Impact of blinded retrospective continuous glucose monitoring on clinical decision making and glycemic control in persons with type 2 diabetes on insulin therapy

BACKGROUND AND AIMS

Blinded retrospective continuous glucose monitoring (rCGM) provides detailed information about real-life glycaemic profile. In persons with type 2 diabetes without adequate glycaemic control, the structured introduction of rCGM may be beneficial to sustain improvements in diabetes management.

METHODS AND RESULTS

102 individuals with insulin-treated type 2 diabetes, age less than 66 years old and HbA1c >7.5%, were recruited. Participants performed a 7-day blinded rCGM (iPro2) every four months for one year. Biochemical, anthropometric, and rCGM data was collected. Participants' and healthcare professionals' perceptions were assessed. 90 participants completed the protocol. HbA1c was 9.1 ± 0.1% one year prior to enrolment and 9.4 ± 0.1% at enrolment (p < 0.01). With the rCGM-based intervention, a decrease in HbA1c was achieved at 4 months (8.4 ± 0.1%, p < 0.0001), and 12 months (8.1 ± 0.1%, p < 0.0001). A significant increase in time-in-range was observed (50.8 ± 2.4 at baseline vs 61.5 ± 2.2% at 12 months, for 70-180 mg/dL, p < 0.001), with no difference in exposure time to hypoglycaemia. After 12 months, there was an increase in self-reported diabetes treatment satisfaction (p < 0.05).

CONCLUSION

In persons with type 2 diabetes and poor metabolic control, specific data from blinded rCGM informed therapeutic changes and referral to targeted education consultations on nutrition and insulin administration technique. Therapeutic changes were made more frequently and targeted to changes in medication dose, timing, and/or type, as well as to lifestyle. Together, these brought significant improvements in clinical outcomes, effective shared decision-making, and satisfaction with treatment.

REGISTRATION NUMBER

NCT04141111.

Differential Age-Dependent Mitochondrial Dysfunction, Oxidative Stress, and Apoptosis Induced by Neonatal Hypoxia-Ischemia in the Immature Rat Brain

Neonatal hypoxia-ischemia (HI) is among the main causes of mortality and morbidity in newborns. Experimental studies show that the immature rat brain is less susceptible to HI injury, suggesting that changes that occur during the first days of life drastically alter its susceptibility. Among the main developmental changes observed is the mitochondrial function, namely, the tricarboxylic acid (TCA) cycle and respiratory complex (RC) activities. Therefore, in the present study, we investigated the influence of neonatal HI on mitochondrial functions, redox homeostasis, and cell damage at different postnatal ages in the hippocampus of neonate rats. For this purpose, animals were divided into four groups: sham postnatal day 3 (ShP3), HIP3, ShP11, and HIP11. We initially observed increased apoptosis in the HIP11 group only, indicating a higher susceptibility of these animals to brain injury. Mitochondrial damage, as determined by flow cytometry showing mitochondrial swelling and loss of mitochondrial membrane potential, was also demonstrated only in the HIP11 group. This was consistent with the decreased mitochondrial oxygen consumption, reduced TCA cycle enzymes, and RC activities and induction of oxidative stress in this group of animals. Considering that HIP3 and the sham animals showed no alteration of mitochondrial functions, redox homeostasis, and showed no apoptosis, our data suggest an age-dependent vulnerability of the hippocampus to hypoxia-ischemia. The present results highlight age-dependent metabolic differences in the brain of neonate rats submitted to HI indicating that different treatments might be needed for HI newborns with different gestational ages.

Diabetes patient’s pharmacovigilance knowledge and risk perception: the influence of being part of a patient organisation

Objective:

The aim was to assess the perception of risk for developing adverse drug reaction (ADRs) and knowledge, attitudes and opinions regarding pharmacovigilance in diabetic patients, and to investigate the effect of being a member of a patient organisation for diabetes on these factors, in comparison with other patients.

