Researchers in Taipei, Taiwan, report that they have identified the top three drugs for reducing A1C levels in type 2 diabetes: biphasic insulin, GLP-1 analogs, and basal insulin. They hedged a little on their endorsement of GLP-1 analogs, however, by saying that although they are not decisively better at controlling A1Cs than other oral diabetes drugs, they have the advantage of helping to reduce weight without adding to the danger of hypoglycemia.
Biphasic insulin is a combination of intermediate- and fast-acting insulin. Basal insulin is the standard dose a person with diabetes takes daily, often supplemented by shorter-term bolus insulin to cover blood sugar spikes at meals. GLP-1 (glucagon-like peptide 1) analogs, which include exenatide and liraglutide, are derived from a gut hormone that helps increase insulin production and sensitivity and reduce glucagon production in the pancreas. A beneficial side effect is weight reduction.
The scientists at the Mackay Memorial Hospital, Division of Endocrinology and Metabolism, Department of Internal Medicine, Taipei, Taiwan, reached their conclusion after conducting a meta-analysis of drugs used to treat type 2 diabetes that was inadequately controlled by metformin. The analysis eventually studied 819 articles on diabetes drugs, including coverage of 39 controlled trials that involved almost 18,000 patients.
Overall, GLP-1 analogs were found to lead to a greater decrease in A1C levels than sulfonylureas, glinides, thiazolidinediones, alpha-glucosidase inhibitors, and DPP-4 inhibitors, producing results similar to those of basal and biphasic insulin.
According to the Taiwanese researchers, the meta-analysis also showed that compared with placebo, sulfonylureas, glinides, basal insulin, and biphasic insulin carried an increased risk of hypoglycemia.
While the study conclusions are interesting, the researchers cautioned that of the studies they reviewed, the longest was only 52 weeks-not long enough to establish a definitive long-term trend.