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Do kids need statins or just a healthier diet?

If you read last week's headlines, you might be wondering if your eight-year-old should be taking a statin drug to lower his blood cholesterol and ward off heart disease in adulthood.

Recommendations released on July 7 by the American Academy of Pediatrics (AAP) to screen certain kids for cholesterol starting at age 2 and to treat those with high levels using a statin drug as early as age 8 have sparked debate among parents and physicians.

Statin drugs - such as Lipitor, Zocor, Mevacor, Pravachol and Crestor - work by blocking the action of a liver enzyme that promotes cholesterol production. This depletes cholesterol in cells, causing it to be removed from the bloodstream.

Cholesterol is needed to maintain cell membranes and nerve sheaths, form sex hormones and produce bile acids that aid digestion. Excess cholesterol in the blood, however, can build up on artery walls and, over time, cause them to become narrowed, which increases the risk of heart attack and stroke.

While experts deem statins as safe and effective in children as in adults, others argue there are no long-term data to prove that lowering a child's cholesterol will ward off a heart attack later in life. (Clinical trials have demonstrated the ability of statins to prevent heart attacks in men with elevated cholesterol and in members of both sexes who already have heart disease.) And no one knows the side effects of taking these drugs for 40 or 50 years.

To lower a child's future risk of heart disease, the AAP now recommends measuring blood cholesterol in kids and teenagers who have a family history of high cholesterol or early-onset heart disease - defined as 55 or younger for men and 65 years or younger for women. It's also advised that children for whom a family history is unknown, who are overweight, and who have high blood pressure or diabetes also be screened after age 2, and no later than age 10.The report recommends measuring total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides, and if they are within the desirable range, retesting every three to five years.

This might sound aggressive, yet it's well established that the process of heart disease begins in childhood and that it's progressive. One study of young people who died of accidental causes found fatty streaks in the coronary arteries of 50 per cent of children and 69 per cent of young adults. The extent to which arteries were covered by fatty build-up was shown to increase with age.

Elevated LDL cholesterol is a major risk factor for heart disease. LDL cholesterol is often referred to as "bad" cholesterol because too much of it in the bloodstream causes the buildup of fatty plaques on artery walls. Studies have shown that a substantial proportion of kids with high cholesterol - 70 to 75 per cent - continue to have elevated cholesterol in young adulthood.

The new guidelines recommend doctors consider statin therapy in children 8 or older who have an LDL cholesterol reading of 4.9 mmol/L (millimoles per litre) or higher, or 4.1 mmol/L for children with either a family history of early heart disease or at least two risk factors for heart disease, such as obesity and high blood pressure. Statins should also be considered for kids who have diabetes and an LDL cholesterol reading of 3.35 mmol/L or greater.

The Canadian Paediatric Society does not have a position on the use of statins in children, but Canadian doctors will undoubtedly take note of the U.S. guidelines and treat on an individual basis.

To date, a handful of clinical trials lasting 12 weeks to two years have demonstrated the ability of statins to lower LDL cholesterol in children by as much as 41 per cent. (Only one study used a statin drug - Pravachol - in kids as young as 8.) Over the short term, these trials have found statins do not effect growth, maturation or hormone levels in children.

While there's no evidence that taking a statin drug from a young age will reduce the risk of developing heart disease later in life, research does suggest these drugs improve blood vessel function in children with high cholesterol.

The majority of children with high LDL cholesterol have familial hypercholesterolemia, a genetic disorder not related to obesity, in which LDL cholesterol cannot be removed from the blood and builds to very high levels. People with familial hypercholesterolemia (about 1 in 500) tend to develop heart disease during early to mid adulthood. For these children, medication is necessary to bring LDL cholesterol down to a safe level.

But not all kids need medication to control their blood cholesterol and these guidelines should not detract from lifestyle modifications such as changes in diet and exercise.

The report recommends that all children - with or without high cholesterol - make appropriate dietary changes and increase physical activity. The American Heart Association, in its 2007 statement, recommends considering drug therapy only after a six- to 12-month cholesterol-lowering diet has failed.

Studies in children suggest that replacing saturated fat (found in fatty meats and high-fat dairy products) with unsaturated fats (found in vegetable oil, non-hydrogenated margarine, nuts, avocado) can lower LDL cholesterol by 15 per cent. Supplementing with DHA, an omega-3 fatty acid found in fish, may also improve blood cholesterol. Research has also shown that eating a psyllium-enriched breakfast cereal can also lower LDL cholesterol in kids.

The AAP's guidelines focus on reducing LDL cholesterol. But given the fact that one in four Canadian kids are overweight or obese, the combination of low HDL (good) cholesterol and high triglycerides (a blood fat) may be more prevalent than high LDL cholesterol. In these kids, weight loss through dietary changes and regular moderate exercise - not statins - is the primary treatment.

If your child has high LDL cholesterol, the need to medicate with a statin drug is a decision that must be made after discussing the risks and benefits with your child's physician.

Next week: Dietary strategies to help lower cholesterol in children.

Leslie Beck, a Toronto-based dietitian at the Medcan Clinic, is on CTV's Canada AM every Wednesday. Her website is lesliebeck.com.