Publications by authors named "Fabiana Picconi"

21 Publications

  • Page 1 of 1

Glycemic Status Assessment by the Latest Glucose Monitoring Technologies.

Int J Mol Sci 2020 Nov 3;21(21). Epub 2020 Nov 3.

Unit of Endocrinology, Diabetes and Metabolism, S. Giovanni Calibita, Fatebenefratelli Hospital, 00186 Rome, Italy.

The advanced and performing technologies of glucose monitoring systems provide a large amount of glucose data that needs to be properly read and interpreted by the diabetology team in order to make therapeutic decisions as close as possible to the patient's metabolic needs. For this purpose, new parameters have been developed, to allow a more integrated reading and interpretation of data by clinical professionals. The new challenge for the diabetes community consists of promoting an integrated and homogeneous reading, as well as interpretation of glucose monitoring data also by the patient himself. The purpose of this review is to offer an overview of the glycemic status assessment, opened by the current data management provided by latest glucose monitoring technologies. Furthermore, the applicability and personalization of the different glycemic monitoring devices used in specific insulin-treated diabetes mellitus patient populations will be evaluated.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms21218243DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7663245PMC
November 2020

Microvascular impairment as a biomarker of diabetic retinopathy progression in the long-term follow up in type 1 diabetes.

Sci Rep 2020 10 26;10(1):18266. Epub 2020 Oct 26.

Department of Ophthalmology, IRCCS-Fondazione Bietti, Rome, Italy.

This study aimed to explore differences in vascular and structural parameters using optical coherence tomography angiography in patients with type 1 diabetes (DM1) with mild signs of diabetic retinopathy (DR) over a two-year follow-up period. Parafoveal vessel density (PVD) and foveal avascular zone (FAZ) area were analyzed. The thickness of three predefined retinal slabs was measured, including the inner limiting membrane (ILM)-inner plexiform layer (IPL), IPL-inner nuclear layer (INL), and the IPL-outer nuclear layer (ONL). Twenty-two patients with DM1 and 21 controls were included. There was no significant difference in the FAZ area, perimeter and acircularity index between cohorts over time. Baseline superficial capillary plexus PVD was approximately 10% lower in patients with diabetes than in controls (p = 0.001), and was 12% lower at 2 years (p = 0.002). There was no difference in the annual linear trend between the groups (- 0.5% in diabetics vs. controls, p = 0.736). Baseline deep capillary plexus (DCP) PVD was slightly lower in diabetics than in controls (- 4.4%, p = 0.047) and the difference increased at 2 years (- 12.6%, p < 0.001). The annual linear trend was - 2.7% in diabetic patients compared to controls (p = 0.009) In addition, the PVD of the DCP and the intermediate capillary plexus (ICP) were evaluated separately. Regarding the DCP PVD, no statistically significant difference at any time points in diabetic patients compared to controls and no statistically significant difference in the linear trend was found (p > 0.1). Conversely, no difference was recorded for parafoveal ICP density at individual time points (p > 0.1), but a statistically significant difference in the linear trend over time in diabetic patients compared to controls was recoded (- 3.2% per year, p = 0.001). Despite the apparent intergroup differences at baseline in structural OCT parameters, the differences including ILM-IPL (p = 0.273), IPL-INL (p = 0.708), and IPL-ONL (p = 0.054) were modest and not statistically significant with time. Therefore, the microvascular change of the deeper vessels might be a robust biomarker to evaluate the clinical progression of DR in DM1.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-020-75416-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7589477PMC
October 2020

Early Alterations of Corneal Subbasal Plexus in Uncomplicated Type 1 Diabetes Patients.

J Ophthalmol 2019 2;2019:9818217. Epub 2019 Jul 2.

Unit of Endocrinology, Diabetes and Metabolism, S. Giovanni Calibita Fatebenefratelli Hospital, Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy.

Purpose: The purpose of our study is to describe the in vivo corneal confocal microscopy characteristics of subbasal nerve plexus in a highly selected population of patients affected by type 1 diabetes mellitus (T1DM) without any microvascular diabetes complications.

