Intensive glucose control benefits patients with type 2 diabetes by reducing microvascular complications, a meta-analysis has shown.
The study, which included more than 27,000 patients across four clinical trials, found that more intensive glucose control resulted in a modest improvement in HbA1c compared to less intensive glucose control (6.80 v 7.74%).
However, over an average five-year follow-up there was a 20% reduction in risk of kidney complications according to a composite score including end-stage kidney disease, renal death or overt diabetic nephropathy.
Intensive glucose control also led to a 13% reduction in eye events as measured by a requirement for retinal photocoagulation therapy or vitrectomy, proliferative retinopathy, vitreous haemorrhage or progression of diabetic retinopathy.
Intensive glucose control also reduced the risk of the secondary eye outcome of need for cataract extraction.
Co-author Professor Sophia Zoungas, from Monash University, told the limbic the meta-analysis was not designed to draw conclusions on the specific agents used to achieve tighter glucose control.
However, it showed what could be achieved by titrating therapy to achieve a lower HbA1C target.
“An almost 1% difference in HbA1c is a big difference in this context. Considering the millions of people affected by type 2 diabetes, more intensive glucose control can clearly have a huge impact on the burden of complications,” she said.
The meta-analysis found the number of people that need to be treated to prevent one microvascular complication was about 73 for kidney events or 63 for eye events.
The study did not find any significant benefit in a composite measure of neuropathy including new loss of vibratory sensation, ankle reflexes or light touch.
However Professor Zoungas said a more standardised approach to measuring nerve outcomes in the original trials may have provided different results.
“To rigorously document nerve outcomes we would need to conduct more costly and time consuming nerve conduction studies,” she said.
An accompanying editorial in The Lancet highlighted the need to balance intensive glucose control with the increased risk of severe hypoglycaemic events.
Professor Zoungas said the increased risk of severe hypoglycaemia (hazard ratio 2.48) was documented in an earlier publication looking at macrovascular outcomes associated with intensive glucose control.
She added the research team was also looking ahead to document any likely ‘legacy effect’ on microvascular outcomes in the post-trial period.