Risk of malignancies in patients with diabetes treated with human insulin or insulin analogues: a cohort study

Abstract

Aims/hypothesis The aim of this cohort study was to investigate the risk of malignant neoplasms and mortality in patients with diabetes treated either with human insulin or with one of three insulin analogues. Methods Data were provided by the largest German statutory health insurance fund (time-frame:

Does diabetes therapy influence the risk of cancer?

“…It will also be noted that the four insulin-treated groups were less evidently heterogeneous than patients in the other analyses we have considered. Numbers were, however, relatively small, with 2,286 on insulin glargine alone, compared with 1,262 on NPH insulin, and once again a dosage-based comparison, as performed in the German study [23], did not prove feasible.…”

“…Cancers take many years to develop, and it is therefore surprising that studies such as those reported in this issue of Diabetologia [10,[23][24][25] can claim to detect differences in cancer rates within a few years of exposure to different therapeutic agents. These observations, if confirmed, strongly suggest that the effects we are witnessing arise from differences in the rate of development of pre-existing malignant foci rather than malignant transformation and new cancer cell formation.…”

“…A large observational study submitted to this journal last year suggested that use of insulin glargine is, after adjustment for dose, associated with a possible increase in tumour risk in humans [23]. Interpretation of this analysis proved controversial, but the implications were serious.…”

“…German insurance study In this report [23], which triggered the remainder, Hemkens and colleagues present data from a large insurance dataset, and compare the rate of diagnosis of malignant tumours in patients treated with human insulin, as against three of its analogues: insulin lispro, insulin aspart and insulin glargine. Insulin detemir, more recently introduced to the German market, was not included.…”

“…Classification of diabetes was based on age at diagnosis, and those diagnosed after 30 years of age, including almost all those on insulin glargine alone, were considered to have type 2 diabetes. Insulin dose could only be estimated in terms of the number of insulin prescriptions filled, which meant that a dose-response relationship could not be examined in the same way as in the German study [23], which was based on recorded insulin doses. The endpoints were diagnosis of any neoplasm, and a diagnosis of a cancer of the breast, prostate or gastrointestinal tract.…”