Background: Previous studies have demonstrated cognitive impairment during severe hypoglycaemia. This study provides quantitative results on cognitive function during an acute mild hypoglycaemic episode in patients with type 2 diabetes.

Methods: In this double-blinded randomized cross-over study, 25 patients with type 2 diabetes attended two experimental visits with hyperinsulinaemic glucose clamping; one hypoglycaemic clamp (PG 3.0 ± 0.2 mmol/l) and one euglycaemic clamp (PG 6.0 ± 0.2 mmol/l). Cognitive function was assessed during each condition with a neurocognitive test battery measuring verbal memory, executive function, sustained attention and psychomotor speed.

Results: The participant’s cognitive performances were impaired during hypoglycaemia with mean score in the primary outcome test, SDMT, of 48.7 (hypoglycaemia) and 56.6 (euglycaemia); the estimated treatment difference was -7.9 (95% CI -10.9, -4.9; p=<0.0001). The composite score of overall speed of complex cognitive processing showed a highly significant deterioration during the hypoglycaemic condition of -0.7 (95% CI -0.9, -0.6; p=<0.0001) (Figure). Age, sex, fasting C-peptide and hypoglycaemic symptom severity did not influence the effect of hypoglycaemia on cognitive function.

Conclusion: Acute mild hypoglycaemia (3 mmol/l [54 mg/dl]) negatively affects cognitive function in patients with type 2 diabetes.


M. Nilsson: None. N.J. Jensen: None. M. Gejl: Other Relationship; Self; Novo Nordisk A/S. I. Brandslund: None. H. Storgaard: Advisory Panel; Self; Boehringer Ingelheim Pharmaceuticals, Inc. M. Zander: None. K. Miskowiak: None. J. Rungby: None.


Investigator Initiated Studies Program of Merck Sharp & Dohme Corp.

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