Effect of Lipid-Testing Interval on Stoke Risk among Newly Diagnosed Dyslipidemia Patients Initiated on Statins

(1) Background: Although current guidelines recommend regular lipid testing for dyslipidemia patients, the effectiveness of regular lipid profile monitoring in clinical outcomes is unclear. (2) Methods: We assessed 64,664 newly diagnosed dyslipidemia patients from the Korean National Health Insurance Service Health Screening Cohort from 2003–2011 For lipid-testing frequency from all admission and outpatient records for 3 years after diagnosis. Participants were followed until 31 December 2015 for stroke. We used Cox regression analysis to determine the adjusted hazard ratio (aHR) for stroke according to lipid-testing interval. (3) Results: Compared to patients with lipid-testing intervals of ≤6 months, patients with >6 to ≤12 (aHR 1.32, 95% confidence interval (CI) 1.08–1.61), >12 to ≤18 (aHR 1.48, 95% CI 1.20–1.82), and >18 (aHR 1.54, 95% CI 1.25–1.90) month testing intervals had elevated risk of total stroke (p for trend <0.001). A significant association existed between lipid-testing interval and total and ischemic stroke risk in the >6 to ≤12 (aHR 1.62, 95% CI 1.19–2.21), >12 to ≤18 (aHR 1.87, 95% CI 1.36–2.58), and >18 (aHR 1.79, 95% CI 1.30–2.48) month interval groups, but no significant association existed between lipid-testing interval and hemorrhagic stroke risk. (4) Conclusions: Lipid-testing intervals of more than 6 months may lead to increased stroke risk among newly diagnosed dyslipidemia patients after initiation of statin treatment. Lipid testing every 6 months can lower stroke risk among dyslipidemia patients.