The malarial blood transcriptome: translational applications.

The blood transcriptome of malaria patients has been used extensively to elucidate the pathophysiological mechanisms and host immune responses to disease, identify candidate diagnostic and prognostic biomarkers, and reveal new therapeutic targets for drug discovery. This review gives a high-level overview of the three main translational applications of these studies (diagnostics, prognostics, and therapeutics) by summarising recent literature and outlining the main limitations and future directions of each application. It highlights the need for consistent and accurate definitions of disease states and subject groups and discusses how prognostic studies must distinguish clearly between analyses that attempt to predict future disease states and those which attempt to discriminate between current disease states (classification). Lastly it examines how many promising therapeutics fail due to the choice of imperfect animal models for pre-clinical testing and lack of appropriate validation studies in humans, and how future transcriptional studies may be utilised to overcome some of these limitations.

The effect of adjusting LDL-cholesterol for Lp(a)-cholesterol on the diagnosis of familial hypercholesterolaemia.

BACKGROUND: Familial hypercholesterolaemia (FH) diagnostic tools help prioritise patients for genetic testing and include LDL-C estimates commonly calculated using the Friedewald equation. However, cholesterol contributions from lipoprotein(a) (Lp(a)) can overestimate 'true' LDL-C, leading to potentially inappropriate clinical FH diagnosis. OBJECTIVE: To assess how adjusting LDL-C for Lp(a)-cholesterol affects FH diagnoses using Simon Broome (SB) and Dutch Lipid Clinic Network (DLCN) criteria. METHODS: Adults referred to a tertiary lipid clinic in London, UK were included if they had undergone FH genetic testing based on SB or DLCN criteria. LDL-C was adjusted for Lp(a)-cholesterol using estimated cholesterol contents of 17.3%, 30% and 45%, and the effects of these adjustments on reclassification to 'unlikely' FH and diagnostic accuracy were determined. RESULTS: Depending on the estimated cholesterol content applied, LDL-C adjustment reclassified 8-23% and 6-17% of patients to 'unlikely' FH using SB and DLCN criteria, respectively. The highest reclassification rates were observed following 45% adjustment in mutation-negative patients with higher Lp(a) levels. This led to an improvement in diagnostic accuracy (46% to 57% with SB, and 32% to 44% with DLCN following 45% adjustment) through increased specificity. However all adjustment factors led to erroneous reclassification of mutation-positive patients to 'unlikely' FH. CONCLUSION: LDL-C adjustment for Lp(a)-cholesterol improves the accuracy of clinical FH diagnostic tools. Adopting this approach would reduce unnecessary genetic testing but also incorrectly reclassify mutation-positive patients. Health economic analysis is needed to balance the risks of over- and under-diagnosis before LDL-C adjustments for Lp(a) can be recommended.

The effect of 50% oxygen on PtCO2 in patients with stable COPD, bronchiectasis, and neuromuscular disease or kyphoscoliosis: randomised cross-over trials.

BACKGROUND: High-concentration oxygen therapy causes increased arterial partial pressure of carbon dioxide (PaCO2) in patients with COPD, asthma, pneumonia, obesity and acute lung injury. The objective of these studies was to investigate whether this physiological response to oxygen therapy occurs in stable patients with neuromuscular disease or kyphoscoliosis, and bronchiectasis. METHODS: Three randomised cross-over trials recruited stable patients with neuromuscular disease or kyphoscoliosis (n = 20), bronchiectasis (n = 24), and COPD (n = 24). Participants were randomised to receive 50% oxygen and 21% oxygen (air), each for 30 min, in randomly assigned order. The primary outcome was transcutaneous partial pressure of carbon dioxide (PtCO2) at 30 min. The primary analysis was a mixed linear model. RESULTS: Sixty six of the 68 participants had baseline PtCO2 values < 45 mmHg. The intervention baseline adjusted PtCO2 difference (95% CI) between oxygen and room air after 30 min was 0.2 mmHg (- 0.4 to 0.9), P = 0.40; 0.5 mmHg (- 0.2 to 1.2), P = 0.18; and 1.3 mmHg (0.7 to 1.8), P < 0.001, in the neuromuscular/kyphoscoliosis, bronchiectasis and COPD participants respectively. CONCLUSIONS: The small increase in PtCO2 in the stable COPD patients with high-concentration oxygen therapy contrasts with the marked increases in PaCO2 seen in the setting of acute exacerbations of COPD. This suggests that the model of studying the effects of high-concentration oxygen therapy in patients with stable respiratory disease is not generalisable to the use of oxygen therapy in the acute clinical setting. Appropriate studies of high-concentration compared to titrated oxygen in acute clinical settings are needed to determine if there is a risk of oxygen-induced hypercapnia in patients with neuromuscular disease, kyphoscoliosis or bronchiectasis. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12615000970549 Registered 16/9/15, ACTRN12615000971538 Registered 16/9/15 and ACTRN12615001056583 Registered 7/10/15.