Methods: We included 19 T1DM patients without diabetic peripheral neuropathy, diabetic autonomic neuropathy, diabetic retinopathy, and microalbuminuria. All patients underwent in vivo corneal confocal microscopy and blood analysis to determine subbasal nerve plexus parameters and their correlation with clinical data. We compared the results with 19 healthy controls.

Results: The T1DM group showed a significant decrease of the nerve fiber length (=0.032), the nerve fiber length density (=0.034), the number of fibers (=0.005), and the number of branchings (=0.028), compared to healthy subjects. The nerve fiber length, nerve fiber length density, and number of fibers were directly related to the age at onset of diabetes and inversely to the duration of DM. BMI (body mass index) was highly related to the nerve fiber length ( = -0.6, =0.007), to the nerve fiber length density ( = -0.6, =0.007), and to the number of fibers ( = -0.587, =0.008). No significant correlations were found between the corneal parameters and HbA1c.

Conclusions: Early subclinical fiber corneal variation could be easily detected using in vivo corneal confocal microscopy, even in type 1 diabetes without any microvascular diabetes complications, including diabetic peripheral neuropathy, diabetic autonomic neuropathy, diabetic retinopathy, and microalbuminuria.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1155/2019/9818217DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6636466PMC
July 2019

Activation of retinal Müller cells in response to glucose variability.

Endocrine 2019 09 20;65(3):542-549. Epub 2019 Jul 20.

Department of Experimental Medicine, University of Rome Tor Vergata, Rome, Italy.

Purpose: In the earliest stages of diabetic retinopathy (DR), a dysfunction of Müller cells, characterized by high levels of glial fibrillary acidic protein (GFAP), and aquaporins (AQP), has been observed. Although chronic hyperglycemia causes the activation of Müller cells, the effect of glycemic fluctuations is yet unknown. The aim of the study was to analyze the impact of glucose variability on rat retinal Müller cells (rMC-1) adapted to either normal (5 mM) or high (25 mM) glucose levels.

Methods: rMC-1 were cultured in a medium containing either 5 mM (N cells) or 25 mM of glucose (H cells) and then incubated for 96 h in a medium containing (a) low glucose (either 1-3 or 5 mM), (b) basal glucose (either 5 or 25 mM), (c) high glucose (either 25 or 45 mM), (d) basal and high glucose alternated every 24 h; (e) low- and high glucose alternated every 24 h; (f) basal glucose with episodes of low glucose for 30 min twice a day. Müller cells activation was evaluated by measuring the levels of GFAP, AQP4, and phospho-active extracellular signal-regulated kinase (pERK).

Results: Under both basal and high glucose concentrations rMC-1 were viable, but their response to glucose excursions was different. In N cells kept under normal (5 mM) glucose, a significant glial activation was measured not only in response to constant high glucose but also to alternating low/high glucose. In H cells, adapted to 25 mM glucose, a significant response was observed only after exposition to a lower (5 mM) glucose concentration.

Conclusion: Our results highlight Müller cells activation in response to glucose variability and a different susceptibility depending on the basal glucose conditions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12020-019-02017-5DOI Listing
September 2019

Flavonoids and Insulin-Resistance: From Molecular Evidences to Clinical Trials.

Int J Mol Sci 2019 Apr 26;20(9). Epub 2019 Apr 26.

Unit of Endocrinology, Diabetes and Metabolism, S.Giovanni Calibita, Fatebenefratelli Hospital, 00186 Rome, Italy.

Insulin-resistance is one of the main factors responsible for the onset and progression of Metabolic Syndrome (MetS). Among all polyphenols, the effects of flavonoids and their main food sources on insulin sensitivity have been widely evaluated in molecular and clinical studies. The aim of this review is to analyse the data observed in vitro, in vivo and in clinical trials concerning the effects of flavonoids on insulin resistance and to determine the molecular mechanisms with which flavonoids interact with insulin signaling.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms20092061DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6539502PMC
April 2019

Ten years of experience with DPP-4 inhibitors for the treatment of type 2 diabetes mellitus.

