β-Cell Function, Incretin Effect, and Glucose Kinetics in Response to a Mixed Meal in Patients With Type 2 Diabetes Treated With Dapagliflozin Plus Saxagliptin

OBJECTIVE

To explore the complementary effects of a combination of dipeptidyl peptidase 4 and sodium-glucose cotransporter 2 inhibitors added to metformin on hormonal and metabolic responses to meal ingestion.

RESEARCH DESIGN AND METHODS

Forty-five patients (age 58 ± 8 years; HbA1c 58 ± 6 mmol/mol; BMI 30.7 ± 3.2 kg/m2) with type 2 diabetes uncontrolled with metformin were evaluated at baseline and 3 and 28 days after 5 mg saxagliptin (SAXA), 10 mg dapagliflozin (DAPA), or 5 mg saxagliptin plus 10 mg dapagliflozin (SAXA+DAPA) using a mixed-meal tolerance test (MMTT) spiked with dual-tracer glucose to assess glucose metabolism, insulin secretion, and sensitivity.

RESULTS

At day 3, fasting and mean MMTT glucose levels were lower with SAXA+DAPA (-31.1 ± 1.6 and -91.5 ± 12.4 mg/dL) than with SAXA (-7.1 ± 2.1 and -53 ± 10.5 mg/dL) or DAPA (-17.0 ± 1.1 and -42.6 ± 10.0 mg/dL, respectively; P < 0.001). Insulin secretion rate (SAXA+DAPA +75%; SAXA +11%; DAPA 3%) and insulin sensitivity (+2.2 ± 1.7, +0.4 ± 0.7, and +0.4 ± 0.4 mg ⋅ kg-1⋅ min-1, respectively) improved with SAXA+DAPA (P < 0.007). Mean glucagon-like peptide 1 (GLP-1) was higher with SAXA+DAPA than with SAXA or DAPA. Fasting glucagon increased with DAPA and SAXA+DAPA but not with SAXA. Fasting endogenous glucose production (EGP) increased with SAXA+DAPA and DAPA. During MMTT, EGP suppression was greater (48%) with SAXA+DAPA (vs. SAXA 44%; P = 0.02 or DAPA 34%; P = 0.2). Metabolic clearance rate of glucose (MCRglu) increased more with SAXA+DAPA. At week 4, insulin secretion rate, β-cell glucose sensitivity, and insulin sensitivity had further increased in the SAXA+DAPA group (P = 0.02), with no additional changes in GLP-1, glucagon, fasting or MMTT EGP, or MCRglu.

CONCLUSIONS

SAXA+DAPA provided superior glycemic control compared with DAPA or SAXA, with improved β-cell function, insulin sensitivity, GLP-1 availability, and glucose clearance.

The current landscape for diabetes treatment: Preventing diabetes-associated CV risk

Despite the risk of atherosclerosis has progressively declined over the past few decades, subjects with type 2 diabetes mellitus (T2DM) continue to experience substantial excess of atherosclerotic cardiovascular disease (ASCVD)-related events. Therefore, there is urgent need to treat ASCVD disease in T2DM earlier, more intensively, and with greater precision. Many factors concur to increase the risk of atherosclerosis, and multifactorial intervention remains the basis for effective prevention or reduction of atherosclerotic events. The role of anti-hyperglycemic medications in reducing the risk of ASCVD in subjects with T2DM has evolved over the past few years. Multiple cardiovascular outcome trials (CVOTs) with new and emerging glucose-lowering agents, namely SGLT2 inhibitors (SGLT2i) and GLP-1 receptor agonists (GLP1-RA), have demonstrated significant reductions of major cardiovascular events and additional benefits. This robust evidence has changed the landscape for managing people with T2DM. In addition to glycemic and ancillary extra-glycemic properties, SGLT2i and GLP1-RA might exert favorable effects on subclinical and clinical atherosclerosis. Therefore, the objective of this review is to discuss the available evidence supporting anti-atherosclerotic properties of SGLT2i and GLP1-RA, with a quick nod to sotagliflozin and tirzepatide.

Near-Infrared Spectroscopy: A Free-Living Neuroscience Tool to Better Understand Diabetes and Obesity

The human brain is the least accessible of all organs and attempts to study it in vivo rely predominantly on neuroimaging. Functional near-infrared spectroscopy (fNIRS) allows for the study of cortical neural activity in a non-invasive manner that may resemble free-living conditions. Moreover, compared to other neuroimaging tools, fNIRS is less expensive, it does not require the use of ionizing radiation, and can be applied to all study populations (patients suffering from claustrophobia, or neonates). In this narrative review, we provide an overview of the available research performed using fNIRS in patients with diabetes and obesity. The few studies conducted to date have presented controversial results regarding patients with diabetes, some reporting a greater hemodynamic response and others reporting a reduced hemodynamic response compared to the controls, with an unclear distinction between types 1 and 2. Subjects with obesity or a binge eating disorder have reduced prefrontal activation in response to inhibitory food or non-food stimuli; however, following an intervention, such as cognitive treatment, prefrontal activation is restored. Moreover, we discuss the potential of future applications of fNIRS for a better understanding of cortical neural activity in the context of metabolic disorders.

Effect of fasting on short-term visual plasticity in adult humans

Brain plasticity and function is impaired in conditions of metabolic dysregulation, such as obesity. Less is known on whether brain function is also affected by transient and physiological metabolic changes, such as the alternation between fasting and fed state. Here we asked whether these changes affect the transient shift of ocular dominance that follows short-term monocular deprivation, a form of homeostatic plasticity. We further asked whether variations in three of the main metabolic and hormonal pathways affected in obesity (glucose metabolism, leptin signalling and fatty acid metabolism) correlate with plasticity changes. We measured the effects of 2 h monocular deprivation in three conditions: post-absorptive state (fasting), after ingestion of a standardised meal and during infusion of glucagon-like peptide-1 (GLP-1), an incretin physiologically released upon meal ingestion that plays a key role in glucose metabolism. We found that short-term plasticity was less manifest in fasting than in fed state, whereas GLP-1 infusion did not elicit reliable changes compared to fasting. Although we confirmed a positive association between plasticity and supraphysiological GLP-1 levels, achieved by GLP-1 infusion, we found that none of the parameters linked to glucose metabolism could predict the plasticity reduction in the fasting versus fed state. Instead, this was selectively associated with the increase in plasma beta-hydroxybutyrate (B-OH) levels during fasting, which suggests a link between neural function and energy substrates alternative to glucose. These results reveal a previously unexplored link between homeostatic brain plasticity and the physiological changes associated with the daily fast-fed cycle.

Effect of empagliflozin on left ventricular contractility and peak oxygen uptake in subjects with type 2 diabetes without heart disease: results of the EMPA-HEART trial

Background

The mechanism through which sodium-glucose cotransporter 2 inhibitors (SGLT2i) prevent the incidence of heart failure and/or affect cardiac structure and function remains unclear.

Methods

The EMPA-HEART trial is aimed at verifying whether empagliflozin improves myocardial contractility (left ventricle global longitudinal strain, LV-GLS) and/or cardiopulmonary fitness (peak oxygen uptake, VO2peak) in subjects with type 2 diabetes (T2D) without heart disease. Patients with T2D, normal LV systolic function (2D-Echo EF > 50%), and no heart disease were randomized to either empagliflozin 10 mg or sitagliptin 100 mg for 6 months and underwent repeated cardiopulmonary exercise tests with echocardiography and determination of plasma biomarkers.

Results

Forty-four patients completed the study, 22 per arm. Despite comparable glycaemic control, modest reductions in body weight (− 1.6; [− 2.7/− 0.5] kg, p = 0.03) and plasma uric acid (− 1.5; [− 2.3/− 0.6], p = 0.002), as well as an increase in haemoglobin (+ 0.7; [+ 0.2/+ 1.1] g/dL, p = 0.0003) were evident with empagliflozin. No difference was detectable in either LV-GLS at 1 month (empagliflozin vs sitagliptin: + 0.44; [− 0.10/+ 0.98]%, p = 0.11) and 6 months of therapy (+ 0.53; [− 0.56/+ 1.62]%), or in VO_2peak (+ 0.43; [− 1.4/+ 2.3] mL/min/kg, p = 0.65). With empagliflozin, the subgroup with baseline LV-GLS below the median experienced a greater increase (time*drug p < 0.05) in LV-GLS at 1 month (+ 1.22; [+ 0.31/+ 2.13]%) and 6 months (+ 2.05; [+ 1.14/+ 2.96]%), while sitagliptin induced a modest improvement in LV-GLS only at 6 months (+ 0.92; [+ 0.21/+ 0.62]%).

Conclusions

Empagliflozin has neutral impact on both LV-GLS and exercise tolerance in subjects with T2D and normal left ventricular function. However, in patients with subclinical dysfunction (LV-GLS < 16.5%) it produces a rapid and sustained amelioration of LV contractility.

Trial registration EUDRACT Code 2016-002225-10

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01618-1.

