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M Massi Benedetti

Publications and source records attributed to M Massi Benedetti.

16 recordsLinked to original sources
PubMed2006

Early detection of insulin deprivation in continuous subcutaneous insulin infusion-treated patients with type 1 diabetes.

BACKGROUND: This study was performed to define the clinical relevance of early changes of capillary 3beta-hydroxybutyrate (3betaOHB), for detection of metabolic deterioration before occurrence of overt diabetic ketoacidosis following interruption of continuous subcutaneous insulin infusion (CSII). METHODS: An open clinical trial was performed with eight patients with type 1 diabetes on CSII therapy. After an overnight fast, at 8 a.m. (T0) CSII was interrupted for 4 h. At noon (T240) CSII was re-established, and at 4 p.m. (T480) the study was ended. Blood glucose (BG) and capillary and plasma 3betaOHB were measured at 30-min intervals, plasma insulin at 60-min intervals, and urinary ketones at 120-min intervals. RESULTS: After CSII interruption mean BG increased from 149.8+/-54.4 mg/dL at T0 to 224.8+/-56.2 mg/dL at T240 (P<0.05), and mean capillary 3betaOHB increased from 0.1+/-0.1 mmol/L at T0 to 0.9+/-0.6 mmol/L at T240 (P<0.001). The rate of increase of capillary 3betaOHB was faster and significantly more relevant than that of BG (P<0.05). The restoration of CSII produced a significant reduction of mean BG and capillary 3betaOHB (T480, 119.5+/-24 mg/dL and 0.2+/-0.2 mmol/L, respectively; P<0.05 for both vs. T240). The recovery of capillary 3betaOHB was significantly faster than that of BG (P=0.03). CONCLUSIONS: The dynamic evaluation of changes of capillary 3betaOHB levels can represent a useful support to home BG monitoring in the event of CSII interruption, providing faster information on early metabolic deterioration due to insulin deprivation and allowing preventative action for avoiding the evolution towards overt diabetic ketoacidosis. After reintroduction of insulin infusion the monitoring of the faster recovery of 3betaOHB relative to BG can provide useful information for the prevention of late hypoglycemia due to insulin overinfusion.

3-Hydroxybutyric Acid↗
PubMed2006

Model based study on monitoring ketone bodies to improve safety in intensive insulin therapy.

AIM: The present study explores new signals (capillary 3betahydroxybutyrate - 3betaOHB) for improving the safety of a closed loop insulin infusion system (external wearable artificial pancreas). METHODS: Data collected during a clinical trial on diabetic subjects including a period of insulin deprivation were interpreted through mathematical models to simulate the effect of monitoring ketone bodies (capillary 3betaOHB, KB) compared to blood glucose in subjects on Continuous Subcutaneous Insulin Infusion (CSII) treatment. RESULTS: The estimation of model coefficients satisfactorily fits experimental data. The evaluation of dynamic changes of capillary 3betaOHB levels showed a more rapid response than blood glucose. CONCLUSIONS: The effect of the combination of monitoring of glucose and ketone bodies can consistently improve the safety and efficacy of the use of a closed loop system for glycemic control in dangerous situations like ketoacidosis. If a subcutaneous glucose-ketone bodies sensor were to become available in the near future it would be a key component of an external artificial pancreas.

3-Hydroxybutyric Acid↗
PubMed2003

A one-year, randomised, multicentre trial comparing insulin glargine with NPH insulin in combination with oral agents in patients with type 2 diabetes.

AIMS: The aim of the trial was to compare the efficacy and safety of the new, long-acting basal insulin, insulin glargine (LANTUS(R)), with NPH human insulin, each administered in a combination regimen with oral antidiabetic drugs in patients with Type 2 diabetes. METHODS: In a multicentre, open, randomised study, 570 patients with Type 2 diabetes, aged 34 - 80 years, were treated for 52 weeks with insulin glargine or NPH insulin given once daily at bedtime. Previous oral antidiabetic therapy was continued throughout the study. RESULTS: There was a clinically relevant decrease in glycosylated haemoglobin (GHb) values from baseline to endpoint with both drugs (insulin glargine: - 0.46 %; NPH insulin: - 0.38 %; p = 0.415); also, this difference was statistically significant in the subgroup of overweight patients with BMI > 28 kg/m 2 (insulin glargine: - 0.42 %, NPH insulin: - 0.11 %; p = 0.0237). Over the entire treatment period, NPH insulin-treated patients (41 %) and insulin glargine-treated patients (35 %) experienced a similar level of symptomatic hypoglycaemia. A statistically significant difference was observed in the number of patients treated with NPH insulin who reported at least one episode of nocturnal hypoglycaemia compared with those treated with insulin glargine in the overall population and in the overweight subgroup (overall: 24 % vs. 12 %, p = 0.002; overweight: 22.2 % vs. 9.5 %, p = 0.0006), using the Cochran-Mantel-Haenszel test. These differences were most pronounced in insulin-naïve and overweight (BMI > 28 kg/m 2) sub-groups. The incidence of adverse events was similar for the two treatments. CONCLUSIONS: This study demonstrated that insulin glargine is as effective as NPH insulin in achieving glycaemic control in patients with Type 2 diabetes, and is associated with fewer episodes of symptomatic hypoglycaemia, particularly nocturnal episodes.