Predictive value of blood eosinophils and exhaled nitric oxide in adults with mild asthma: a prespecified subgroup analysis of an open-label, parallel-group, randomised controlled trial.

BACKGROUND: Whether blood eosinophil counts and exhaled nitric oxide (FeNO) are associated with important outcomes in mild asthma is unclear. In this prespecified subgroup analysis of a previously published open-label clinical trial, we aimed to assess associations between blood eosinophil counts and FeNO with outcomes and response to asthma treatment. METHODS: In the previously reported 52-week, open-label, randomised controlled trial, people with mild asthma receiving only ß agonist reliever inhalers were enrolled at one of 16 clinical trials units in New Zealand, the UK, Italy, or Australia. Eligible participants were randomly assigned (1:1:1, stratified by country), to receive inhalers to take as-needed salbutamol (two inhalations of 100 µg in a pressurised metered dose inhaler), maintenance budesonide (200 µg twice per day by inhaler) plus as-needed salbutamol (two inhalations of 100 µg), or as-needed budesonide-formoterol (one inhalation of 200 µg budesonide and 6µg formoterol by inhaler). The primary outcome was the annual rates of asthma exacerbations per patient, and in this prespecified subgroup analysis, we assessed whether annual exacerbation rates in each treatment group were significantly different depending on levels of blood eosinophil count, FeNO, or a composite score of both. Analyses were done for patients with available biomarker measurements The study was registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12615000999538. FINDINGS: 675 participants were enrolled between March 17, 2016, and Aug 29, 2017, of whom 656 had results for blood eosinophil analysis and 668 had results for FeNO. Of the patients who received as-needed salbutamol, the proportion of patients having a severe exacerbation increased progressively with increasing blood eosinophil count (two [4%] of 49 participants with <0·15 × 109/L, six [6%] of 93 with 0·15 to <0·3 × 109/L, and 15 [19%] of 77 with ≥0·3 × 109/L; p=0·014). There were no significant interactions between blood eosinophil count or FeNO level and the effect of as-needed budesonide-formoterol compared with as-needed salbutamol for either exacerbations or severe exacerbations. However, there were significant interactions between blood eosinophil count subgroups and the effect of maintenance budesonide plus as-needed salbutamol compared with as-needed salbutamol, both for exacerbations (p=0·0006) and severe exacerbations (p=0·0007). Maintenance budesonide plus as-needed salbutamol was more effective than as-needed salbutamol in patients with blood eosinophil counts of 0·3 × 109/L or more, both for exacerbations (rate ratio 0·13 [95% CI 0·05-0·33]) and severe exacerbations (risk odds ratio 0·11 [0·03-0·45]). This difference was not seen for blood eosinophil counts of less than 0·15 × 109/L (1·15 [0·51-1·28] for exacerbations and 5·72 [0·97-33·60] for severe exacerbations). There was no consistent interaction between treatment response and FeNO or the composite score. INTERPRETATION: In patients with mild asthma, the effects of as-needed budesonide-formoterol on exacerbations are independent of biomarker profile, whereas the benefits of maintenance inhaled budesonide are greater in patients with high blood eosinophil counts than in patients with low counts. FUNDING: AstraZeneca, Health Research Council of New Zealand.

Controlled Trial of Budesonide-Formoterol as Needed for Mild Asthma.

