Doctors are being warned about placing their diabetes type 2 patients on intensive glucose lowering treatment, saying that it had no effect on all-cause or cardiovascular mortality. Reporting in the BMJ (British Medical Journal), they explained that doctors prescribe such treatment believing the patient will have reduced risk of heart complications.
The number of people with diabetes worldwide has increased considerably. In the year 2000 there were approximately 150 million affected people; this figure is expected to rise to 366 million within the next 20 years.
A patient with diabetes type 2 has over double the risk of developing a cardiovascular disease, compared to others – they also have a significantly higher chance of having damage to small blood vessels (microvascular complications).
Intensive glucose-lowering treatment, also known as glycemic lowering therapies, are commonly prescribed in order to reduce the diabetes type 2 patient’s risk of having cardiovascular complications, as well as renal and/or visual problems. However, the authors wrote that prior studies did not demonstrate compellingly whether the treatment provides real benefits.
Catherine Cornu, at the Louis Pradel Hospital in Bron, France, and team set out to examine whether there might be a link between the intensity of glycemic control and the risk of microvascular complications and cardiovascular events.
They gathered and analyzed data from 13 studies involving 34,533 individuals. 18,315 of them were prescribed intensive glucose lowering treatment, while 16,218 got standard treatment.
Intensive glucose treatment was found to have no significant effect on all-cause mortality or cardiovascular death.
The following benefits were identified with intensive glucose lowering treatments:
- The risk of non-fatal heart attacks dropped by 15%
- The risk of microalbuminuria fell by 10% (an indication of heart disease and kidney problems)
However, the treatment was associated with a 100% increase in the risk of dangerously low blood glucose levels (severe hypoglycemia).
Between 117 and 150 patients were estimated to have to need treatment to avoid one heart attack, 32 to 142 to avoid at least one case of microalbuminuria, and 15 to 20 to avoid a dangerous drop in blood sugar levels.
The authors concluded:
“Intensive glucose lowering treatment of type 2 diabetes should be considered with caution and therapeutic escalation should be limited.”
Kausik Ray, Professor of Cardiovascular Disease Prevention, Cardiac and Vascular Sciences, St George’s University of London, UK, wrote:
“Clinicians should consider these benefits and risks carefully because the most sensible treatment strategy will vary substantially between patients. Further studies are needed to determine whether an absolute HbA1c target should be established for everyone or whether HBA1c should be reduced by a target percentage from baseline, so that benefits and harms can be balanced.”
Rémy Boussageon, Theodora Bejan-Angoulvant, Mitra Saadatian-Elahi, Sandrine Lafont, Claire Bergeonneau, Behrouz Kassaï, Sylvie Erpeldinger, James M Wright, François Gueyffier, Catherine Cornu
BMJ 2011;343:d4169 doi: 10.1136/bmj.d4169
Written by Christian Nordqvist