(160) Cost-Effectiveness of Statins in the Primary Prevention of Cardiovascular Disease in Older Adults: A 5-Year Retrospective Cohort Study

Background: Few studies have investigated the cost-effectiveness of statins in older adults in a real-world primary prevention setting. The existing ones have based their statin effectiveness data on sub-group analyses from RCTs. However, using data from RCTs in an economic evaluation may not reflect medications’ true efficiency profile in a real-world setting.

Objectives: The objective of the study was to assess the real-world cost-effectiveness of statins in the primary prevention of cardiovascular diseases (CVD) in older adults (>65 years old).

Methods: We conducted a retrospective cohort study to evaluate the cost-effectiveness of statin therapy over a 4-year time horizon. The patient cohort, comprised of 39,800 patients identified using Quebec claims data, was followed from April 1st, 2013, to March 31st, 2018. We will exclude individuals with any statin prescription in the year prior to the index date and those with any CVD history between April 1st, 2008 and March 31st, 2013 to include only new users of statins for primary prevention. Patients were considered exposed to statins if they persisted in the treatment for at least 3 months and not exposed if they failed to persist. The ICER between the two groups was measured in CAD2018 per life-years gained from a health system perspective, applying a discount rate of 1.5%. We will be using the inverse probability weighted (IPW) estimator to control for administrative censoring. We will thus reweigh each complete case so that each complete case represents not only itself but also a number of incomplete or censored cases. We will also be using IPW to control for baseline confounding.

Results: The use of statins in the primary prevention of CVD in adults aged >65 years old was found to be cost-effective compared to usually accepted thresholds, with an ICER of $2,949 per life-year gained. More precisely, adjusted mean costs for exposed patients were $11,774 compared to $11,917 for non-exposed patients, with adjusted average life-years per patient being 3.39 and 3.44 for exposed and non-exposed patients, respectively.

Conclusions: Study results suggest that, in patients >65 years old, statins could be a cost-effective solution in the primary prevention of CVD in older adults.