Transforming blood pressure control in primary care through a novel remote decision support strategy based on wearable blood pressure monitoring: The NEXTGEN-BP randomized trial protocol

BACKGROUND

Despite high blood pressure being the leading preventable risk factor for death, only 1 in 3 patients achieve target blood pressure control. Key contributors to this problem are clinical inertia and uncertainties in relying on clinic blood pressure measurements to make treatment decisions.

METHODS

The NEXTGEN-BP open-label, multicenter, randomized controlled trial will investigate the efficacy, safety, acceptability and cost-effectiveness of a wearable blood pressure monitor-based care strategy for the treatment of hypertension, compared to usual care, in lowering clinic blood pressure over 12 months. NEXTGEN-BP will enroll 600 adults with high blood pressure, treated with 0 to 2 antihypertensive medications. Participants attending primary care practices in Australia will be randomized 1:1 to the intervention of a wearable-based remote care strategy or to usual care. Participants in the intervention arm will undergo continuous blood pressure monitoring using a wrist-wearable cuffless device (Aktiia, Switzerland) and participate in 2 telehealth consultations with their primary care practitioner (general practitioner [GP]) at months 1 and 2. Antihypertensive medication will be up-titrated by the primary care practitioner at the time of telehealth consults should the percentage of daytime blood pressure at target over the past week be <90%, if clinically tolerated. Participants in the usual care arm will have primary care consultations according to usual practice. The primary outcome is the difference between intervention and control in change in clinic systolic blood pressure from baseline to 12 months. Secondary outcomes will be assessed at month 3 and month 12, and include acceptability to patients and practitioners, cost-effectiveness, safety, medication adherence and patient engagement.

CONCLUSIONS

NEXTGEN-BP will provide evidence for the effectiveness and safety of a new paradigm of wearable cuffless monitoring in the management of high blood pressure in primary care.

TRIAL REGISTRATION

ACTRN12622001583730.

Triple Therapy Prevention of Recurrent Intracerebral Disease Events Trial: Rationale, design and progress

BACKGROUND

Patients who suffer intracerebral hemorrhage (ICH) are at very high risk of recurrent ICH and other serious cardiovascular events. A single-pill combination (SPC) of blood pressure (BP) lowering drugs offers a potentially powerful but simple strategy to optimize secondary prevention.

OBJECTIVES

The Triple Therapy Prevention of Recurrent Intracerebral Disease Events Trial (TRIDENT) aims to determine the effects of a novel SPC "Triple Pill," three generic antihypertensive drugs with demonstrated efficacy and complementary mechanisms of action at half standard dose (telmisartan 20 mg, amlodipine 2.5 mg, and indapamide 1.25 mg), with placebo for the prevention of recurrent stroke, cardiovascular events, and cognitive impairment after ICH.

DESIGN

An international, double-blind, placebo-controlled, randomized trial in adults with ICH and mild-moderate hypertension (systolic BP: 130-160 mmHg), who are not taking any Triple Pill component drug at greater than half-dose. A total of 1500 randomized patients provide 90% power to detect a hazard ratio of 0.5, over an average follow-up of 3 years, according to a total primary event rate (any stroke) of 12% in the control arm and other assumptions. Secondary outcomes include recurrent ICH, cardiovascular events, and safety.

RESULTS

Recruitment started 28 September 2017. Up to 31 October 2021, 821 patients were randomized at 54 active sites in 10 countries. Triple Pill adherence after 30 months is 86%. The required sample size should be achieved by 2024.

CONCLUSION

Low-dose Triple Pill BP lowering could improve long-term outcome from ICH.

Continuous Positive Airway Pressure Treatment, Glycemia, and Diabetes Risk in Obstructive Sleep Apnea and Comorbid Cardiovascular Disease

OBJECTIVE

Despite evidence of a relationship among obstructive sleep apnea (OSA), metabolic dysregulation, and diabetes, it is uncertain whether OSA treatment can improve metabolic parameters. We sought to determine effects of long-term continuous positive airway pressure (CPAP) treatment on glycemic control and diabetes risk in patients with cardiovascular disease (CVD) and OSA.

RESEARCH DESIGN AND METHODS

Blood, medical history, and personal data were collected in a substudy of 888 participants in the Sleep Apnea cardioVascular Endpoints (SAVE) trial in which patients with OSA and stable CVD were randomized to receive CPAP plus usual care, or usual care alone. Serum glucose and glycated hemoglobin A_1c (HbA_1c) were measured at baseline, 6 months, and 2 and 4 years and incident diabetes diagnoses recorded.