BACKGROUND: In double-blind, placebo-controlled trials, budesonide-formoterol used on an as-needed basis resulted in a lower risk of severe exacerbation of asthma than as-needed use of a short-acting ß2-agonist (SABA); the risk was similar to that of budesonide maintenance therapy plus as-needed SABA. The availability of data from clinical trials designed to better reflect clinical practice would be beneficial. METHODS: We conducted a 52-week, randomized, open-label, parallel-group, controlled trial involving adults with mild asthma. Patients were randomly assigned to one of three treatment groups: albuterol (100 µg, two inhalations from a pressurized metered-dose inhaler as needed for asthma symptoms) (albuterol group); budesonide (200 µg, one inhalation through a Turbuhaler twice daily) plus as-needed albuterol (budesonide maintenance group); or budesonide-formoterol (200 µg of budesonide and 6 µg of formoterol, one inhalation through a Turbuhaler as needed) (budesonide-formoterol group). Electronic monitoring of inhalers was used to measure medication use. The primary outcome was the annualized rate of asthma exacerbations. RESULTS: The analysis included 668 of 675 patients who underwent randomization. The annualized exacerbation rate in the budesonide-formoterol group was lower than that in the albuterol group (absolute rate, 0.195 vs. 0.400; relative rate, 0.49; 95% confidence interval [CI], 0.33 to 0.72; P<0.001) and did not differ significantly from the rate in the budesonide maintenance group (absolute rate, 0.195 in the budesonide-formoterol group vs. 0.175 in the budesonide maintenance group; relative rate, 1.12; 95% CI, 0.70 to 1.79; P = 0.65). The number of severe exacerbations was lower in the budesonide-formoterol group than in both the albuterol group (9 vs. 23; relative risk, 0.40; 95% CI, 0.18 to 0.86) and the budesonide maintenance group (9 vs. 21; relative risk, 0.44; 95% CI, 0.20 to 0.96). The mean (±SD) dose of inhaled budesonide was 107±109 µg per day in the budesonide-formoterol group and 222±113 µg per day in the budesonide maintenance group. The incidence and type of adverse events reported were consistent with those in previous trials and with reports in clinical use. CONCLUSIONS: In an open-label trial involving adults with mild asthma, budesonide-formoterol used as needed was superior to albuterol used as needed for the prevention of asthma exacerbations. (Funded by AstraZeneca and the Health Research Council of New Zealand; Novel START Australian New Zealand Clinical Trials Registry number, ACTRN12615000999538.).

Change in biomarkers of type-2 inflammation following severe exacerbations of asthma.

We investigated the time course of change of type-2 asthma biomarkers after a severe asthma exacerbation. Blood eosinophils were lowest immediately after treatment was initiated (0.07 vs 0.33×109/L, p<0.001) while serum IgE levels were at their highest (339 vs 249 U/L, p<0.001). Fractional exhaled Nitric Oxide levels were lowest 2 weeks after treatment (23 vs 33 ppb, p=0.06) and serum periostin levels were lowest 1 week after treatment (45·9 vs 50·9 ng/mL, p<0.001). A delay of 4-8 weeks following a severe exacerbation is required if these biomarkers are used to guide the ongoing management of patients with asthma. TRIAL REGISTRATION NUMBER: Post-results; The Australia New Zealand Trial Registry, >ACTRN12614000443695.

Effect of active temperature management on mortality in intensive care unit patients.

OBJECTIVE: To evaluate the effect of active temperature management on mortality, intensive care unit (ICU) and hospital length of stay, as well as the relative efficacy of antipyretic medications and physical cooling devices for achieving reductions in temperature in critically ill adults. DESIGN, SETTING AND PARTICIPANTS: Systematic review and meta-analysis of randomised controlled trials (RCTs) investigating treatments administered to febrile patients in order to reduce body temperature. Fifteen studies reporting results from 13 RCTs met our eligibility criteria. INTERVENTIONS: Treatments administered to reduce body temperature were defined as physical cooling, nonsteroidal anti-inflammatory drugs, paracetamol, or any combination of these. MAIN OUTCOME MEASURES: The primary outcome variable was all-cause mortality at the longest time point after randomisation. Secondary outcomes were ICU and hospital length of stay, and body temperature 12 hours after randomisation. RESULTS: Active temperature control had no statistically significant association with mortality (odds ratio, 1.01; 95% confidence interval [CI], 0.81-1.28; P = 0.95, for fixed effects). There was no statistically significant association between active temperature management and ICU or hospital length of stay. Active temperature management was associated with a statistically significant reduction in temperature. The fixed effects estimate for the active minus control treatment for pharmaceutical management was -0.62C (95% CI, -0.72C to -0.51C; P < 0.001) and for physical cooling was -1.59C (95% CI, -1.82C to -1.35C; P < 0.001). CONCLUSIONS: Active temperature management neither increased nor decreased mortality risk in critically ill adults. When the therapeutic goal is to reduce body temperature, physical cooling approaches may be more effective than pharmacological measures in critically ill adults.

