Patients enrolled in a consumer- directed health plan (CDHP) have significantly lower medication adherence rates, compared with individuals enrolled in traditional health plans, according to a new analysis by Medco Health Solutions Inc.

The analysis reviewed the pharmacy claims of >14,000 insured individuals who chose a CDHP in 2006 after being in a health plan without a deductible in 2005. The participants were being treated for hypertension, hyperlipidemia, or diabetes.

The researchers analyzed both adherence to the prescribed duration of therapy and adherence to the therapy regimen as prescribed by the physician. Persistency and compliance rates among the control group changed little between 2005 and 2006. In 2006 when the study group switched to a CDHP, their persistency and compliance rates dropped from 2005, compared with the control group. The study group's compliance rates decreased 5% for both hypertension and diabetes, and 9% for hyperlipidemia from 2005 to 2006.

"This study provides further evidence that placing greater responsibility and costs on consumers requires an increased level of support and education to ensure patients remain adherent to their medication therapy," said Tracy Grunsfeld, vice president of consumer solutions at Medco.