Suboptimal use of statin therapy in elderly patients with atherosclerosis: A population-based study

Background

Current evidence suggests that statin use plays an important role in improving adverse cardiovascular outcomes in patients with atherosclerosis. However, limited population-based data are available on use of statin therapy in these patients in Canada. We sought to study trends in statin use to treat these patients in Ontario during a 10-year period.

Methods

We conducted a population-based cross-sectional time series analysis between April 1, 1995, and March 31, 2004, using health care data from Ontario, Canada.

Results

During the study period, 343,154 elderly patients with atherosclerosis were identified. Of these, 235,615 (68.7%) had coronary artery diseases (CAD), 115,012 (33.5%) had cerebrovascular disease (CVD), and 23,886 (7.0%) had peripheral arterial disease (PAD). About 46% were women, and mean patient age was 77.1 (SD, 7.5) years. During the study period, the percentage of patients treated with a statin in each group increased considerably, from 9.8% to 55.3% in all atherosclerotic patients (P < .01), from 11.8% to 61.2% in CAD patients (P < .01), from 5.3% to 41.2% in CVD patients (P < .01), and from 6.8% to 43.3% in PAD patients (P < .01). During the entire study period, the percentage of statin users was lowest among PAD and CVD patients, followed by patients with both a history of PAD and CVD.

Conclusion

The use of statin therapy in elderly patients with symptomatic atherosclerosis has increased substantially during the past decade, but many patients remain untreated. The suboptimal use is greatest among patients with PAD or CVD, or both, and lowest in patients with CAD. Given the heightened risk of cardiovascular adverse outcomes in patients with atherosclerosis, these data have important and immediate implications.