Second international consensus report on gaps and opportunities for the clinical translation of precision diabetes medicine

Precision medicine is part of the logical evolution of contemporary evidence-based medicine that seeks to reduce errors and optimize outcomes when making medical decisions and health recommendations. Diabetes affects hundreds of millions of people worldwide, many of whom will develop life-threatening complications and die prematurely. Precision medicine can potentially address this enormous problem by accounting for heterogeneity in the etiology, clinical presentation and pathogenesis of common forms of diabetes and risks of complications. This second international consensus report on precision diabetes medicine summarizes the findings from a systematic evidence review across the key pillars of precision medicine (prevention, diagnosis, treatment, prognosis) in four recognized forms of diabetes (monogenic, gestational, type 1, type 2). These reviews address key questions about the translation of precision medicine research into practice. Although not complete, owing to the vast literature on this topic, they revealed opportunities for the immediate or near-term clinical implementation of precision diabetes medicine; furthermore, we expose important gaps in knowledge, focusing on the need to obtain new clinically relevant evidence. Gaps include the need for common standards for clinical readiness, including consideration of cost-effectiveness, health equity, predictive accuracy, liability and accessibility. Key milestones are outlined for the broad clinical implementation of precision diabetes medicine.

Are non-invasive estimations of plasma volume an accurate measure of congestion in patients with chronic heart failure?

AIMS

We report associations between different formulae for estimating plasma volume status (PVS) and clinical and ultrasound markers of congestion in patients with chronic heart failure (CHF) enrolled in the Hull Lifelab registry.

METHODS AND RESULTS

Cohort 1 comprised patients with data on signs and symptoms at initial evaluation (n = 3505). Cohort 2 included patients with ultrasound assessment of congestion [lung B-line count, inferior vena cava (IVC) diameter, jugular vein distensibility (JVD) ratio] (N = 341). Two formulae for PVS were used: (a) Hakim (HPVS) and (b) Duarte (DPVS). Results were compared with clinical and ultrasound markers of congestion. Outcomes assessed were mortality and the composite of heart failure (HF) hospitalisation and all-cause mortality. In cohort 1, HPVS was associated with mortality [hazard ratio (HR) per unitary increase = 1.02 (1.01-1.03); P < 0.001]. In cohort 2, HPVS was associated with B-line count (HR) = 1.05 [95% confidence interval (CI) (1.01-1.08); P = 0.02] and DPVS with the composite outcome [HR = 1.26 (1.01-1.58); P = 0.04]. HPVS and DPVS were strongly related to haemoglobin concentration and HPVS to weight. After multivariable analysis, there were no strong or consistent associations between PVS and measures of congestion, severity of symptoms, or outcome. By contrast, log[NTproBNP] was strongly associated with all three.

CONCLUSION

Amongst patients with CHF, HPVS and DPVS are not strongly or consistently associated with clinical or ultrasound evidence of congestion, nor clinical outcomes after multivariable adjustment. They appear only to be surrogates of the variables from which they are calculated with no intrinsic clinical utility.

The relation between change in left ventricular systolic function and subsequent mortality in patients with chronic heart failure

Background

Increasing severity of impairment of left ventricular systolic dysfunction (LVSD) in patients with chronic heart failure (CHF) is associated with higher mortality. However, the relation between temporal changes in LVSD severity and long-term clinical outcome is unknown.

Purpose

We therefore investigated the effects of change of LVSD as measured by serial echocardiography on all-cause mortality in patients with CHF.

Methods

Patients with CHF defined as the presence of compatible symptoms and either at least moderate LVSD or NTproBNP &gt;125 ng/L were enrolled. LVSD was qualitatively assessed as: none, mild, moderate, and severe. Echocardiography was performed at baseline and 12 months. The primary endpoint was all-cause mortality. Cox proportional hazard models were used to assess the relation between changes in LVSD and outcome. Hazard ratios (HR) are reported with 95% confidence intervals (CI).

