What is the optimal age for starting lipid lowering treatment? A mathematical model
Current guidelines on drug treatment for heart disease don't advise doctors on how to treat young patients with a high risk profile, reports research in this week's BMJ. This is because the guidelines are based on who to treat, rather than on when to treat, inevitably shifting treatment to older age groups, where absolute risk - the chance of having an "event" such as a heart attack over a fixed period of time - increases.
But, say Vallance and colleagues from University College, London, the substantial proportion of young people with high blood pressure and high cholesterol levels might have a low absolute risk, but they have a high relative risk. This means that their chances of having an "event" are higher than someone with normal blood pressure and cholesterol levels. And, say the authors, these are the people, who, by the time they have reached the age at which they cross the official threshold for treatment with the expensive statin group of drugs, will have already accumulated most of their lifetime risk.
To solve the conundrum, the authors supply several mathematical models, based on proven formulas, which could help doctors predict the optimal age at which starting treatment would maximise the health benefits for each individual patient, and also the cost benefits to the NHS. Reducing the age at which treatment begins inevitably costs more - an additional £4000 per patient a year at the age of 40 and an additional £2000 per patient a year at the age of 50. But, say the authors, the additional costs would be set against the gains to be made from fewer hospital admissions and acute care and less time off work, to say nothing of quality of life.
Dr Aroon Hingorani, Centre for Clinical Pharmacology and Therapeutics, University College, London.
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