Methods:

A cross-sectional study looking for patients’ risk perception of experiencing ADRs. Diabetes patients followed at the Portuguese Diabetes Association (APDP) were included, together with two comparison groups (patients with and without diabetes). Kruskal-Wallis followed by post hoc Dunn’s multiple-comparison test were used to compare patients’ groups.

Results:

A total of 314 patients participated in the survey (104 followed at APDP, 106 with diabetes not followed at APDP and 104 without diabetes diagnosis that used chronic medication). APDP patients presented higher risk perception scores for medicines related to their disease compared with two groups. Those patients affirmed that doctors explained possible ADRs on medication to them, and showed higher intention to report ADRs in the future if serious or unexpected.

Conclusions:

Patients with diabetes showed greater understanding of ADRs and higher need to report them than patients without diabetes. They would like to have more information about general ADRs related to anti-diabetic medication and present higher intention to acquire information on how and when to report compared with non-diabetic patients. Patients followed in APDP presented higher score of risk perception, which could be influenced by the presence of the diabetes disease in the patients’ life, by their previous experiences using medicines, but also by information received from the patient organisation. The two groups of patients with diabetes have different experiences of the disease, but both present higher perception of side effects related with medicines they use respectively in their diabetes type. Hence, patient organisations are well positioned to be a source where patients can obtain reliable information, changing their attitudes and perceptions about the disease and drug treatments.

Review of methods for detecting glycemic disorders

Prediabetes (intermediate hyperglycemia) consists of two abnormalities, impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) detected by a standardized 75-gram oral glucose tolerance test (OGTT). Individuals with isolated IGT or combined IFG and IGT have increased risk for developing type 2 diabetes (T2D) and cardiovascular disease (CVD). Diagnosing prediabetes early and accurately is critical in order to refer high-risk individuals for intensive lifestyle modification. However, there is currently no international consensus for diagnosing prediabetes with HbA1c or glucose measurements based upon American Diabetes Association (ADA) and the World Health Organization (WHO) criteria that identify different populations at risk for progressing to diabetes. Various caveats affecting the accuracy of interpreting the HbA1c including genetics complicate this further. This review describes established methods for detecting glucose disorders based upon glucose and HbA1c parameters as well as novel approaches including the 1-hour plasma glucose (1-h PG), glucose challenge test (GCT), shape of the glucose curve, genetics, continuous glucose monitoring (CGM), measures of insulin secretion and sensitivity, metabolomics, and ancillary tools such as fructosamine, glycated albumin (GA), 1,5- anhydroglucitol (1,5-AG). Of the approaches considered, the 1-h PG has considerable potential as a biomarker for detecting glucose disorders if confirmed by additional data including health economic analysis. Whether the 1-h OGTT is superior to genetics and omics in providing greater precision for individualized treatment requires further investigation. These methods will need to demonstrate substantially superiority to simpler tools for detecting glucose disorders to justify their cost and complexity.

Prevalence, awareness, treatment and control of diabetes in Portugal: Results from the first National Health examination Survey (INSEF 2015)

AIMS

Diabetes Mellitus is a major public health threat worldwide and continues to increase in numbers and significance. Estimates of diabetes prevalence, awareness, treatment and control are essential to effectively monitor its trends, plan and evaluate interventions.

METHODS

We conducted a nationwide health examination survey in the population residing in Portugal aged between 25 and 74 years old in 2015. It consisted in a cross sectional prevalence study which included the measurement of HbA1c, a physical examination and a general health interview of a probabilistic sample of 4911 individuals (Authorization n°9348/2010 of the National Committee for Data Protection).

RESULTS

The overall prevalence of diabetes was 9.9% (95%CI: 8.4; 11.5). It was higher in males than in females (12.1% vs 7.8%). Diabetes was more prevalent among individuals of lower education and without any professional activity. The majority of persons with diabetes was aware of their condition (87.1%) and was taking antidiabetic medication (79.7%). Of these, 63.2% had glycated hemoglobin levels lower than 7.0% (53 mmol/mol), but the majority failed to comply with the LDL and blood pressure recommended clinical targets (71.9% and 59.0%). Similarly, the prevalence of prediabetes was 16%, higher among women than men (17.5% vs 14.4%).

