Focusing on Blood Sugar Narrows Options for Diabetes, Says Study

30 Aug 2016 --- A new study has revealed that by focusing on lowering blood sugar in Type 2 diabetes, the medical community may have short-circuited development of new diabetes therapies.

The study, published by Mayo Clinic researchers in the journal Circulation, Cardiovascular Quality and Outcomes, systematically examined journal articles and clinical practice diabetes guidelines published in the last decade (2006 and 2015) for statements related to value of tight glycemic control in the prevention of chronic diabetic complications. 

The authors then compared them with the body of evidence accrued in the past two decades regarding the effect of tight glycemic control on patient-important micro- and macrovascular outcomes.

Researchers found that tight glycemic control, the maintenance of a hemoglobin A1c value lower than 7 percent, had no statistically significant impact on patient-important microvascular outcomes. In contrast, all practice guidelines and a majority of published statements, around 80 percent, support tight glycemic control to prevent those complications.

For patient-important macrovascular (cardiovascular) complications, the evidence shows that tight glycemic control reduces the risk of nonfatal heart attack by around 15 percent, but has no impact in all-cause mortality and cardiovascular mortality.

Furthermore, the risk of stroke did not seem to be lowered by tight glycemic control and the effect on amputation was imprecise.

In fact, during the studied time period, statements about tight glycemic control to prevent these complications shifted from largely supportive, around 85 percent, to skeptical, 20-30 percent, after the publication of a trial that was not consistent with the results of other studies, the Action to Control Cardiovascular Risk study in Diabetes trial in 2008.

Authors, Drs. Rodriguez-Gutierrez and Montori, suggest that the widespread consensus for tight glycemic control should be re-examined. They suggest glycemic moderation may help advance the individualization of diabetes care, using shared decision making to select glycemic targets and treatments. 

They hope that their new paper will spur research into new therapeutic approaches to prevent diabetes complications, saying, "Consider the list of evidence-based therapies recommended: to prevent retinopathy or neuropathy beyond glycemic control: none." 

The authors added that patients with Type 2 diabetes seem to live longer and with fewer complications, at least in some parts of the world. They suggest a careful and thoughtful recalibration of treatment could promote patient trust and provide new answers to this pandemic problem.