Cambridge hybrid closed-loop algorithm in children and adolescents with type 1 diabetes: a multicentre 6-month randomised controlled trial

BACKGROUND

Closed-loop insulin delivery systems have the potential to address suboptimal glucose control in children and adolescents with type 1 diabetes. We compared safety and efficacy of the Cambridge hybrid closed-loop algorithm with usual care over 6 months in this population.

METHODS

In a multicentre, multinational, parallel randomised controlled trial, participants aged 6-18 years using insulin pump therapy were recruited at seven UK and five US paediatric diabetes centres. Key inclusion criteria were diagnosis of type 1 diabetes for at least 12 months, insulin pump therapy for at least 3 months, and screening HbA1c levels between 53 and 86 mmol/mol (7·0-10·0%). Using block randomisation and central randomisation software, we randomly assigned participants to either closed-loop insulin delivery (closed-loop group) or to usual care with insulin pump therapy (control group) for 6 months. Randomisation was stratified at each centre by local baseline HbA1c. The Cambridge closed-loop algorithm running on a smartphone was used with either (1) a modified Medtronic 640G pump, Medtronic Guardian 3 sensor, and Medtronic prototype phone enclosure (FlorenceM configuration), or (2) a Sooil Dana RS pump and Dexcom G6 sensor (CamAPS FX configuration). The primary endpoint was change in HbA1c at 6 months combining data from both configurations. The primary analysis was done in all randomised patients (intention to treat). Trial registration ClinicalTrials.gov, NCT02925299.

FINDINGS

Of 147 people initially screened, 133 participants (mean age 13·0 years [SD 2·8]; 57% female, 43% male) were randomly assigned to either the closed-loop group (n=65) or the control group (n=68). Mean baseline HbA1c was 8·2% (SD 0·7) in the closed-loop group and 8·3% (0·7) in the control group. At 6 months, HbA1c was lower in the closed-loop group than in the control group (between-group difference -3·5 mmol/mol (95% CI -6·5 to -0·5 [-0·32 percentage points, -0·59 to -0·04]; p=0·023). Closed-loop usage was low with FlorenceM due to failing phone enclosures (median 40% [IQR 26-53]), but consistently high with CamAPS FX (93% [88-96]), impacting efficacy. A total of 155 adverse events occurred after randomisation (67 in the closed-loop group, 88 in the control group), including seven severe hypoglycaemia events (four in the closed-loop group, three in the control group), two diabetic ketoacidosis events (both in the closed-loop group), and two non-treatment-related serious adverse events. There were 23 reportable hyperglycaemia events (11 in the closed-loop group, 12 in the control group), which did not meet criteria for diabetic ketoacidosis.

INTERPRETATION

The Cambridge hybrid closed-loop algorithm had an acceptable safety profile, and improved glycaemic control in children and adolescents with type 1 diabetes. To ensure optimal efficacy of the closed-loop system, usage needs to be consistently high, as demonstrated with CamAPS FX.

FUNDING

National Institute of Diabetes and Digestive and Kidney Diseases.

REDUCE-IT: outcomes by baseline statin type

Background

REDUCE-IT (Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial) randomized 8,179 statin-treated patients with elevated triglycerides and increased cardiovascular (CV) risk to either icosapent ethyl (IPE), a pure, stable prescription form of eicosapentaenoic acid, 4g/day or placebo. IPE significantly reduced time to first occurrence of the primary composite endpoint of major adverse CV events (CV death, nonfatal myocardial infarction [MI], nonfatal stroke, coronary revascularization, or hospitalization for unstable angina) (HR 0.75, CI 0.68–0.83) and key secondary endpoint events (composite of CV death, nonfatal MI, or nonfatal stroke) (HR 0.74, CI 0.65–0.83) versus placebo (all p<0.0001). A modest reduction in placebo-corrected LDL-C was observed (−6.6%; p<0.0001). The mechanisms for the CV benefit of icosapent ethyl are not fully understood.

Purpose

Explore the impact of statin type and lipophilic/lipophobic category on outcomes, and on LDL-C, to further consider the possible relevance of LDL-C pathways to the observed CV benefit of icosapent ethyl.

Methods

Primary and key secondary endpoint analyses and LDL-C changes from baseline were explored by individual statin type (atorvastatin, simvastatin, rosuvastatin, or pravastatin) at baseline, and then by categorizing these statins into lipophilic (i.e., hydrophobic: atorvastatin, simvastatin) and lipophobic (i.e., hydrophilic: rosuvastatin, pravastatin) statin groups; 96.1% of patients fell within these individual statin groups.

