Two popular drugs used to treat late-onset diabetes may double the risk of heart failure, according to a new study.
Researchers who analysed data on 78,000 patients who took Avandia or Actos to treat type II diabetes found that it increased the risk of heart failure by up to 100 percent, said the study released today.
The researchers estimate that for every 50 patients taking the medications over a period of 26 months, one person will develop heart failure.
The manufacturers cautioned from the beginning that the drugs were not suitable for patients at risk for - or with a history of -- heart failure, and that patients who combined the drugs with insulin treatments were at increased risk for this complication.
However, this analysis found that this adverse effect occurred in patients with no risk for heart failure, even in the absence of insulin. The study also showed that it occurred in young people and at high and low doses.
On average, patients who developed this complication did so 24 weeks after starting on the drug, the investigators report in the journal Diabetes Care.
GlaxoSmithKline, which has been marketing Avandia in the United States since 1999 and in Europe since 2000, downplayed the findings. Actos is made by Takeda Pharmaceutical.
'The risk of heart failure in diabetes patients and with use of these medicines is well recognized and is clearly identified in prescribing information to doctors,' the company said in a statement.
'GSK is confident in the overall safety profile of rosiglitazone (trade name for Avandia) when used appropriately', it added.
GSH's blockbuster drug has also been linked with other problems. In May, a study in a US medical journal said people taking the drug had a 43% higher risk of heart attack.
The US Food and Drug Administration will consult with medical experts on Monday to see whether the new data merits adding so-called 'black box' warnings to the drug packaging that would alert consumers to the potential risk.
