PhD Student University of Waterloo Kitchener, Canada
Background: Due to an increased risk of cardiovascular morbidity and mortality among patients with type 2 diabetes (T2DM), the use of statins for primary prevention may be recommended. However, the degree of benefit varies based on cardiovascular risk factors, including age and sex.
Objectives: We aim to conduct a quantitative benefit-risk analysis to determine the expected risk above which statins provide net benefit among patients with T2DM, without prior history of cardiovascular events, on low/moderate dose statins.
Methods: We used the Gail/National Cancer Institute method to produce a benefit-risk balance index indicating the absolute difference between the number of cardiovascular events, cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, unstable angina or revascularization, prevented (benefit outcome), and myopathy events caused (harm outcome). We calculated the balance index across a 10-year cardiovascular risk of 1 to 25%. Treatment effect and uncertainty were obtained from a meta-analysis of RCTs (benefit outcome) and observational studies (harm outcome).
Results: For males, statins demonstrated a net benefit at a 10-year cardiovascular risk of 3%, while the risk threshold for females was higher at 4-5%. A sensitivity analysis using the upper 95% confidence interval for the input parameters (benefit/harm outcomes, baseline risk and outcome preferences) increased risk thresholds for males by 2% and females by 3% from the primary analysis.
Conclusions: Most patients with T2DM and low 10-year cardiovascular risk will benefit from statins, however this varies by sex and age. This tool will guide clinicians to individualize recommendations and implement a shared decision-making approach with patients.
