Endocrine Abstracts

Background: Sleep loss is increasingly common in the western world and has been shown to be associated with an increased risk of diabetes mellitus and obesity.

Objective: We hypothesised that short term sleep loss results in a diabetogenic metabolic status during carbohydrate challenge at a breakfast buffet.

Subjects and methods: Fifteen healthy, normal-weight young men were studied in randomized balanced order on the subsequent morning after (i) two nights with 8 h sleep and (ii) after two nights with only 4 h sleep in the second half of the night. Blood glucose and relevant hormones (insulin, C-peptide, and glucagon) were measured after awakening and during a standardised breakfast buffet. The study was approved by the ethics committee of the University of Lübeck and all subjects gave written informed consent.

Results: Circulating morning concentrations of any parameter were comparable between conditions (P>0.30 for all comparisons). There was no difference in carbohydrate composition of ingested breakfast between conditions (P>0.35). In response to breakfast blood glucose (P<0.001) as well as serum insulin (P=0.02) and C-peptide concentrations (P=0.01) raised to distinctly higher concentrations in the 4 h than in the 8 h sleep condition. Also, plasma glucagon levels increased rapidly in response to breakfast with concentrations being constantly lower after 4 h than 8 h sleep (P=0.03).

Conclusion: Data indicate that short-term sleep loss markedly reduces glucose tolerance with the pattern of blood glucose and insulin response pointing to insulin resistance as the underlying mechanism. Thus results provide strong evidence for a causal link between sleep loss and the development of type 2 diabetes mellitus.