Circulating microRNAs as clinically useful biomarkers for Type 2 Diabetes Mellitus: miRNomics from bench to bedside

Type 2 diabetes (T2D), a chronic metabolic disease, has attained the status of a global epidemic with steadily increasing incidence worldwide. Improved diagnosis, stratification and prognosis of T2D patients and the development of more effective treatments are needed. In this era of personalized medicine, the discovery and evaluation of innovative circulating biomarkers can be an effective tool for better stratification, prognosis and therapeutic selection/management of T2D patients. MicroRNAs (miRNAs), a class of small non-coding RNAs that modulate gene expression, have been investigated as potential circulating biomarkers in T2D. Several studies have investigated the expression of circulating miRNAs in T2D patients from various biological fluids, including plasma and serum, and have demonstrated their potential as diagnostic and prognostic biomarkers, as well as biomarkers of response to therapy. In this review, we provide an overview of the current state of knowledge, focusing on circulating miRNAs that have been consistently expressed in at least two independent studies, in order to identify a set of consistent biomarker candidates in T2D. The expression levels of miRNAs, correlation with clinical parameters, functional roles of miRNAs and their potential as biomarkers are reported. A systematic literature search and assessment of studies led to the selection and review of 10 miRNAs (miR-126-3p, miR-223-3p, miR-21-5p, miR-15a-5p, miR-24-3p, miR-34a-5p, miR-146a-5p, miR-148a-3p, miR-30d-5p and miR-30c-5p). We also present technical challenges and our thoughts on the potential validation of circulating miRNAs and their application as biomarkers in the context of T2D.

Insulin secretion and action affect glucose variability in the early stages of glucose intolerance

AIMS

Since it is unknown whether glucose variability (GV) is increased and whether this is related to worsening of insulin secretion and action in prediabetes, we have assessed insulin secretion and sensitivity, and daily GV in early stages of dysglycemia.

MATERIALS AND METHODS

Twenty subjects with normal glucose tolerance (NGT; age 45.0 ± 9.5 years; BMI 31.1 ± 6.4 kg/m2), 25 with NGT and 1hrOGTT>8.6 mmol/L (1hrOGTT; 45.7 ± 8.5 years; 32.4 ± 7.0 kg/m2), and 59 with isolated impaired glucose tolerance (iIGT; 47.7 ± 11.2 years; 31.3 ± 6.1 kg/m2) underwent OGTT and MMTT. CGM was performed with blinded FreeStyle Libre Pro for 24 h under standard conditions. Parameters of beta-cell function, insulin sensitivity and GV were calculated.

RESULTS

Overall insulin secretion and action as well as GV progressively worsened across glucose tolerance categories. On a matrix analysis, GV parameters were inversely related to ISSI-2; r = -0.37 to -0.52; p < 0.0001; and IGI; r = -0.28 to -0.48; p < 0.0001 for CV, SD, J-index, LI, HBGI and MAGE. Insulin secretion (IGI) and b-cell function (ISSI-2) emerged as independent contributors to GV in early stage of dysglycemia accounting for about 16%-38% of its variability.

CONCLUSIONS

Our results show that daily GV worsens already with mild impairment of glucose tolerance. The increase in GV is inversely related to insulin secretion and action.

SIRT1 rs7896005 polymorphism affects major vascular outcomes, not all-cause mortality, in Caucasians with type 2 diabetes: A 13-year observational study

AIMS

SIRT1 exerts effects on ageing and lifespan, as well cardiovascular (CV) disease risk. SIRT1 gene is very polymorph with a few tagging single nucleotide polymorphisms (SNPs) so far identified. Some SNPs, including rs7896005, were associated with type 2 diabetes (T2DM). We aimed to ascertain whether this SNP may be associated with CV disease at baseline as well with these same outcomes and all-cause mortality over a 13-year follow-up.

MATERIALS AND METHODS

Genotypes of SIRT1 gene were determined using TaqMan SNP assay.

RESULTS

Out of 905 T2DM, 9.1% had the AA genotype, 43.2% the AG, and 47.7% the GG. Hardy-Weinberg Equilibrium was met (minor allele frequency 0.306; p = 0.8899). At baseline, there was no difference across genotypes for sex, age, diabetes duration, CV risk factors, treatments, and microangiopathy. Major CV outcomes, myocardial infarction (MI), any coronary heart disease (CHD), and peripheral artery disease (PAD) were more frequent in GG than in AA/AG (p from 0.013 to 0.027), with no association with cerebrovascular events. By fully adjusted regression, GG remained independently related to major CV outcomes, MI, CHD, and PAD. Over follow-up, we recorded 258 major CV events (28.5%; AA/AG 25.2%, GG 32.2%; p = 0.014) with an adjusted hazard ratio (HR) of GG versus AA/AG of 1.296 (95% CI 1.007-1.668, p = 0.044); 169 coronary events (18.7%; AA/AG 15.4%, GG 22.2%; p = 0.006) with HR 1.522 (1.113-2.080, p = 0.008); 79 (8.7%) hospitalisation for heart failure (AA/AG 7.0%, GG 10.6%; p = 0.045) and HR 1.457 (0.919-2.309, p = 0.109); 36 PAD (4.0%; AA/AG 2.3%, GG 5.8%; p = 0.007) with HR 2.225 (1.057-4.684, p = 0.035). No association was found with cerebrovascular events, end stage renal disease, and all-cause mortality.

CONCLUSIONS

The rs7896005 SNP of SIRT1 might play a role in cardiovascular disease, mainly CHD risk in T2DM. Results call for larger association studies as well as studies to ascertain mechanisms by which this variant confers increased risk.

Effects of Intermittent Fasting on Brain Metabolism

We are facing an obesity epidemic, and obesity itself and its close companion, type 2 diabetes, are independent risk factors for neurodegeneration. While most medical treatments fail to induce a clinically meaningful improvement in neurodegenerative disorders, lifestyle interventions have emerged in the spotlight. A recently rediscovered approach is intermittent fasting (IF), which, compared to the classic caloric restriction regimens, limits only the time of eating, rather than the number of calories allowed per day. There is already a large amount of evidence from preclinical and clinical studies showing the beneficial effects of IF. In this review, we specifically focus on the effects of IF on brain metabolism. Key molecular players modified during IF and involved in its beneficial central effects (ketone bodies, BDNF, GABA, GH/IGF-1, FGF2, sirtuin-3, mTOR, and gut microbiota) are identified and discussed. Studies suggest that IF induces several molecular and cellular adaptations in neurons, which, overall, enhance cellular stress resistance, synaptic plasticity, and neurogenesis. Still, the absence of guidelines regarding the application of IF to patients hampers its broad utilization in clinical practice, and further studies are needed to improve our knowledge on the different IF protocols and long-term effects of IF on brain metabolism before it can be widely prescribed.

Efficacy of Dulaglutide in a Patient With Type 2 Diabetes, High Cardiovascular Risk, and HIV: A Case Report

BACKGROUND

Type 2 diabetes (T2D) is a common comorbidity in people living with HIV (PLWH). Anti-hyperglycemic treatment in PLWH is still a challenge, and no randomized controlled studies using new glucose-lowering agents are currently available.

CASE DESCRIPTION

A 55-year-old-women was admitted to our Diabetes Unit because of hyperosmolar hyperglycemic state (HHS) and sepsis. The medical history included HIV infection and insulin-treated diabetes. On clinical examination, the lady appeared dehydrated with dry buccal mucosa, tachycardia, altered mental status, genital infection, and fever. On admission, plasma glucose was 54.5 mmol/L, HbA1c 155 mmol/mol, osmolarity 389.4 mOsm/kg, bicarbonate 24.6 mmol/L with no detectable serum ketones. The patient was treated with i.v. fluid and insulin, and antibiotic therapy commenced. Upon HHS and sepsis resolution, a basal-bolus insulin therapy was implemented that was followed by significant improvement of daily glucose profiles and progressive reduction of insulin requirement until complete discontinuation. A low dose of metformin plus linagliptin was started. Since a severe atherosclerotic disease was diagnosed, a GLP-1 receptor agonist, dulaglutide, was added to metformin upon linagliptin withdrawal with maintenance of good glycemic control, treatment adherence and amelioration of quality of life and no side effects.

CONCLUSION

This case suggests that GLP-1 receptor agonist therapy may be effective and safe for treatment of T2D with high cardiovascular risk in PLWH, supporting the need of clinical trials directly assessing the safety and the efficacy of GLP-1 receptor agonist in these individuals.

Breaking Therapeutic Inertia With Alirocumab in an 80-Year-Old Patient With Severe Hypercholesterolemia: A Case Report

Background: Therapeutic inertia, defined as the failure to initiate or intensify therapy in a timely manner as per evidence-based clinical guidelines, is an important barrier limiting optimal care in the elderly. Therefore, overcoming therapeutic inertia is the core challenge when dealing with geriatric patients.

Case Description: The patient was an 80-year-old man that attended our Outpatient Lipid Clinic (Pisa University Hospital) because of persistent high LDL cholesterol (LDLc) levels in a setting of a statin contraindication. He underwent five percutaneous coronary angioplasties with drug-eluting stents. In 2014, upon starting treatment with rosuvastatin for LDLc level of 7.59 mmol/L, the patient was admitted to the Emergency Room for a presumptive diagnosis of rhabdomyolysis (creatine kinase 6685 U/L) secondary to statin. Patient developed acute kidney injury treated with dialysis. After resolution, he was discharged with ezetimibe (10 mg daily). This treatment however failed to effectively reduce LDLc levels that ranged between 5.9 and 6.6 mmol/L for the ensuing 4-years. In 2018, at the time of our evaluation, in consideration of the age, we performed a comprehensive geriatric assessment that showed good functional and mental status supporting a reliable treatment with a proprotein convertase subtilisin–kexin type 9 inhibitor. Therefore, alirocumab was prescribed as add-on to ezetimibe. At 24-month follow-up, the geriatric assessment showed no significant changes, and alirocumab was well-tolerated. LDLc was 82% lower as compared to baseline values (from 6.6 to 1.2 mmol/L).

Conclusions: This report describes a case of therapeutic inertia despite a very high-risk profile. It is also instrumental in highlightening that appropriate intensification of therapy in an elderly patient at high cardiovascular risk, by means of a patient-centered approach, may allow reaching therapeutic targets and overcoming the condition of therapeutic inertia.