Results

At baseline, 170 (11%) had no, 231 (16%) mild, 633 (43%) moderate and 453 (30%) severe LVSD. Amongst patients with either moderate or severe LVSD at baseline, 40% had improvement in function at 12 months (figure 1). Amongst patients with no LVSD at baseline, only 14% had deterioration of function. During subsequent median follow up of 2773 days, 868 patients died. Worsening of LVSD was associated with increasing all-cause mortality in patients with moderate LVSD and severe LVSD at baseline, but this was not significant after adjustment for covariables (table 1). Improvement of LVSD was independently associated with better survival in patients with moderate LVSD at baseline (HR 0.72 (95% CI: 0.53–0.98, p=0.04).

Conclusion

Greater severity of LVSD at baseline is associated with increasing likelihood of improvement. Amongst patients with moderate LVSD, improvement in LVSD is independently associated with survival.

Funding Acknowledgement

Type of funding sources: Public Institution(s).

Inferior vena cava diameter adds information to pulmonary artery systolic pressure in outpatients with heart failure

Background

Evaluation of pulmonary arterial pressure (PAP) is recommended by guidelines to diagnose and monitor congestion in patients with heart failure (HF). However, the high compliance of the venous system might buffer the effects of a large increase in intravascular volume and delay an elevation in PAP. Therefore, measuring inferior vena cava (IVC) diameter by ultrasounds might add important information in patients with HF, regardless of PAP.

Aim

To evaluate the relationship between the IVC diameter and systolic PAP (PAsP) assessed by echocardiography with mortality in outpatients with HF.

Methods

We enrolled consenting out-patients attending a community HF clinic for initial diagnosis or follow-up in Kingston upon Hull, UK between 2009–2012. HF was defined as the presence of relevant symptoms and signs and objective evidence of cardiac dysfunction: either a left ventricular systolic function (LVEF) &lt;50% or elevated amino-terminal pro-brain natriuretic peptide (NT-proBNP) ≥125 pg/ml. IVC was considered dilated when &gt;2.0 cm, PAsP elevated when &gt;35 mmHg.

Results

Amongst the 874 patients enrolled, median age was 75 years, 68% were men, median LVEF was 44% and median NT-proBNP was 1125 pg/ml. 468 patients (54%) had normal IVC and PAsP, 117 (13%) had normal IVC but elevated PAsP, 75 (8%) had dilated IVC but normal PAsP and 214 (25%) had both dilated IVC and elevated PAsP. Compared to those with normal IVC and PAsP, those with elevated PAsP but normal IVC were older, more likely to be women, and had higher LVEF and NT-proBNP, whilst those with dilated IVC but normal PAsP had similar age and LVEF, but more signs of congestion and higher NT-proBNP. Compared to those with both normal IVC and PAsP (reference), those with dilated IVC but normal PAsP (HR: 1.83; CI: 1.04–3.25; P=0.037) or elevated PAsP but normal IVC (HR: 1.88; CI: 1.25–2.85; P=0.003) had a similarly increased risk of death but those with a dilated IVC and elevated PAsP had the greatest risk (HR: 4.16; CI: 3.10–5.57; P&lt;0.001).

Conclusion

A dilated IVC is associated with mortality even when PAsP is not elevated. Tailoring treatments to reduce IVC diameter is a strategy worth exploring to improve outcomes in outpatients with heart failure.

Funding Acknowledgement

Type of funding sources: None.

Genetic Reduction of Glucose Metabolism Preserves Functional β-Cell Mass in KATP-Induced Neonatal Diabetes

