You wrote the prescription, but will it get filled?
Nearly 16% of antihypertensive prescriptions in this study went unfilled. Managed care denials played a big part, but a third of the time patients didn’t pick up medications. E-prescribing feedback could help reverse these rates.
Purpose Despite numerous studies on adherence, there is little research on the first-fill rate of antihypertensive prescriptions. Our study took advantage of the recent increase in electronic prescribing (e-prescribing) and used data from e-prescribing physicians to determine the first-fill failure rate of antihypertensive prescriptions and to assess which factors predict first-fill failure.
Methods This retrospective study reviewed claims from a Mid-Atlantic managed care organization (MCO). We included adult members with continuous medical and pharmacy coverage who were prescribed an antihypertensive in 2008 by an e-prescribing physician. First-fill failure occurred when the patient did not obtain the antihypertensive medication due to either a denial by the MCO or reversal by the dispensing pharmacist. (Pharmacists reverse claims when a patient fails to pick up a medication.) Multivariate regression analysis determined the clinical and demographic factors associated with failure to fill.
Results The cohort consisted of 14,693 antihypertensive prescriptions, prescribed by 164 e-prescribing physicians for 7061 unique members. There were 2289 out of 14,693 prescriptions (15.6%) that went unfilled, affecting 24.3% of patients. Of the prescriptions not obtained, 1466 (64%) were denied by the MCO and 823 (36%) were reversed. Significant factors associated with first-fill failure were new diagnosis of hypertension, new antihypertensive agent, higher co-payment, and enrollment in a health maintenance organization or preferred provider organization.
Conclusions Patients newly diagnosed with hypertension and those prescribed a new antihypertensive were at particularly high risk for not obtaining their medication. Because nearly a quarter of patients did not obtain their initial fill of an antihypertensive prescription, future research should determine efficient and cost-effective systems to address first-fill failure in primary care.
Poor patient adherence to medical directives—the main cause of unsuccessful efforts to control hypertension1—is often difficult to assess in daily practice and in research. A common example of nonadherence is the failure to fill new prescriptions or to refill existing ones. In measuring adherence to first-fill and refilled prescriptions, investigators have often relied on patient self-report.2,3 However, this means of evaluation may be biased. One study found that patients markedly overstated their adherence to antihypertensive regimens, when compared with adherence measured by prescriptions actually filled.4
Objectively determining the rate of first-fill failure (not obtaining the initial fill of a prescription) has typically been cumbersome, requiring time-consuming chart reviews, which is unrealistic for studying large populations. A more efficient way to collect these data is through electronic prescribing (e-prescribing)—the electronic transmission of prescription or prescription-related information between a prescriber, a dispenser, and a pharmacy benefit manager or health plan, either directly or through an intermediary service.5
Our study sought to extend previous knowledge of adherence by determining the rate of first-fill failure for antihypertensive agents prescribed by electronic means, as well as identifying the clinical and demographic factors most closely associated with that failure. We believe e-prescribing may offer a way to improve antihypertensive medication adherence, especially for particular subgroups of patients, by providing information on the patient’s formulary and fill status notification.
Methods
This retrospective study used administrative, medical, and pharmacy data from a Mid-Atlantic managed care organization (MCO) serving 3.3 million medical and 1.2 million pharmacy members. To be eligible for inclusion, a member had to have an antihypertensive agent prescribed by a physician using e-prescribing. Our assumption in reviewing only prescriptions written by e-prescribing physicians was that each prescription would have a corresponding claim. To recruit a minimum of 100 electronic prescribers, we began by surveying physicians who had prescribed the highest volume of antihypertensive medication during the first half of 2008. We faxed a survey to these physicians, and if we received no response, we followed up by phone. Our final sample of physicians comprised those who were e-prescribing at least 75% of the time before January 1, 2008.6
A pharmacy claims query identified all antihypertensive prescriptions from January 1, 2008 through December 31, 2008 that were coded as new (a new prescription for either a new agent or the same agent the patient had been taking) and were prescribed by our group of electronic prescribers. We excluded members (and their prescription claims) who were younger than 18 years on the date of their first prescription and those who were not continuously enrolled in the same medical and pharmacy benefit plan from July 1, 2006 through December 31, 2008.
For each prescription, 3 claim options were possible: paid, denied, or reversed.
A paid claim meant that the prescription was approved by the MCO for coverage and that the member obtained the medication.
A denied claim occurred when coverage for the prescribed product was refused by the MCO.