Impact of COVID-19 lockdown on glucose control of elderly people with type 2 diabetes in Italy

AIMS

to evaluate the effect of home confinement related to COVID-19 lockdown on metabolic control in subjects with T2DM in Italy.

METHODS

we evaluated the metabolic profile of 304 individuals with T2DM (65% males; age 69 ± 9 years; diabetes duration 16 ± 10 years) attending our Diabetes Unit early at the end of lockdown period (June 8 to July 7, 2020) and compared it with the latest one recorded before lockdown.

RESULTS

There was no significant difference in fasting plasma glucose (8.6 ± 2.1 vs 8.8 ± 2.5 mmol/L; P = 0.353) and HbA1c (7.1 ± 0.9 vs 7.1 ± 0.9%; P = 0.600) before and after lockdown. Worsening of glycaemic control (i.e., ΔHbA1c ≥ 0.5%) occurred more frequently in older patients (32.2% in > 80 years vs 21.3% in 61-80 years vs 9.3% in < 60 years; P = 0.05) and in insulin users (28.8 vs 16.5%; P = 0.012). On multivariable analysis, age > 80 years (OR 4.62; 95%CI: 1.22-16.07) and insulin therapy (OR 1.96; 95%CI: 1.10-3.50) remained independently associated to worsening in glycaemic control.

CONCLUSIONS

Home confinement related to COVID-19 lockdown did not exert a negative effect on glycaemic control in patients with T2DM. However, age and insulin therapy can identify patients at greatest risk of deterioration of glycaemic control.

Type 1 diabetes and COVID-19: The "lockdown effect"

AIMS

The aim of this study was to evaluate the effect the lockdown imposed during COVID-19 outbreak on the glycemic control of people with Type 1 diabetes (T1D) using Continuous (CGM) or Flash Glucose Monitoring (FGM).

MATERIALS AND METHODS

We retrospectively analyzed glucose reading obtained by FGM or CGM in T1D subjects. Sensor data from 2 weeks before the lockdown (Period 0, P₀), 2 weeks immediately after the lockdown (period 1, P₁), in mid-lockdown (Period 2, P₂) and immediately after end of lockdown (Period 3, P₃) were analyzed.

RESULTS

The study included 63 T1D patients, (FGM: 52, 82%; CGM:11, 18%). Sensor use (91%) were slightly reduced. Despite this reduction, Time in Range increased in P₁ (62%), P₂ (61%) and P₃ (62%) as compared to P₀ (58%, all p < 0.05 or less) with concomitant reduction in the Time Above Range (P₀: 38%; P₁: 34%, P₂: 34%, P₃: 32%, all p < 0.05 or less vs. P₀). Average glucose and GMI improved achieving statistical difference in P₃ (165 vs. 158 mg/dl, p = 0.040 and 7.2% (55 mmol/mol) vs. 7.0% (53 mmol/mol), p = 0.016) compared to P0. Time Below Range (TBR) and overall glucose variability remained unchanged. Bi-hourly analysis of glucose profile showed an improvement particularly in the early morning hours.

CONCLUSIONS

In T1D subjects with good glycemic control on CGM or FGM, the lockdown had no negative impact. Rather a modest but significant improvement in glycemic control has been recorded, most likely reflecting more regular daily life activities and reduces work-related distress.

Increase in endogenous glucose production with SGLT2 inhibition is attenuated in individuals who underwent kidney transplantation and bilateral native nephrectomy

AIMS/HYPOTHESIS

The glucosuria induced by sodium-glucose cotransporter 2 (SGLT2) inhibition stimulates endogenous (hepatic) glucose production (EGP), blunting the decline in HbA_1c. We hypothesised that, in response to glucosuria, a renal signal is generated and stimulates EGP. To examine the effect of acute administration of SGLT2 inhibitors on EGP, we studied non-diabetic individuals who had undergone renal transplant with and without removal of native kidneys.

METHODS

This was a parallel, randomised, double-blind, placebo-controlled, single-centre study, designed to evaluate the effect of a single dose of dapagliflozin or placebo on EGP determined by stable-tracer technique. We recruited non-diabetic individuals who were 30-65 years old, with a BMI of 25-35 kg/m² and stable body weight (±2 kg) over the preceding 3 months, and HbA_1c <42 mmol/mol (6.0%). Participants had undergone renal transplant with and without removal of native kidneys and were on a stable dose of immunosuppressive medications. Participants received a single dose of dapagliflozin 10 mg or placebo on two separate days, at a 5- to 14-day interval, according to randomisation performed by our hospital pharmacy, which provided dapagliflozin and matching placebo, packaged in bulk bottles that were sequentially numbered. Both participants and investigators were blinded to group assignment.

RESULTS

Twenty non-diabetic renal transplant patients (ten with residual native kidneys, ten with bilateral nephrectomy) participated in the study. Dapagliflozin induced greater glucosuria in individuals with residual native kidneys vs nephrectomised individuals (8.6 ± 1.1 vs 5.5 ± 0.5 g/6 h; p = 0.02; data not shown). During the 6 h study period, plasma glucose decreased only slightly and similarly in both groups, with no difference compared with placebo (data not shown). Following administration of placebo, there was a progressive time-related decline in EGP that was similar in both nephrectomised individuals and individuals with residual native kidneys. Following dapagliflozin administration, EGP declined in both groups, but the differences between the decrement in EGP with dapagliflozin and placebo in the group with bilateral nephrectomy (Δ = 1.11 ± 0.72 μmol min^-1 kg^-1) was significantly lower (p = 0.03) than in the residual native kidney group (Δ = 2.56 ± 0.33 μmol min^-1 kg^-1). In the population treated with dapagliflozin, urinary glucose excretion was correlated with EGP (r = 0.34, p < 0.05). Plasma insulin, C-peptide, glucagon, prehepatic insulin:glucagon ratio, lactate, alanine and pyruvate concentrations were similar following placebo and dapagliflozin treatment. β-Hydroxybutyrate increased with dapagliflozin treatment in the residual native kidney group, while a small increase was observed only at 360 min in the nephrectomy group. Plasma adrenaline (epinephrine) did not change after dapagliflozin and placebo treatment in either group. Following dapagliflozin administration, plasma noradrenaline (norepinephrine) increased slightly in the residual native kidney group and decreased in the nephrectomy group.

CONCLUSIONS/INTERPRETATION

In nephrectomised individuals, the hepatic compensatory response to acute SGLT2 inhibitor-induced glucosuria was attenuated, as compared with individuals with residual native kidneys, suggesting that SGLT2 inhibitor-mediated stimulation of hepatic glucose production via efferent renal nerves occurs in an attempt to compensate for the urinary glucose loss (i.e. a renal-hepatic axis).

TRIAL REGISTRATION

ClinicalTrials.gov NCT03168295 FUNDING: This protocol was supported by Qatar National Research Fund (QNRF) Award No. NPRP 8-311-3-062 and NIH grant DK024092-38. Graphical abstract.

Invited review. Series: Implications of the recent CVOTs in type 2 diabetes: Which patients for GLP-1RA or SGLT-2 inhibitor?

Large cardiovascular outcome trials (CVOTs) have lent support to a cardiovascular protection with the use of SGLT2-inhibitors (SGLT2is) and GLP1-Receptor Agonists (GLP1-RAs) in subjects with type 2 diabetes. These two classes of novel glucose lowering agents have been shown to have a similar effect on the risk reduction of Major Adverse Cardiovascular Events (MACE: nonfatal myocardial infarction, nonfatal stroke, cardiovascular mortality). Nonetheless, they may not be simply interchangeable. Rather, careful evaluation of all the results of CVOTs leads identification of different effects that may allow profiling of the ideal individuals with T2DM who may benefit most from the use of one or the other class of agents. These differences include effect on heart failure, stroke and diabetic kidney disease that have prompt recent guidelines and recommendation for the treatment of type 2 diabetes to suggest the preferential use of SGLT2is in those with evidence of heart failure and impaired kidney function, while both SGLT2i and GLP1-RAs with proven effect could be use in those with prevalent atherosclerotic cardiovascular disease. This review discusses all these elements of differentiation along with others that in the future may help establishing the best cardiorenal benefit for individuals with T2DM.

Effects of treatment with metformin and/or sitagliptin on beta-cell function and insulin resistance in prediabetic women with previous gestational diabetes

AIM

To investigate the effect of sitagliptin (SITA) and metformin (MET) monotherapy as well as in combination (MET+SITA) on beta-cell function and insulin sensitivity in women with recent gestational diabetes (GDM) and impaired glucose regulation (IGR: impaired fasting glucose and/or impaired glucose tolerance).

MATERIAL AND METHODS

Forty women were randomly assigned to receive SITA (100 mg qd), MET (850 mg bid) or MET+SITA (50 + 850 mg bid) for 16 weeks. A 75 g oral glucose tolerance test (OGTT) and +125 mg/dL hyperglycaemic clamp followed by 5 g i.v. L-arginine were performed at baseline and end of study. The primary outcome of the study was the mean change in arginine-stimulated insulin secretion rate during the hyperglycaemic clamp test from baseline to 16-week therapy.

