A new study suggests that patients on the newer medications had a slightly lower risk of hospitalization because of diabetes-related complications. They also spent between $920 and $1,760 less on annual total healthcare costs.

The researchers analyzed more than three years’ worth of medical records’ data on patients who took thiazolidinediones (TZDs) or either metformin or a sulfonylurea to control their diabetes. TZDs (pioglitazone and rosiglitazone, brand names Actos and Avandia, respectively), were approved by the Food and Drug Administration in the late 1990s. Metformin and sulfonylureas have been on the market for more than 50 years.

“Taking a TZD as instructed was the strongest predictor of a reduced risk of hospitalization and decreased healthcare costs in this group of patients,” said Rajesh Balkrishnan, the study’s lead author and the Merrell Dow professor of pharmacy at Ohio State University Balkrishnan. The issue is that TZDs can be 10 times more expensive than the older diabetes drugs, Balkrishnan said. “

The researchers collected information on 3,191 adults enrolled in the North Carolina Medicaid program, which covers all medical and prescription costs of its enrollees. All of the participants had Type 2 diabetes and started medications for the disease between July 2001 and December 2003.

The enrollees were divided into two groups based on the type of drug their physicians prescribed: 1,774 took a TZD, while 1,417 took either metformin or a sulfonylurea. The researchers collected information on total healthcare expenditures and hospitalization rates for all patients through December 2004.

A brand-name TZD may cost $100 a month, while a prescription for a generic sulfonylurea or metformin may cost as little as $10 a month, Balkrishnan said.

The researchers compared how likely patients were to take their medications on time by collecting information on how often they refilled their prescriptions. The researchers assumed that a prescription filled meant that the previous prescription had been taken. Results showed that patients taking TZDs were more likely to refill their prescriptions on time.

Overall, the participants who took a TZD spent an average of $76 to $150 less per month on total healthcare costs, which adds up to about $920 to $1,760 less annually. The patients taking a TZD spent about $836.34 on monthly healthcare costs, compared to $983.13 per month for patients taking metformin and $913.11 per month for patients taking sulfonylureas.