Even though statins might slightly raise the risk of a rare type of bleeding stroke, this tiny risk is more than canceled out by the big drop in common clot-based strokes and heart attacks.
Scientific Claim
Statin therapy does not increase the risk of haemorrhagic stroke in individuals with low vascular risk, and any potential small excess risk is outweighed by the reduction in ischaemic stroke and other vascular events.
Original Statement
“The present analyses suggest that the annual excess risk of haemorrhagic strokes per 1.0 mmol/L LDL cholesterol reduction might be of the order of 0.5 per 1000 people treated over 5 years... But, since statin therapy produced a clear reduction in overall stroke... such an increase in haemorrhagic stroke risk would typically be outweighed by the reduction in the risk of ischaemic stroke...”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
definitive
Can make definitive causal claims
Assessment Explanation
The study quantifies the potential risk and compares it to the larger benefit, concluding net benefit. The language is cautious yet definitive based on the data.
Evidence from Studies
Supporting (1)
The effects of lowering LDL cholesterol with statin therapy in people at low risk of vascular disease: meta-analysis of individual data from 27 randomised trials
This big study found that for people with low risk of heart problems, taking statins lowers their chance of having a stroke caused by blocked arteries—and doesn’t seem to increase the rare risk of bleeding in the brain. The good effects are much bigger than any tiny risks.