Acta Diabetol 2019 Jun 2;56(6):605-617. Epub 2019 Jan 2.

Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy.

Achieving and maintaining recommended glycemic targets without causing adverse e ffects, including hypoglycemia, is challenging, especially in older patients with type 2 diabetes mellitus (T2DM). The introduction of dipeptidyl peptidase-4 (DPP-4) inhibitors, more than 10 years ago, has provided an alternative to conventional medications for the intensification of glucose-lowering treatment after failure of metformin monotherapy, and therefore, marked an important advance in the management of T2DM. By prolonging the activity of incretin hormones, DPP-4 inhibitors induce insulin release and decrease glucagon secretion in a glucose-dependent manner. This results in a more physiologic glycemic control as compared to that ensured by insulin secretagogues (sulfonylureas and glinides). Overall, DPP-4 inhibitors have a favorable safety profile and can be used without dose adjustments in older adults and in patients with mild renal impairment; they have a neutral effect on body weight and do not cause hypoglycemia by themselves. Safety issues, reported mainly in post-marketing surveillance programs and including cardiovascular outcomes and the risk of acute pancreatitis, are being extensively investigated. The aim of this review is to discuss the impact of DPP-4 inhibitors on the treatment of T2DM, after 10 years of experience, with an emphasis on diabetes care in Italy. We will first describe T2DM treatment in Italy and then provide an overview of the main findings from randomized controlled trials, real-world studies and post-marketing surveillance programs with DPP-4 inhibitors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00592-018-1271-3DOI Listing
June 2019

Association between Early Neuroretinal Dysfunction and Peripheral Motor Unit Loss in Patients with Type 1 Diabetes Mellitus.

J Diabetes Res 2018 4;2018:9763507. Epub 2018 Oct 4.

Unit of Endocrinology, Diabetes and Metabolism, S. Giovanni Calibita Fatebenefratelli Hospital, Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy.

Objectives: It has been already confirmed that retinal neurodegeneration has a predictive value in the development of microvascular alterations in diabetic retinopathy. However, no data are available on the association between neuroretinal dysfunction and peripheral motor unit loss. Our study, therefore, was aimed at investigating the hypothesis that retinal neurodegeneration could be considered an early marker of diabetic peripheral neuropathy (DPN).

Methods: 20 T1DM patients with no symptoms/signs of peripheral polyneuropathy, without DR or with very mild nonproliferative DR, and 14 healthy controls (C) age- and gender-matched were enrolled. The following electrophysiological tests were performed: standard nerve conduction studies (NCS) and incremental motor unit number estimation (MUNE) from the abductor hallux (AH) and abductor digiti minimi (ADM). Neuroretinal function was studied by multifocal electroretinogram (MfERG) recordings, measuring response amplitude density (RAD) and implicit time (IT) from rings and sectors of superior (S)/inferior (I)/temporal (T)/nasal (N) macular sectors up to 10 degrees of foveal eccentricity.

Results: MfERG RADs from rings and sectors were significantly reduced in T1DM ( < 0.05) vs. C. ADM MUNE and AH MUNE were significantly decreased in T1DM ( = 0.039 and < 0.0001, respectively) vs. C. A positive correlation between mean MfERG RADs from the central 5 degrees of the four (S, I, T, and N) macular sectors and lower limb motor unit number ( = 0.50, = 0.041; = 0.64, = 0.005; = 0.64, = 0.006; and = 0.61, = 0.010, respectively) was observed in T1DM patients. No abnormalities of NCS were found in any subject.

Conclusions: The motor unit loss on the one hand and neuroretinal dysfunction on the other hand are already present in T1DM patients without DPN. The relationship between neuroretinal dysfunction and motor unit decline supports the hypothesis that neuroretina may represent a potential "window" to track the early neurogenic damage in diabetes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1155/2018/9763507DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6193343PMC
January 2019

Early and localized retinal dysfunction in patients with type 1 diabetes mellitus studied by multifocal electroretinogram.