β-Cell failure and loss of β-cell mass are key events in diabetes progression. Although insulin hypersecretion in early stages has been implicated in β-cell exhaustion/failure, loss of β-cell mass still occurs in KATP gain-of-function (GOF) mouse models of human neonatal diabetes in the absence of insulin secretion. Thus, we hypothesize that hyperglycemia-induced increased β-cell metabolism is responsible for β-cell failure and that reducing glucose metabolism will prevent loss of β-cell mass. To test this, KATP-GOF mice were crossed with mice carrying β-cell-specific glucokinase haploinsufficiency (GCK+/-), to genetically reduce glucose metabolism. As expected, both KATP-GOF and KATP-GOF/GCK+/- mice showed lack of glucose-stimulated insulin secretion. However, KATP-GOF/GCK+/- mice demonstrated markedly reduced blood glucose, delayed diabetes progression, and improved glucose tolerance compared with KATP-GOF mice. In addition, decreased plasma insulin and content, increased proinsulin, and augmented plasma glucagon observed in KATP-GOF mice were normalized to control levels in KATP-GOF/GCK+/- mice. Strikingly, KATP-GOF/GCK+/- mice demonstrated preserved β-cell mass and identity compared with the marked decrease in β-cell identity and increased dedifferentiation observed in KATP-GOF mice. Moreover KATP-GOF/GCK+/- mice demonstrated restoration of body weight and liver and brown/white adipose tissue mass and function and normalization of physical activity and metabolic efficiency compared with KATP-GOF mice. These results demonstrate that decreasing β-cell glucose signaling can prevent glucotoxicity-induced loss of insulin content and β-cell failure independently of compensatory insulin hypersecretion and β-cell exhaustion.

Hypochloraemia following admission to hospital with heart failure is common and associated with an increased risk of readmission or death: a report from OPERA-HF

AIMS

Hypochloraemia is common in patients hospitalized with heart failure (HF) and associated with a high risk of adverse outcomes during admission and following discharge. We assessed the significance of changes in serum chloride concentrations in relation to serum sodium and bicarbonate concentrations during admission in a cohort of 1002 consecutive patients admitted with HF and enrolled into an observational study based at a single tertiary centre in the UK.

METHODS AND RESULTS

Hypochloraemia (<96 mmol/L), hyponatraemia (<135 mmol/L), and metabolic alkalosis (bicarbonate >32 mmol/L) were defined by local laboratory reference ranges. Outcomes assessed were all-cause mortality, all-cause mortality or all-cause readmission, and all-cause mortality or HF readmission. Cox regression and Kaplan-Meier curves were used to investigate associations with outcome. During a median follow-up of 856 days (interquartile range 272-1416), discharge hypochloraemia, regardless of serum sodium, or bicarbonate levels was associated with greater all-cause mortality [hazard ratio (HR) 1.44, 95% confidence interval (CI) 1.15-1.79; P = 0.001], all-cause mortality or all-cause readmission (HR 1.26, 95% CI 1.04-1.53; P = 0.02), and all-cause mortality or HF readmission (HR 1.41, 95% CI 1.14-1.74; P = 0.002) after multivariable adjustment. Patients with concurrent hypochloraemia and natraemia had lower haemoglobin and haematocrit, suggesting congestion; those with hypochloraemia and normal sodium levels had more metabolic alkalosis, suggesting decongestion.

CONCLUSION

Hypochloraemia is common at discharge after a hospitalization for HF and is associated with worse outcome subsequently. It is an easily measured clinical variables that is associated with morbidity or mortality of any cause.

High-fat diet prevents the development of autoimmune diabetes in NOD mice

AIMS

Type 1 diabetes (T1D) has a strong genetic predisposition and requires an environmental trigger to initiate the beta-cell autoimmune destruction. The rate of childhood obesity has risen in parallel to the proportion of T1D, suggesting high-fat diet (HFD)/obesity as potential environmental triggers for autoimmune diabetes. To explore this, non-obese diabetic (NOD) mice were subjected to HFD and monitored for the development of diabetes, insulitis and beta-cell stress.

MATERIALS AND METHODS

Four-week-old female NOD mice were placed on HFD (HFD-NOD) or standard chow-diet. Blood glucose was monitored weekly up to 40 weeks of age, and glucose- and insulin-tolerance tests performed at 4, 10 and 15 weeks. Pancreata and islets were analysed for insulin secretion, beta-cell mass, inflammation, insulitis and endoplasmic reticulum stress markers. Immune cell levels were measured in islets and spleens. Stool microbiome was analysed at age 4, 8 and 25 weeks.

