Fasting hypoglycaemia secondary to carnitine deficiency: a late consequence of gastric bypass

Twelve years following gastric bypass surgery, a cachectic 69-year-old woman presented with both fasting and postprandial hypoglycaemia. Postprandial symptoms were relieved by dietary modification and acarbose, as is common in such cases. During a supervised fast, symptomatic hypoglycaemia occurred. Concurrent laboratory testing showed suppression of plasma insulin, c-peptide, proinsulin and insulin-like growth factor II. However, beta-hydroxybutyrate was also low, surprising given insulin deficiency. Elevated plasma free fatty acid (FFA) concentrations suggested that lipolysis was not impaired, making cachexia/malnutrition a less likely cause of hypoglycaemia. The apparent diagnosis was failure to counter-regulate—subsequent plasma carnitine measurements showed carnitine deficiency which presumably prevented FFA transport across mitochondrial membranes for ketogenesis. Repletion with high-dose oral carnitine supplements effected resolution of fasting hypoglycaemia.

Relationship between hypoglycaemia, cardiovascular outcomes, and empagliflozin treatment in the EMPA-REG OUTCOME® trial

Aims Hypoglycaemia, in patients with Type 2 diabetes (T2D) is associated with an increased risk for cardiovascular (CV) events. In EMPA-REG OUTCOME, the sodium-glucose co-transporter-2 inhibitor empagliflozin reduced the risk of CV death by 38% and heart failure hospitalization (HHF) by 35%, while decreasing glycated haemoglobin (HbA1c) without increasing hypoglycaemia. We investigated CV outcomes in patients with hypoglycaemia during the trial and the impact of hypoglycaemia on the treatment effect of empagliflozin. Methods and results About 7020 patients with T2D (HbA1c 7–10%) were treated with empagliflozin 10 or 25 mg, or placebo and followed for median 3.1 years. The relationship between on-trial hypoglycaemia and CV outcomes, and effects of empagliflozin on outcomes by incident hypoglycaemia [HYPO-broad: symptomatic hypoglycaemia with plasma glucose (PG) ≤70 mg/dL, any hypoglycaemia with PG <54 mg/dL, or severe hypoglycaemia, and HYPO-strict: hypoglycaemia with PG <54 mg/dL, or severe hypoglycaemia] was investigated using adjusted Cox regression models with time-varying covariates for hypoglycaemia and interaction with treatment. HYPO-broad occurred in 28% in each group and HYPO-strict in 19%. In the placebo group, hypoglycaemia was associated with an increased risk of HHF for both HYPO-broad [hazard ratio (HR, 95% confidence interval, CI) 1.91 (1.25–2.93)] and HYPO-strict [1.72 (1.06–2.78)]. HYPO-broad (but not HYPO-strict) was associated with an increased risk of myocardial infarction (MI) [HR 1.56 (1.06–2.29)]. Empagliflozin improved CV outcomes, regardless of occurrence of hypoglycaemia (P-for interactions >0.05). Conclusion In this post hoc exploratory analysis, hypoglycaemia was associated with an increased risk of HHF and MI. Hypoglycaemia risk was not increased with empagliflozin and incident hypoglycaemia did not attenuate its cardio-protective effects.

The Clinical use of glimepiride in patients with type 2 diabetes mellitus, uncontrolled on combination of DPP4-inhibitors and metformin: results of ESCALATION observational study