Results

CV outcomes were similar across statin types (interaction p=0.61) and lipophilic/lipophobic categories (interaction p=0.51) (Figure). Statin type and category had a similar lack of meaningful impact on the modest placebo-corrected median LDL-C changes from baseline to one year, which ranged from −5.8 to −8.4% (all p≤0.0003).

Conclusion

No meaningful treatment differences in the primary or key secondary endpoints across statin type or lipophilic/lipophobic category were observed. A similar lack of treatment difference was observed in LDL-C changes from baseline to one year. Therefore, the LDL-C changes and CV risk reduction in REDUCE-IT appear independent of the type of concomitant statin therapy. These data provide clinicians with additional insight regarding concomitant statin therapy considerations when prescribing icosapent ethyl and suggest there are important mechanisms of action for the substantial CV risk reduction observed with icosapent ethyl that are distinct from the LDL receptor pathway.

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): The study was funded by Amarin Pharma, Inc.

REDUCE-IT: accumulation of data across prespecified interim analyses to final results

Background

REDUCE-IT (Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial), an event-driven trial, randomized 8,179 statin-treated patients with elevated triglycerides (TGs) and increased cardiovascular (CV) risk to icosapent ethyl (IPE); pure, stable prescription eicosapentaenoic acid, 4g/day or placebo. 1,612 primary endpoint events (CV death, nonfatal myocardial infarction [MI], nonfatal stroke, coronary revascularization, or hospitalization for unstable angina) projected 90% power to detect 15% relative risk reduction (5% 2-sided alpha). The key secondary composite endpoint was CV death, nonfatal MI, or nonfatal stroke. An independent data and safety monitoring committee (DMC) performed prespecified interim analyses (IAs) at ∼60% (IA1 31 May 2016 data cutoff; 2.9 y median primary endpoint follow-up) and ∼80% (IA2 01 May 2017; 3.7 y) of events; final analysis included 1,606 events (06 Sep 2018; 4.9 y median study follow-up).

Purpose

Explore REDUCE-IT efficacy and safety across prespecified IAs for insight into progression of robustness and consistency of conclusions.

Methods

The interim statistical analysis plan guided study continuation decisions by a prespecified decision-making process, including assessment of safety, treatment arm performance, primary composite endpoint formal analyses, and informal robustness analyses, with no futility or efficacy stopping requirements. Prior to DMC IA study continuation decisions, the need for a mature dataset to support the robustness of final efficacy and safety findings was discussed. Sponsor, Steering Committee, and Clinical Endpoint Committee were blinded throughout.

Results

Primary and key secondary endpoints achieved statistical significance at IA1 and IA2 that persisted at final analyses (p-value below final adjusted 2-sided alpha of 0.0437); hazard ratios also remained consistent and similar robustness was observed across individual endpoint components; clarity of findings across endpoints and subgroups improved with more events. Stopping for overwhelming efficacy was discussed at each IA; prior to IA study continuation recommendations, the DMC considered historical examples of failed CV outcome studies for TG-lowering and mixed omega-3 therapies, reflected on the potential for overestimating final demonstrated benefit using incomplete data, and weighed societal impacts of fuller datasets relative to patient therapy access.

Conclusions

Consistent, potent efficacy emerged early and persisted across the two prespecified interim and final analyses. The mature dataset demonstrated highly statistically significant reductions in the primary (25%; p=0.00000001) and key secondary (26%; p=0.0000006) endpoints and allowed robust analyses to support overall efficacy and safety conclusions. Allowing the REDUCE-IT dataset to fully mature provided clinicians with robust, consistent, and reliable data upon which to base clinical decisions for IPE in CV risk reduction.

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): The study was funded by Amarin Pharma, Inc.

REDUCE-IT: total ischemic events reduced across the full range of baseline LDL cholesterol and other key subgroups

Background

REDUCE-IT (Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial), a study of 8,179 randomized statin-treated patients with elevated triglycerides (TG) and increased cardiovascular (CV) risk followed for a median of 4.9 years, demonstrated robust results. Icosapent ethyl (IPE), a pure and stable prescription form of eicosapentaenoic acid, 4g/day reduced both time-to-first and total primary endpoint ischemic events (CV death, nonfatal myocardial infarction [MI], nonfatal stroke, coronary revascularization, or hospitalization for unstable angina) by 25% (HR 0.75; 95% CI 0.68–0.83; p<0.0001) and 30% (rate ratio 0.70; 95% CI 0.62–0.78; p<0.0001), respectively. Similar substantial reductions in first and total key secondary endpoint ischemic events (composite of CV death, nonfatal MI, or nonfatal stroke) were also observed. Demographic and baseline disease characteristics were generally balanced across treatment groups. Time-to-first event analyses showed robust and generally consistent benefit across subgroups. Previous total event analyses by baseline TG demonstrated large, consistent, statistically significant reductions across tertiles, suggesting the CV benefit of IPE is tied primarily to non-TG factors.

