Early intensive insulin therapy may be a better way of controlling newly diagnosed type 2 diabetes than oral hypoglycaemic agents, a Chinese study suggests.
In the multicentre, randomised, parallel-group trial supported by the Chinese government, the Natural Science Foundation of Guangdong Province government, leading insulin manufacturer Novo Nordisk (China) and Roche Diagnostics (Shanghai), 382 patients with fasting plasma glucose levels of 7.0-16.7 mmol/L were assigned to one of two insulin groups or to oral hypoglycaemic agents for initial rapid correction of hyperglycaemia.
The patients, aged 25-70 years, were enrolled from nine centres in China between September 2004 and October 2006. The two insulin groups were transient intensive insulin therapy (continuous subcutaneous insulin infusion/CSII) or multiple daily insulin injections (MDI). Treatment was halted after normal glucose levels (normoglycaemia) were maintained for two weeks. The patients were then followed up on diet and exercise alone.
The aim was to compare the effects of early intensive insulin and oral hypoglycaemics on beta-cell function and diabetes remission rates. Beta cells secrete insulin in the pancreas and their destruction or dysfunction is associated with the start of diabetes.
The researchers led by Professor Jianping Weng from the Third Affiliated Hospital of Sun Yat-Sen University in Guangzhou, China tested for intravenous glucose tolerance as well as measuring blood glucose, insulin and pro-insulin before and after therapy withdrawal and at one-year follow-up. The primary study endpoint was time of glycaemic remission and remission rate at one year after short-term intensive therapy.
Reporting the trial results in The Lancet, the researchers noted that more patients achieved target glycaemic control in the insulin groups – specifically, 97.1% or 133 of 137 on CSII and 95.2% or 118 of 124 on MDI – and in a shorter time (4.0 days on CSII, 5.6 days on MDI) than in the oral hypoglycaemic group (83.5% or 101 of 121 in 9.3 days). Remission rates after one year were significantly higher in the insulin groups (51.1% on CSII and 44.9% on MDI) than in the oral hypoglycaemic group (26.7%).
Beta-cell function as represented by HOMA (homeostasis model assessment ) B and acute insulin response improved significantly after intensive interventions. The increase in acute insulin response was sustained in the two insulin groups but declined significantly in the oral hypoglycaemic group at one year in all patients who had achieved glycaemic remission.
The results suggest that insulin injections may give beta cells in the pancreas a chance to recuperate and reverse some of the damage caused by high blood glucose levels, the authors commented.
Insulin therapy is still often prescribed as a last resort in diabetes, for a number of reasons including perceived fear of injections, the potential for weight gain or hypoglycaemia and the difficulty and inconvenience of learning and maintaining treatment regimens.
Pav Pank, care advisor at charity Diabetes UK, gave the Chinese study a qualified welcome, saying it “shows that considering using insulin early when people are first diagnosed with type 2 diabetes might be an additional way to achieve good diabetes management”.
Nevertheless, Pank added, decisions about treatment “need to be made on an individual basis for each patient. As using insulin introduces the risk of having hypos, good patient education on self-management is also crucial”.
