A meta-analysis confirms that statin therapy lowers the risk of major vascular events by about a fifth among subjects with no history of vascular disease, male and female, young and old.
The findings were published on May 16 online in The Lancet.
The authors concluded, “The present report shows that statins are indeed both effective and safe for people with a 5-year risk of major vascular events lower than 10% who would typically not be judged suitable for statin treatment…and, therefore, suggests that treatment guidelines might need to be reconsidered.”
As background, the authors noted that while statin treatment is most widely used for patients with cardiovascular disease (CVD), it has been less clear if statins benefit those without CVD, even though at least half of all vascular events happen among the latter group.
Current guidelines in the USA, Europe, and the UK suggest statin therapy for people whose 10-year risk of a major vascular event is at least 20%.
In this study, the Cholesterol Treatment Trialists’ (CTT) collaborators conducted a meta-analysis of 175,000 individuals in 27 randomized trials to evaluate effects of lowering LDL cholesterol with statin therapy.
They grouped subjects into one of five baseline categories, according to 5-year major vascular event risk. They examined outcomes by comparing statin therapy versus no statin therapy, and higher statin dosing versus lower statin dosing.
They found that statin therapy lowered the risk of serious vascular events by 21% for each 1mmol/L reduction in LDL cholesterol in each of the 5 baseline risk groups, including the group with the lowest risk of vascular disease.
In groups with a 5-year risk lower than 10%, an already small risk was significantly lowered even in those without a history of vascular disease. This drop was due largely to the reduction in major coronary events and revascularisation surgeries. Notably, the proportional reduction in major vascular events in the two lowest risk categories was at least as large in the higher risk categories.
The authors wrote, “In individuals with 5-year risk of major vascular events lower than 10%, each 1mmol/L reduction in LDL cholesterol produces 11 fewer major vascular events per 1000 treated over 5 years, a benefit that greatly exceeds any known hazards of statin therapy.”
There was no evidence in the analysis that statin therapy increased cancer risk or death from other non-vascular causes.
In an accompanying Comment, Shah Ebrahim from the London School of Hygiene and Tropical Medicine and Juan P Casas from University College and the London School Hygiene and Tropical Medicine, London wrote, “Translation of the CTT findings into practice will require more affordable ways to identify individuals for treatment and keep them on optimal regimens. Because most people older than 50 years are likely to be at greater than 10% 10-year risk of CVD it would be more pragmatic to use age as the only indicator for statin prescription as originally proposed for the polypill. This approach would avoid the costs, ranging from £7 to more than £700 per patient screened, of vascular screening checks recently implemented in the UK.”