RESULTS

Median follow-up was 4.3 years. In those with preexisting diabetes (n = 274), there was no significant difference between the CPAP and usual care groups in serum glucose, HbA_1c, or antidiabetic medications during follow-up. There were also no significant between-group differences in participants with prediabetes (n = 452) or new diagnoses of diabetes. Interaction testing suggested that women with diabetes did poorly in the usual care group, while their counterparts on CPAP therapy remained stable.

CONCLUSIONS

Among patients with established CVD and OSA, we found no evidence that CPAP therapy over several years affects glycemic control in those with diabetes or prediabetes or diabetes risk over standard-of-care treatment. The potential differential effect according to sex deserves further investigation.

Predictors of long-term adherence to continuous positive airway pressure in patients with obstructive sleep apnea and cardiovascular disease

Study Objectives

Poor adherence to continuous positive airway pressure (CPAP) commonly affects therapeutic response in obstructive sleep apnea (OSA). We aimed to determine predictors of adherence to CPAP among participants of the Sleep Apnea and cardioVascular Endpoints (SAVE) trial.

Methods

SAVE was an international, randomized, open trial of CPAP plus usual care versus usual care (UC) alone in participants (45–75 years) with co-occurring moderate-to-severe OSA (≥12 episodes/h of ≥4% oxygen desaturation) and established cardiovascular (CV) disease. Baseline sociodemographic, health and lifestyle factors, OSA symptoms, and 1-month change in daytime sleepiness, as well as CPAP side effects and adherence (during sham screening, titration week, and in the first month), were entered in univariate linear regression analyses to identify predictors of CPAP adherence at 24 months. Variables with p <0.2 were assessed for inclusion in a multivariate linear mixed model with country, age, and sex included a priori and site as a random effect.

Results

Significant univariate predictors of adherence at 24 months in 1,121 participants included: early adherence measures, improvement in daytime sleepiness at 1 month, fixed CPAP pressure, some measures of OSA severity, cardiovascular disease history, breathing pauses, and very loud snoring. While observed adherence varied between countries, adherence during sham screening, initial titration, and the first month of treatment retained independent predictive value in the multivariate model along with fixed CPAP pressure and very loud snoring.

Conclusions

Early CPAP adherence had the greatest predictive value for identifying those at highest risk of non-adherence to long-term CPAP therapy.

Clinical Trial Registration

SAVE is registered with clinicaltrials.gov (NCT00738179).

Effect of Obstructive Sleep Apnea Treatment on Renal Function in Patients with Cardiovascular Disease

RATIONALE

Obstructive sleep apnea (OSA) is associated with impaired renal function, but uncertainty exists over whether OSA treatment can influence renal outcomes.

OBJECTIVES

To determine the effects of continuous positive airway pressure (CPAP) on renal function in subjects with coexisting OSA and cardiovascular disease.

METHODS

This was a substudy of the international SAVE (Sleep Apnea Cardiovascular Endpoints) trial, in which 2,717 patients with moderate to severe OSA and established coronary or cerebrovascular disease were randomized to receive either CPAP plus usual care or usual care alone. Renal function and adverse renal events were compared between the CPAP (n = 102) and usual care (n = 98) groups. Glomerular filtration rate was estimated at randomization and at the end of follow-up, and the urinary albumin-to-creatinine ratio was measured at study exit.

MEASUREMENTS AND MAIN RESULTS

In 200 substudy participants (mean age, 64 yr; median, 4% oxygen desaturation index; 20 events/h; mean estimated glomerular filtration rate at baseline, 82 ml/min/1.73 m²), the median (interquartile range) changes in estimated glomerular filtration rate (ml/min/1.73 m²/yr) were -1.64 (-3.45 to -0.740) in the CPAP group and -2.30 (-4.53 to -0.71) in the usual care group (P = 0.21) after a median of 4.4 years. There were no between-group differences in end-of-study urinary albumin-to-creatinine ratio or in the occurrence of serious renal or urinary adverse events during the trial. The level of CPAP adherence did not influence the findings.

CONCLUSIONS

CPAP treatment of OSA in patients with cardiovascular disease does not alter renal function or the occurrence of renal adverse events. Clinical trial registered with www.clinicaltrials.gov (NCT00738179).