Acta Diabetol 2018 Nov 28;55(11):1191-1200. Epub 2018 Aug 28.

IRCCS-Fondazione Bietti, Via Livenza 1, 00198, Rome, Italy.

Aims: To investigate the function of localized retinal areas in highly selected type 1 diabetes mellitus patients (DM1) with no or mild signs of diabetic retinopathy (NO DR and NPDR, respectively) and its correlation with age, diabetes duration and glycemic control.

Methods: Multifocal electroretinograms (mfERG) were recorded in 35 eyes of 18 NO DR patients and 38 eyes of 19 NPDR patients. Thirty-one eyes of 17 normal subjects were enrolled as controls. N1-P1 response amplitude densities (RADs) and P1 implicit times (ITs) from isolated (R1: 0°-2.5°, R2: 2.5°-5°, R3: 5°-10°) and combined (R1 + R2, R2 + R3 and R1 + R2 + R3) annular rings and from four retinal sectors (nasal, N; temporal, T; superior, S and inferior, I) with increasing eccentricities up to 10° (S1, S2, S3, S1 + S2, S1 + S2 + S3) were measured. The statistical differences between DM1 groups and controls were tested by ANOVA. The electrophysiological data were correlated with age, duration of diabetes and glycated hemoglobin (HbA1c) level using the Pearson's test.

Results: MfERG RADs, but not ITs, from all isolated and combined rings and sectors up to 10° of foveal eccentricity were statistically different between DM1 groups compared to controls. No significant differences were found between NO DR and NPDR patients. The mfERG abnormalities of the central retinal areas were correlated significantly with age in both DM1 groups and with diabetes duration mainly in NPDR group.

Conclusions: In DM1 patients, localized retinal dysfunction, described by reduced mfERG RAD, can be observed also in the absence of clinical signs of DR and it is related to aging.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00592-018-1209-9DOI Listing
November 2018

Effect of the GSTM1 gene deletion on glycemic variability, sympatho-vagal balance and arterial stiffness in patients with metabolic syndrome, but without diabetes.

Diabetes Res Clin Pract 2018 Apr 13;138:158-168. Epub 2018 Feb 13.

Endocrinology, Diabetes and Metabolism, S. Giovanni Calibita Fatebenefratelli Hospital, Dept. of Systems Medicine, University of Rome Tor Vergata, Rome, Italy. Electronic address:

Aims: An increased rate of cerebrovascular complications in patients with metabolic syndrome (MetS) has been reported. Previous studies demonstrated an association between glycemic variability (GV) and cerebrovascular reactivity (CRV) in MetS, thus suggesting a putative role of GV on cerebrovascular events. Although the pathophysiological mechanism linking GV to damage is still to be elucidated, evidence suggests oxidative stress plays a crucial role. Since functional variants in glutathione S-transferases (GST) genes modulate the cellular detoxification processes, the aim of this study was to elucidate the involvement of GSTs in MetS and investigating the correlation with GV, arterial stiffness, and sympatho-vagal (SV) balance.

Methods: A hundred metabolic syndrome patients without diabetes underwent GST gene polymorphism analysis and a sub-sample 36 patients were randomly selected to investigate the correlation between GST gene polymorphisms and GV, and sympatho-vagal (SV) balance and arterial stiffness.

Results: GSTM1 showed a significant association with several GV, arterial stiffness, and SV balance indexes. In particular, the GSTM1 deletion positively correlates with lower values of these indexes when compared to the presence of the gene.

Conclusions: Therefore, we suggested a global influence of GSTM1 deletion on the GV, arterial stiffness, and SV balance pathways in MetS patients, probably also interacting with AMP-activated protein kinase (AMPK) regulation. Our novel findings indicate GSTM1 could be a risk locus in MetS development and shed light novel scenarios on the role of glucose fluctuations in neurological impairments.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.diabres.2018.02.006DOI Listing
April 2018

Single Retinal Layer Evaluation in Patients with Type 1 Diabetes with No or Early Signs of Diabetic Retinopathy: The First Hint of Neurovascular Crosstalk Damage between Neurons and Capillaries?