RESULTS

At week 16, body mass index declined in all groups (-1.2 ± 0.2 kg/m² ; P < 0.05). MET+SITA gave a greater increase of first phase_{(2-10 min)} insulin secretion and arginine-stimulated response (720.3 ± 299.0 to 995.5 ± 370.3 pmol/L and 3.2 ± 0.6 to 4.8 ± 1.0 pmoL/min, respectively, both P < 0.05) compared with MET and SITA. Similarly, MET+SITA was more effective in increasing OGTT-based glucose sensitivity (55.7 ± 11.3 to 108 ± 56.2 pmol x min^-1 m^-2 x mM^-1 ; P = 0.04) and insulin-stimulated glucose disposal (M/I: 2.2 ± 0.5 to 4.6 ± 1.3 mg/kg/min÷μIU/min/ml; P = 0.04; Matsuda index [SI]: 3.1 ± 0.4 to 5.7 ± 1.1; P = 0.03) compared with either MET or SITA. Disposition index (ISSI-2) increased with MET+SITA and SITA (both P < 0.05), while no significant change was observed in MET. Among MET+SITA women, 33% reverted to normal glucose tolerance (NGT) compared with 14% with MET and 7% with SITA (P < 0.05).

CONCLUSION

This study shows that MET+SITA is superior to SITA and MET monotherapy regarding beta-cell function and insulin sensitivity improvement in IGR women with previous GDM, and may offer a potential pharmacologic intervention to reduce the risk of type 2 diabetes in this high-risk population.

Nesidioblastosis and Insulinoma: A Rare Coexistence and a Therapeutic Challenge

Background: Nesidioblastosis and insulinoma are disorders of the endocrine pancreas causing endogenous hyperinsulinemic hypoglycemia. Their coexistence is very unusual and treatment represents a still unresolved dilemma. Case Description: The patient was a 43-year-old Caucasian woman, with a 2-year history of repeated severe hypoglycemic events. The diagnostic work-up was strongly suggestive of insulinoma and the patient was submitted to surgical treatment carried out laparoscopically under robotic assistance. However, surgical exploration and intraoperative ultrasonography failed to detect a pancreatic tumor. Resection was therefore carried out based on the results of selective intra-arterial calcium stimulation test, following a step-up approach, eventually leading to a pancreatoduodenectomy at the splenic artery. The histopathology examination and the immunohistochemical staining were consistent with adult-onset nesidioblastosis. After surgery, the patient continued to experience hypoglycemia with futile response to medical treatments (octreotide, calcium antagonists, diazoxide, and prednisone). Following multidisciplinary evaluation and critical review of a repeat abdominal computed tomography scan, a small nodular lesion was identified in the tail of the pancreas. The nodule was enucleated laparoscopically and the pathological examination revealed an insulinoma. In spite of the insulinoma resection, glycemic values were only partially restored, with residual nocturnal hypoglycemia. Administration of uncooked cornstarch (1.25 g/kg body weight) at bedtime was associated with significant improvement of interstitial glucose levels (p < 0.0001) and reduction of nocturnal hypoglycemia episodes (p = 0.0002). Conclusions: This report describes a rare coexistence of adult-onset nesidioblastosis and insulinoma, suggesting the existence of a wide and continuous spectrum of proliferative β-cell changes. Moreover, we propose that uncooked cornstarch may offer an additional approach to alleviate the hypoglycemic episodes when surgery is impracticable/unaccepted.

Altered Visual Plasticity in Morbidly Obese Subjects

Growing evidence indicates a close link between energy metabolism and neural plasticity as obesity is associated with alterations of cognitive functions, memory, and hippocampal neurogenesis. However, it is still unknown whether obesity can affect low-level sensory plasticity. Here we investigated this issue by probing early visual plasticity induced by short-term (2 h) monocular deprivation in a group of adult volunteers with a wide range of Body Mass Index (BMI), from normal weight to morbid obesity. We found that the effect of monocular deprivation decreased with increasing BMI, and morbidly obese subjects (BMI>40) failed to show the homeostatic plasticity effect seen in normal-weight participants. In addition, morbidly obese subjects exhibited altered binocular rivalry dynamics compared with normal-weight observers. These results show for the first time that the impact of obesity observed at the neural and cognitive level extends to basic sensory processing and plasticity.

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Cognitive decline occurs in obesity suggesting altered high-level brain plasticity

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Low-level sensory plasticity in adults declines with increasing body mass index

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Morbidly obese subjects show altered visual plasticity and interocular interactions

The Effects of Dapagliflozin on Systemic and Renal Vascular Function Display an Epigenetic Signature

CONTEXT

Mechanisms mediating the cardiovascular and renal protection exerted by SGLT2 inhibitors are still partially unknown. We investigated whether dapagliflozin modulates systemic and renal vascular function and structure, and induces epigenetic modifications.

SUBJECTS AND METHODS

Forty hypertensive patients with type 2 diabetes were randomly assigned to 4-week treatment with dapagliflozin 10 mg or hydrochlorothiazide (HCT) 12.5 mg. Routine analyses; plasma renin activity; aldosterone, catecholamine, and 24-hour urinary electrolyte levels; flow-mediated dilation (FMD) of the brachial artery; carotid-femoral pulse-wave velocity (PWV); augmentation index; and resistive index and dynamic renal resistive index (DRIN) were measured at baseline and after treatment. Circulating miRNAs (miRs) related to heart failure (miR30e-5p, miR199a-3p), endothelial dysfunction (miR27b and miR200b), and renal function (miR130b-3p, miR21-5p) were assessed and related to the effects of treatments.

RESULTS

Dapagliflozin and HCT marginally lowered blood pressure. Fasting glucose was lowered, whereas 24-hour diuresis, glycosuria, and osmolar clearance were increased by dapagliflozin (P < 0.001 for all), without affecting sodium excretion and glomerular filtration rate. Magnesium levels significantly increased after dapagliflozin treatment (P = 0.02). Neither dapagliflozin nor HCT modified FMD or PWV. DRIN did not vary in the dapagliflozin group, whereas it increased in the HCT group (P = 0.047 for time by treatment interaction). Both treatments induced variations in the expression of some miRs; dapagliflozin, but not HCT, significantly up-regulated miR30e-5p and downregulated miR199a-3p.

CONCLUSION

A putative epigenetic regulation of the protecting cardiovascular effect exerted by SGLT2 inhibitors was found. Dapagliflozin might exert nephroprotection by preserving renal vasodilating capacity.

Body Perfusion during Adult Cardiopulmonary Bypass is Improved by Pulsatile flow with Intra-Aortic Balloon Pump

Purpose

To evaluate if the use of an intra-aortic balloon pump (IABP) during cardioplegic arrest improves body perfusion.

Methods

158 coronary artery bypass graft (CABG) patients were randomized to linear cardiopulmonary bypass (CPB) (n=71, Group A) or automatic 80 bpm intra-aortic ballon pump (IABP) induced pulsatile CPB (n=87, Group B). We evaluated hemodynamic response by Swan-Ganz catheter, inflammation by cytokines, coagulation and fibrinolysis, transaminase, bilirubin, amylase, lactate and renal function (estimated glomerular filtration rate (eGFR), creatinine, and incidence of renal insufficiency and failure).

Results

IABP induced Surplus Hemodynamic Energy was 15.8±4.9 mmHg, with higher mean arterial pressure during cross-clamping (p=0.001), and lower indexed systemic vascular resistances during cross-clamping (p=0.001) and CPB discontinuation (p=0.034). IL-2 and IL-6 were lower, while IL-10 proved higher in Group B (p<0.05). Group B showed lower chest drainage (p<0.05), transfusions (p<0.05), INR (p<0.05), and AT-III (p=0.001), together with higher platelets, aPTT (p<0.05), fibrinogen (p<0.05) and D-dimer (p<0.05). Transaminases, bilirubin, amylase, lactate were lower in Group B (p<0.05); eGFR was better in Group B from ITU-arrival to 48 hours, both in preoperative kidney disease Stages 1–2 (p<0.03) and Stage 3 (p<0.05), resulting in lower creatinine from ITU-arrival to 48 hours (p<0.03). Incidence of renal insufficiency (p=0.004) and need for renal replacement therapy (p=0.044) was lower in Group B Stage 3. Group B PaO2/FiO2 and lung compliance improved from aortic declamping to the first day (p<0.003) with shorter intubation time (p=0.01).

Conclusion

Pulsatile flow by IABP improves whole-body perfusion during CPB.

Metabolic regulation of GLP-1 and PC1/3 in pancreatic α-cell line

Background and aims

An intra-islet incretin system has been recently suggested to operate through modulation of the expression and activity of proconvertase 1/3 and 2 (PC1/3, PC2) in pancreatic alpha-cell accounting for local release of GLP-1. Little is known, whether this alpha-cell activity can be affected by the metabolic alterations occurring in type 2 diabetes, such as hyperglycemia, hyperlipidemia or hyperglucagonemia.

Materials and methods

AlphaTC1/6 cells from a mice pancreatic cell line were incubated in the presence of two glucose (G) concentration (5.5 and 16.7 mM) for 16 h with or without free fatty acid, IL6 or glucagon. GLP-1 secretion was measured by ELISA and expression of PC1/3 and PC2 by RT-PCR and western blot; cell viability was determined by MTT method, Reactive Oxygen Species generation (ROS) by H₂DCFDA fluorescence and apoptosis by Annexin staining and Propidium Iodine (PI) fluorescence.

Results

Upon 16.7G incubation, GLP-1 secretion (total and active) was significantly increased in parallel with a significant increment in PC1/3 expression, a slight increase in cell viability and ROS generation and by a decrement in PC2 expression with no change in cell apoptosis. When cells were incubated at 5.5mM glucose with FFA, also an increment in GLP-1 secretion and PC1/3 expression was observed together an increment in ROS generation, a decrement in cell viability, and a modest increment in apoptosis. When incubated with 16.7mM glucose with FFA, the increment in GLP-1 secretion was reduced to basal, accompanied by an increment in apoptosis and ROS generation. This was also observed with IL-6, but in this case, no modification in ROS generation or apoptosis was observed when compared to 16.7mM glucose. The presence of glucagon did not modify any of the parameters studied.