Outcomes of 23- and 24-weeks gestation infants in Wellington, New Zealand: A single centre experience.

Optimal perinatal care of infants born less than 24 weeks gestation remains contentious due to uncertainty about the long-term neurodevelopment of resuscitated infants. Our aim was to determine the short-term mortality and major morbidity outcomes from a cohort of inborn infants born at 23 and 24 weeks gestation and to assess if these parameters differed significantly between infants born at 23 vs. 24 weeks gestation. We report survival rates at 2-year follow-up of 22/38 (58%) at 23 weeks gestation and 36/60 (60%) at 24 weeks gestation. Neuroanatomical injury at the time of discharge (IVH ≥ Grade 3 and/or PVL) occurred in in 3/23 (13%) and 1/40 (3%) of surviving 23 and 24 weeks gestation infants respectively. Rates of disability at 2 years corrected postnatal age were not different between infants born at 23 and 24 weeks gestation. We show evidence that with maximal perinatal care in a tertiary setting it is possible to achieve comparable rates of survival free of significant neuroanatomical injury or severe disability at age 2 in infants born at 23-week and 24-weeks gestation.

Trends in international asthma mortality: analysis of data from the WHO Mortality Database from 46 countries (1993-2012).

BACKGROUND: International time trends in asthma mortality have been strongly affected by changes in management and in particular drug treatments. However, little is known about how asthma mortality has changed over the past decade. In this study, we assessed these international trends. METHODS: We collated age-standardised country-specific asthma mortality rates in the 5-34 year age group from the online WHO Mortality Database for 46 countries. To be included in the analysis, we specified that a country must have 10 years of complete data in the WHO Mortality Database between 1993 and 2012. In the absence of consistent and accurate asthma prevalence and prescribing data, we chose to use a locally weighted scatter plot smoother (LOESS) curve, weighted by the individual country population in the 5-34-year age group to show the global trends in asthma mortality rates with time. FINDINGS: Of the 46 countries included in the analysis of asthma mortality, 36 were high-income countries, and 10 were middle-income countries. The LOESS estimate of the global asthma mortality rate was 0·44 deaths per 100 000 people (90% CI 0·39-0·48) in 1993 and 0·19 deaths per 100 000 people (0·18-0·21) in 2006. Despite apparent further reductions in some countries and regions of the world, there was no appreciable change in global asthma mortality rates from 2006 through to 2012, when the LOESS estimate was also 0·19 deaths per 100 000 people (0·16-0·21). INTERPRETATION: The trend for reduction in global asthma mortality observed since the late 1980s might have stalled, with no appreciable difference in a smoothed LOESS curve of asthma mortality from 2006 to 2012. Although better implementation of established management strategies that have been shown to reduce mortality risk is needed, to achieve a further substantive reduction in global asthma mortality novel strategies will also be required. FUNDING: The Medical Research Institute of New Zealand, which is supported by Health Research Council of New Zealand Independent Research Organisation.

Beta-agonist overuse and delay in obtaining medical review in high risk asthma: a secondary analysis of data from a randomised controlled trial.

