The British Medical Journal has published the results of a meta-analysis that aimed to assess the effect of intensive blood glucose lowering on cardiovascular outcomes and microvascular events in patients with type 2 diabetes.
The analysis included 13 studies involving 34,533 participants (18,315 in the intensive treatment group and 16,218 in the standard treatment group). The primary outcomes for the study were all cause mortality and cardiovascular death with secondary outcomes of severe hypoglycaemia, macrovascular and microvascular events. The studies all involved patients over the age of 18 years (mean age of 62 years) and with a diagnosis of type 2 diabetes. The mean follow up for the studies was 5 years.
There was no difference noted in the primary outcomes. In the secondary outcomes, intensive glucose lowering was associated with a reduced risk of non-fatal myocardial infarction and new onset microalbuminuria but an increased risk of severe hypoglycaemia.
The results of this analysis indicate that intensively lowering blood glucose in 600 patients for 5 years would:
- Prevent 4 or 5 non-fatal myocardial infarctions
- Present 4 to 20 cases of new onset microalbuminuria
- Cause 12 to 40 cases of severe hypoglycaemia
The authors conclude that, "the overall results of this meta-analysis show limited benefits of intensive glucose lowering treatment". They note that the risk:benefit ratio of intensive glucose lowering remains uncertain and that more randomised controlled trials are needed.
This study adds yet more weight to using an holistic approach to treat type 2 diabetes with due consideration of preventing macrovascular and microvascular complications. Lifestyle interventions, blood pressure and lipid management should be prioritised ahead of intensive glucose management.
Action: Clinicians should be aware of this analysis. Intensive glucose lowering should only be a consideration once all other interventions are effectively implemented.