Conclusion

These data suggest that under hyperglycemic, hyperlipidemia or inflammatory conditions, alpha cells can increase expression PC1/3 and activate GLP-1 secretion, which may contribute protecting both alpha and beta-cells from glucose and lipotoxicity, while this effect seems to be lost in the presence of both pathophysiological conditions.

Heterozygosity for the rs696217 SNP in the Preproghrelin Gene Predicts Weight Loss After Bariatric Surgery in Severely Obese Individuals

BACKGROUND

Several patients encompass a scarce weight loss after Roux-en-Y gastric bypass (RYGB). As such event is not related to surgical complications, finding markers able to identify "well responders" and to predict weight loss outcome is clinically relevant. Ghrelin regulates appetite and energy balance. Common single nucleotide polymorphisms (SNPs) in its encoding genes have been associated with body weight regulation. Other peptides involved in satiety modulation, like the CD40/CD40L complex, are less explored.

METHODS

One hundred, otherwise healthy, obese subjects (aged 45 ± 11 years, 65 females, BMI 48.0 ± 0.7 kg/m²) were sequentially enrolled in years 2014-2015. SNPs rs2241766 for adiponectin gene, rs490683 for ghrelin receptor, rs696217 and rs27647 for the preproghrelin/ghrelin gene, and rs1126535 for the CD40L gene were determined on DNA extracted from circulating lymphomonocytes. Patients were reevaluated at 6 (n = 100), 26 (n = 91), and 52 weeks (n = 79) after RYGB.

RESULTS

Subjects carrying the rs696217 T allele encompassed a significantly greater reduction in BMI 52 weeks after surgery (GG vs GT 30.5 ± 1.1 vs 38.1 ± 2.1 %; p < 0.001). Carrying the rs1126535 C allele in the CD40L gene was associated with a significantly lower BMI reduction at week 52 (TT vs CT 33.2 ± 1.1 vs 28.1 ± 2.3 %, p = 0.049). rs490683 and rs27647 SNPs of ghrelin and rs2241766 for adiponectin gene did not show any difference between carriers and non-carriers of the mutant allele.

CONCLUSION

Carrying a G to T substitution in rs696217 (preproghrelin gene) seems to mark a successful weight loss outcome; we also report for the first time that the rs1126535 C allele (CD40L gene) may predict a worse response to bariatric surgery.

Evidence for two distinct phenotypes of chronic kidney disease in individuals with type 1 diabetes mellitus

AIMS/HYPOTHESIS

In a retrospective, observational, cross-sectional, single-centre study, we assessed the prevalence and correlates of different CKD phenotypes (with and without albuminuria) in a large cohort of patients of white ethnicity with type 1 diabetes.

METHODS

From 2001 to 2009, 408 men and 369 women with type 1 diabetes (age 40.2 ± 11.7 years, diabetes duration 19.4 ± 12.2 years, HbA_1c 7.83 ± 1.17% [62.0 ± 12.9 mmol/mol]) were recruited consecutively. Albumin-to-creatinine ratio (ACR) and eGFR (Modification of Diet in Renal Disease) were obtained for all individuals, together with CKD stage. Diabetic retinopathy and peripheral polyneuropathy were detected in 41.5% and 8.1%, respectively, and cardiovascular disease (CVD) occurred in 8.5%. Adjudications of CKD phenotype were made by blinded investigators.

RESULTS

Normo- (ACR <3.4), micro- (ACR 3.4-34) or macroalbuminuria (ACR ≥34 mg/mmol) were present in 91.6%, 6.4% and 1.9% of individuals, respectively. eGFR categories 1 (≥90 ml min^-1 [1.73 m]^-2), 2 (60-89 ml min^-1 [1.73 m]^-2) and 3 (<60 ml min^-1 [1.73 m]^-2) were present in 57.3%, 39.0% and 3.7%, respectively. The majority of participants had no CKD (89.4%), while stages 1-2 and ≥3 CKD were detected in 6.8% and 3.7%, respectively. The albuminuric (Alb⁺) and non-albuminuric (Alb^-) phenotypes were present in 12 (41.4%) and 17 (58.6%) individuals with stage ≥3 CKD, respectively. Individuals with an ACR <3.4 mg/mmol were subdivided into those with normal albuminuria (<1.1 mg/mmol; 77.2%) and mildly increased albuminuria (1.1-3.4 mg/mmol; 14.4%), and individuals with stage 2 CKD were subdivided into those with eGFR 75-89 ml min^-1 [1.73 m]^-2 and 60-74 ml min^-1 [1.73 m]^-2. ACR <3.4 mg/mmol (88.7%) and even <1.1 mg/mmol (70.4%) were common in individuals with eGFR 60-74 ml min^-1 [1.73 m]^-2. The prevalence of ACR <1.1 mg/mmol was lower but still significant (34.5%) in those with stage ≥3 CKD. In logistic regression analysis, stages 1-2 and ≥3 CKD were independently associated with age, HbA_1c, γ-glutamyltransferase, fibrinogen, hypertension, but not with sex, BMI, smoking, HDL-cholesterol or triacylglycerol. Inclusion of advanced retinopathy removed HbA_1c from the model. The CKD Alb⁺ phenotype correlated with diabetes duration, HbA_1c, HDL-cholesterol, fibrinogen and hypertension, while the CKD Alb^- phenotype was associated with age and hypertension, but not with diabetes duration, HbA_1c and fibrinogen.

CONCLUSIONS/INTERPRETATION

The Alb^- CKD phenotype is present in a significant proportion of individuals with type 1 diabetes supporting the hypothesis of two distinct pathways (Alb⁺ and Alb^-) of progression towards advanced kidney disease in type 1 diabetes. These are probably distinct pathways as suggested by different sets of covariates associated with the two CKD phenotypes.

Early Combination Therapy with Oral Glucose-Lowering Agents in Type 2 Diabetes

Despite the considerable burden of disease associated with type 2 diabetes mellitus (T2DM), most patients are not at, or are unable to achieve, recommended glycemic targets. This is partly because of the relentless progressive nature of the disease, but it may also be attributable to the current diabetes treatment paradigm. The recommended stepwise approach may lead to frequent early treatment failure with prolonged periods of elevated glucose as a consequence of clinical inertia and delays in achieving optimal glycemic control. Thus, it is most appropriate to consider the current treatment paradigm for T2DM in the context of a more aggressive initial therapy with early combination therapy. Current guidelines advise that initial combination therapy should be used for patients presenting with elevated glycated hemoglobin (HbA_1c). However, several studies and recent meta-analyses suggest a potential benefit from initial combination therapy on glycemic outcomes in diabetes compared with metformin monotherapy across a wide range of baseline HbA_1c levels. Indeed, combination therapy can increase the number of patients achieving glycemic goals, and the newer glucose-lowering agents may reduce the risk of hypoglycemia and body weight gain. Moreover, our improving understanding of the complex pathophysiology of T2DM and the availability of treatments tackling specific mechanisms contributing to hyperglycemia should lead to more pathophysiologically sound combination therapy. We discuss the rationale behind and evidence for early combination therapy as well as what is needed in the future to better understand its potential.

Access to emergency room for hypoglycaemia in people with diabetes

BACKGROUND

Hypoglycaemia is a major burden of the pharmacological therapy of diabetes and is associated with increased morbidity, mortality and treatment costs.

METHODS

We screened all admissions to the emergency room of the Pisa University Hospital from 1 January 2009 to 31 December 2013, selecting individuals with a discharge diagnosis of hypoglycaemia. We retrieved 500 admissions involving adult diabetic patients: age 71 ± 16 years; M/F 50.2/49.8%; 70.2% type 2 diabetes (T2DM).

RESULTS

Among T2DM, 42.2% were on insulin, 10.8% on insulin plus oral anti-diabetes drugs and 38.2% on oral anti-diabetes drugs alone (92% sulphonylureas/glinides ± insulin-sensitizers). Glibenclamide was the most frequently used sulphonylurea (69%). Individuals treated with oral anti-diabetes drugs were older than those on insulin (79 ± 11 versus 74 ± 12 years; p < 0.0001). Among patients taking sulphonylurea, 47% had estimated glomerular filtration rate <60 mL/min/1.73 m(2) and 13.5% had <30 mL/min/1.73 m(2) . In-hospital admission occurred in 20% of cases. Hospitalized patients with T2DM were older than those discharged (80 ± 10 versus 76 ± 12 years, p < 0.01) and were on oral antidiabetic drugs in 54.8% of the cases, whereas 35.7% were on insulin (χ(2) , p < 0.0001) and 8.3% on combined therapy. Notably, 93.5% of those on oral anti-diabetic drugs were taking a secretagogue. Insulin-treated subjects were younger than those treated with oral anti-diabetic drugs alone (77 ± 12 versus 82 ± 7 years; p < 0.02). The mean in-hospital annual mortality rate was 85 deaths per 1000 patients-year.

CONCLUSIONS

Our results support the recommendation that the risk associated with insulin and insulin-secretagogues should be carefully assessed, particularly when prescribed in vulnerable patients with T2DM.

Glucose Metabolism in High-Risk Subjects for Type 2 Diabetes Carrying the rs7903146 TCF7L2 Gene Variant

CONTEXT

The mechanisms responsible for contribution of variants in the gene TFC7L2 to the risk for type 2 diabetes (T2DM) remains far from being completely understood, and available studies have generated nonunivocal results.

OBJECTIVE

We investigated the postprandial glucose metabolism in subjects at risk for T2DM carrying the TCF7L2 risk allele.

DESIGN, SETTING, AND PARTICIPANTS

Twenty-three subjects carrying the risk-conferring TCF7L2 genotypes (11 TT and 12 CT at rs7901346) and 13 subjects with wild-type genotype (CC) underwent a standard mixed-meal test (MMT) in combination with stable isotope tracers.

