Swiss researchers recently concluded that Avandia, a type 2 diabetes drug, nearly doubles the chances of osteoporosis and bone fracture among patients who take the drug and is increased for patients taking the drug for more than a year. The results of the study come on heels of controversy surrounding the drug's link to increased heart disease and various studies warning of potential risks related to bone degradation.
The type 2 diabetes drug was introduced to the market in 1999 from GlaxoSmithKline, and has been reportedly prescribed to nearly 3.5 million Americans suffering from the disease. Avandia was once considered one of the most popular treatments until results of several clinical trials reported in the news in 2007 determined a strong connection of the drug to cardiomyopathy and cardiovascular disease. One study, published by the Cleveland Clinic, found a 43 percent increase for patients developing these various heart diseases. Dr. John Buse, an expert on diabetes, has openly stated that Avandia may have been responsible for approximately 83,000 preventable myocardial infarctions over the last few years.
Additional studies then began to surface linking the drug to an increased risk of osteoporosis, although many of the studies did not have definitive proof of the connection until the recent Swiss study was published. The Swiss study determined patients on Avandia and Actos, which is also part of the Avandia class of drugs known as thiazolidinediones, doubled and, in some cases, tripled the odds of non-spine fractures among patients, according to news reports. For patients who took the drug for 12 to 18 months, this risk increased, and for those on the drug longer than two years were found to be at the highest risk of bone fracture and osteoporosis.
Osteoporosis is a disease characterized by loss of bone density and leads to abnormally porous bones, thus increasing the fragility of bones and an increase of fractures and breaks. A bone diseased with osteoporosis will have a density similar to that of a sponge, whereas healthy bones have a brick-consistent density level. Bones are made up of collagen, calcium and protein to ensure strength. Avandia was found to inhibit the development of osteoclasts and osteoblasts, which are cells that induce the redevelopment of healthy bone over time. It has been suggested that nearly 18 million Americans are at risk for osteoporosis and those taking Avandia increase that risk as well as the odds for early onset osteoporosis.
The Swiss researchers used medical records of over 1,000 diabetic patients who were diagnosed with bone fractures between the years of 1994 and 2005. The medical records included diagnosis of fractures for these patients from British physicians, and the research was compared to a control group of diabetics that did were not diagnosed with bone fractures during that time. Since these reports began to surface the manufacturer has seen a noticeable decline in sales. Most recently, the U.S. Food and Drug Administration (FDA) issued a warning letter to GlaxoSmithKline after a routine inspection turned up information being withheld by the company to the FDA on Avandia.
Although, the FDA has yet to address the new research on the osteoporosis and bone fracture risk of Avandia. In fact, the FDA has only responded to the controversial heart disease link by placing a black box warning on Avandia prescriptions, which some health experts consider to be a mild slap on the wrist considering the severe safety issues associated with the drug and many of these individuals are advocating removal of the drug from the market. The black box warning is the strongest label given by the FDA and warns of significant risk and the potential for life-threatening risks associated with taking a drug.