RESULTS

At early ages, HFD-NOD mice showed a significant increase in body weight, glucose intolerance and insulin resistance; but paradoxically, they were protected from developing diabetes. This was accompanied by increased insulin secretion and beta-cell mass, decreased insulitis, increased splenic T-regulatory cells and altered stool microbiome.

CONCLUSIONS

This study shows that HFD protects NOD mice from autoimmune diabetes and preserves beta-cell mass and function through alterations in gut microbiome, increased T-regulatory cells and decreased insulitis. Further studies into the exact mechanism of HFD-mediated prevention of diabetes in NOD mice could potentially lead to interventions to prevent or delay T1D development in humans.

The efficacy of using a holistic 4-domain approach in evaluating frailty in ambulatory patient with heart failure

Background

Recently, the Heart Failure Association (HFA) of the European Society of Cardiology (ESC) proposed a four-domain approach to assess frailty in patients with heart failure (HF), to tailor treatment and potentially improve outcomes. The efficacy of such approach in detecting frailty and predicting outcome in patients with HF is unknown.

Aim

To study the prevalence and prognostic value of four different types of frailty deficits: clinical, physical, cognitive and social frailty in ambulatory patients with HF.

Methods

We assessed prospectively consecutive patients attending a routine follow-up visit. Patients with ≥5 non-HF comorbidities were classified as having a clinical deficit. Those who scored ≥3 using the Fried criteria were classified as having a physical deficit. Those who failed to complete a clock test accurately were classified as having a cognitive deficit. Those who lived alone or in a residential home were classified as having a social deficit. All patients were followed for a minimum of 1 year. The primary end point is all-cause mortality.

Results

We enrolled 467 patients (67% male, median (25th–75th centile) age 76 (69–82) years, median (25th–75th centile) NT-proBNP 1156 (469–2463) ng/L). 65% of patients had clinical deficits, 52% had a physical deficit, 39% had a social deficit and 18% had a cognitive deficit. 28% had 2, 19% had 3, 8% of patients had all 4 deficits; 16% had none. An increasing number of frailty deficits was associated with worse symptoms, higher NT-proBNP and less likelihood of being prescribed guideline-indicated HF treatment.

During a median follow-up of 554 days, 82 patients died. The presence of any frailty deficit was associated with increased risk of mortality. (Figure 1) The more frailty deficit a patient had, the higher the risk of mortality (Figure 2). A base model (including age, body mass index, NYHA class and log [NT-proBNP]) for predicting mortality at 1 year achieved a C-statistic of 0.78. Addition of all four deficits improved the performance of the base model (C-statistic = 0.82).

Conclusion

Clinical, physical, cognitive and social deficits are common in patients with HF and are associated with a poor outcome. Future studies should evaluate how a domain-based approach can be used to optimise care for frail patients with HF.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

SARS-CoV-2 infection of islet β cells: Evidence and implications

The health of insulin-producing β cells is critical for normoglycemia. Wu et al.¹ and Tang et al.² provide evidence in vitro that β cells can be infected by SARS-CoV-2 virus, possibly contributing to worsening hyperglycemia seen during the COVID-19 pandemic.

Osteoanabolic therapy for osteoporosis in women

Therapy to activate bone formation is required to reverse and restore the damaged bone architecture found in women with postmenopausal osteoporosis. The osteoanabolic drugs include teriparatide, which has been available for several years, and abaloparatide and romosozumab, novel osteoanabolic drugs that have become available more recently. By stimulating bone formation, these drugs produce greater increases in bone mass and bone strength, and they do so more quickly compared to the commonly used anti-remodeling (also called antiresorptive) drugs such as bisphosphonates. In head-to-head trials, teriparatide and romosozumab reduce fracture risk more effectively than do oral bisphosphonates in women with osteoporosis and high fracture risk. Osteoanabolic drugs have little role in the prevention of bone loss during early menopause, but they have an important place in the treatment of women at very high risk of fracture or who remain at high fracture risk after a course of bisphosphonate therapy. Primarily because of the high cost of the drugs, these therapies are initiated by specialists rather than primary-care physicians in most countries. This review will present the evidence for efficacy and safety of these drugs so that clinicians may discern their appropriate use when caring for postmenopausal women with osteoporosis.