OUTCOME MEASUREMENTS

We evaluated endogenous and exogenous glucose fluxes and hormonal responses.

RESULTS

Fasting plasma glucose, insulin, C-peptide, glycated hemoglobin, endogenous glucose production, and plasma glucose clearance were similar in the three groups, whereas plasma glucagon levels were lower in both CT and TT than in CC (64 ± 20, 63 ± 18 and 90 ± 29 pg/mL, respectively; both P = .01). In response to the MMT, TT subjects had lower plasma glucose levels than CC subjects [mean area under the time-concentration curve (AUC) 6.1 ± 3.9 vs 7.1 ± 12.0 mmol/L, P = .04] and lower insulin secretion rate (mean AUC 385 ± 95 vs 530 ± 159 pmol/m(2) · min, P = .02). Initial (0-60 min) rate of appearance (Ra) of oral glucose was lower in TT compared with CT/CC (AUC 2.7 ± 1.1 vs 3.8 ± 1.2 μmol/kg · min, P = .02) with no difference among the three groups in endogenous glucose production. The AUC0-60min for Ra of exogenous glucose (Raex) was positively correlated with the plasma glucose AUC0-60min. Total Raex AUC0-120min was correlated with total AUC0-120min of plasma glucose (r = 0.45, P < .01). Plasma glucagon-like peptide-1 and glucose-dependent insulinotropic peptide levels in response to the MMT were not affected by genotype.

CONCLUSIONS

In subjects at risk for T2DM, the TCF7L2 polymorphisms were associated with reduced Raex into systemic circulation, causing reduced postprandial blood glucose increase and, in turn, lower insulin secretion rate with no impairment in β-cell function. The reduced Raex is likely due to greater glucose retention in the splanchnic area.

New forms of insulin and insulin therapies for the treatment of type 2 diabetes

Insulin is a common treatment option for many patients with type 2 diabetes, and is generally used late in the natural history of the disease. Its injectable delivery mode, propensity for weight gain and hypoglycaemia, and the paucity of trials assessing the risk-to-safety ratio of early insulin use are major shortcomings associated with its use in patients with type 2 diabetes. Development of new insulins-such as insulin analogues, including long-acting and short-acting insulins-now provide alternative treatment options to human insulin. These novel insulin formulations and innovative insulin delivery methods, such as oral or inhaled insulin, have been developed with the aim to reduce insulin-associated hypoglycaemia, lower intraindividual pharmacokinetic and pharmacodynamic variability, and improve imitation of physiological insulin release. Availability of newer glucose-lowering drugs (such as glucagon-like peptide-1 receptor agonists, dipeptidyl peptidase-4 inhibitors, and sodium-glucose co-transporter-2 inhibitors) also offers the opportunity for combination treatment; the results of the first trials in this area of research suggest that such treatment might lead to use of reduced insulin doses, less weight gain, and fewer hypoglycaemic episodes than insulin treatment alone. These and future developments will hopefully offer better opportunities for individualisation of insulin treatment for patients with type 2 diabetes.

Dipeptidyl peptidase-4 inhibitors can minimize the hypoglycaemic burden and enhance safety in elderly people with diabetes

The prevalence of type 2 diabetes mellitus (T2DM) among elderly people is increasing. Often associated with disabilities/comorbidities, T2DM lowers the chances of successful aging and is independently associated with frailty and an increased risk of hypoglycaemia, which can be further exacerbated by antihyperglycaemic treatment. From this perspective, the clinical management of T2DM in the elderly is challenging and requires individualization of optimum glycaemic targets depending on comorbidities, cognitive functioning and ability to recognize and self-manage the disease. The lack of solid evidence-based medicine supporting treatment guidelines for older people with diabetes further complicates the matter. Several classes of medicine for the treatment of T2DM are currently available and different drug combinations are often required to achieve individualized glycaemic goals. Many of these drugs, however, carry disadvantages such as the propensity to cause weight gain or hypoglycaemia. Dipeptidyl peptidase-4 (DPP-4) inhibitors, a recent addition to the pharmacological armamentarium, have become widely accepted in clinical practice because of their efficacy, low risk of hypoglycaemia, neutral effect on body weight, and apparently greater safety in patients with kidney failure. Although more information is needed to reach definitive conclusions, growing evidence suggests that DPP-4 inhibitors may become a valuable component in the pharmacological management of elderly people with T2DM. The present review aims to delineate the potential advantages of this pharmacological approach in the treatment of elderly people with T2DM.

Insulin degludec/insulin aspart combination for the treatment of type 1 and type 2 diabetes

Glycemic control remains the major therapeutic objective to prevent or delay the onset and progression of complications related to diabetes mellitus. Insulin therapy represents a cornerstone in the treatment of diabetes and has been used widely for achieving glycemic goals. Nevertheless, a large portion of the population with diabetes does not meet the internationally agreed glycemic targets. Moreover, insulin treatment, especially if intensive, may be associated with emergency room visits and hospitalization due to hypoglycemic events. Therefore, fear of hypoglycemia or hypoglycemic events represents the main barriers to the attainment of glycemic targets. The burden associated with multiple daily injections also remains a significant obstacle to initiating and maintaining insulin therapy. The most attractive insulin treatment approach should meet the patients’ preference, rather than demanding patients to change or adapt their lifestyle. Insulin degludec/insulin aspart (IDegAsp) is a new combination, formulated with ultra-long-acting insulin degludec and rapid-acting insulin aspart, with peculiar pharmacological features, clinical efficacy, safety, and tolerability. IDegAsp provides similar, noninferior glycemic control to a standard basal–bolus regimen in patients with type 1 diabetes mellitus, with additional benefits of significantly lower episodes of hypoglycemia (particularly nocturnal) and fewer daily insulin injections. Moreover, although treatment strategy and patients’ viewpoint are different in type 1 and type 2 diabetes, trial results suggest that IDegAsp may be an appropriate and reasonable option for initiating insulin therapy in patients with type 2 diabetes inadequately controlled on maximal doses of conventional oral agents. This paper will discuss the role of IDegAsp combination as a novel treatment option in diabetic patients.

Optimal therapy of type 2 diabetes: a controversial challenge

Type 2 diabetes mellitus (T2DM) is one of the most common chronic disorders in older adults and the number of elderly diabetic subjects is growing worldwide. Nonetheless, the diagnosis of T2DM in elderly population is often missed or delayed until an acute metabolic emergency occurs. Accumulating evidence suggests that both aging and environmental factors contribute to the high prevalence of diabetes in the elderly. Clinical management of T2DM in elderly subjects presents unique challenges because of the multifaceted geriatric scenario. Diabetes significantly lowers the chances of "successful" aging, notably it increases functional limitations and impairs quality of life. In this regard, older diabetic patients have a high burden of comorbidities, diabetes-related complications, physical disability, cognitive impairment and malnutrition, and they are more susceptible to the complications of dysglycemia and polypharmacy. Several national and international organizations have delivered guidelines to implement optimal therapy in older diabetic patients based on individualized treatment goals. This means appreciation of the heterogeneity of the disease as generated by life expectancy, functional reserve, social support, as well as personal preference. This paper will review current treatments for achieving glycemic targets in elderly diabetic patients, and discuss the potential role of emerging treatments in this patient population.

Adipocytokines mark insulin sensitivity in euthyroid Hashimoto's patients

The relationship between inflammation, Hashimoto's thyroiditis (HT) and insulin resistance is still controversial. In this regard, a pretty complete evaluation of adipocytokines levels in patients with HT has not been performed so far. We assessed retinol binding protein-4 (RBP4), adipocyte-fatty acid binding protein (A-FABP), neutrophil gelatinase-associated lipocalin (NGAL) and tumor necrosis factor-α (TNFα) levels in 93 euthyroid HT patients and 51 healthy controls (CTL), also evaluating the possible correlation between adipocytokines levels and markers of insulin resistance. No significant differences between HT patients and CTL in fasting plasma glucose and insulin levels, and HOMA index were observed. HT patients had significantly higher RBP4, NGAL and A-FABP levels than CTL, while TNFα levels did not differ between the two groups. In HT patients, RBP4 was significantly related with fT3 and fT4 levels, while A-FABP with fT4 only. Moreover, in HT patients, either RBP4 or A-FABP was directly associated with plasma insulin and HOMA index. Circulating levels of these adipocytokines were not influenced by the presence of antithyroid peroxidase or antithyroglobulin autoantibodies or only one of them, neither by autoantibodies titer. In conclusion, euthyroid HT patients are characterized by a peculiar inflammatory response of the adipose tissue, apparently related to an early reduction in insulin sensitivity and to serum thyroid hormone levels, although within the normal range. These results suggest that HT patients with high RBP4 and A-FABP levels might deserve a particular attention, being potentially more exposed to develop insulin resistance and increased cardiovascular risk.

Soluble human leukocyte antigen-g and its insertion/deletion polymorphism in papillary thyroid carcinoma: novel potential biomarkers of disease?

INTRODUCTION

Human leukocyte antigen-G (HLA-G), a nonclassical major histocompatibility complex class I antigen, plays a pivotal role in immune tolerance and a paradoxical role in cancers.

AIMS

Our aims were to evaluate plasma soluble HLA-G (sHLA-G) concentrations and the 14-bp insertion/deletion polymorphism of the HLA-G gene in patients with papillary thyroid carcinoma (PTC) or Hashimoto's thyroiditis (HT) and to assess the possible association of these parameters with PTC aggressiveness.

