The impact of over-the-counter simvastatin on the number of statin prescriptions in the United Kingdom: a view from the General Practice Research Database.

ABSTRACT

PURPOSE: The United Kingdom (UK) government changed the prescription policy of statins, making low-dose simvastatin (10 mg) available as an over-the-counter (OTC) drug in August 2004. We assessed the impact of this policy change on statin prescribing. METHODS: We examined all statin prescriptions in the General Practice Research Database (GPRD), a well-validated database of approximately 3.5 million patients, from the first quarter of 2001 to the second quarter of 2005. RESULTS: From 2001, the number of statin prescriptions written for GPRD patients was increasing by approximately 437 prescriptions per 100,000 people per quarter until the time of the policy change. Over the four quarters post-policy implementation, however, this trend changed abruptly (p < 0.0001) with a decrease of 281 prescriptions per 100,000 people per quarter. This decrease was not restricted to prescriptions of 10 mg statins but was also observed for statin prescriptions of >or=20 mg. Several other cardiovascular medications displayed a similar trend as that observed in the number of statin prescriptions. This trend was not observed among non-cardiovascular control medications. CONCLUSIONS: Our study suggests that the policy allowing the OTC sale of 10 mg simvastatin has had a significant impact on statin prescriptions by general practitioners. However, this new policy may also be leading to less aggressive statin therapy. An alternative explanation for the observed decrease in statin prescriptions may be related to the unknown factors responsible for the overall decrease observed with other cardiovascular prescription drugs.