Home Am I at Risk? High Cholesterol - Page 2

High Cholesterol - Page 2

How does high cholesterol increase my risk of stroke?

Excess cholesterol that circulates in the blood can stick to the walls of arteries, and over time, this fatty plaque buildup will narrow the arteries. This can lead to a blocked-vessel stroke if it affects a main artery leading to your brain (carotid) or one of the smaller vessels inside your brain.

Will lowering my cholesterol help prevent stroke?

Taking a statin medication to lower cholesterol reduces the risk of both first-ever stroke and recurrent stroke. Among people at high risk for cardiovascular disease but with no history of stroke, statin therapy lowers blocked-vessel stroke risk by about 21%, but slightly increases the risk of hemorrhagic (bleeding) stroke.4 There is little data on the effect of statins on stroke risk in women in particular, but the reduction in LDL cholesterol associated with statin drug treatment appears to decrease the risk of major coronary events in both sexes and all age groups. A roughly 30% decline in coronary events has been seen in both men and women of all age groups taking cholesterol-lowering statin therapy.5

The largest risk reduction in blocked-vessel stroke has been seen with a specific statin medication—atorvastatin (Lipitor)—which reduced the risk of having a first stroke by 27% to 48% in two large studies.6

One of the largest studies to test the effects of statin therapy on stroke risk in patients who had already had a stroke, the SPARCL Trial (40% women) found that stroke patients taking atorvastatin had a 16% reduced risk of recurrent stroke. A 33% lower risk of blocked-vessel stroke was seen in patients who lowered their LDL cholesterol by more than 50%. This suggests that the reduction in stroke risk is due to the medication’s lowering of LDL cholesterol, and that there may be a continuous relationship between LDL cholesterol and stroke risk—the lower your LDL level, the lower your stroke risk.7

Atorvastatin may also lower risk of cardiovascular events (including stroke) in high-risk diabetic patients with high blood pressure. Among more than 2000 such patients in one study, atorvastatin lowered the risk of a cardiovascular incident by 25% to 48% when compared to placebo. In diabetic patients who had already suffered a cardiovascular event, atorvastatin reduced the risk of another stroke by 68% compared with standard care.8, 9

While atorvastatin is the most studied and proven cholesterol-lowering statin drug, some research suggests that other statins may work just as well at preventing heart disease and stroke by lowering cholesterol. These are pravastatin (Pravachol) and simvastatin (Zocor).10 Simvastatin is available in generic form, and is thus a cheaper option than the others.10 Lipitor is one of the most expensive drugs on the market, but if your doctor prefers it, it may be because there is some evidence it works better at reducing risk of a first stroke compared with pravastatin.6

Do cholesterol levels affect stroke risk equally in women and men?

A recent study of 6000 Chinese people (56% were women) aged 35 and older suggests that cholesterol levels may affect stroke risk differently in men and women. In this study, high LDL (bad) cholesterol was associated with a roughly 40% increased stroke risk for both women and men. However, women were more likely to suffer a blocked-vessel stroke if they had high total cholesterol or a high ratio of total cholesterol to HDL (good) cholesterol. High total cholesterol increased stroke risk in women by 31%, and a high ratio of total cholesterol to HDL cholesterol increased it by 66%.11 Although further research is needed to confirm these results, in women HDL cholesterol may be a more important predictor of stroke than LDL cholesterol.

A study from Japan involving 4000 people (70% were women) found that low HDL cholesterol levels (below 30 mg/dL) were associated with over twice the risk of stroke for both women and men.12 High levels of HDL (as a percentage of total cholesterol) are associated with a wide range of beneficial cardiovascular effects, for both women and men, even where heart disease is already present.13

How can I lower my cholesterol?

The American Heart Association recommends lowering cholesterol levels through diet and exercise, in addition to medication if necessary. See our section on heart-healthy diet to learn about healthy foods, as well as our section on exercise to learn about the benefits of being active. You should speak with your doctor before starting any new regimen intended to affect your cholesterol numbers. He or she may prescribe cholesterol-lowering medication.

Next: Your Cholesterol Numbers

Filed in Am I at Risk? > Featured


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