Adult↗
PubMed2001

The relationship between physicians' self-reported target fasting blood glucose levels and metabolic control in type 2 diabetes. The QuED Study Group--quality of care and outcomes in type 2 diabetes.

OBJECTIVE: To investigate the relationship between beliefs of physicians relative to intensive metabolic control in type 2 diabetes and levels of HbA1c obtained in a sample of their patients. RESEARCH DESIGN AND METHODS: Physicians' beliefs were investigated through a questionnaire sent to a sample of self-selected clinicians participating in a nationwide initiative aimed at assessing the relationship between the quality of care delivered to patients with type 2 diabetes and their outcomes. At the same time, physicians were asked to collect clinical data on a random sample of their patients, stratified by age (<65 vs. > or = 65 years). Mean HbA1c levels in the study population were thus evaluated according to target fasting blood glucose (FBG) used by their physicians. RESULTS: Of 456 physicians, 342 (75%) returned the questionnaire. Among the responders, 200 diabetologists and 99 general practitioners (GPs) recruited 3,297 patients; 2,003 of whom were always followed by the same physician and 1,294 of whom were seen by different physicians in the same structure on different occasions. Only 14% of the respondents used target FBG levels < or = 6.1 mmol/l, whereas 38% pursued values >7.8 mmol/l, with no statistically significant difference between diabetologists and GPs. The analysis of the relationship between FBG targets and metabolic control, restricted to those patients always seen by the same physician, showed a strong linear association, with mean HbA1c values of 7.0 +/- 1.6 for patients in the charge of physicians pursuing FBG levels < or = 6.1 mmol/l and 7.8 +/- 1.8 for those followed by physicians who used target values >7.8 mmol/l. After adjusting for patients' and physicians' characteristics, the risk of having HbA1c values > 7.0% was highly correlated with physicians' beliefs. Patients followed by different physicians in the same unit showed a risk of inadequate metabolic control similar to that of patients followed by physicians adopting a nonaggressive policy. CONCLUSIONS: Doctors adopt extremely heterogeneous target FBG levels in patients with type 2 diabetes, which in turn represent an important independent predictor of metabolic control. To improve patient outcomes, physicians-centered educational activities aimed at increasing the awareness of the potential benefits of a tight metabolic control in patients with type 2 diabetes are urgently needed.

Aged↗
PubMed1997

Patterns of care an Italian diabetic population. The Italian Study Group for the Implementation of the St Vincent Declaration, Società Italiana di Diabetologia, Associazione Medici Diabetologi.

We set out to describe patterns of care of an Italian diabetic population, with reference to the recommendations of the St Vincent Declaration. We investigated different aspects of care received by 2707 patients, of whom 2196 in the charge of 35 Diabetes Outpatient Clinics (DOCs) and 511 cared for by 49 General Practitioners (GPs). Data were collected by interviewing the patients, their physicians and by reviewing medical records. Our data show that diabetes care in Italy differs in many aspects from the recommendations of the St Vincent Declaration. Glycated haemoglobin measurement was lacking in 50% of the patients in the charge of GPs and in 15% of those attending DOCs. While the control of cardiovascular risk factors was satisfactory, information on albumin excretion was not available in one third of the patients. Overall, 79% of the patients had had an eye examination in the previous 12 months. More than one-third of the patients had not received adequate information on different aspects of care, with wide variations according to the setting of care. Forty-two per cent of the patients attending DOCs and 14% of those cared for by GPs practised blood glucose self-monitoring; similarly, insulin therapy self-management was performed by 50% and 19% of the patients attending DOCs and GPs, respectively. Our data call for vigorous efforts aimed at improving the awareness of the potential for reducing major diabetic complications. Therefore, it is essential to promote the incorporation of clearly defined clinical practice guidelines at each level of care.

