Diabetes drugs 'double risk of heart failure'
Friday, 27 July 2007
Print
Email
Up to 10,000 patients in Britain may be at risk of heart failure because they take drugs for diabetes.
UK and US researchers have found two of the world's top selling oral medications for diabetes double the risk of heart failure.
The discovery in a study published yesterday is a major blow for sufferers from type 2 diabetes - there at least two million in the UK. The drugs, known as glitazones, are Avandia, made by GlaxoSmithKline, and Actos, made by Takeda. They sensitise the body to insulin and lower blood sugar levels and were hailed as a major advance against the disease when they were launched.
But researchers who analysed existing studies and case reports covering more than 78,000 patients, estimated that one in every 50 patients treated with the drugs over 26 months would suffer heart failure as a result.
An estimated 500,000 patients in the UK are taking the drugs, according to Glaxo SmithKline, implying that 10,000 patients could be at risk.
The study, published in Diabetes Care, follows a report in May linking Avandia with a 43 per cent increased risk of a heart attack. That study, published in the New England Journal of Medicine, led to a collapse in prescriptions for Avandia.
Two advisory panels for the US Food and Drug Administration are re-examining both drugs. Experts expect the FDA to rule that a "black box" warning be displayed on the packaging to alert doctors and patients to the risks.
The European Medicines Agency said it was reviewing both drugs and would publish its findings later in the year. They are approved for use on the NHS by the National Institute for Clinical Excellence.
The drugs are not recommended for people suffering from, or at risk of, heart failure. But the new study, carried out by experts at the University of East Anglia (UEA) and Wake Forest University in North Carolina, suggests an increased risk even for those who have never suffered heart failure.
Yoon Loke, a clinical pharmacologist at UEA, who led the study said the findings meant the drugs "could have caused thousands of additional cases of heart failure, creating a substantial burden on hard-pressed NHS services".
He added: "Most patients did not have heart failure prior to starting on treatment with these drugs. There doesn't seem to be a group of patients who are safe from these side effects. I think Nice should re-evaluate its decision to recommend these drugs."
One of the causes leading to heart failure was too much fluid on the lungs. "We think this is one of the main mechanisms in this case," he said.
GlaxoSmithKline said the risk of heart failure with the medicines was "well recognised and clearly identified in prescribing information to doctors in the UK." It added it was well known that glitazones could cause fluid retention that could lead to heart failure and was "clearly stated".
