Higher Copayments for Diabetic Medication Predict Treatment Failure

A recent study reviewed the prescription and laboratory data for over 18,000 members of a health insurance plan who had been diagnosed with (and treated with medication for) diabetes. For every $10 increase in prescription copayment for a given drug, treatment failure risk (the chance that the medication would be discontinued or changed to another medication) increased by 26%. (Source: P & T Journal, September 2008)

While the headline for the article sounds impressive, the other findings that struck me as amazing were:

• only about 57% of prescriptions written were even filled
• initial treatment failed during the four year study period in 70% of patients
• adherence to medication (ie. filling the prescription and subsequent refills) predicted end-of-study blood sugar (for every 10% increase in adherence, there was about a 0.12% decrease in A1c)

I think that one of the best messages from this study was that a patient who is given a prescription for a medication without an explanation about how the medicine works and why it is being prescribed is unlikely to fill the prescription, particularly if the medication is expensive. And, not filling the prescription (or continuing with refills) certainly makes the medicine less effective! Doctors should take the time to explain to patients how a medicine works and why it is important - they're more likely to actually take it - and their health will improve as a result.

Written / Posted by Scott W. Yates, MD, MBA, MS, FACP