Asthma mortality surveys report delays in seeking medical review and overuse of beta-agonist therapy as factors contributing to a fatal outcome. However, the strength of these associations is limited because many asthma deaths are unwitnessed. We undertook a secondary analysis of data from a 24-week randomised controlled trial of 303 patients with high-risk asthma, randomised to combination budesonide/formoterol inhaler according to a single maintenance and reliever therapy regimen or fixed dose budesonide/formoterol with salbutamol as reliever (Standard) regimen. Medication use was measured by electronic monitors. The thresholds for high, marked and extreme beta-agonist use days were defined in the single maintenance and reliever therapy arm as: >8, >12 and >16 actuations of budesonide/formoterol in excess of four maintenance doses, respectively; and in the Standard arm as: >16, >24 and >32 actuations of salbutamol, respectively. Whether a medical review was obtained within 48 h of an overuse episode was determined by review of data collected during the study by participant report. The mean (standard deviation) proportion of days in which high, marked and extreme beta-agonist overuse occurred without medical review within 48 h was 0·94(0·20), 0·94(0·15) and 0·94(0·17), and 0·92(0·19), 0·90(0·26) and 0·94(0·15) for single maintenance and reliever therapy and Standard regimens, respectively. In at least 90% of days, in which beta-agonist overuse occurred, patients did not obtain medical review within 48 h of beta-agonist overuse, regardless of the magnitude of overuse or the inhaled corticosteroid/long-acting beta-agonist regimen. RELIEVER INHALER OVERUSE AND DELAY IN MEDICAL REVIEW IN ASTHMA: In asthma, overuse of beta-agonist reliever medication and delay in seeking medical review in an exacerbation are linked to asthma deaths. Janine Pilcher at the Medical Research Institute of New Zealand, and co-workers, conducted a review of data from a study of 303 adult patients with severe asthma, followed over 24 weeks. The patients were allocated to either a budesonide/formoterol, or a salbutamol inhaler to take for symptom relief, in addition to their maintenance treatment. Inhalers were fitted with electronic monitors, to accurately document every use. In both groups, on 90% of days when an exacerbation requiring excess use of an inhaler occurred, patients did not follow-up with medical professionals within 48 h as advised. Further, in both groups, 'extreme' reliever inhaler use was recorded at least once in around one in four patients.

Cohort feasibility study of an intermittent pneumatic compression device within a below-knee cast for the prevention of venous thromboembolism.

OBJECTIVES: To determine the likely enrolment rate of eligible participants into a randomised controlled trial (RCT) in which a within-cast intermittent pneumatic compression device using Jet Impulse Technology (IPC/JIT) is 1 of 3 possible interventions in a RCT for the prevention of venous thromboembolism (VTE) in the clinical setting of isolated lower limb cast immobilisation. DESIGN: A prospective, open-label feasibility study of the IPC/JIT device placed within a lower limb cast. SETTING: Wellington Regional Hospital Fracture Clinic. PARTICIPANTS: Individuals aged 18-70 who presented with a lower limb injury requiring a minimum of 4 weeks below-knee cast immobilisation. INTERVENTION: Placement of an IPC/JIT device within lower limb cast. OUTCOME MEASURES: The main outcome measure was the proportion of eligible participants who participated in the feasibility study. Secondary outcome measures included adherence to device usage throughout the study, ease of application of the device and adverse events potentially associated with its use. RESULTS: The proportion of potentially eligible participants for the IPC/JIT device was only 7/142 (5%), 95% CI 2 to 9.9. Devices were used for a mean (range) of 4.1 (1.9 to 10.2) hours per day and none of 7 participants had adequate adherence to the device. 3 of the 7 participants suffered an adverse event, including 1 deep vein thrombosis, 2 dorsal foot ulcer and 1 skin maceration. CONCLUSIONS: A within-cast IPC/JIT device is unlikely to be a feasible randomisation arm for a RCT assessing possible interventions for the reduction of VTE risk in the clinical setting of lower limb injury requiring below knee cast immobilisation for a minimum of 4 weeks. TRIAL REGISTRATION NUMBER: ANZCTR 12615000192583.

Validation of a metered dose inhaler electronic monitoring device: implications for asthma clinical trial use.

BACKGROUND: The SmartTouch Ventolin monitor (Adherium, Auckland, New Zealand) is an electronic monitor for use with a Ventolin metered dose inhaler, which records the date and time of inhaler actuations. This technology has the potential to allow in-depth analysis of patterns of inhaler use in clinical trial settings. The aim of this study was to determine the accuracy of the SmartTouch Ventolin monitor in recording Ventolin actuations. METHODS: 20 SmartTouch Ventolin monitors were attached to Ventolin metered dose inhalers. Bench testing was performed over a 10-week period, to reflect the potential time frame between visits in a clinical trial. Inhaler actuations were recorded in a paper diary, which was compared with data uploaded from the monitors. RESULTS: 2560 actuations were performed during the 10-week study period. Monitor sensitivity for diary-recorded actuations was 99.9% with a lower 97.5% confidence bound of 99.7%. The positive predictive value for diary-recorded actuations was 100% with a 97.5% lower confidence bound of 99.9%. CONCLUSIONS: The SmartTouch Ventolin monitor is highly accurate in recording and retaining electronic data. It can be recommended for use in clinical trial settings in which training and quality control systems are incorporated into study protocols to ensure accurate data acquisition.