Adult Beliefs About the Migration Motives of Unaccompanied Honduran Youth

A number of researchers have examined undocumented migration from Central America. This literature lacks information about adult beliefs regarding the motivations of minors who journey from Central America unaccompanied and undocumented. Using data from a recent survey conducted in Honduras, we examine adult Hondurans’ beliefs about why unaccompanied minors leave the country unaccompanied. The dependent variable is a dummy variable that measures “why children leave the country.” Predictor variables are attitudes toward smuggling, willingness to leave without documentation, deportation experience, age, income, and residence in the northern part of Honduras. Using multinomial logistic regression, we find support for four of the eight hypotheses. Findings indicate that adults from the northern region are most likely to believe minors would leave for reasons associated with undocumented immigration. Those who are younger, with lower incomes, and with less access to sanitation are more likely to believe minors would leave without documentation.

P4514Agreement and prognostic significance of 6 frailty tools in patients with chronic heart failure

Background

Frailty is common in patients with chronic heart failure (CHF) and is associated with adverse outcome. Many frailty tools are available, however, there is no standard way of evaluating frailty in patients with CHF.

Purpose

To report the prevalence of frailty, agreement and prognostic significance amongst 3 frailty assessment tools and 3 screening tools in CHF patients.

Methods

We comprehensively studied frailty using 6 frailty tools. Frailty screening tools include: Clinical frailty scale (CFS); Derby frailty index & Acute frailty network frailty criteria. Frailty assessment tools include: Fried criteria; Edmonton frailty score & Deficit index. Since there is no gold standard in evaluating frailty in CHF patients, for each of the frailty tools, we used the results of the other 5 tools to produce a combined frailty index which we used as a “standard” frailty tool. Subjects were defined as frail if so identified by at least 3 out of 5 tools.

Results

467 consecutive ambulatory CHF patients (67% male, median age 76 (IQR: 69–82) years, median NTproBNP 1156 (IQR: 469–2463) ng/L) and 87 controls (79% male, median age 73 (IQR: 69–77 years) were studied.

Prevalence of frailty was much higher in CHF patients than in controls (30–52% vs 2–15%, respectively). Amongst the frailty screening tools, DFI scored the greatest proportion of patients as frail (48%) while CFS scored the lowest proportion as frail (44%). Amongst the assessment tools, Fried criteria scored the greatest proportion of patients as frail (52%) while EFS scored the lowest proportion as frail (30%). Frail patients were older, have worse symptoms, higher NTproBNP and more co-morbidities compared to non-frail patients.

Of the screening tools, CFS had the strongest agreement with assessment tools (kappa coefficient: 0.65–0.72, all p<0.001). CFS had the highest sensitivity (87%) and specificity (89%) amongst screening tools and the lowest misclassification rate (12%) amongst all 6 frailty tools in identifying frailty according to the combined frailty index.

During a median follow-up of 559 days (IQR 512–629 days), 82 (18%) patients died. 55% (N=45) of frail patients died of non-cardiovascular causes. Worsening frailty as detected by all 6 frailty tools was associated with worse outcome. A base model for mortality prediction including sex, NYHA class (III/IV vs I/II), BMI, log NTproBNP and haemoglobin had a C-statistics of 0.78. Amongst frailty tools: CFS and Fried criteria increased model performance most compared with base model (c-statistics: 0.80 for both). Patients who were frail according to CFS had a 9 times greater mortality risk than non-frail patients (Figure).

Conclusion

Frailty is common in CHF patients and is associated with worse outcome. CFS is a simple screening tool which identifies a similar group as lengthy assessment tools and has similar prognostic significance. Frailty screening should be incorporated into routine care of patients with CHF.