CONCLUSION

The prevalence of diabetes and prediabetes remains higher than the global and European estimates, although there is increasing awareness of this disorder.

Beyond self-monitored plasma glucose and HbA1c: the role of non-traditional glycaemic markers in gestational diabetes mellitus

Strict glycaemic management is the cornerstone of metabolic control in gestational diabetes mellitus (GDM). Current monitoring standards involve self-monitoring plasma glucose (SMBG) and haemoglobin A1c (HbA1c). However, both have important limitations. SMBG only reflects instantaneous blood glucose and the inconvenience of self-collecting blood frequently results in poor compliance. HbA1c provides information on blood glucose levels from the previous 2 to 3 months and it is influenced by iron-deficient states, common during pregnancy. There is an urgent need for new shorter-term glycaemic markers, as glycated albumin, fructosamine or 1,5-anhydroglucitol. Glycated albumin seems especially interesting as it provides information on blood glucose levels over the foregoing 2-3 weeks and it is not influenced by iron deficiency or the dilutional anaemia of pregnancy. Fructosamine has a precise and inexpensive measurement and it is not affected by haemoglobin characteristics. This review further discusses the potential value of these non-traditional indicators of glycaemic control in patients with GDM, outlining their possible future applications.

Trends in diabetes incidence from 1992 to 2015 and projections for 2024: A Portuguese General Practitioner's Network study

BACKGROUND

Diabetes is known as a major cause of morbidity and mortality worldwide. Portugal is known as the European country with the highest prevalence of this disease. While diabetes prevalence data is updated annually in Portugal, the General Practitioner's (GP) Sentinel Network represents the only data source on diabetes incidence. This study describes the trends in Diabetes incidence, between 1992 and 2015, and estimate projections for the future incidence rates in Portugal until 2024.

METHODS

An ecological time-series study was conducted using data from GP Sentinel Network between 1992 and 2015. Family doctors reported all new cases of Diabetes in their patients' lists. Annual trends were estimated through Poisson regression models as well as the future incidence rates (until 2024), sex and age group stratified. Incidence rate projections were adjusted to the distribution of the resident Portuguese population given Statistics Portugal projections.

RESULTS

The average increase in Diabetes incidence rate was in total 4.29% (CI95% 3.80-4.80) per year under study. Until 1998-2000, the annual incidence rate was higher in women, and from 1998-2000 to 2013-2015 turn out to be higher in men. The incidence rate projected for 2022-2024 was 972.77/10(5) inhabitants in total, and 846.74/10(5) and 1114.42/10(5), respectively, in women and men.

CONCLUSIONS

This is the first study in Portugal to estimate diabetes incidence rate projections. The disturbing reported projections seem realistic if things continue as in the past. Actually, effective public health policies will need to be undertaken to minimize this alarming future scenario.

Diabetes hinders community-acquired pneumonia outcomes in hospitalized patients

OBJECTIVES

This study aimed to estimate the prevalence of diabetes mellitus (DM) in hospitalized patients with community-acquired pneumonia (CAP) and its impact on hospital length of stay and in-hospital mortality.

RESEARCH DESIGN AND METHODS

We carried out a retrospective, nationwide register analysis of CAP in adult patients admitted to Portuguese hospitals between 2009 and 2012. Anonymous data from 157 291 adult patients with CAP were extracted from the National Hospital Discharge Database and we performed a DM-conditioned analysis stratified by age, sex and year of hospitalization.

RESULTS

The 74 175 CAP episodes that matched the inclusion criteria showed a high burden of DM that tended to increase over time, from 23.7% in 2009 to 28.1% in 2012. Interestingly, patients with CAP had high DM prevalence in the context of the national DM prevalence. Episodes of CAP in patients with DM had on average 0.8 days longer hospital stay as compared to patients without DM (p<0.0001), totaling a surplus of 15 370 days of stay attributable to DM in 19 212 admissions. In-hospital mortality was also significantly higher in patients with CAP who have DM (15.2%) versus those who have DM (13.5%) (p=0.002).