Ophthalmologica 2017 8;237(4):223-231. Epub 2017 Apr 8.

Department of Ophthalmology, G.B. Bietti Eye Foundation-IRCCS, Rome, Italy.

Purpose: To analyze the retinal-choroidal changes in type 1 diabetes mellitus (DM1) patients with no or early signs of diabetic retinopathy (DR).

Methods: Seventy-six eyes of 38 DM1 patients and 26 control eyes were included. Nine individual retinal layer thickness measurements were obtained using the spectral domain-optical coherence tomography automated segmentation algorithm.

Results: The retinal nerve fiber layer was slightly thinner in all explored quadrants, even if the reduction was not significant in DM1 eyes versus control eyes. The inner nuclear layer (INL) thickness was thicker in all DM1 eyes versus control eyes in all quadrants (p < 0.050). Analyses adjusting for inner retinal thickness in all sectors confirmed INL thickening by about 4%, and also found a significant thinning of the ganglion cell layer (GCL) by about 3.5% in all DM1 subjects versus controls (p < 0.050).

Conclusion: DM1 patients with no or early signs of DR present retinal changes particularly at the INL and GCL that might be correlated to initial findings of neurodegeneration.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000453551DOI Listing
September 2017

Retinal neurodegeneration in patients with type 1 diabetes mellitus: the role of glycemic variability.

Acta Diabetol 2017 May 25;54(5):489-497. Epub 2017 Feb 25.

Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy.

Aims: Recent studies have identified neuroretinal abnormalities in persons affected by diabetes mellitus, before the onset of microvascular alterations. However, the role of glycemic variability (GV) on early retinal neurodegeneration is still not clarified.

Methods: To explore the relationship between glycemic control and neuroretinal characteristics, 37 persons with Type 1 diabetes mellitus (Type 1 DM) divided into two groups with no signs (noRD) and with mild non-proliferative diabetic retinopathy (NPDR) compared to 13 healthy control participants (C) were recruited. All persons underwent an optical coherence tomography with automatic segmentation of all neuroretinal layers. Measurements of mean of nasal (N)/temporal (T)/superior (S)/inferior (I) macular quadrants for individual layer were also calculated. Metabolic control was evaluated by glycated hemoglobin (HbA1c), and indexes of GV were calculated from continuous glucose monitoring.

Results: The difference among the three groups in terms of RNFL thickness was significantly dependent on quadrant (F(6;132) = 2.315; p = 0.037). This interaction was due to a specific difference in RNFL-N thickness, where both Type 1 DM groups showed a similar reduction versus C (-3.9 for noDR and -4.9 for NPDR), without any relevant difference between them (-1.0). Inner nuclear layer (INL) was increased in all quadrants in the two Type 1 DM groups compared to C (mean difference = 7.73; 95% CI: 0.32-15.14, p = 0.043; mean difference = 7.74; 95% CI: 0.33-15.15, p = 0.043, respectively). A negative correlation between RNFL-N and low blood glucose index (r = -0.382, p = 0.034) and positive correlation between INL and continuous overall net glycemic action -1, -2, -4 h (r = 0.40, p = 0.025; r = 0.39, p = 0.031; r = 0.41, p = 0.021, respectively) were observed in Type 1 DM patients. The triglycerides were positively and significantly correlated to INL (r = 0.48, p = 0.011), in Type 1 DM subjects. GV and triglycerides resulted both independent predictors of increased INL thickness. No correlation was found with HbA1c.

Conclusions: Early structural damage of neuroretina in persons with Type 1 DM patients is related to glucose fluctuations. GV should be addressed, even in the presence of a good metabolic control.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00592-017-0971-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5385321PMC
May 2017

Early microvascular retinal changes in optical coherence tomography angiography in patients with type 1 diabetes mellitus.

Acta Ophthalmol 2017 Dec 16;95(8):e751-e755. Epub 2017 Feb 16.

Fondazione G.B.Bietti-IRCCS, Rome, Italy.