Acknowledgement/Funding

None

P2506Prognostic importance of ventilatory efficiency in healthy subjects

Background

Low cardiorespiratory fitness, defined by reduced maximal oxygen consumption (VO2), is a predictor of mortality in patients without chronic disease. However, the relation between ventilatory efficiency (as measured by the slope of the relation between ventilation (VE) and carbon dioxide production (VCO2)) and all-cause mortality is unknown.

Purpose

To assess the relation between variables derived from cardiopulmonary exercise testing and long-term survival in normal subjects

Method

We recruited 145 healthy subjects, with no history of chronic disease (57% male, mean age 63±12) from primary care at random. All participants underwent cardiopulmonary exercise testing at baseline. Participants were followed for 15.5±3.5 years. The primary end-point was all-cause mortality. Cox-proportional hazard models were used to assess the relationship between measures of exercise performance and outcome. Hazard ratios (HR) are reported with 95% confidence intervals (CI).

Results

During follow up, 34 participants (23.4%) died. On univariable analysis, VE/VCO2 slope, peak VO2, respiratory exchange ratio at peak exercise, peak heart rate and 6-minute walk test distance were significant predictors of all-cause mortality (table 1). However, only VE/VCO2 slope (HR per unit increase: 1.13, 95% CI: 1.00–1.28, P=0.043) and peak heart rate (HR per 10 unit increase: 0.73, 95% CI: 0.57–0.93, P=0.010) were independent predictors of all-cause mortality on multivariable analysis.

Table 1. Cox regression analysis (univariable and multivariable) for cardiopulmonary exercise testing measures and all-cause mortality HR Presentation Univariable analysis Multivariable analysis HR 95% CI p value HR 95% CI p value Peak VO2 (ml/kg/min) Per unit increase 0.90 0.86–0.95 &lt;0.001 0.94 0.86–1.03 0.214 VE/VCO2 slope Per unit increase 1.08 1.01–1.17 0.049 1.13 1.00–1.28 0.043 Exercise RER Per 0.1 unit increase 0.46 0.31–0.67 &lt;0.001 0.72 0.45–1.17 0.185 Peak heart rate (bpm) Per 10 unit increase 0.73 0.65–0.81 &lt;0.001 0.73 0.57–0.93 0.010 6MWT (metre) Per 25 unit increase 0.92 0.86–0.98 0.009 1.02 0.86–1.17 0.789 Peak systolic BP (mmHg) Per 10 unit increase 1.13 0.98–1.31 0.101 – – – Multivariable analysis is adjusted for age, body mass index, sex, smoking, resting systolic blood pressure and forced vital capacity. Abbreviations: 6MWT, 6-minute walk test; CI, confidence interval; HR, hazard ratio; RER, respiratory exchange ratio.

Conclusions

Raised VE/VCO2 slope is an independent predictor of all-cause mortality in healthy patients with no history of chronic disease.

Mode of presentation and mortality amongst patients hospitalized with heart failure? A report from the First Euro Heart Failure Survey

BACKGROUND

Heart failure is heterogeneous in aetiology, pathophysiology, and presentation. Despite this diversity, clinical trials of patients hospitalized for HF deal with this problem as a single entity, which may be one reason for repeated failures.

METHODS

The first EuroHeart Failure Survey screened consecutive deaths and discharges of patients with suspected heart failure during 2000-2001. Patients were sorted into seven mutually exclusive hierarchical presentations: (1) with cardiac arrest/ventricular arrhythmia; (2) with acute coronary syndrome; (3) with rapid atrial fibrillation; (4) with acute breathlessness; (5) with other symptoms/signs such as peripheral oedema; (6) with stable symptoms; and (7) others in whom the contribution of HF to admission was not clear.