Operational Failures Detected by Frontline Acute Care Nurses

Frontline nurses encounter operational failures (OFs), or breakdowns in system processes, that hinder care, erode quality, and threaten patient safety. Previous research has relied on external observers to identify OFs; nurses have been passive participants in the identification of system failures that impede their ability to deliver safe and effective care. To better understand frontline nurses' direct experiences with OFs in hospitals, we conducted a multi-site study within a national research network to describe the rate and categories of OFs detected by nurses as they provided direct patient care. Data were collected by 774 nurses working in 67 adult and pediatric medical-surgical units in 23 hospitals. Nurses systematically recorded data about OFs encountered during 10 work shifts over a 20-day period. In total, nurses reported 27,298 OFs over 4,497 shifts, a rate of 6.07 OFs per shift. The highest rate of failures occurred in the category of Equipment/Supplies, and the lowest rate occurred in the category of Physical Unit/Layout. No differences in OF rate were detected based on hospital size, teaching status, or unit type. Given the scale of this study, we conclude that OFs are frequent and varied across system processes, and that organizations may readily obtain crucial information about OFs from frontline nurses. Nurses' detection of OFs could provide organizations with rich, real-time information about system operations to improve organizational reliability. © 2017 Wiley Periodicals, Inc.

Perception of airway narrowing during reduction of inhaled corticosteroids and asthma exacerbation

BACKGROUND

The perception of airway narrowing is reduced in subjects with severe asthma and may be related to the severity of airway inflammation. A study was undertaken to determine if the perception of airway narrowing changes during the reduction of inhaled corticosteroid (ICS) dose or during an asthma exacerbation.

METHODS

Forty two asthmatic subjects with well controlled asthma had their daily ICS dose halved every 2 months until they were weaned off ICS or they developed an exacerbation. Perception was measured at baseline and at monthly intervals during bronchial challenge with mannitol as the slope and intercept of the regression of the Borg score and percentage fall in forced expiratory volume in 1 second (FEV(1)), and as the Borg score at 20% fall in FEV(1) (PS(20)FEV(1)). Sputum was collected for measurement of inflammatory cell numbers.

RESULTS

In 33 subjects who successfully halved their ICS dose without exacerbation there were significant reductions in slope (p = 0.01), intercept (p = 0.01), and PS(20)FEV(1) (p = 0.003). Sputum eosinophils and airway hyperresponsiveness increased significantly but, in 14 subjects from whom sputum was obtained, changes in eosinophils were not correlated with changes in perception. Change in airway hyperresponsiveness correlated with change in PS(20)FEV(1) (r = -0.40, p = 0.025). In 27 subjects who developed an exacerbation, slope decreased (p = 0.02) and intercept increased (p = 0.01) compared with the visit before the exacerbation. Changes in intercept correlated with changes in resting FEV(1) (r = -0.57, p = 0.002).

CONCLUSIONS

Perception of airway narrowing decreases during ICS dose reduction and decreases further during a mild asthma exacerbation. These changes are related to concurrent changes in airway hyperresponsiveness and resting lung function. The effect of changes in airway inflammation on perception is unclear.

Calcium influx-independent depression of transmitter release by 5-HT at lamprey spinal cord synapses

1. The mechanisms by which 5-hydroxytryptamine (5-HT) depresses transmitter release from lamprey reticulospinal axons were investigated. These axons make glutamatergic synapses onto spinal ventral horn neurons. 5-HT reduces release at these synapses, yet the mechanisms remain unclear. 2. Excitatory postsynaptic currents (EPSCs) evoked by stimulation of reticulospinal axons were recorded in ventral horn neurons. 5-HT depressed the EPSCs in a dose-dependent manner with an apparent Km of 2.3 microM. 3. To examine the presynaptic effect of 5-HT, electrophysiological and optical recordings were made from presynaptic axons. Action potentials evoked Ca(2+) transients in the axons loaded with a Ca(2+)-sensitive dye. 5-HT slightly reduced the Ca(2+) transient. 4. A third-power relationship between Ca(2+) entry and transmitter release was determined. However, presynaptic Ca(2+) currents were unaffected by 5-HT. 5. Further, in the presence of a K(+) channel blocker, 4-aminopyridine (4-AP), 5-HT left unaltered the presynaptic Ca(2+) transient, ruling out the possibility of its direct action on presynaptic Ca(2+) current. 5-HT activated a 4-AP-sensitive current with a reversal potential of -95 mV in these axons. 6. The basal Ca(2+) concentration did not affect 5-HT-mediated inhibition of release. Although 5-HT caused a subtle reduction in resting axonal [Ca(2+)]i, synaptic responses recorded during enhanced resting [Ca(2+)]i, by giving stimulus trains, were equally depressed by 5-HT. 7. 5-HT reduced the frequency of TTX-insensitive spontaneous EPSCs at these synapses, but had no effect on their amplitude. We propose a mechanism of inhibition for transmitter release by 5-HT that is independent of presynaptic Ca(2+) entry.