Background. Russian guidelines for T2DM management 2015 recommend intensification to triple combination therapy in patients not reaching glycaemia treatment targets on dual oral antidiabetic therapy for 6 months. Despite this, clinical experience shows that physicians may also switch one component of the dual therapy, or add the third component of the therapy. This study sought to assess the effect of physician-led prescription of glimepiride (GLIM) to individuals with T2DM uncontrolled by metformin (MET) and DPP-inhibitor. Material and methods. This observational study was carried out in real clinical practice in 142 Russian clinical centers, among 1447 T2DM patients, which consume glimepiride according to medical disposal. Entry criteria included 18—80 years male and female with HbA1c≥ 7,6% и ≤10 (during 2 month) and uncontrolled carbohydrate metabolism by individualized HbA1c target level by MET(in a dose ≥1500 mg/per day) and DPP-4i for ≥3 months, which doctor prescribed glimepiride in mono- or combination therapy. Duration of observation after inclusion into research was 24 weeks. Results. Patients were prescribed glimepiride as part of three-component therapy — GLIM+MET+DPP-4i (54.5%), two-component — GLIM+MET (34.4%), in other combinations — GLIM+other (11.1%). Mean HbA1c reduction at 24 weeks was 1.49±0.71%, and fasting blood glucose (FBG) reduction — 2.18±1.38 mmol/l. Significant changes in glycemic control in different groups of patients were not committed. Postprandial blood glucose (PPG, mmol/l) on an average decreased — 3.00±1.71, in groups GLIM+MET+DPP-4i, GLIM+MET and GLIM+other 2.98±1.63; 3.07±1.81 и 2.95±1.84. At week 24, body mass index (BMI, kg/m2 )was overall decrease by 0.36±1.99 and not significantly reduced in the GLIM+MET+DPP-4i, GLIM+MET and GLIM+other groups. Adverse events (AEs), inclusive of symptomatic hypoglycaemia, were reported in 370 patients (25.8% of all participants). In GLIM+MET+DPP-4i, GLIM+MET and GLIM+other groups frequency of symptomatic hypoglycaemia composed 13.2, 8.5 и 14.5%. Incidence of asymptomatic hypoglycaemia was reported at 8.4% of patient. In GLIM+MET+DPP-4i, GLIM+MET and GLIM+other groups it were 8.4, 7.3 и 11.9% , with maximum in GLIM+other group. There were no significant differences in the proportions of patients with hypoglycaemic episodes between other study groups. No episodes of severe hypoglycaemia or serious AEs were reported. Conclusion. More than a half of incidences of uncontrolled T2DM by metformin and DPP-4 inhibitor combination treatment in real-life clinical practice is intensify by prescribing three-component treatment setting. Approximately, in third cases the choice of the therapeutic approach depend on switch of iDPP-IV for the GLIM. Further 11.1% composed combinations glimepiride+ iDPP-IV (DRC). Various combinations of GLI with MET and/or iDPP4 provided improvement of glycemic control, affecting of HbA1c, FPG and PPG. During the study, there was no significant difference in glycemic control between different types of the therapy. Episodes of symptomatic hypoglycemia were more frequent in the DRC group compared with the group GLY+MET. No severe hypoglycemic events and no influence for body weight were reported in research indicating the safety of GLIM at T2DM patients uncontrolled by metformin and DPP-4 inhibitor combination therapy.

Severe paraneoplastic hypoglycemia secondary to a gastrointestinal stromal tumour masquerading as a stroke

Summary We report the case of a 70-year-old previously healthy female who presented acutely to the Accident and Emergency department with left-sided vasomotor symptoms including reduced muscle tone, weakness upon walking and slurred speech. Physical examination confirmed hemiparesis with VIIth nerve palsy and profound hepatomegaly. A random glucose was low at 1.7 mmol/l, which upon correction resolved her symptoms. In hindsight, the patient recalled having had similar episodes periodically over the past 3 months to which she did not give much attention. While hospitalized, she continued having episodes of symptomatic hypoglycaemia during most nights, requiring treatment with i.v. dextrose and/or glucagon. Blood tests including insulin and C-peptide were invariably suppressed, in correlation with low glucose. A Synacthen stimulation test was normal (Cort (0′) 390 nmol/l, Cort (30′) 773 nmol/l). A computed tomography scan showed multiple lobulated masses in the abdomen, liver and pelvis. An ultrasound guided biopsy of one of the pelvic masses was performed. Immunohistochemistry supported the diagnosis of a gastrointestinal stromal tumour (GIST) positive for CD34 and CD117. A diagnosis of a non islet cell tumour hypoglycaemia (NICTH) secondary to an IGF2 secreting GIST was confirmed with further biochemical investigations (IGF2=96.5 nmol/l; IGF2:IGF1 ratio 18.9, ULN <10). Treatment with growth hormone resolved the patient's hypoglycaemic symptoms and subsequent targeted therapy with Imatinib was successful in controlling disease progression over an 8-year observation period. Learning points NICTH can be a rare complication of GISTs that may manifest with severe hypoglycaemia and neuroglucopenic symptoms. NICTH can masquerade as other pathologies thus causing diagnostic confusion. Histological confirmation of GIST induced NICTH and exclusion of other conditions causing hypoglycaemia is essential. Mutational analysis of GISTs should be carried out in all cases as it guides treatment decision. Tailored management of hypoglycaemia, in this case using growth hormone and targeted cyto-reductive therapy, minimizes the risk of possible life-threatening complications.