Michaela Riedl

Feasibility of a Mobile Phone–Based Data Service for Functional Insulin Treatment of Type 1 Diabetes Mellitus Patients

Background Patients with type 1 diabetes mellitus (DM1) have to be active participants in their treatment because they are inevitably responsible for their own day-to-day-care. Availability of mobile Internet access is advancing rapidly and mobile phones are now widely available at low cost. Thus, mobile phones have the potential to assist in daily diabetes management and to enable a telemedical interaction between patients and health care professionals. Objective The aim of the study was to evaluate the feasibility and user acceptance of a mobile phone–based data service to assist DM1 patients on intensive insulin treatment. Methods A software application called Diab-Memory (based on Java 2 Mobile Edition) has been developed to support patients when entering diabetes-related data with synchronization to the remote database at the monitoring center. The data were then processed to generate statistics and trends, which were provided for the patient and his/her health care professional via a Web portal. The system has been evaluated in the course of a clinical before-after pilot trial. Outcome measures focused on patients’ adherence to the therapy, availability of the monitoring system, and the effects on metabolic status. General user acceptance of the system was evaluated using a questionnaire. Results Ten patients (four female) with DM1 participated in the trial. Mean age was 36.6 years (± 11.0 years) and prestudy glycated hemoglobin (HbA1c) was 7.9% (± 1.1%). A total of 3850 log-ins were registered during the 3 months of the study. The total number of received datasets was 13003, which equates to an average of 14 transmitted parameters per patient per day. The service was well accepted by the patients (no dropouts), and data transmission via mobile phone was successful on the first attempt in 96.5% of cases. Upon completion of the study, a statistically significant improvement in metabolic control was observed (HbA1c: prestudy 7.9% ± 1.1% versus poststudy 7.5% ± 0.9%;P= .02). While there was a slight decrease in average blood glucose level (prestudy 141.8 mg/dL ± 22.5 mg/dL vs poststudy 141.2 mg/dL ± 23.1 mg/dL;P= .69), the difference was not statistically significant. Conclusion The results of the clinical pilot trial indicate that this proposed diabetes management system was well accepted by the patients and practical for daily usage. Thus, using the mobile phone as patient terminal seems to provide a ubiquitous, easy-to-use, and cost efficient solution for patient-centered data acquisition in the management of DM1. To confirm the promising results of the pilot trial further research has to be done to study long-term effects on glycemic control and cost-effectiveness.

Oxytocin alleviates the neuroendocrine and cytokine response to bacterial endotoxin in healthy men.

Oxytocin is a hormone and neurotransmitter found to have anti-inflammatory functions in rodents. Here we used experimental bacterial endotoxinemia to examine the role of exogenous oxytocin administration on innate immune responses in humans. Ten healthy men received, in a randomized, placebo-controlled, crossover design, placebo, oxytocin, LPS, and LPS + oxytocin. Oxytocin treatment resulted in a transient or prolonged reduction of endotoxin-induced increases in plasma ACTH, cortisol, procalcitonin, TNF-alpha, IL-1 receptor antagonist, IL-4, IL-6, macrophage inflammatory protein-1alpha, macrophage inflammatory protein-1beta, monocyte chemoattractant protein-1 (MCP-1), interferon-inducible protein 10, and VEGF. In vitro, oxytocin had no impact on LPS effects in releasing TNF-alpha, IL-6, and MCP-1 in monocytes and peripheral blood mononuclear cells from healthy human donors. In summary, oxytocin decreases the neuroendocrine and cytokine activation caused by bacterial endotoxin in men, possibly due to the pharmacological modulation of the cholinergic anti-inflammatory pathway. Oxytocin might be a candidate for the therapy of inflammatory diseases and conditions associated with high cytokine and VEGF levels.