Purpose

Further explore the extent to which IPE reduced total primary and key secondary events across prespecified baseline demographic, disease, treatment, and lipid/lipoprotein/inflammatory biomarker subgroups.

Methods

Total events across subgroups were assessed with the prespecified negative binomial regression method. Main outcomes were total (first and subsequent) primary and key secondary composite endpoint events.

Results

Median baseline LDL-C levels in ascending tertiles were 58, 76, and 96 mg/dL; there were large, significant relative reductions in total primary endpoint events with IPE across tertiles (35%, 28%, and 27%, respectively; interaction p=0.62), with parallel substantial absolute risk reductions. Similar, significant relative reductions of 33%, 28%, and 24% in total key secondary endpoint events were observed, along with substantial absolute risk reductions. Total events analyses of prespecified subgroups also demonstrated robust and generally consistent findings for the primary and key secondary composite endpoints.

Conclusion

REDUCE-IT demonstrated substantial reductions in first and total primary and key secondary endpoint ischemic events, with robust and generally consistent results across baseline TG and LDL-C levels, as well as other prespecified baseline biomarker, demographic, disease, and treatment subgroups. These analyses provide useful insights for clinicians considering the range of patients who may benefit from IPE therapy and suggest that mechanisms beyond the lipid/lipoprotein/inflammatory pathways tested, including mechanisms beyond the LDL receptor pathways, may contribute to the observed substantial reductions in total ischemic burden with IPE therapy.

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): The study was funded by Amarin Pharma, Inc.

A rapidly expanding Bose-Einstein condensate: an expanding universe in the lab

We study the dynamics of a supersonically expanding ring-shaped Bose-Einstein condensate both experimentally and theoretically. The expansion redshifts long-wavelength excitations, as in an expanding universe. After expansion, energy in the radial mode leads to the production of bulk topological excitations - solitons and vortices - driving the production of a large number of azimuthal phonons and, at late times, causing stochastic persistent currents. These complex nonlinear dynamics, fueled by the energy stored coherently in one mode, are reminiscent of a type of "preheating" that may have taken place at the end of inflation.

The effect of a perioperative ketamine infusion on the incidence of chronic postsurgical pain-a pilot study

Chronic postsurgical pain (CPSP) is a common and debilitating complication of major surgery. We undertook a pilot study at three hospitals to assess the feasibility of a proposed large multicentre placebo-controlled randomised trial of intravenous perioperative ketamine to reduce the incidence of CPSP. Ketamine, 0.5 mg/kg pre-incision, 0.25 mg/kg/hour intraoperatively and 0.1 mg/kg/hour for 24 hours, or placebo, was administered to 80 patients, recruited over a 15-month period, undergoing abdominal or thoracic surgery under general anaesthesia. The primary endpoint was CPSP in the area of the surgery reported at six-month telephone follow-up using a structured questionnaire. Fourteen patients (17.5%) reported CPSP (relative risk [95% confidence interval] if received ketamine 1.18 [0.70 to 1.98], P=0.56). Four patients in the treatment group and three in the control group reported ongoing analgesic use to treat CPSP and two patients in each group reported their worst pain in the previous 24 hours at ≥3/10 at six months. There were no significant differences in adverse event rates, quality of recovery scores, or cumulative morphine equivalents consumption in the first 72 hours. Numeric Rating Scale pain scores (median [interquartile range, IQR]) for average pain in the previous 24 hours among those patients reporting CPSP were 17.5 [0 to 40] /100 with no difference between treatment groups. A large (n=4,000 to 5,000) adequately powered multicentre trial is feasible using this population and methodology.

New limits on Planck scale Lorentz violation in QED

Constraints on possible Lorentz symmetry violation (LV) of order E/M(Planck) for electrons and photons in the framework of effective field theory (EFT) are discussed. Using (i) the report of polarized MeV emission from GRB021206 and (ii) the absence of vacuum Cerenkov radiation from synchrotron electrons in the Crab Nebula, we improve previous bounds by 10(-10) and 10(-2), respectively. We also show that the LV parameters for positrons and electrons are different, discuss electron helicity decay, and investigate how prior constraints are modified by the relations between LV parameters implied by EFT.