Purpose: Diabetic retinopathy (DR) can lead to significant vision loss and blindness and has a particularly high prevalence in patients with type 1 diabetes (DM1). In this study, we investigate quantitative differences in optical coherence tomography angiography (OCTA) data between DM1 patients with no or mild signs of retinopathy and non-diabetic subjects.

Methods: Optical coherence tomography angiography (OCTA) imaging was performed on DM1 patients with no or mild nonproliferative diabetic retinopathy and healthy, age-matched controls. Parafoveal vessel density and foveal avascular zone (FAZ) area in the deep capillary plexus (DCP) and superficial capillary plexus (SCP) were calculated with automated quantification software and compared between patient cohorts.

Results: A significant decrease in parafoveal vessel density was seen in the DCP of DM1 patients compared to non-diabetic controls (57.0 ± 3.3% versus 60.7 ± 2.4%, p < 0.001). There was no significant difference in SCP parafoveal vessel density, DCP FAZ area, or SCP FAZ area between cohorts.

Conclusion: M1 patients with no or mild signs of retinopathy have reduced parafoveal vessel density in the DCP on OCTA when compared to non-diabetic controls. These OCTA findings suggest that parafoveal capillary nonperfusion is an early process in DM1-related retinal changes and occurs initially at the level of the DCP. Further investigation is needed to understand the prognostic role of these vascular changes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/aos.13404DOI Listing
December 2017

Acute hyperglycemia reduces cerebrovascular reactivity: the role of glycemic variability.

J Clin Endocrinol Metab 2014 Aug 30;99(8):2854-60. Epub 2014 May 30.

Unit of Endocrinology, Diabetes, and Metabolism (I.G., A.D.F., F.P., I.M., D.Y., S.F.); Department of Neurology (P.Pal., F.P.); and Fatebenefratelli Association for Research Unit of Internal Medicine (S.D., P.Pas.) and Service of Medical Statistics and Information Technology (S.D., P.Pas.), S. Giovanni Calibita Fatebenefratelli Hospital, 00186 Rome, Italy; Department of Systems Medicine (I.G., A.D.F., F.P., I.M., D.Y., D.L., S.F.), University of Rome Tor Vergata, 00133 Rome, Italy; Department of Neurology (P.Pal., R.A., F.V.), Campus Bio-Medico University, 00128 Rome, Italy; and Unit of Health Management (S.D.), Ministry of Health, Viale Giorgio Ribotta 5, 00144 Rome, Italy.

Context: Cerebral vasomotor reactivity (CVR) is reduced in patients with diabetes mellitus (DM), and glucose variability (GV) might be responsible for cerebrovascular damage.

Objective: Studying patients with insulin resistance without DM, we explored the role of GV in impairing CVR.

Patients: We studied 18 metabolic syndrome (MS) patients without DM, 9 controls (C), and 26 patients with DM.

Main Outcome Measures: Groups were compared in terms of CVR, GV, and 24-hour blood pressure. To evaluate the impact of acute hyperglycemia on CVR, a hyperglycemic clamp was performed in MS patients and controls.

Results: Baseline CVR was reduced in DM vs C and MS (C vs DM = 20.2, 95% CI = 3.5-36.9, P = .014; and MS vs DM = 22.2, 95% CI = 8.6-35.8, P = .001), but similar between MS and C (MS vs C = 2.0, 95% CI = -14.7 to 18.7, P = .643). During acute hyperglycemia, CVR fell in MS and C to values comparable to DM. GV progressively increased from C to MS to DM. In MS, CVR at 120 minutes and GV displayed a negative correlation (r = -0.48, P = .043), which did not change after controlling for mean 24-hour systolic and diastolic blood pressure. In MS, the CVR reduction was significantly correlated to GV (r = 0.55, P = .02).

Conclusions: GV is increased in patients with MS but without DM and is the major predictor of CVR reduction induced by acute hyperglycemia, possibly representing the earliest cause of cerebrovascular damage in DM.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1210/jc.2014-1087DOI Listing
August 2014

Cerebral hemodynamics and systemic endothelial function are already impaired in well-controlled type 2 diabetic patients, with short-term disease.