The Relationship between Insulin Resistance and the Cardiovascular Biomarker Growth Differentiation Factor-15 in Obese Patients

BACKGROUND Growth differentiation factor-15 (GDF-15) is a stress-responsive cytokine linked to obesity comorbidities such as cardiovascular disease, inflammation, and cancer. GDF-15 also has adipokine properties and recently emerged as a prognostic biomarker for cardiovascular events. METHODS We evaluated the relationship of plasma GDF-15 concentrations with parameters of obesity, inflammation, and glucose and lipid metabolism in a cohort of 118 morbidly obese patients [mean (SD) age 37.2 (12) years, 89 females, 29 males] and 30 age- and sex-matched healthy lean individuals. All study participants underwent a 75-g oral glucose tolerance test; 28 patients were studied before and 1 year after Roux-en-Y gastric bypass surgery. RESULTS Obese individuals displayed increased plasma GDF-15 concentrations (P < 0.001), with highest concentrations observed in patients with type 2 diabetes. GDF-15 was positively correlated with age, waist-to-height ratio, mean arterial blood pressure, triglycerides, creatinine, glucose, insulin, C-peptide, hemoglobin A(1c), and homeostatic model assessment insulin resistance index and negatively correlated with oral glucose insulin sensitivity. Age, homeostatic model assessment index, oral glucose insulin sensitivity, and creatinine were independent predictors of GDF-15 concentrations. Roux-en-Y gastric bypass led to a significant reduction in weight, leptin, insulin, and insulin resistance, but further increased GDF-15 concentrations (P < 0.001). CONCLUSIONS The associations between circulating GDF-15 concentrations and age, insulin resistance, and creatinine might account for the additional cardiovascular predictive information of GDF-15 compared to traditional risk factors. Nevertheless, GDF-15 changes following bariatric surgery suggest an indirect relationship between GDF-15 and insulin resistance. The clinical utility of GDF-15 as a biomarker might be limited until the pathways directly controlling GDF-15 concentrations are better understood.

Plasma Osteopontin Increases After Bariatric Surgery and Correlates with Markers of Bone Turnover But Not with Insulin Resistance

CONTEXT Osteopontin (OPN) is a multifunctional protein involved in bone metabolism, cardiovascular disease, diabetes, and obesity. OPN levels are elevated in the plasma and adipose tissue of obese subjects, and are decreased with diet-induced weight loss. OBJECTIVE We investigated the effect of bariatric surgery on plasma OPN concentrations in morbidly obese patients. SETTING The study was performed at a university hospital. SUBJECTS We investigated 40 obese patients aged 43.1 +/- 1.8 yr, scheduled to undergo bariatric surgery. Roux-en-Y gastric bypass (RYGB) was performed in 30 subjects (27 females, three males), and laparoscopic adjustable gastric banding (LAGB) in 10 subjects (eight females, two males). STUDY DESIGN All patients were studied before and 1 yr (10.3-14.8 months) after the intervention. MAIN OUTCOME MEASURES OPN, leptin, C-reactive protein, insulin, the homeostatic model assessment insulin resistance index, calcium, 25-hydroxyvitamin D, C telopeptide, and osteocalcin were determined. RESULTS Both bariatric procedures significantly reduced body weight, body mass index, insulin, leptin, and C-reactive protein 1 yr after surgery. Plasma OPN increased from 31.4 +/- 3.8 to 52.8 +/- 3.7 ng/ml after RYGB (P < 0.001) and from 29.8 +/- 6.9 to 46.4 +/- 10.6 ng/ml after LAGB (P = 0.042). Preoperative OPN correlated with age, insulin, the homeostatic model assessment insulin resistance index, and postoperative OPN. Postoperative OPN correlated with C telopeptide and osteocalcin. CONCLUSIONS One year after RYGB and LAGB, plasma OPN levels significantly increased and correlated with biomarkers of bone turnover. Unlike other proinflammatory cytokines, OPN does not normalize but increases further after bariatric surgery.

