Insulin: Potential Negative Consequences of Early Routine Use in Patients With Type 2 Diabetes
Some extracts from the full paper.
It would seem logical that the ideal treatment for type 2 diabetes should be early and continuing insulin therapy. Unfortunately, there are several characteristics of insulin treatment and insulin action in type 2 diabetes that limit the usefulness of insulin treatment and that suggest that chronic insulin therapy is best used in the later stages of diabetes when there is an absolute deficiency of insulin.
Starting insulin therapy early in the course of chronic treatment of patients with type 2 diabetes would imply that there are unique benefits to insulin treatment. As addressed above, there is little evidence to support such a view. Insulin treatment is neither durable in maintaining glycemic control nor is unique in preserving β-cells. Better clinical outcomes than those that occur with other antihyperglycemic regimens have not been shown. The downside of insulin therapy is the need to increase the dose and the regimen complexity with time, the increase in severe hypoglycemia, and the potential increase in mortality as well as the potential increased risk for specific cancers.
Weight gain accompanies insulin treatment. The magnitude of the weight gain is influenced by the level of the initial glycemic control, the treatment glycemic control achieved, the duration of insulin therapy, the insulin regimen used, and which combination of oral agents are concomitantly used For example, in a study normalizing the HbA1c during 6 months of intensive multiple-dose insulin therapy, the mean weight gain was 8.7 kg
For the vast majority of patients with type 2 diabetes, insulin therapy is best reserved until other therapies can no longer maintain the target glycemic goals.
Those on Metformin therapy had the lowest death rates, so that group was used as the reference.
In terms of primary outcome—that is, consideration of first adverse events only:
Sulfonylurea therapy resulted in patients being 1.4 times more likely to suffer one of these outcomes.
A combination of Metformin and Insulin resulted in 1.3 times greater risk.
Insulin therapy alone resulted in 1.8 times greater risk.
Those considered to be at greater risk because of glycosylated hemoglobin had as much as 2.2 times greater risk with Insulin therapy alone. When considering any of these events happening, whether they were the first event or a subsequent one, the results were even more dramatic:
Insulin monotherapy resulted in:
2.0 times more myocardial infarctions.
1.7 time more major adverse cardiac events
1.4 time more strokes
3.5 times more renal complications
2.1 time more neuropathy
1.2 times more eye complications
1.4 times more cancer
2.2 times more deaths
Full paper here
http://care.diabetesjournals.org/content/34/Supplement_2/S225.full