Aged↗
PubMed1996

Epidemiology and determinants of blood glucose self-monitoring in clinical practice.

The aim of this study was to describe the epidemiology of self-monitoring of blood glucose and to identify specific characteristics of those subgroups of diabetic patients treated with insulin that are most likely to monitor their blood glucose according to medical recommendations. Data were collected on 1384 insulin-treated patients, enrolled from 35 diabetic outpatient clinics and 49 general practitioners' offices between December 1993 and June 1994. Seventeen Italian regions out of 20 were included in the study. Our data show that 418 (31%) diabetic patients treated with insulin had never practised blood glucose self-monitoring. In addition, only 242 patients (18.2%) self-monitored their glycemia with a mean frequency of at least once a day (29.7% among insulin-dependent diabetes mellitus (IDDM) and 13.9%, among insulin-treated non-insulin-dependent diabetes mellitus (NIDDM-IT) patients). Patients' characteristics associated with a higher probability of practising blood glucose self-monitoring were age below 50 years, being treated at a diabetic outpatient clinic, hypertension, need of three or more insulin injections per day, history of hypoglycemic episodes, ability to self-manage insulin doses. Our study calls for vigorous efforts aimed at promoting the incorporation of clearly-defined educational programs at each level of care, in order to improve the motivation and self-care of diabetic patients. Furthermore, studies are necessary to identify subgroups of diabetic patients that truly need to self-monitor blood glycemia, and to assess the efficacy of the practice of self-monitoring of blood glucose in improving metabolic control and reducing acute and long-term diabetic complications.

Aged↗
PubMed1991

Time delay compensation for closed-loop insulin delivery systems: a simulation study.

Closed loop insulin therapy certainly represents the best possible approach to insulin replacement. However, present limitations preclude wider application of the so-called artificial pancreas. Therefore, a thorough understanding of these limitations is needed to design better systems for future long-term use. The present simulation study was design: to obtain better information on the impact of the measurement delay of currently available closed-loop devices both during closed-loop insulin delivery and blood glucose clamp studies, and to design and test a time delay compensator based on the method originally described by O.J. Smith. Simulations were performed on a Compaq Deskpro 486/25 personal computer under MS-DOS operating system using Simnon rel. 3.00 software. There was a direct relationship between measurement delay and amount of insulin delivered, i.e., the longer the delay the higher the insulin dose needed to control a rise in blood glucose; the closed-loop response in presence of a time delay was qualitatively impaired both during insulin delivery and blood glucose clamp studies; time delay compensation was effective in reducing the insulin dose and improving controller stability during the early phase of clamp studies. However, the robustness of a Smith's predictor-based controller should be carefully evaluated before implementation in closed-loop systems can be considered.

Computer Simulation↗
PubMed1991

Wearable system for acquisition, processing and storage of the signal from amperometric glucose sensors.

A wearable device for the acquisition, processing and storage of the signal from needle-type glucose sensors has been designed and developed as part of a project aimed at developing a portable artificial pancreas. The device is essential to assess the operational characteristics of miniaturized sensors in vivo. It can be connected to sensors operating at a constant potential of 0.65 Volts, and generating currents in the order of 10(-9) Amp. It is screened and equipped with filters that permit data recording and processing even in the presence of electrical noise. It can operate with sensors with different characteristics (1-200 nA full scale). The device has been designed to be worn by patients, so its weight and size have been kept to a minimum (250 g; 8.5 x 14.5 x 3.5 cm). It is powered by rechargeable Ni/Cd batteries allowing continuous operation for 72 h. The electronics consists of an analog card with operational amplifiers, and a digital one with a microprocessor (Intel 80C196, MCS-96 class, with internal 16-bit CPU supporting programs written in either C or Assembler language), a 32 Kb EPROM, and an 8 Kb RAM where the data are stored. The microprocessor can run either at 5 or 10 Mhz and features on-chip peripherals: an analog/digital (A/D) converter, a serial port (used to transfer data to a Personal Computer at the end of the 72 h), input-output (I/O) units at high-speed, and two timers. The device is programmed and prepared to operate by means of a second hand-held unit equipped with an LCD display and a 16-key numeric pad.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Glucose Self-Monitoring↗
PubMed1984

Metabolic effects of intensified insulin therapy.