Plasma NT-proBNP increases in response to LPS administration in healthy men

Circulating levels of B-type natriuretic peptide (BNP) and NH(2)-terminal-proBNP (NT-proBNP) increase in response to volume overload and help in the differential diagnosis of acute heart failure. Elevated plasma BNP levels are observed also in sepsis and do not always correspond to left ventricular dysfunction. Here, we investigated plasma NT-proBNP fluctuations in response to human bacterial endotoxinemia, an experimental model of systemic infection and inflammation. Escherichia coli endotoxin (LPS) (2 ng/kg) was administered to 10 healthy volunteers in a randomized, placebo-controlled, cross-over design. Plasma NT-proBNP, C-reactive protein (CRP), COOH terminal pro-endothelin-1 (CT-proET-1), and midregional-pro-adrenomedullin (MR-proADM) were measured at hourly intervals for 6 h. LPS administration induced a continuous increase in plasma NT-proBNP that reached peak values after 6 h (40.7 +/- 7.9 vs. 16.1 +/- 3.2 pg/ml in placebo days, mean +/- SE; P = 0.023). The profile of changes in NT-proBNP correlated to changes in body temperature (P < 0.001), heart rate (P = 0.005), CRP (P < 0.001), and CT-proET-1 (P = 0.008), but not to blood pressure values. Our results demonstrate that plasma NT-proBNP increases in a model of systemic infection/inflammation in healthy men with normal heart function. This finding emphasizes the necessity to consider concomitant infections when interpreting elevated circulating NT-proBNP concentrations.

NT-proBNP has a high negative predictive value to rule-out short-term cardiovascular events in patients with diabetes mellitus

AIMS This study evaluated the predictive value of NT-proBNP for patients with diabetes mellitus and compared the prognostic aptitude of this neurohumoral marker to traditional markers of cardiovascular events. METHODS AND RESULTS A prospective observational study was conducted in 631 diabetic patients. The composite endpoint consisted of unplanned hospitalization for cardiovascular events or death within the observation period of 12 months. Of all variables analysed (age, gender, history of hypertension, ischaemic heart disease/any cardiac disease, smoking, duration of diabetes, body mass index, blood pressure, New York Heart Association-class, Dyspnoea score, Minnesota Living with Heart Failure Questionnaire, LDL-cholesterol, HbA(1c), creatinine, glomerular filtration rate), the logarithm of NT-proBNP gave the most potent information in a stepwise Cox regression analysis (P < 0.0001). Bootstrapping with 500 samples supports this result in 95% samples. The negative predictive value of a normal value (<125 pg/mL) of NT-proBNP for short-term cardiovascular events in diabetic patients is 98%. CONCLUSION We have demonstrated a strong and independent correlation between NT-proBNP and short-term prognosis of cardiovascular events for patients with diabetes mellitus. With a high negative predictive value it can identify individuals who are not at intermediate risk for cardiovascular events. NT-proBNP proved to be of higher predictive value than traditional cardiovascular markers, in this unselected cohort.

The influence of growth hormone substitution therapy on erythroid and myeloid progenitor cells and on peripheral blood cells in adult patients with growth hormone deficiency.

It has been reported that hypophysectomized rats exhibit normochromic, normocytic anaemia. Pancytopenia with impaired DNA synthesis in the bone marrow can be restored in these hypophysectomized rats by syngeneic pituitary grafts placed under the kidney capsule or treatment with growth hormone (GH). Until now, adults with hypopituitarism have received adequate replacement therapy with thyroxine, cortisol and sex steroids, but not with GH. We therefore investigated the effects of GH replacement therapy on the proliferation and differentiation of erythroid and myeloid progenitor and peripheral blood cells in 11 adult patients with growth hormone deficiency in a double‐blind, placebo‐controlled study for the first 6 months of therapy. The placebo group showed no changes during the first 6 months without therapy in either insulin‐like growth factor I (IGF‐I) levels, erythroid and myeloid progenitor precursor cells or peripheral blood cells. After commencement of GH therapy, IGF‐I levels rose significantly during 24 months of therapy from 75.3±13.5 to 225±34.7ngmL−1 (P<0.001). Erythroid and myeloid progenitor precursor cells showed a steep and significant increase after 18 and 24 months of therapy (erythroid: from 10.7±3.5 to 261.4±79.8, P<0.02, after 18 months and to 276.8±149.8 × 105 mononuclear cell colonies, P<0.03, after 24 months; granulocyte–macrophage colony‐forming units: from 39.7±9.8 to 316.9±124.6, P<0.002, after 18 months and to 366±188.7×105 mononuclear cell colonies, P<0.03, after 24 months), whereas the peripheral red and white blood cells exhibited only minimal non‐significant changes. The principal regulators of erythropoiesis, such as erythropoietin, and parameters reflecting erythropoiesis in the peripheral blood, such as reticulocytes, remained almost unchanged throughout the whole study period. We therefore conclude that patients with GH deficiency do not have anaemia, but have haematopoietic precursor cells in the lower normal range, and that GH substitution therapy over a period of 24 months has a marked effect on erythroid and myeloid progenitor precursor cells but only negligible effects on peripheral blood cells in GH‐deficient adults.

