Drug costs associated with non-adherence to cholesterol management guidelines for primary prevention of cardiovascular disease in an elderly population: The Rotterdam Study

Background: In The Netherlands, costs of HMG-CoA reductase inhibitor (statin) use have recently increased sharply compared with costs of other drugs. However, several studies have established both undertreatment and non-guidelines-indicated treatment with statins, suggesting a suboptimal use of resources. Objective: To estimate the drug costs associated with non-guidelines-indicated treatment and undertreatment with statins in an elderly population. Patients and setting: Data were obtained from the Rotterdam Study, a population-based prospective cohort study which began in 1990 with 7983 participants aged ≥55 years. Subjects with a history of cardiovascular disease (CVD) were excluded. Pharmacy records were used to assess patterns of medication use in daily medical practice. Main outcome measure: Non-guidelines-indicated treatment and undertreatment with statins were established in relation to Dutch cholesterol management guidelines for all participants. We calculated the costs of statin therapy associated with non-guidelines-indicated treatment, and the costs of statins if all those undertreated were to receive statins. The results were projected on to the Dutch population to determine the economic implications of non-adherence to cholesterol management guidelines in the elderly. Results: Of the participants who started treatment with statins for the primary prevention of CVD during follow-up, 69% received non-guidelines-indicated treatment. More men (7.5%) were undertreated than women (1.6%) and more women (6.2%) received non-guidelines-indicated treatment than men (1.5%). Among the participants without CVD who were still alive at 1 January 2002, 14% were eligible for statin therapy but were untreated. After projection of the prevalence of non-guidelines-indicated treatment and undertreatment to the Dutch population, the absolute costs for non-guidelines-indicated treatment with statins in 2005 were estimated to be approximately €23 million (uncertainty limits [UL]: €19-28 million), while the cost to eliminate undertreatment was also €23 million (UL: €19-28 million). Conclusion: Reallocation of resources used for statin therapy from those receiving non-guidelines-indicated treatment to those being undertreated could lead to a more efficient use of resources.