Predictive markers of asthma exacerbation during stepwise dose reduction of inhaled corticosteroids

To determine predictors for failed reduction of inhaled corticosteroids (ICS), in 50 subjects with well-controlled asthma (age 43.7 [18-69]; 22 males) taking a median dose of 1,000 microg ICS/d (100-3,600 microg/d), ICS were halved every 8 wk. Airway hyperresponsiveness (AHR) to a bronchial provocation test (BPT) with histamine was measured at baseline. AHR to BPT with mannitol, spirometry, exhaled nitric oxide (eNO), and, in 31 subjects, sputum inflammatory cells were measured at baseline and at monthly intervals. Thirty-nine subjects suffered an asthma exacerbation. Seven subjects were successfully weaned off ICS. Using a Kaplan- Meier survival analysis, the significant predictors of a failure of ICS reduction were being hyperresponsive to both histamine and mannitol at baseline (p = 0.039), and being hyperresponsive to mannitol during the dose-reduction phase of the study (p = 0.02). Subjects older than 40 yr of age tended to be at greater risk of ICS reduction failure (p = 0.059). Response to mannitol and percentage sputum eosinophils were significantly greater before a failed ICS reduction than before the last successful ICS reduction, whereas there were no significant differences in symptoms, spirometry, or eNO. These findings suggest that documentation of patient's AHR or sputum eosinophils may be useful in guiding the reduction of ICS doses.

Nedocromil sodium inhibits responsiveness to inhaled mannitol in asthmatic subjects

Nedocromil sodium inhibits the response to exercise-induced asthma (EIA). Mannitol given as a powder by inhalation is an osmotic stimulus that identifies EIA. We studied the acute effect of nedocromil on airway responsiveness to mannitol in 24 asthmatic subjects. After a control day, nedocromil (8 mg) or its placebo was administered randomized, double blind, 10 min before a challenge with progressively increasing doses of mannitol. Nedocromil inhibited the response to mannitol and there was a significant increase in the dose of mannitol required to cause a 15% reduction in FEV(1) (PD(15)) after nedocromil 409 (316,503) mg compared with placebo 156 (106,229) mg (p < 0.001). In the presence of nedocromil 12 subjects no longer recorded a 15% decrease in FEV(1) in response to mannitol. The remaining 12 required a significantly greater dose of mannitol to achieve a 15% decrease in FEV(1) after nedocromil. Following nedocromil, a plateau in responsiveness to mannitol was observed in 14 subjects. Nedocromil significantly inhibits the responsiveness to inhaled mannitol in asthmatic subjects.

Diffusible, nonfibrillar ligands derived from Abeta1-42 are potent central nervous system neurotoxins

Abeta1-42 is a self-associating peptide whose neurotoxic derivatives are thought to play a role in Alzheimer's pathogenesis. Neurotoxicity of amyloid beta protein (Abeta) has been attributed to its fibrillar forms, but experiments presented here characterize neurotoxins that assemble when fibril formation is inhibited. These neurotoxins comprise small diffusible Abeta oligomers (referred to as ADDLs, for Abeta-derived diffusible ligands), which were found to kill mature neurons in organotypic central nervous system cultures at nanomolar concentrations. At cell surfaces, ADDLs bound to trypsin-sensitive sites and surface-derived tryptic peptides blocked binding and afforded neuroprotection. Germ-line knockout of Fyn, a protein tyrosine kinase linked to apoptosis and elevated in Alzheimer's disease, also was neuroprotective. Remarkably, neurological dysfunction evoked by ADDLs occurred well in advance of cellular degeneration. Without lag, and despite retention of evoked action potentials, ADDLs inhibited hippocampal long-term potentiation, indicating an immediate impact on signal transduction. We hypothesize that impaired synaptic plasticity and associated memory dysfunction during early stage Alzheimer's disease and severe cellular degeneration and dementia during end stage could be caused by the biphasic impact of Abeta-derived diffusible ligands acting upon particular neural signal transduction pathways.