Clinical significance of smell and taste disorders in patients with diabetes mellitus

Chemosensory dysfunction has been reported in patients with diabetes mellitus (DM). However, the clinical significance in relation to the disease stage remains unclear. The aim of this investigation was to assess olfactory and gustatory function with valid clinical tests in patients with DM types 1 and 2 with and without accompanying diseases. Seventy-six patients with DM were divided into three groups according to disease stage. Taste function was tested by means of impregnated paper strips and smell function was screened using a five-item smell identification test. The results of the patients with uncomplicated DM were compared with the results from 29 healthy subjects. The results showed no significant differences in smell and taste function between patients with uncomplicated DM and healthy subjects. However, patients with additional diseases exhibited decreased smell acuity. Moreover, patients with DM type 2 showed impaired smell function compared with patients with DM type 1.

Cholinergic Regulation of Ghrelin and Peptide YY Release May Be Impaired in Obesity

OBJECTIVE—Ghrelin and peptide YY (PYY) are both hormones derived from the gastrointestinal tract involved in appetite regulation. The cholinergic part of the vagal nerve is involved in the regulation of glucose and insulin. The aim of this study was to examine the effects of the cholinergic antagonist atropine on ghrelin, PYY, glucose, and insulin under basal conditions and after meal ingestion in lean and obese subjects. REASEARCH DESIGN AND METHODS—Eight lean and eight obese subjects were included in a randomized, double-blind, placebo-controlled crossover study with 4 study days in randomized order (atropine/placebo ± breakfast). Plasma ghrelin, PYY, insulin, and glucose were measured. Hunger and satiety feelings were rated on a 10-cm visual analog scale. RESULTS—In lean individuals, atropine led to a decrease in ghrelin concentrations comparable and nonadditive with breakfast ingestion and a significant decrease in both basal and meal-induced PYY concentrations. In obese subjects, atropine did not significantly change ghrelin or PYY concentrations, whereas it induced a comparable increase in heart rate and meal-induced glucose concentrations in the two study groups. Only lean, not obese, subjects experienced sustained feelings of satiety after breakfast. CONCLUSIONS—The impaired cholinergic regulation of the postprandial drop in ghrelin concentrations and rise in PYY concentrations might be part of the deregulated food intake in obese subjects.

Plasma MR-proADM Correlates to BMI and Decreases in Relation to Leptin After Gastric Bypass Surgery

Adrenomedullin (ADM) is a vasoactive peptide found to be related to obesity and its comorbidities: type 2 diabetes, hypertension, atherosclerosis, and coronary heart disease. ADM is increased both in plasma and in adipose tissue of obese individuals when compared to lean subjects and is considered as a member of the adipokine family. We determined plasma midregional proadrenomedullin (MR‐proADM) concentrations in a cohort of 357 subjects with BMI ranging from 17.5 to 42.3 kg/m2 and no additional medical history. In parallel, 28 severely obese patients scheduled to undergo laparoscopic Roux‐en‐Y gastric bypass (RYGB) surgery were studied at two time points: before and 1 year after surgery. Outcome measurements were: MR‐proADM, cortisol, leptin, C‐reactive protein (CRP) thyroid‐stimulating hormone (TSH), creatinine and metabolic parameters. BMI correlated significantly to plasma MR‐proADM levels (r = 0.714, P < 0.001), also after adjustment for age and gender (r = 0.767, P < 0.001). In obese subjects, there was a positive relationship between MR‐proADM and leptin (r = 0.511, P = 0.006). Following RYGB, plasma MR‐proADM decreased from 0.76 ± 0.03 to 0.62 ± 0.02 pg/ml (P < 0.0001). RYGB‐induced changes in MR‐proADM correlated significantly to changes in leptin (r = 0.533, P = 0.004) and in CRP (r = 0.429, P = 0.023). We conclude that BMI is an independent predictor of circulating MR‐proADM levels. Weight loss after RYGB is associated with a significant decrease in plasma MR‐proADM, which is related to surgery‐induced changes in both circulating leptin and systemic inflammation.