Prevalence of insulin self manipulation in young women with insulin dependent diabetes

1. To determine the prevalence of insulin self manipulation for the purposes of weight control, in a population based study of young women with insulin dependent diabetes. 2. To compare the North Canterbury prevalence of insulin self manipulation with figures reported in overseas studies.

All women with insulin dependent diabetes aged 18 to 30 years inclusive and resident in North Canterbury, were invited to an interview to document their diabetes self-care behaviour. A blood sample was taken at the time of interview for measurement of glycated haemoglobin.

Ninety three percent of eligible women agreed to participate in the study. Twelve of the 69 participating women (17%) admitted to reducing their insulin dose at some time in the past, for the purposes of weight loss. This figure is significantly lower than the 37% (p = 0.047), reported from a British study, and the figure of 39% (p = 0.006), reported from the United States. The median glycated haemoglobin of the twelve subjects who reported manipulating their insulin was slightly higher than that of the remaining 57 subjects, but this difference did not reach statistical significance (79 mmol/mol haem versus 71 mmol/mol haem, p = 0.07).

The self reported prevalence of insulin manipulation for the purposes of weight loss appears to be lower in North Canterbury, compared to overseas studies. The reason for this difference is unexplained. Health care professionals should nevertheless be aware of this method of weight reduction, as it has been associated with poor diabetes control, clinical eating disorders and possible long term detrimental effects on health.