Protecting fibrinogen with rutin during UVC irradiation for viral inactivation

Fibrinogen solutions were irradiated with UVC (254 nm) to inactivate contaminating viruses. In order to protect fibrinogen during UVC irradiation, 0.5 mM rutin was added prior to UVC exposure and subsequently removed during processing. Viral kill by 0.1 J/cm2 UVC resulted in the following inactivation values (log 10): non-lipid-enveloped viruses: Parvo > or = 5.5; encephalomyocarditis virus > or = 6.5; hepatitis A virus > or = 6.5: lipid-enveloped viruses: human immunodeficiency virus > or = 5.7; vesicular stomatitis virus > or = 5.7. Fibrinogen irradiated with 0.5 mM rutin did not significantly differ from unirradiated material in terms of clot time and breaking strength. In the absence of rutin, UVC irradiation of fibrinogen at similar fluence led to loss of solubility, increased clot time and the cleavage of fibrino-peptides that reacted with dinitrophenyl hydrazine as a test for ketonic carbonyl groups. High-performance liquid chromatography and mass spectrometry data showed that rutin exposed to UVC formed numerous breakdown, oxidation and combinational products. Experiments with 3H-rutin showed that after UVC irradiation, subsequent processing by a C18 resin and alcohol precipitation removed > 99% rutin, representing < 10 ppm rutin in the final fibrinogen preparations. Residual 3H-rutin was not covalently bonded to the fibrinogen. Immunochemical studies with rabbit antisera to UVC irradiated (with rutin) fibrinogen showed the absence of neoimmungens. By all measures, rutin prevents fibrinogen degradation during virucidal UVC irradiation.

Tracking quality assurance activity. A PC-based computerized system

The difficulty of gathering together, organizing, and collating hospital quality assurance information is a common problem for hospital quality assurance departments. Trying to assemble and compare quality data, appearing in multiple locations, from multiple sources, across a time-line often measured in months, may prevent recognition of care patterns indicative of real problems. We describe our development of PC- based software to help deal with collecting and col lating information from the medical records depart ment, infection control, medical audit committees, the medical staff, the nursing units, peer review organi zation data, and multiple other scattered sources. This paper explains how the quality monitors were se lected and the types of statistical reports that such software can generate.

Metabolic requirements for maintenance of the chlortetracycline-labeled pool of membrane-bound calcium in human neutrophils

Human neutrophils labeled with chlortetracycline (CTC), commonly used as a probe of membrane-bound calcium, release lysosomal enzymes and exhibit a rapid decrease in fluorescence when exposed to the chemotactic peptide fMet-Leu-Phe or the lectin Con A. This decrease has been attributed to the release of calcium from a membrane-associated "trigger pool." The nature of this putative pool has been further characterized by examining the effects of various inhibitors on the CTC fluorescence response and lysosomal enzyme release from stimulated neutrophils. These agents included inhibitors of glycolysis (2-deoxyglucose and iodoacetate), an uncoupler of oxidative- phosphorylation (KCN), and a sulfhydryl inhibitor (N-ethylmaleimide). Resting neutrophils labelled with CTC demonstrated an enhanced decay of baseline fluorescence when exposed to 2-deoxyglucose or iodoacetate. This suggested that the pool of membrane-bound calcium labelled by this probe was maintained by glycolytic metabolism. Furthermore, 2-deoxyglucose and iodoacetate inhibited both the stimulated decrease in CTC fluorescence and lysosomal enzyme release induced by fMet-Leu-Phe and Con A in a time-dependent manner. KCN did not inhibit either response to stimulation, but did retard the recovery of CTC fluorescence observed when fMet-Leu-Phe was used as the stimulus. High concentrations of N-ethylmaleimide (100 microM) completely inhibited both the CTC fluorescence response and lysosomal enzyme release almost immediately; low concentrations of N-ethylmaleimide (30 microM) inhibited lysosomal enzyme release in a time-dependent manner without significantly affecting changes in CTC fluorescence. These results are consistent with the hypothesis that CTC serves as a probe of membrane-bound "trigger" calcium, the release of which is dependent upon intact glycolysis and is a requirement for lysosomal enzyme release.