When Dr. Ting Cai and her colleagues at the University of Oxford set out to understand why so many patients decline statins despite being at high risk of heart attack or stroke, they found a telling paradox: the fear was far greater than the actual risk.
The Oxford team, based at the Nuffield Department of Primary Care Health Sciences, has developed a new calculator that estimates an individual's risk of developing serious muscle disorders from statin use. Published in The Lancet Digital Health, the research draws on anonymized health records from more than 5.6 million people registered with GP practices across England—the largest dataset of its kind used to study this question. Of those, 1.7 million people informed the model's development, while another 3.9 million were used to test its accuracy.
The findings are striking: more than 98% of people identified by their GPs as eligible for statin treatment were predicted to be at low risk of serious muscle disorders over the next decade. Yet despite this reassuring picture, more than 60% of people eligible for statins were not taking them—some of them at considerable risk of heart attack or stroke.
The calculator uses 22 routinely recorded factors—including age, sex, ethnicity, body mass index, smoking status, existing health conditions, previous muscle problems, vitamin D levels, and current medications—to estimate a person's risk of serious muscle disorders at one, five, and ten years. The team envisions it being used alongside existing cardiovascular risk tools like QRISK, giving patients and clinicians a fuller picture of both benefits and potential harms.
"Serious muscle disorders are one of the most widely discussed concerns about statins, but our findings suggest that the risk is very low for the vast majority of people who may benefit from treatment," said Dr. Cai, the study's lead author. She emphasizes that the research focused specifically on serious muscle disorders requiring hospital admission or death, not the milder aches and pains many patients report. Those milder symptoms, she notes, are often not actually caused by statins and shouldn't prevent people from starting treatment.
Professor James Sheppard, a senior author of the study, says the tool addresses a longstanding gap in clinical conversations. "Treatment decisions are often based on estimates of a person's future cardiovascular risk, but much less information is available about their individual risk of adverse outcomes," he said. "This research helps address that gap by providing a way to estimate a person's risk of serious muscle disorders alongside their cardiovascular risk."
The calculator is now available through the Oxford University Innovation software store, offering clinicians and patients a concrete way to move beyond generalized fears and toward personalized, informed decisions about one of the world's most widely prescribed class of drugs.