A strong astrophysical constraint on the violation of special relativity by quantum gravity

Special relativity asserts that physical phenomena appear the same to all unaccelerated observers. This is called Lorentz symmetry and relates long wavelengths to short ones: if the symmetry is exact it implies that space-time must look the same at all length scales. Several approaches to quantum gravity, however, suggest that there may be a microscopic structure of space-time that leads to a violation of Lorentz symmetry. This might arise because of the discreteness or non-commutivity of space-time, or through the action of extra dimensions. Here we determine a very strong constraint on a type of Lorentz violation that produces a maximum electron speed less than the speed of light. We use the observation of 100-MeV synchrotron radiation from the Crab nebula to improve the previous limit by a factor of 40 million, ruling out this type of Lorentz violation, and thereby providing an important constraint on theories of quantum gravity.

Volatile anesthetics give a false-positive reading in chemical agent monitors in the "H" mode

Chemical agent monitors (CAMs) are routinely used by the armed forces and emergency response teams of many countries for the detection of the vesicant sulfur mustard (HD) and the G series of organophosphate nerve agents. Ambient operating room isoflurane levels were found to produce strong positive signals in the "H" mode when the CAM was used to monitor the efficacy of decontamination procedures during routine surgical procedures on HD-poisoned animals requiring up to 8 hours of general anesthesia. Subsequent testing showed that isoflurane, as well as desflurane, sevoflurane, halothane and methoxyflurane, produce two ionization peaks in the CAM response. One of these peaks is interpreted by the CAM processing software as HD, resulting in a CAM "H" mode bar response. No interference was encountered with isoflurane, desflurane, and sevoflurane when the CAM was set to the "G" mode, although extremely high (nonclinical) concentrations of halothane and methoxyflurane yielded a weakly positive bar response. These findings have potentially serious ramifications for the medical management of patients resulting from terrorist, military, or chemical agent decommissioning activity when concomitant chemical injuries are also possible.

Effects of milk or water on lunch intake in preschool children

In Sweden, milk and milk products are important sources of daily energy intake but the role of milk with preschool lunch meals has been debated frequently and water is often alternatively given today. We studied the effects of milk or water on lunch energy intake. Water or milk alternatively was served in a controlled, within-subject design on 12 occasions to 36 children aged 4-6 years, and energy intake was analysed at an individual level in three typical preschool lunches with a varying degree of preference among the children. When milk was given with the meals, a mean additional energy intake of 17% (p<0.0001) was found. The pattern was similar among boys and girls and irrespective of the lunch dish served. However, for the least preferred dish (fish with potatoes) milk helped to increase the energy intake by 26%. Physical activity measured as MET units (energy expenditure/body weight), atmosphere at the table as registered by a three-graded scale, and meal duration did not differ with meals or milk/water. Milk with preschool lunch meals seems to be a significant source of energy to achieve nutritional goals for this group of children.

Testing the Uniform Needs Assessment Instrument for hospital discharge planning with older adults

The Uniform Needs Assessment Instrument (UNAI) was developed to systematically assess the continuing care needs of high-risk older adults in response to the 1986 Omnibus Budget Reconciliation Act. Based on previous studies, a revised UNAI was tested with 103 hospitalized older adults, comparing usual discharge planning with the UNAI. High interrater reliability was obtained. The UNAI had high (> or = 85%) sensitivity and specificity when comparing needs identification on the UNAI with subjects' reported needs at 10 to 14 days after discharge. Overall, the UNAI was more effective (sensitive and specific).

Stricture and pouchitis after ileal pouch-anal anastomosis

Ileal pouch-anal anastomosis is a surgical procedure used for the treatment of people with chronic ulcerative colitis and familial adenomatous polyposis. The surgery is intended to preserve anal sphincter function, but it carries a risk for certain complications, including pouchitis and anastomotic stricture. The purpose of this article is to review the clinical manifestations, causes, and treatment of anastomotic stricture and pouchitis after ileal pouch-anal anastomosis.

Standardized ET nursing database: imagine the possibilities

A national database of the components of ET nursing practice currently does not currently exist. Justification for ET nurse services requires hard data that demonstrate quality and cost-effectiveness of care. Lacking hard data, the value of the services provided by ET nurses remains difficult to quantify. The Nursing Minimum Data Set is the first step in building a nursing database. The purpose of this article is to familiarize ET nurses with the concepts of nursing information systems, the Nursing Minimum Data Set, and classification systems. Implications for ET nursing practice are also presented.