Intensified insulin therapy is usually carried out either with multiple subcutaneous insulin injections (ICT: intensified conventional therapy) or with continuous subcutaneous insulin infusion (CSII) by minipumps. For two years we have been studying two matched groups of type I diabetic patients, treated with 3 daily insulin injections (ICT) and with CSII ( Microjet , Miles), respectively. Blood glucose control, as assessed by integrated mean blood glucose (MBG), was similar in both groups, but a better metabolic stability ('M' index of Schlichtkrull ) was evident in the CSII group. From the 24-hour profiles of plasma 'free' IRI and metabolites (glucose, beta-OH-butyrate, lactate, pyruvate, alanine), both the hepatic and peripheral underinsulinization and related metabolic alterations were still evident in both groups of patients. The number of hypoglycaemic episodes, recorded by home blood glucose monitoring, was similar in both groups of patients, while the perception of symptomatic hypoglycaemia seemed to be reduced in the patients treated with CSII.

Alanine↗
PubMedDate not supplied

Hormonal and metabolic responses in brittle diabetic patients during feedback intravenous insulin infusion.

Twenty-four hour profiles of blood hormones and intermediary metabolites were obtained in seven 'brittle' diabetic subjects during their usual insulin therapy and during feedback intravenous insulin infusion from an artificial pancreas (GCIIS). The results were compared to those in matched stable diabetics and normal controls. Although routine insulin doses were higher in the brittle group than in the stable group (164 +/- 32 (mean +/- SE) vs. 58 +/- 8 U/day, P less than 0.005) during routine therapy, plasma free insulin levels were equal (35 +/- 12 vs. 31 +/- 6 mU/l). In the brittle group feedback i.v. insulin infusion reduced daily requirements to normal levels (80 +/- 13 U/day, P less than 0.025; stable group 71 +/- 4 U/day, NS). On routine therapy blood glucose levels were not different in the two groups (brittle 10.5 +/- 1.6, stable 10.8 +/- 0.6 mmol/l) and were similarly corrected by the GCIIS (6.9 +/- 0.3 and 6.9 +/- 0.3 mmol/l, respectively). Blood lactate and pyruvate levels were markedly abnormal in the brittle group during routine therapy (lactate: brittle group 1.93 +/- 0.27 mmol/l, stable group 0.91 +/- 0.07 mmol/l, P less than 0.025), and this abnormality was not corrected by the GCIIS (1.75 +/- 0.32 and 0.88 +/- 0.08 mmol/l, P less than 0.005). Abnormalities were also found in profiles of blood alanine and glycerol, and serum cortisol. Blood ketone body levels did not differ between the two groups of patients. The results suggest a defect in insulin delivery from subcutaneous tissue into the plasma. These patients have a characteristic metabolic abnormality, unresponsive to short-term normoglycaemia, either as the result of long-term disturbance of diabetic control, or as a marker for the underlying hormonal or biochemical abnormality.

3-Hydroxybutyric Acid↗
PubMedDate not supplied

Kinetics and metabolic activity of biosynthetic NPH insulin evaluated by the glucose clamp technique.

The glucose clamp technique has been used to evaluate the metabolic activity of NPH biosynthetic insulin in diabetic subjects free from anti-insulin antibodies. After overnight blood glucose normalization with a glucose-controlled insulin infusion system (Biostator), an s.c. injection of NPH insulin was given in the abdominal region. The insulin dose (0.236 +/- 0.05 U/kg body wt) was related to the usual intermediate-acting insulin requirement in the morning. Glucose was clamped at 100 mg/dl by a feedback i.v. glucose infusion. The end of the action of s.c. injected insulin considered conventionally to be the time of the spontaneous rise of blood glucose to 110 mg/dl. Free insulin levels were higher and the length of action was longer after NPH porcine than after NPH biosynthetic human insulin (BHI) (area under the free insulin curve: porcine 1423 +/- 556 mU/L/h; BHI 1045 +/- 338 mU/L/h, P less than 0.05; length of action: porcine 16.0 +/- 3.2 h; BHI 13.7 +/- 0.9 h, P less than 0.05); the glucose requirement was higher after porcine (76.8 +/- 13.5 g) than after BHI (58.5 +/- 14.6 g) without reaching statistical significance. However, the metabolic activity of the bioavailable insulin (index of plasma free insulin activity) was similar for the two insulins (porcine 381 +/- 77.4, BHI 342.8 +/- 54.2 mU/L/g of glucose/h). We conclude that a difference in pharmacokinetics exists between NPH BHI and porcine NPH insulin, which makes the latter metabolically more active. The different behavior does not seem to be related to the insulin molecule itself but could be a consequence of the unequal content of protamine in the two pharmacologic preparations.

Adult↗