Optimal risk thresholds for prescribing statins as primary prevention of cardiovascular disease in Iranian general population: a benefit-harm modelling study

The use of statins for the primary prevention of cardiovascular diseases (CVD) is associated with various beneficial outcomes, alongside certain undesirable effects. This study aims to determine optimal risk thresholds above which statin therapy yields a net benefit, considering both the positive effects and potential adverse effects, as well as their probabilities and patient preferences. Quantitative benefit-harm balance modeling was applied to the Iranian general population aged 40 to 75 years with no history of CVD. The analysis utilized data from prior studies, including statin effect estimates for different outcomes from a meta-analysis, patient preferences obtained from an Iranian survey, and baseline incidence rates of adverse outcomes sourced from the Global Burden of Disease study for Iran. Outcomes were defined as angina, myocardial infarction, fatal coronary heart disease, fatal or non-fatal stroke, and heart failure. Benefit-harm balance indices were calculated for various combinations of age, sex, and 10-year CVD risk. Statin therapy was found to be advantageous at a lower 10-year CVD risk threshold in men (18-23%) compared to women (24-28%). Furthermore, individuals aged 40-45 years exhibited a lower risk threshold (18% in men, 24% in women) than those aged 70-75 years (23% in men, 28% in women). The desirable 10-year risk thresholds for statin prescription in the primary prevention of CVD vary by age and gender, ranging from 18 to 28%, encompassing a spectrum of outcomes from angina to CVD mortality. These results suggest hard-CVD risk thresholds of 7.5% to 10% for both sexes.