RESULTS

The 10,701 patients enrolled were classified into the above seven presentations as follows: 260 (2%), 560 (5%), 799 (8%), 2479 (24%), 1040 (10%), 703 (7%), and 4691 (45%) for which index-admission mortality was 26%, 20%, 10%, 8%, 6%, 6%, and 4%, respectively. Compared to those in group 7, the hazard ratios for death during the index admission were 4.9 (p ≤ 0.001), 4.0 (p < 0.001), 2.2 (p < 0.001), 2.1 (p < 0.001), 1.4 (p < 0.04) and 1.4 (p = 0.04), respectively. These differences were no longer statistically significant by 12 weeks.

CONCLUSION

There is great diversity in the presentation of heart failure that is associated with very different short-term outcomes. Only a minority of hospitalizations associated with suspected heart failure are associated with acute breathlessness. This should be taken into account in the design of future clinical trials.

Telemonitoring in subjects with newly diagnosed heart failure with reduced ejection fraction: From clinical research to everyday practice

INTRODUCTION

Heart failure is increasingly common, and characterised by frequent admissions to hospital. To try and reduce the risk of hospitalisation, techniques such as telemonitoring (TM) may have a role. We wanted to determine if TM in patients with newly diagnosed heart failure and ejection fraction <40% reduces the risk of readmission or death from any cause in a 'real-world' setting.

METHODS

This is a retrospective study of 124 patients (78.2% male; 68.6 ± 12.6 years) who underwent TM and 345 patients (68.5% male; 70.2 ± 10.7 years) who underwent the usual care (UC). The TM group were assessed daily by body weight, blood pressure and heart rate using electronic devices with automatic transfer of data to an online database. Follow-up was 12 months.

RESULTS

Death from any cause occurred in 8.1% of the TM group and 19% of the UC group ( p = 0.002). There was no difference between the two groups in all-cause hospitalisation, either in the number of subjects hospitalised ( p = 0.7) or in the number of admissions per patient ( p = 0.6). There was no difference in the number of heart-failure-related readmissions per person between the two groups ( p = 0.5), but the number of days in hospital per person was higher in the UC group ( p = 0.03). Also, there were a significantly greater number of days alive and out of hospital for the patients in the TM group compared with the UC group ( p = 0.0001).

DISCUSSION

TM is associated with lower any-cause mortality and also has the potential to reduce the number of days lost to hospitalisation and death.

Effects of human recombinant growth hormone on exercise capacity, cardiac structure, and cardiac function in patients with adult-onset growth hormone deficiency

Objective

Epidemiological studies suggest that adult-onset growth hormone deficiency (AGHD) might increase the risk of death from cardiovascular causes.

Methods

This was a 6-month double-blind, placebo-controlled, randomised, cross-over trial followed by a 6-month open-label phase. Seventeen patients with AGHD received either recombinant human growth hormone (rGH) (0.4 mg injection daily) or placebo for 12 weeks, underwent washout for 2 weeks, and were then crossed over to the alternative treatment for a further 12 weeks. Cardiac magnetic resonance imaging, echocardiography, and cardiopulmonary exercise testing were performed at baseline, 12 weeks, 26 weeks, and the end of the open phase (12 months). The results were compared with those of 16 age- and sex-matched control subjects.

Results

At baseline, patients with AGHD had a significantly higher systolic blood pressure, ejection fraction, and left ventricular mass than the control group, even when corrected for body surface area. Treatment with rGH normalised the insulin-like growth factor 1 concentration without an effect on exercise capacity, cardiac structure, or cardiac function.

Conclusion

Administration of rGH therapy for 6 to 9 months failed to normalise the functional and structural cardiac differences observed in patients with AGHD when compared with a control group.

Estimated peak functional capacity: an accurate method for assessing change in peak oxygen consumption after cardiac rehabilitation?

OBJECTIVE

Cardiopulmonary exercise testing (CPET) is the 'gold standard' method of determining VO_2peak . When CPET is unavailable, VO_2peak may be estimated from treadmill or cycle ergometer workloads and expressed as estimated metabolic equivalents (METs). Cardiac rehabilitation (CR) programmes use estimated VO_2peak (METs) to report changes in cardiorespiratory fitness (CRF). However, the accuracy of determining changes in VO_2peak based on estimated functional capacity is not known.

