titrated based on blood levels in perfectly compliant patients. However, the wary jail practitioner could also easily fall into the Compliance Trap and end up with toxic patients. The only way to know for sure is to check appropriate monitoring levels a week, say, after they arrive in the jail.

(By the way, only one of the four examples above turned out to be a proper dosage based on careful monitoring. I'll leave it to you to guess which one!)

An interesting variation of the Compliance Trap has to do with insulin doses. Consider the man who arrives in jail taking 75 units of Lantus twice a day plus an equally large amount of regular insulin. The Compliance Trap here is that these large doses of insulin may be related to a diet that does not exactly conform to the American Diabetic Association ideal. At home, this patient may have a variety of snacks, from Snickers to Cheese Puffs to Chunky Monkey readily available. His daily caloric intake might routinely exceed 4,000 -- or even 5,000 -- calories.

However, once this man comes to jail, he cannot raid the refrigerator at 2:00 a.m. In jail (initially, at least), the only thing he will get to eat will be the 2,500-calories-a-day jail diet. If I were to give him all of the insulin he was taking on the outside, he could easily crash and burn.

I'm sure that every primary care physician has seen similar examples, for example, in patients transferred from other providers. It is just magnified in a jail setting due to the large number of patients shuffling through the system. So if you'll excuse me, I need to figure out why my newly booked patient is taking 350 mcg of levothyroxine.

Jeffrey E. Keller, MD, FACEP, is a board-certified emergency physician with 25 years of experience before moving full time into his "true calling" of correctional medicine. He now works exclusively in jails and prisons, and blogs about correctional medicine at .