PLoS One 2013 31;8(12):e83287. Epub 2013 Dec 31.

Endocrinology, Diabetes and Metabolism, S. Giovanni Calibita Fatebenefratelli Hospital, University of Rome Tor Vergata, Rome, Italy.

Objective: Impaired cerebral vasomotor reactivity (VMR) and flow-mediated dilation (FMD) were found in selected subgroups of type 2 diabetes mellitus (T2DM) patients with long-term disease. Our study aimed to evaluate cerebral hemodynamics, systemic endothelial function and sympatho-vagal balance in a selected population of well-controlled T2DM patients with short-term disease and without cardiac autonomic neuropathy (CAN).

Research Design And Methods: Twenty-six T2DM patients with short-term (4.40±4.80 years) and well-controlled (HbA1C = 6.71±1.29%) disease, without any complications, treated with diet and/or metformin, were consecutively recruited. Eighteen controls, comparable by sex and age, were enrolled also.

Results: FMD and shear rate FMD were found to be reduced in T2DM subjects with short-term disease (8.5% SD 3.5 and 2.5 SD 1.3, respectively) compared to controls (15.4% SD 4.1 and 3.5 SD 1.4; p<.001 and p<.05). T2DM patients also displayed reduced VMR values than controls (39.4% SD 12.4 vs 51.7%, SD 15.5; p<.05). Sympatho-vagal balance was not different in T2DM patients compared to healthy subjects. FMD and shear rate FMD did not correlate with VMR in T2DM patients or in controls (p>.05).

Conclusions: In well-controlled T2DM patients with short-term disease cerebral hemodynamics and systemic endothelial function are altered while autonomic balance appeared to be preserved.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0083287PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3877017PMC
August 2014

Preliminary evidence that obese patients with obstructive sleep apnea/hypopnea syndrome are refractory to the acute beneficial metabolic effects of a very low calorie diet.

Acta Diabetol 2013 Aug 6;50(4):639-43. Epub 2013 Jun 6.

Department of Medicina dei Sistemi, University of Rome Tor Vergata, Rome, Italy.

Since obesity seems to play a causal role in both obstructive sleep apnea/hypopnea syndrome (OSAHS) and type 2 diabetes, the question arises whether diet-induced weight loss is equally efficacious in type 2 diabetic patients with and without OSAHS. The present study was aimed to investigate the effect of 1 week very low calorie diet (VLCD) on oxygen desaturation index (ODI) and on glucose regulation in OSAHS versus non-OSAHS patients. Fourteen patients with type 2 diabetes mellitus and morbid obesity were enrolled. According to ODI, patients were divided into 2 groups (with and without OSAHS) and evaluated by a hyperglycemic clamp study, before and after a 7 day-VLCD. After a VLCD, a significant reduction of anthropometric parameters, in the overall group and in subgroups, was observed. M-value and acute insulin response increased significantly only in patients without obstructive sleep apnea (990.10 ± 170.19 vs. 1,205.22 ± 145.73 μmol min(-1) m(-2), p = 0.046; -1.05 ± 8.40 vs. 48.26 ± 11. 90 pmol/L, p = 0.028, respectively). The average 24-h heart rate (24-h HR) fell significantly (p = 0.05), primarily because of a decrease during daytime (p = 0.041), in the whole group. In conclusion, we observed that morbidly obese patients with type 2 diabetes and OSAHS are specifically resistant to the acute beneficial effects of VLCD on metabolic parameters. Our preliminary observation deserves further investigation to clarify the pathogenetic mechanisms involved.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00592-013-0487-5DOI Listing
August 2013

Very-low-calorie diet: a quick therapeutic tool to improve β cell function in morbidly obese patients with type 2 diabetes.

Am J Clin Nutr 2012 Mar 8;95(3):609-13. Epub 2012 Feb 8.

Department of Medicine, University of Rome Tor Vergata, Rome, Italy.