CONCLUSIONS

Our analysis revealed that DM prevalence was significantly increased within CAP hospital admissions, reinforcing other studies' findings that suggest that DM is a risk factor for CAP. Since patients with CAP who have DM have longer hospitalization time and higher mortality rates, these results hold informative value for patient guidance and healthcare strategies.

HbA1c, Fructosamine, and Glycated Albumin in the Detection of Dysglycaemic Conditions

Glycated haemoglobin (HbA1c) is currently the gold standard for glucose monitoring in patients with diabetes, and has been increasingly adopted as a criteria for diabetes diagnosis. However, conditions that determine alterations in haemoglobin metabolism can interfere with the reliability of HbA1c measurements. Glycated albumin and fructosamine (total glycated serum proteins) are alternative markers of glycaemia, which have been recognised to provide additional information to HbA1c or to provide a reliable measure when HbA1c is observed not to be dependable. Additionally, while HbA1c monitors the exposure to circulating glycaemia in the previous 3 months, glycated albumin and fructosamine represent exposure for a shorter period, which may be beneficial to monitor rapid metabolic alterations or changes in diabetes treatment. The present review further discusses the relative value of HbA1c, glycated albumin, and fructosamine, in prediabetes and diabetes diagnosis, evaluation of glucose variability, and complications risk prediction. Also, a novel molecular role for albumin is presented by which glycated albumin contributes to glucose intolerance development and thus to progression to diabetes, besides the role of glycated albumin as a pro-atherogenic factor.

Postprandial insulin resistance in Zucker diabetic fatty rats is associated with parasympathetic-nitric oxide axis deficiencies

The Zucker diabetic fatty (ZDF) rat is an obesity and type 2 diabetes model. Progression to diabetes is well characterised in ZDF rats, but only in the fasted state. We evaluated the mechanisms underlying postprandial insulin resistance in young ZDF rats. We tested the hypothesis that the overall postprandial action of insulin is affected in ZDF rats as a result of impairment of the hepatic parasympathetic-nitric oxide (PSN-NO) axis and/or glutathione (GSH), resulting in decreased indirect (PSN-NO axis) and direct actions of insulin. Nine-week-old male ZDF rats and lean Zucker rats (LZR, controls) were used. The action of insulin was assessed in the fed state before and after parasympathetic antagonism atropine. Basal hepatic NO and GSH were measured, as well as NO synthase (NOS) and γ-glutamyl-cysteine synthethase (GCS) activity and expression. ZDF rats presented postprandial hyperglycaemia (ZDF, 201.4 ± 12.9 mg/dl; LZR, 107.7 ± 4.3 mg/dl), but not insulinopaenia (ZDF, 5.9 ± 0.8 ng/ml; LZR, 1.5 ± 0.3 ng/ml). Total postprandial insulin resistance was observed (ZDF, 78.6 ± 7.5 mg glucose/kg; LZR, 289.2 ± 24.7 mg glucose/kg), with a decrease in both the direct action of insulin (ZDF, 54.8 ± 7.0 mg glucose/kg; LZR, 173.3 ± 20.5 mg glucose/kg) and the PSN-NO axis (ZDF, 24.5 ± 3.9 mg glucose/kg; LZR, 115.9 ± 19.4 mg glucose/kg). Hepatic NO (ZDF, 117.2 ± 11.4 μmol/g tissue; LZR, 164.6 ± 4.9 μmol/g tissue) and GSH (ZDF, 4.9 ± 0.3 μmol/g; LZR, 5.9 ± 0.2 μmol/g) were also compromised as a result of decreased NOS and GCS activity, respectively. These results suggest a compromise of the mechanism responsible for potentiating insulin action after a meal in ZDF rats. We show that defective PSN-NO axis and GSH synthesis, together with an impaired direct action of insulin, appears to contribute to postprandial insulin resistance in this model.