METHODS

Samples for the analysis of sHLA-G and +14/-14-bp HLA-G polymorphism were obtained from 121 patients with HT and 183 with PTC; 245 gender- and age-matched healthy subjects served as controls. PTC histopathological aggressiveness was defined according to the last American Thyroid Association guidelines.

RESULTS

Positive serum antithyroid antibody titers were observed in 22% of PTC patients and lymphocyte infiltration of thyroid parenchyma at histological examination in 21%, whereas both circulating and histological autoimmunity was detectable in 12% of PTC patients. No differences in the +14/-14-bp polymorphism frequencies were observed between the study groups. The prevalence of detectable sHLA-G was lower in healthy controls (52%) as compared with both HT (57%) and PTC (62%) patients. By stratifying the study groups according to sHLA-G level of positive subjects, significantly higher plasma sHLA-G values in PTC (42.9 ± 3.3 ng/ml; P = 0.002) and HT patients (49.1 ± 2.6 ng/ml; P < 0.002) as compared with healthy controls (8.5 ± 1.8 ng/ml) were obtained. Moreover, PTC patients with detectable plasma sHLA-G levels showed a higher aggressive behavior (P < 0.04) than those without.

CONCLUSIONS

Although confirming the frequent association between PTC and chronic autoimmune thyroiditis, these data suggest that elevated circulating sHLA-G levels, besides an important signal of alterations of immune homeostasis, may be considered a potential, novel marker of PTC histopathological aggressiveness at diagnosis. Additional studies are needed to confirm the actual role and clinical relevance of the HLA-G complex in PTC development and progression.

DNMT3B promoter polymorphisms and risk of late onset Alzheimer's disease

The vast majority of Alzheimer's disease (AD) are late-onset forms (LOAD) likely due to the contribution of genetic, environmental, and stochastic factors, superimposed on a physiologically age-related decline of neuronal functions. Increasing evidence indicates epigenetic modifications in LOAD brains, and many of the environmental factors associated with AD risk, such as heavy metals and dietary factors, are able to modify the epigenome. There is also indication that environmentally-induced early life modifications of the genome during embryogenesis and brain development could contribute to the development of the disease later in life. DNA methyltransferase 3b (DNMT3b) is an enzyme involved in de novo methylation of the genome during embryogenesis, expressed in progenitor cells during neurogenesis. In the present study we evaluated two functional DNMT3B promoter polymorphisms, namely -149 C > T (rs2424913) and - 579 G > T (rs1569686), as candidate LOAD risk factors. Our analysis of 376 Italian LOAD patients and 308 matched controls revealed no difference in allele frequencies between the case an the control group (OR = 1.10 (0.88-1.39) for rs2424913, and OR = 1.02 (0.81-1.28) for rs1569686). Also the genotype distributions of both polymorphisms were closely similar between groups, and no significant effect on disease age at onset was observed. Overall, present results do not support a major role for rs2424913 or rs1569686 in LOAD pathogenesis.

The effect of Ginkgo biloba extract on genotoxic damage in patients with differentiated thyroid carcinoma receiving thyroid remnant ablation with iodine-131

BACKGROUND

Radioiodine ((131)I) therapy is usually performed in patients with differentiated thyroid cancer (DTC). Although (131)I is generally considered safe, genotoxic damage has been demonstrated both in vivo and in vitro. The aim of the current study was to evaluate the effect of Ginkgo biloba extract (GBE) on the time-course of appearance, after (131)I therapy for DTC, of plasma factors with chromosome-damaging properties (so-called "clastogenic" factors [CFs]) and of micronuclei (MN) in lymphocytes.

METHODS

Twenty-three patients (median age 42 years, range 18-73) with DTC receiving (131)I activity (3.7 GBq) for thyroid remnant ablation were randomly assigned to receive GBE (120 mg/day for one month; n=10) or placebo (n=13) in a double-blind manner. Blood samples were taken at various intervals (from baseline to 90 days) after (131)I therapy. The frequency of MN in blood lymphocytes was determined, and CFs were assayed in plasma by a method that used MN increase in lymphocytes from an healthy donor as the endpoint of the assay.

RESULTS

MN in blood lymphocytes increased significantly after (131)I treatment in the placebo group, peaking at the 7th day (p=0.002) and slowly declining thereafter. In contrast, in similarly treated patients who were also treated with GBE both before and after (131)I treatment, a significant increase of blood lymphocyte MN level was not observed. In addition, only the placebo group showed a significant, progressive increase in CFs activity. This peaked at the 14th day (p=0.003 vs. baseline) and was still noted for the last plasma sample. The differences in the change in lymphocyte MN and CFs activity between the placebo and GBE-treated groups were significant (p<0.01 and p<0.05, respectively). Thyroid function tests, including serum thyroglobulin (Tg) and anti-Tg antibody levels, were never significantly different.

CONCLUSIONS

GBE may protect from possible oxidative and genotoxic damage associated with (131)I treatment in patients requiring (131)I therapy for thyroid cancer, without affecting the clinical outcome. Further studies with larger cohorts of patients are needed to confirm this report and verify the beneficial effect of GBE in patients requiring (131)I therapy, particularly for those in whom repeated treatments and high activities of (131)I are required.

The emerging role of sunitinib in the treatment of advanced epithelial thyroid cancer: our experience and review of literature

Tyrosine kinase receptors have been shown to play an important role in epithelial thyroid tumor growth and angiogenesis. Thyroid cancers commonly present oncogene mutations involved in MAPK kinase pathway like BRAF and RET; they are also frequently dependent on VEGF stimuli. Preliminary clinical experiences suggest a promising role of sunitinib (a tyrosine kinase inhibitor) for the treatment of advanced thyroid cancers. This review deals with the available data on the effect of sunitinib in the treatment of metastatic, radioiodine refractory thyroid cancers. We also report our experience with the off-label use of sunitinib in such patients.

Is elastography actually useful in the presurgical selection of thyroid nodules with indeterminate cytology?

BACKGROUND

Although fine-needle aspiration cytology remains the mainstay of the preoperative workup of thyroid nodules, those with follicular proliferation still represent a diagnostic challenge. Real-time elastography (RTE) estimates the stiffness/elasticity of lesions and is regarded as a promising technique for the presurgical selection of thyroid nodules (including those with indeterminate cytology).

AIM

Our aim was to verify the potential role of RTE in the presurgical diagnosis of cancer in a large cohort of consecutive patients with follicular thyroid nodules.

PATIENTS AND METHODS

One hundred two patients were submitted to conventional ultrasonography and RTE evaluation before being operated on for thyroid nodule with indeterminate cytology (54% single nodules). Tissue stiffness on RTE was scored from 1 (greatest elasticity) to 4 (no elasticity).

RESULTS

At conventional ultrasonography examination, the nodules (median diameter 2.2 cm) were solid (cystic areas < 10%); microcalcifications were detected in 56% of them and a hypoechoic pattern in 64%. Elasticity was high in eight cases only (score 1-2) although low in 94 (score 3-4). Cancer was diagnosed in 36 nodules (35%), being associated with microcalcifications (P < 0.0001) and inversely related to nodule diameter (P < 0.01). Malignancy was detected in 50% of the nodules with RTE score 1-2 and in 34% of those with score 3-4. Therefore, either the positive (34%) or the negative predictive value (50%) was clinically negligible.

CONCLUSIONS

The current study does not confirm the recently reported usefulness of RTE in presurgical selection of nodules with indeterminate cytology and suggest the need for quantitative analytical assessment of nodule stiffness to improve RTE efficacy.

Fasting hyperglycaemia and in-hospital mortality in elderly population

BACKGROUND

Admission hyperglycaemia has shown to be a marker of poor clinical outcome. The prevalence of admission hyperglycaemia and its relationship with in-hospital mortality in elderly population has not been clearly defined. We assessed the prevalence and prognostic significance of admission fasting hyperglycaemia in aged patients.

METHODS

A total of 808 elderly patients were studied. Patients were classified into group I (serum glucose < 126 mg/dl), II (126-180 mg/dl) and III (> 180 mg/dl). Groups II and III were considered newly recognised fasting hyperglycaemia (NRFH) in non-diabetic patients.

RESULTS

NRFH was present in 18.6%. After excluding diabetic patients (n = 206, 25.5%), the distribution of patients (n = 602, 74.5%) was as follows: group I (n = 452, 55.9%), group II (n = 122, 15.1%) and group III (n = 28, 3.5%). In the whole cohort, median fasting glucose was lower in patients who survived [105 mg/dl (88-135)] than in those who died [127 mg/dl (93-159), p < 0.001]. This significant difference was maintained only when non-diabetic patients were considered [100 mg/dl (87-122) vs. 118 mg/dl (92-149), p < 0.001]. In-hospital mortality rate in groups I, II and III was 8.5%, 14.1% and 22.9%, respectively (p < 0.001). Mortality rate was 8.4%, 18.0% and 32.1% (p < 0.001) in groups I, II and III, respectively in non-diabetic population. Both low albumin and high glucose serum concentrations were the only independent risk factors for in-hospital all-cause mortality in non-diabetic patients.

CONCLUSIONS

In non-diabetic elderly patients admitted for acute disease, serum glucose concentration is an important, simple and independent predictor of hospital mortality.

Identification and optimal postsurgical follow-up of patients with very low-risk papillary thyroid microcarcinomas

CONTEXT

Most papillary thyroid microcarcinomas (PTMCs; ≤ 1 cm diameter) are indolent low-risk tumors, but some cases behave more aggressively. Controversies have thus arisen over the optimum postoperative surveillance of PTMC patients.

OBJECTIVES

We tested the hypothesis that clinical criteria could be used to identify PTMC patients with very low mortality/recurrence risks and attempted to define the best strategy for their management and long-term surveillance.