Background: Caloric restriction in obese diabetic patients quickly improves glucose control, independently from weight loss. However, the early effects of a very-low-calorie diet (VLCD) on insulin sensitivity and insulin secretion in morbidly obese patients with type 2 diabetes are still unclear.

Objective: The objective was to study the relative contributions of insulin sensitivity, insulin secretion, or both to improvement in glucose metabolism, after 1 wk of caloric restriction, in severely obese diabetic patients.

Design: Hyperglycemic clamps were performed in 14 severely obese (BMI, in kg/m(2): >40) patients with type 2 diabetes in good glucose control (glycated hemoglobin < 7.5%) before and after 7 d of a VLCD (400 kcal/d).

Results: The VLCD caused a 3.22 ± 0.56% weight loss (P < 0.001), 42.0% of which was fat loss, accompanied by decreases in fasting plasma glucose (P < 0.05) and triglycerides (P < 0.01). In parallel, the Disposition Index, which measures the body's capability to dispose of a glucose load, increased from 59.0 ± 6.3 to 75.5 ± 6.3 mL· min(-1) · m(-2) body surface area (P < 0.01), because of improvements in indexes of both first- and second-phase insulin secretion (P < 0.02), but with no changes in insulin sensitivity (P = 0.33).

Conclusion: The marked improvement in metabolic profile, observed in severely obese patients with type 2 diabetes after a 7-d VLCD, was primarily due to the amelioration of β cell function, whereas no contribution of insulin sensitivity was shown. This trial was registered at www.clinicaltrials.gov as NCT01447524.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3945/ajcn.111.023697DOI Listing
March 2012

Impact of glycemic and blood pressure variability on surrogate measures of cardiovascular outcomes in type 2 diabetic patients.

Diabetes Care 2011 Jul 24;34(7):1605-9. Epub 2011 May 24.

Endocrinology, Diabetes and Metabolism, S. Giovanni Calibita Fatebenefratelli Hospital, University of Rome Tor Vergata, Rome, Italy.

Objective: The effect of glycemic variability (GV) on cardiovascular risk has not been fully clarified in type 2 diabetes. We evaluated the effect of GV, blood pressure (BP), and oxidative stress on intima-media thickness (IMT), left ventricular mass index (LVMI), flow-mediated dilation (FMD), and sympathovagal balance (low frequency [LF]/high frequency [HF] ratio) in 26 type 2 diabetic patients (diabetes duration 4.41±4.81 years; HbA1c 6.70±1.25%) receiving diet and/or metformin treatment, with no hypotensive treatment or complications.

Research Design And Methods: Continuous glucose monitoring (CGM) data were used to calculate mean amplitude of glycemic excursion (MAGE), continuous overall net glycemic action (CONGA)-2, mean blood glucose (MBG), mean postprandial glucose excursion (MPPGE), and incremental area under the curve (IAUC). Blood pressure (BP), circadian rhythm, and urinary 15-F2t-isoprostane (8-iso-prostaglandin F2α [PGF2α]) were also evaluated. Subjects were divided into dipper (D) and nondipper (ND) groups according to ΔBP.

Results: IMT and LVMI were increased in ND versus D (0.77±0.08 vs. 0.68±0.13 [P=0.04] and 67±14 vs. 55±11 [P=0.03], respectively). MBG, MAGE, and IAUC were significantly associated with LF/HF ratio at night (r=0.50, P=0.01; r=0.40, P=0.04; r=0.41, P=0.04, respectively), MPPGE was negatively associated with FMD (r=-0.45, P=0.02), and CONGA-2 was positively associated with LVMI (r=0.55, P=0.006). The Δsystolic BP was negatively associated with IMT (r=-0.43, P=0.03) and with LVMI (r=-0.52, P=0.01). Urinary 8-iso-PGF2α was positively associated with LVMI (r=0.68 P<0.001).

Conclusions: An impaired GV and BP variability is associated with endothelial and cardiovascular damage in short-term diabetic patients with optimal metabolic control. Oxidative stress is the only independent predictor of increased LV mass and correlates with glucose and BP variability.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2337/dc11-0034DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3120198PMC
July 2011