Modeling unemployment duration in a dependent competing risks framework: identification and estimation

Three Mixed Proportional Hazard models for estimation of unemployment duration when attrition is present are considered. The virtue of these models is that they take account of dependence between failure times in a multivariate failure time distribution context. However, identification in dependent competing risks models is not straightforward. We show that these models, independently derived, are special cases of a general frailty model. It is also demonstrated that the three models are identified by means of identification of the general model. An empirical example illustrates the approach to model dependent failure times.

Long-term treatment of hypercholesterolemia with dietary fiber

PURPOSE

To evaluate the hypocholesterolemic effects of long-term treatment (36 to 51 weeks) with a mixture of dietary fibers (guar gum, pectin, soy, pea, corn bran) administered twice a day.

PATIENTS AND METHODS

Fifty-nine subjects with moderate hypercholesterolemia who completed a 15-week, placebo-controlled study with the dietary fiber were treated for an additional 36 weeks with 20 g/day of fiber. Subjects were counseled and monitored on a National Cholesterol Education Program (NCEP) Step-One Diet before starting and during treatment. Analyses of changes in lipoprotein values during the additional 36 weeks of treatment took into account changes in weight, diet, and other variables that might have affected the response to treatment.

RESULTS

There were no significant effects on the levels of either triglycerides or high-density lipoprotein cholesterol (HDL-C). Levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) and the LDL/HDL ratio were significantly reduced during treatment. The mean percentage reductions from baseline after 51 weeks of treatment were approximately 5% for TC, 9% for LDL-C, and 11% for the LDL/HDL ratio. Changes were apparent after 3 weeks of treatment, with the maximum reductions occurring by the 15th week of treatment.

CONCLUSIONS

For subjects on a Step-One Diet who complied with the treatment regimen, the moderate cholesterol-lowering effects of the fiber persisted throughout the 36-to-51 week treatment period.

Sympathomimetic drug abuse masking an endogenous hyperadrenergic state, Graves' disease

Sympathomimetic drug use or abuse in a thyrotoxic individual can be clinically devastating as a result of enhanced cellular sensitivity to adrenergic stimulation. Thus, it is critical to recognize thyrotoxicosis in a patient with coexistent sympathomimetic drug abuse. This case report describes a patient with Graves' disease and severe hyperadrenergic symptomatology that was thought to result from sympathomimetic drug abuse.

Social support and suicide potential: preliminary findings for adolescent populations

The relationship between both the quantity and perceived quality of social support and suicidal risk was examined in a sample of 50 adolescents whose ages ranged from 16 to 20 years. A multiple regression analysis was performed, using scores from Cull and Gill's 1983 Suicide Probability Scale as the criterion measure along with the predictor variables of quantity and quality of experienced social support as measured by the 1983 Social Support Questionnaire of Sarason, Levine, Basham, and Sarason. Analysis showed the social support variables accounted for over 52% of the variance in suicide potential. The greatest proportion of the variance in suicide risk was attributable to the quality of the perceived social support. Adolescents at greater risk for suicide were significantly less satisfied with the quality of their social support.

Surgical correction of the snapping iliopsoas tendon

Eighteen patients with 20 symptomatic hips underwent lengthening of the iliopsoas tendon for persistent painful snapping of this "internal" variety of snapping hip. We referred to the pathologic, painful snapping of the iliopsoas in the deep anterior groin as the "internal" snapping hip. This is in contrast to the more common and better-known "external" snapping that involves the greater trochanter and its overlying soft tissues. The results of our iliopsoas lengthening procedure are presented here. Lengthening of the iliopsoas tendon was accomplished by step cutting of the tendinous portion of the iliopsoas. The pathoanatomy of this poorly understood symptom complex was described in 1984 paper from this institution and is reviewed here. Iliopsoas bursography demonstrated a sudden jerking movement of the iliopsoas tendon between the anterior inferior iliac spine and iliopectineal eminence, synchronous with the patient's pain and often accompanied by an audible snap. The average preoperative duration of symptoms was 2.9 years, and the average length of postoperative followup was 25 months. All patients, except one, had a marked reduction in the frequency of snapping after tendon lengthening, and 14 of 20 hips had no snapping postoperatively. Of the six patients who had recurrence of snapping, all but one stated that this occurred much less frequently and was much less painful compared to the preoperative state. Two hips required reoperation. Postoperatively, only three patients complained of subjective weakness, and most patients were unlimited in physical activity with return to activities such as competitive football, pole vaulting, and long-distance running.(ABSTRACT TRUNCATED AT 250 WORDS)