Showing papers by "Bastiaan E. de Galan published in 2016"

Brain glucose metabolism during hypoglycemia in type 1 diabetes: insights from functional and metabolic neuroimaging studies.

Abstract: Hypoglycemia is the most frequent complication of insulin therapy in patients with type 1 diabetes. Since the brain is reliant on circulating glucose as its main source of energy, hypoglycemia poses a threat for normal brain function. Paradoxically, although hypoglycemia commonly induces immediate decline in cognitive function, long-lasting changes in brain structure and cognitive function are uncommon in patients with type 1 diabetes. In fact, recurrent hypoglycemia initiates a process of habituation that suppresses hormonal responses to and impairs awareness of subsequent hypoglycemia, which has been attributed to adaptations in the brain. These observations sparked great scientific interest into the brain's handling of glucose during (recurrent) hypoglycemia. Various neuroimaging techniques have been employed to study brain (glucose) metabolism, including PET, fMRI, MRS and ASL. This review discusses what is currently known about cerebral metabolism during hypoglycemia, and how findings obtained by functional and metabolic neuroimaging techniques contributed to this knowledge.

Brain Lactate Concentration Falls in Response to Hypoglycemia in Patients With Type 1 Diabetes and Impaired Awareness of Hypoglycemia.

Abstract: Brain lactate may be involved in the development of impaired awareness of hypoglycemia (IAH), a condition that affects approximately 25% of patients with type 1 diabetes and increases the risk of severe hypoglycemia. The aim of this study was to investigate the effect of acute hypoglycemia on brain lactate concentration in patients with IAH as compared with those with normal awareness of hypoglycemia (NAH) and healthy control subjects (n = 7 per group). After an overnight fast, all subjects underwent a two-step hyperinsulinemic euglycemic (5.0 mmol/L)-hypoglycemic (2.8 mmol/L) glucose clamp. Brain lactate concentrations were measured continuously with (1)H-MRS using a specific lactate detection method. Hypoglycemia generated symptoms in patients with NAH and healthy control subjects but not in patients with IAH. Brain lactate fell significantly by ∼20% in response to hypoglycemia in patients with type 1 diabetes with IAH but remained stable in both healthy control subjects and in patients with NAH. The fall in brain lactate is compatible with increased brain lactate oxidation providing an alternative fuel source during hypoglycemia, which may contribute to the impaired detection of hypoglycemia.

Insulin glargine 300 U/mL in the management of diabetes: clinical utility and patient perspectives.

Abstract: There is ongoing interest in optimizing basal insulin treatment by developing insulins with a flat pharmacological profile, a long duration of action (typically beyond 24 hours) and minimum day-to-day variation. Glargine-300 is a modified form of the long-acting insulin analog glargine in that it has been concentrated at 300 units/mL rather than the conventional 100 units/mL. Glargine-300 has a longer duration of action and a flatter pharmacological profile than original glargine-100. This property allows for more flexibility around the timing of administration, when injected once per day. Open-label studies in patients with diabetes have shown that treatment with glargine-300 achieves comparable glycemic control compared to treatment with glargine-100, albeit with consistently higher insulin requirements. These studies also showed that treatment with glargine-300 was associated with lower risks of nocturnal hypoglycemia in patients with type 2 diabetes, particularly those already on insulin, whereas data are mixed in insulin-naive patients with type 2 diabetes or in patients with type 1 diabetes. Treatment with glargine-300 did not appear to affect the risk of overall hypoglycemia, whereas studies lacked sufficient power to investigate the effect on the risk of severe hypoglycemia. Future studies need to establish the role of glargine-300 in the treatment of diabetes alongside the other new long-acting insulin analog, insulin degludec, which was recently introduced to the market.