Loss of postprandial insulin sensitization during aging

With aging, there is a decrease in parasympathetic nervous activity. Since the hepatic parasympathetic nerves (HPNs) are essential to the disposal of nutrients, through the hepatic insulin sensitizing substance (HISS), we tested the hypothesis that aging leads to a lowering of postprandial glucose disposal by a decrease of the HISS-dependent component of insulin action. Insulin sensitivity was quantified in fed or fasted, male and female Wistar rats (from 6 to 52 weeks), using a euglycemic clamp. The HISS-dependent component was quantified by administration of the muscarinic antagonist atropine. Total insulin action decreased gradually up to 52 weeks of age: The HISS-independent component of insulin action decreased until 9 weeks of age and remained unchanged thereafter; the HISS-dependent component decreased from 9 weeks of age throughout aging. The continuous decrease of HISS action, uncovered by blocking the HPN, is the key phenomenon for the gradual decrease of insulin sensitivity with aging.

Hepatic parasympathetic role in insulin resistance on an animal model of hypertension

The hepatic insulin sensitizing substance (HISS) pathway, which includes the hepatic parasympathetic nerves and hepatic nitric oxide (HNO), has been shown to be crucial to the action of insulin on glucose metabolism. Insulin resistance in essential hypertension has been related to parasympathetic dysfunction; thus, we tested the hypothesis that the HISS pathway is impaired in spontaneously hypertensive rats (SHR) when compared with their normotensive controls, Wistar (WIS) and Wistar Kyoto (WKY) rats. A modified euglycemic clamp quantified insulin sensitivity. Differentiation of the HISS-dependent and HISS-independent components of insulin action was achieved by administration of a muscarinic receptor antagonist (atropine, 3 mg/kg) or of a nitric oxide synthase inhibitor (N(g)-methyl-arginine, 0.73 mg/kg). Both SHR and WKY had lower postprandial total insulin action when compared with WIS (209.1 +/- 13.6 for WKY and 217.8 +/- 19.8 for SHR vs 296.1 +/- 16.9 mg glucose/kg body weight for WIS, P < .05). Furthermore, we observed that this is due to a decrease of the HISS-dependent component of insulin action (154.8 +/- 16.4 for WIS vs 87.1 +/- 14.5 for WKY and 55.9 +/- 15.6 mg glucose/kg body weight for SHR; P < .05 and P < .001, respectively; data concerning the atropine protocol). Blockade of HISS action by inhibition of hepatic nitric oxide synthase with N(g)-methyl-arginine showed similar results to those obtained with atropine, suggesting that they indeed act through the same pathway. In conclusion, our results support our hypothesis that impairment of the HISS pathway is responsible for the development of insulin resistance between WIS and SHR.

Insulin resistance in two animal models of obesity: A comparison of HISS-dependent and HISS-independent insulin action in high-fat diet-fed and Zucker rats

Normal postprandial insulin sensitivity depends on the action of the hepatic insulin sensitizing substance (HISS), which requires hepatic parasympathetic nerve activation. Since HISS action is impaired in several pathological models, including the genetically-modified obese Zucker rat (OZR), we compared the HISS-dependent and HISS-independent components of insulin action between the OZR model, and the high-fat diet (HFD)-fed rats. We hypothesize that both models present an impaired HISS action, accounting for the decrease in insulin sensitivity. Male Sprague-Dawley rats fed a HFD for 1 week (n = 5) and OZR (n = 5) were used as obese models. Standard diet-fed (STD, n = 5) and lean Zucker rats (LZR, n = 6) were the HFD and OZR non-obese controls, respectively. Rats were 9-weeks-old when tested. Insulin sensitivity was measured in the fed state, before and after atropine blockade of HISS release), using the Rapid Insulin Sensitivity Test (RIST, mg glucose/kg bw). HISS-dependent action was the difference between control and post-atropine RISTs. HISS action was impaired in both the obese groups (HFD vs STD: 40.1 +/- 5.0 vs 117.0 +/- 3.8 mg glucose/kg bw, p < 0.001; OZR vs LZR: 34.4 +/- 12.8 vs 115.9 +/- 19.4 mg glucose/kg bw, p < 0.01), whereas the HISS-independent component (post-atropine RIST), i.e., insulin action per se, was decreased only in the OZR (OZR vs LZR: 39.3 +/- 3.5 vs 173.3 +/- 20.5 mg glucose/kg bw, p < 0.001). According to our data, the insulin resistance mechanisms are different in the two obesity models studied: in the HFD-fed rats, only the HISS-dependent component is impaired, whereas in the OZR both components of nsulin action are equally impaired.

