Some studies indicate that, when implemented early in the course of type 2 diabetes mellitus, treatment with intensive insulin therapy for 2 to 3 weeks can induce a glycaemic remission resulting in patients being able to maintain normoglycaemia without drug therapy.
In The Lancet Diabetes & Endocrinology, researchers report a systematic review and meta-analysis of the effects of short-term intensive insulin therapy on β-cell function, insulin resistance, and remission of type 2 diabetes. They pooled data from seven studies (n=839), five studies of which were non-randomised.
Using the Homeostasis Model Assessment (HOMA), treatment with intensive insulin therapy for 2 to 3 weeks, implemented soon after diagnosis, improved β-cell function by 13% (hazard ratio; 1.13, 95% CI 1.02—1.25), and reduced insulin resistance by 43% (−0.57, −0.84 to −0.29). In the four studies that assessed glycaemic remission (n=559), those in drug-free remission was about 66•2% (292 of 441 patients) after 3 months of follow-up, about 58•9% (222 of 377) after 6 months, about 46•3% (229 of 495) after 12 months, and about 42•1% (53 of 126) after 24 months.
The authors of a accompanying Comment article suggest that these findings are due to removal of glucose toxicity which improves β-cell function and insulin resistance. They add that the findings relating to diabetes remission rates, may in part be due to a Hawthorne or observation effect, where participants knowing that they were under observation, are likely to have promoted the required changes in lifestyle needed in the treatment of type 2 diabetes- an effect which could be amplified by a short course of insulin, particularly if accompanied by hospital admission, as was done in three of the four studies reporting on remission. They noted that all but one of the studies in the meta-analysis, was conducted in China, which will affect the external validity of the findings, as type 2 diabetes in Asia and China has special features such as good responsiveness to acarbose and sulfonylureas, and low insulin dose requirements- and remission of type 2 diabetes after a short intensive insulin course could well be another of these features. In addition, as all studies were uncontrolled, further studies should include a control group with equal attention given to diet and exercise and pharmacological treatment given according to a well established guideline. At present, they suggest that based on these findings, it would not seem unreasonable to offer a Chinese patient diagnosed with type 2 diabetes, a short course of intensive insulin therapy with the aim of inducing remission. However, for other ethnic groups, short-term intensive insulin therapy warrants further investigation as a therapeutic strategy in early type 2 diabetes and there is no reason to deviate from current treatment guidelines.
Current NICE guidance on type 2 diabetes does not address the use of insulin in this setting.