DESIGN

We retrospectively analyzed data from 312 consecutively diagnosed PTMC patients with T1N0M0 stage disease, no family history of thyroid cancer, no history of head-neck irradiation, unifocal PTMC, no extracapsular involvement, and classic papillary histotypes. Additional inclusion criteria were complete follow-up data from surgery to at least 5 yr after diagnosis. All 312 had undergone (near) total thyroidectomy [with radioactive iodine (RAI) remnant ablation in 137 (44%) - RAI group] and were followed up yearly with cervical ultrasonography and serum thyroglobulin, TSH, and thyroglobulin antibody assays.

RESULTS

During follow-up (5-23 yr, median 6.7 yr), there were no deaths due to thyroid cancer or reoperations. The first (6-12 months after surgery) and last postoperative cervical sonograms were negative in all cases. Final serum thyroglobulin levels were undetectable (<1 ng/ml) in all RAI patients and almost all (93%) of non-RAI patients.

CONCLUSION

Accurate risk stratification can allow safe follow-up of most PTMC patients with a less intensive, more cost-effective protocol. Cervical ultrasonography is the mainstay of this protocol, and negative findings at the first postoperative examination are highly predictive of positive outcomes.

Non-thyroidal illness syndrome and short-term survival in a hospitalised older population

BACKGROUND

non-thyroidal illness syndrome (NTIS) has been associated with an adverse clinical outcome.

OBJECTIVE

to evaluate the prevalence of NTIS, its impact on patients' survival and the possible pathogenic role of systemic inflammation.

DESIGN

observational cross-sectional analysis.

PARTICIPANTS AND SETTING

three hundred and one acutely ill older patients (156 women; median age 81 years, range 65-101) consecutively admitted to a primary care unit.

METHODS

serum FT(3), FT(4) and thyrotropin levels as well as acute inflammation indexes were evaluated.

RESULTS

the NTIS prevalence (specifically low T3 syndrome) was 31.9%. A significant association was found between NTIS and acute renal failure (P = 0.006), New York Heart Association classification (NYHA) IV heart failure (P = 0.003) and metastasised cancer disease (P = 0.0002). Serum FT(3) values correlated inversely with serum C-reactive protein (P < 0.0001), lactate dehydrogenase (P = 0.0004), fibrinogen (P = 0.03) and erythrocyte sedimentation rate (P < 0.0001) values, and progressively decreased with increasing tertiles of age (P = 0.0004). The mortality rate was significantly higher (P = 0.0002) among patients with low T3 syndrome, which emerged as the sole predictive factor of death (odds ratio 4.3; 95% confidence interval 1.7-10.5).

CONCLUSIONS

low T3 syndrome is very common in the hospitalised older population, emerging as the most sensitive independent predictor of short-term survival. Serum FT(3) determination should be included in the assessment of short-term prognosis of acutely ill older patients.

Radioiodine ablation: when and how

Differentiated thyroid cancer (DTC) is the most common endocrine malignancy with the highest mortality although with appropriate treatment has a good long-term prognosis and cure rate. Over the last 30 years there is a worldwide trend showing an increasing incidence of thyroid cancer. In DTC patients, total thyroidectomy has been for many decades routinely followed by the administration of radioiodine (131I) activity to destroy remnant thyroid tissue. Several reasons are in favour to routine ablation of postoperative thyroid remnants. The combination of both surgery and radioiodine has proven as a safe and effective treatment, resulting in improved life expectation and reduced recurrence rate for DTC patients. Recently, however, 131I ablation is not uniformly recommended for cancers smaller than 10 mm, and its use is debated for papillary tumours with diameter between 10 and 20 mm. Indeed, the decision about subsequent 131I thyroid remnant ablation is recommended as "individualized and selective". Even if new evidence has emerged that provides additional support for performing 131I treatment, the possible presence of radioiodine-associated side effects should be not overlooked. Moreover, a lot of discussion has taken place as to whether, and to what extent, 131I may cause secondary malignancies. Blood-based dosimetry is important to avoid surplus bone marrow toxicity while treating DTC patients. In this regard, the availability of a genetically engineered version of recombinant human TSH (rhTSH) provides an alternative tool to enhance serum TSH levels without inducing hypothyroidism. The administration of rhTSH to thyroid cancer patients still on LT4 therapy promotes radioiodine uptake and thyroglobulin production by thyroid cells to an extent comparable with hypothyroidism, preserving patients' quality of life, increasing the renal clearance of 131I and decreasing both the whole body and the blood dose. In this review the authors will discuss the pros and cons of postoperative radioiodine-induced thyroid remnant ablation.

Chromosome translocation frequency after radioiodine thyroid remnant ablation: a comparison between recombinant human thyrotropin stimulation and prolonged levothyroxine withdrawal

BACKGROUND

Thyroid remnant ablation of differentiated thyroid carcinoma (DTC) patients is traditionally performed after levothyroxine withdrawal. Recombinant human TSH (rhTSH) administration increases serum TSH levels without inducing hypothyroidism.

AIM

The aim of the study was to investigate the frequency of chromosome translocations in DTC patients after the first (131)I therapeutic dose and compare the frequency of translocations between DTC patients off levothyroxine and those receiving rhTSH.

PATIENTS AND METHODS

A total of 20 DTC patients were randomly assigned to levothyroxine withdrawal [(30 d) group A; n=10, nine women; mean age 48.5+/- 19.2 yr] or rhTSH injections [(0.9 mg im per 2 consecutive days) group B; n=10, eight women; mean age 50.4+/- 18.8 yr] before undergoing (131)I activity (3.7 GBq). The frequency of translocations in peripheral lymphocytes was analyzed by tricolor fluorescence in situ hybridization with whole-chromosome-specific probes for chromosomes 1, 4, and 8. Lymphocytes were stained routinely (about 500 each time).

RESULTS

The two groups showed similar baseline translocation frequency. After (131)I administration, the total chromosomal translocation rate was significantly lower in group B than group A (P = 0.02). The frequency of translocations increased significantly in group A only (P = 0.01 vs. baseline). Rearrangement specifically involved chromosomes 4 and 8 (P = 0.02 vs. baseline).

CONCLUSIONS

Our preliminary data show that in hypothyroid status (131)I ablation therapy induces a higher translocation rate, especially in chromosomes 4 and 8. This finding, in agreement with previous dosimetric reports, suggests that whereas inducing a low extrathyroid exposure, rhTSH reduces the potential risk of chromosomal aberration associated with blood irradiation.

Inflammatory response after cardiopulmonary bypass: a randomized comparison between conventional hemofiltration and steroids

AIM

Recent reports have shown anti-inflammatory effects with conventional hemofiltration (CUF) in patients undergoing cardiopulmonary bypass (CPB). The aim of this study was to evaluate the immunological and the hemodynamic response to CUF or metilprednisolone in patients undergoing coronary artery bypass grafting.

METHODS

Twenty-four consecutive patients were prospectively randomized to receive CUF (12 patients, Group A) or metilprednisolone (12 patients, Group B). Hemodynamic response was evaluated by Swan-Ganz catheter, immunological response was analyzed by IL-2, IL-4, IL-6, TNF-alpha, IFN-gamma, IL-10 before anesthetic induction (T0), at aortic-declamping (T1), at the end of surgery (T2), ITU admission (T3) and 24 hours (T4). Troponin I was measured at the same time-points. Hematological and coagulative controls were performed.

RESULTS

Morbidity and mortality were comparable between the two groups. Group A demonstrated lower cardiac index at T1 (2.1 +/- 0.69 L/min m2 vs. 3.917 +/- 1.28, P = 0.034) without significantly higher indexed-systemic-vascular-resistances at the end of surgery (1 101 +/- 434.3 dyne s cm(-5) m(-2) vs. 797.7 +/- 316.67, P = 0.233). When proinflammatory and anti-inflammatory cytokines were considered, all improved during the postoperative time course, without differences between the 2 Groups (P = NS). Hematological and coagulative data were similar in the two groups, in terms of white blood cells, platelets, prothrombin time, and activated partial thromboplastin time (P = NS).

CONCLUSIONS

Anti-inflammatory action of CUF was comparable to steroids, thus determining a similar proinflammatory response to CPB. However, hemodynamics was slightly impaired by CUF. Therefore, there is no reason to prefer CUF to steroids in patients undergoing elective CABG.

Elevated antithyroid peroxidase and antinuclear autoantibody titers in Ménière's disease patients: more than a chance association?

OBJECTIVE/HYPOTHESIS

The aim of this prospective study is to evaluate the possible association between Ménière's disease (MD) and autoantibodies.

METHODS

Fifty-five patients with definite MD (51 unilateral and 4 bilateral) were matched with 55 patients with unilateral vestibular paresis without cochlear involvement and 55 healthy subjects. Blood samples were collected from all study subjects for the determination of serum TSH, free triiodothyronine, free thyroxine, anti-TSH receptor antibody, antithyroperoxidase antibody, antithyroglobulin antibody and of antibodies to non-organ-specific antigens, namely antinuclear antibodies, antibodies to extractable nuclear antigens and antineutrophilic cytoplasmic antibodies.

RESULTS

Thirty-three subjects (60%) of the MD group had 1 or more elevated serum autoantibody levels, both organ and non-organ specific; 16 patients (29.1%) with unilateral vestibular paresis had 1 or more elevated serum autoantibody levels, while 13 healthy subjects (23.6%) had 1 or more elevated serum autoantibody levels.

CONCLUSIONS

Based on our data we speculate that there is a more than a chance association between MD and 'autoimmunity', thus suggesting a hypothetical role of the immune system in MD pathogenesis. In other words, a pathogenetic role of an 'immune dysregulation' in MD patients can be hypothesized.