The agents achieve good blood sugar control for up to 15 years, making insulin injections unnecessary.
SAN FRANCISCO—Most patients with type 2 diabetes may be able to control their disease for up to 15 years and still avoid insulin injections by using multiple classes of oral diabetic medications.
The findings, which researchers presented here at the annual meeting of the Endocrine Society, contradict common beliefs about non-insulin diabetic medications.
“Generally, both patients and physicians believe that long-term use of oral diabetic mediations is not possible because these drugs lose their effectiveness over time as the patient’s pancreas fails,” said principal investigator Arthur Swislocki, MD, professor of medicine at the University of California at Davis and chief of the Endocrine Section at the Veterans Affairs (VA) Northern California Health Care System in Martinez.
“Our data suggest that some patients can remain in good glucose control for years using non-insulin, oral diabetic agents.”
Some patients prefer pills over insulin injections for various reasons, including ease of use, fear of needles, and the possibility of insulin-induced low blood glucose, he noted.
Dr. Swislocki and his colleagues studied the medical records of 191 veterans (188 men and three women) with type 2 diabetes who received treatment beginning in 1992 and were followed up for 15 consecutive years. Of these patients, 96 began treatment solely with oral drugs. Fifty-three (55%) of these patients were able to continue using them 15 years later and achieve good blood sugar control. In the 53 patients, the hemoglobin A1c improved from an average of nearly 8% to about 7% 15 years later, Dr. Swislocki and his team found.
Of the 96 patients, 45% eventually switched to insulin, either alone or in combination with oral drugs. At the beginning of the study, the duration of diabetes was similar between these patients and those who remained on oral drugs.
The group of patients who stayed on oral medications throughout the study had lower baseline A1c levels and were less obese than patient in the other group. In addition, patients who remained on oral agents were more likely to be Caucasian. Past studies have shown that minorities have worse blood sugar control than Caucasians.
The long-term effectiveness of oral agents observed in this study may reflect the wider range of oral drugs now available for treating type 2 diabetes compared with 15 years ago. Therefore, if one class of drugs became less effective, other classes could be added in combination. The study, however, did not specifically address whether oral drugs lose their effectiveness over a long time, Dr. Swislocki said. Rather, it mainly tracked the prescribing practices of VA primary-care providers.
“Deductions about drug effectiveness need to be made cautiously,” he said. “These findings should be of interest to nephrologists because the leading cause of renal failure in the United States is diabetes.”
Dr. Swislocki also observed: “The paradigm has changed, and after 10 or 15 years of diabetes most patients are on oral agents. However, even though we showed this in our small sample, it is important that they realize this study was mostly with men and it was done in only part of the country.”
According to 2007 data from the Centers for Disease Control and Prevention, diabetes affects 24 million Americans. The disease is present in about one fourth of the population aged 60 years and older. Native Americans and Alaska natives have the highest rate (16.5%).