Insulin resistance induced by sucrose feeding in rats is due to an impairment of the hepatic parasympathetic nerves

AIMS/HYPOTHESIS

A considerable proportion of whole-body insulin-stimulated glucose uptake is dependent upon the hepatic insulin-sensitising substance (HISS) in a pathway mediated by the hepatic parasympathetic nerves (HPNs). We tested the hypothesis that a high-sucrose diet leads to the impairment of the HPN-dependent component of insulin action.

METHODS

We quantified insulin sensitivity using the rapid insulin sensitivity test, a modified euglycaemic clamp. Quantification of the HPN-dependent component was achieved by administration of a muscarinic receptor antagonist (atropine, 3 mg/kg).

RESULTS

Insulin sensitivity was higher in standard-fed than in sucrose-fed Wistar rats (305.6+/-34.1 vs 193.9+/-13.7 mg glucose/kg body weight; p<0.005) and Sprague-Dawley rats (196.4+/-5.9 vs 95.5+/-16.3 mg glucose/kg body weight; p<0.01). The HPN-independent component was similar in the two diet groups. Insulin resistance was entirely due to an impairment of the HPN-dependent component in both Wistar rats (164.3+/-28.1 [standard-fed] vs 26.5+/-7.5 [sucrose-fed] mg glucose/kg body weight; p<0.0001) and Sprague-Dawley rats (111.7+/-9.5 vs 35.3+/-21.4 mg glucose/kg body weight; p<0.01). Furthermore, HPN-dependent insulin resistance in Sprague-Dawley rats was already evident after 2 weeks of a high-sucrose diet (28.5+/-7.6 [2 weeks], 35.3+/-21.4 [6 weeks], 17.9+/-5.4 [9 weeks] mg glucose/kg body weight) and was independent of the nature of sucrose supplementation (12.3+/-4.7 [solid] and 17.9+/-5.4 [liquid] mg glucose/kg body weight).

CONCLUSIONS/INTERPRETATION

Our results support the hypothesis that insulin resistance caused by sucrose feeding is due to an impairment of the HPN-dependent component of insulin action, leading to a dysfunction of the HISS pathway.

Defective hepatic nitric oxide action results in HISS-dependent insulin resistance in spontaneously hypertensive rats

Peripheral insulin sensitivity is dependent on the action of Hepatic Insulin Sensitizing Substance (HISS), in which hepatic NO (HNO) plays an important role. Insulin resistance has been associated with hypertension. NO action is known to be impaired in Spontaneously Hypertensive Rat (SHR) hypertension models. We tested the hypothesis that the HNO pathway is compromised in SHR, resulting in HISS-dependent insulin resistance. Wistar rats (Wis) were the normotensive controls. Insulin sensitivity was evaluated through the Rapid Insulin Sensitivity Test (RIST), a modified euglycemic clamp. A clamp was performed in basal state (control RIST), followed by ipv administration of the NO synthase (NOS) competitive antagonist L-NMMA (0.73 mg/kg) and a RIST post L-NMMA. HISS-dependent insulin sensitivity was assessed by subtracting the RIST post-L-NMMA from the control RIST and is represented as the resultant insulin sensitivity inhibition. In SHR ipv L-NMMA induced 26+/-5% insulin sensitivity inhibition (187.5+/-15.3 mg glucose/kg, n=6; P<0.05), whereas in Wis, ipv L-NMMA induced 53.8+/-5.9% insulin sensitivity inhibition (138.2+/-14.7 mg glucose/kg, n=6, P<0.05), significantly higher than in SHR (P<0.01). Our results suggest that functional HNO is essential to achieve maximal insulin sensitivity and that HNO action is compromised in hypertension, resulting in HISS-dependent insulin resistance.