(HealthDay News) — Thiazolidinediones are associated with a lower risk of liver and colorectal cancer in patients with type 2 diabetes, according to a study published in the May issue of Hepatology.
Chia-Hsuin Chang, M.D., from the National Taiwan University Hospital in Taipei, and colleagues examined the risk of cancer in 606,583 adult patients with type 2 diabetes without a history of cancer treated with thiazolidinediones. After a median of 7.9 years, there were 10,741 cases of liver cancer, 7,200 cases of colorectal cancer, 5,361 cases of lung cancer, and 1,583 cases of bladder cancer, with 70,559 controls with diabetes.
The researchers found a significantly lower risk of liver in cancer in patients taking rosiglitazone (odds ratio [OR], 0.73) or pioglitazone (OR, 0.83), with stronger protection for higher cumulative dosages and longer duration. The risk of colorectal cancer was significantly lower only for rosiglitazone (OR, 0.86). There was no association between thiazolidinedione use and lung and bladder cancer, although there was a potentially higher risk of bladder cancer in patients taking pioglitazone for three years or more (OR, 1.56; 95 percent confidence interval, 0.51 to 4.74).
“The use of pioglitazone and rosiglitazone is associated with a decreased liver cancer incidence in diabetic patients,” Chang and colleagues conclude. “The effects on occurrence of specific cancer types may be different for pioglitazone and rosiglitazone.”