Insulin Restriction in Women With Type 1 Diabetes May Increase Mortality

Insulin restriction in women with type 1 diabetes was associated with increased morbidity and mortality, according to the results of a new study. 

A new study suggests that women with type 1 diabetes who take less insulin than prescribed had a 3-fold increased risk of death and higher rates of disease complications compared with those who did not skip needed insulin shots

The objective of this 11-year follow-up study was to determine whether insulin restriction in women with type 1 diabetes predicted higher rates of diabetic complications and an increased risk for mortality more than 10 years later.

Of the original study sample, 234 women (60% of the original cohort) took part in the follow-up evaluation. At follow-up, mean age was 45 years, mean duration of diabetes was 28 years, mean body mass index (BMI) was 25 kg/m2, and mean hemoglobin A1c (HbA1c) level was 7.9%. Baseline measures evaluated diabetes self-care behaviors, diabetes-specific distress, fear of hypoglycemia, psychologic distress, and eating disorder symptoms. Mortality data were gleaned from state and national databases, and follow-up data concerning diabetic complications were obtained by self-report.

At baseline, 71 (30%) women reported insulin restriction. During follow-up, 26 women had died. After controlling for baseline age, BMI, and HbA1c levels, insulin restriction was associated with a 3-fold increased risk for mortality, according to the results of multivariate Cox regression analysis.

Compared with women who did not restrict insulin, those who did had died at a younger age (mean, 45 vs 58 years; P < .01) and had higher reported rates of nephropathy and foot problems at follow-up. Compared with survivors, women who died during follow-up had reported more frequent insulin restriction (P < .05) and more symptoms of eating disorders (P < .05) at baseline.

"Our data demonstrate that insulin restriction is associated with increased rates of diabetes complications and increased mortality risk," the study authors write. "Mortality associated with insulin restriction appeared to occur in the context of eating disorder symptoms, rather than other psychological distress."

Practice Pearls:

• Insulin restriction in women with type 1 diabetes is associated with 3 times higher mortality than women who use appropriate insulin at 11 years of follow-up.
• Insulin restriction in women with type 1 diabetes is associated with higher rates of self-reported nephropathy and foot problems.

Source: Diabetes In Control: Diabetes Care. 2008;31:1-5.