TUESDAY, July 21, 2015 (HealthDay News) -- Despite smaller, prior studies suggesting that the diabetes drug Actos might raise users' risk of bladder cancer, a large new study finds no evidence for such an effect.
However, the study did find an association between the use of Actos (pioglitazone) and a rise in the risk of pancreatic cancer, although experts say it's too early to draw any conclusive link.
As explained by the researchers, certain prior studies had suggested an increased risk of bladder cancer with the use of Actos.
Investigating further, a team led by Dr. Assiamira Ferrara of Kaiser Permanente Northern California in Oakland looked at long-term data from nearly 200,000 diabetes patients.
They found no statistically significant association between taking Actos and increased risk of bladder cancer. However, a small increased risk could not be ruled out, the investigators said.
The also analyzed long-term data from another group of more than 236,000 diabetes patients and found that taking Actos was associated with about a 40 percent increased risk of pancreatic cancer.
However, further investigation is needed to learn more about this link, the researchers said.
One expert agreed, saying it's tough to conclude from this type of study that the use of Actos in any way helps cause pancreatic cancer.
Dr. Igor Astsaturov is an attending physician of medical oncology at Fox Chase Cancer Center in Philadelphia. He noted that inflammation is a key risk factor for pancreatic cancer, and chronic inflammation is common in people with diabetes.
"Most likely, the diabetes linkage to pancreatic cancer has a common denominator -- the presence of chronic inflammation in the pancreas," he explained.
Sicker people with more advanced cases of diabetes may also be more likely to be prescribed Actos, so the inflammation tied to diabetes may be the culprit -- not the pill, Astsaturov said.
The study, published in the July 21 issue of the Journal of the American Medical Association, was funded by drug maker Takeda, which makes Actos.
The American Cancer Society has more about bladder cancer.