METHODS

A total of 27 patients with coronary heart disease (88·9% male; age 59·5 ± 10·0 years, body mass index 29·6 ± 3·8 kg m^-2 ) performed maximal CPET before and after an exercise-based CR intervention. VO_2peak was directly determined using ventilatory gas exchange data and was also estimated using the American College of Sports Medicine (ACSM) leg cycling equation. Agreement between changes in directly determined VO_2peak and estimated VO_2peak was evaluated using Bland-Altman limits of agreement (LoA) and intraclass correlation coefficients.

RESULTS

Directly determined VO_2peak did not increase following CR (0·5 ml kg^-1 min^-1 (2·7%); P = 0·332). Estimated VO_2peak increased significantly (0·4 METs; 1·4 ml kg^-1  min^-1 ; 6·7%; P = 0·006). The mean bias for estimated VO_2peak versus directly determined VO_2peak was 0·7 ml kg^-1  min^-1 (LoA -4·7 to 5·9 ml  kg^-1  min^-1 ). Aerobic efficiency (ΔVO₂ /ΔWR slope) was significantly associated with estimated VO_2peak measurement error.

CONCLUSION

Change in estimated VO_2peak derived from the ACSM leg cycling equation is not an accurate surrogate for directly determined changes in VO_2peak . Our findings show poor agreement between estimates of VO_2peak and directly determined VO_2peak . Applying estimates of VO_2peak to determine CRF change may over-estimate the efficacy of CR and lead to a different interpretation of study findings.

Hypercalcemia in Patients with Williams-Beuren Syndrome

OBJECTIVE

To evaluate the timing, trajectory, and implications of hypercalcemia in Williams-Beuren syndrome (WBS) through a multicenter retrospective study.

STUDY DESIGN

Data on plasma calcium levels from 232 subjects with WBS aged 0-67.1 years were compared with that in controls and also with available normative data. Association testing was used to identify relevant comorbidities.

RESULTS

On average, individuals with WBS had higher plasma calcium levels than controls, but 86.7% of values were normal. Nonpediatric laboratories overreport hypercalcemia in small children. When pediatric reference intervals were applied, the occurrence of hypercalcemia dropped by 51% in infants and by 38% in toddlers. Across all ages, 6.1% of the subjects had actionable hypercalcemia. In children, actionable hypercalcemia was seen in those aged 5-25 months. In older individuals, actionable hypercalcemia was often secondary to another disease process. Evidence of dehydration, hypercalciuria, and nephrocalcinosis were common in both groups. Future hypercalcemia could not be reliably predicted by screening calcium levels. A subgroup analysis of 91 subjects found no associations between hypercalcemia and cardiovascular disease, gastrointestinal complaints, or renal anomalies. Analyses of electrogradiography data showed an inverse correlation of calcium concentration with corrected QT interval, but no acute life-threatening events were reported.

CONCLUSIONS

Actionable hypercalcemia in patients with WBS occurs infrequently. Although irritability and lethargy were commonly reported, no mortality or acute life-threatening events were associated with hypercalcemia and the only statistically associated morbidities were dehydration, hypercalciuria, and nephrocalcinosis.

Endoplasmic reticulum stress in beta cells and autoimmune diabetes

Type 1 diabetes results from the autoimmune destruction of pancreatic β cells, leading to insulin deficiency and hyperglycemia. Although multiple attempts have been made to slow the autoimmune process using immunosuppressive or immunomodulatory agents, there are still no effective treatments that can delay or reverse the progression of type 1 diabetes in humans. Recent studies support endoplasmic reticulum (ER) as a novel target for preventing the initiation of the autoimmune reaction, propagation of inflammation, and β cell death in type 1 diabetes. This review highlights recent findings on ER stress in β cells and development of type 1 diabetes and introduces potential new treatments targeting the ER to combat this disorder.

Integrin α1β1 protects against signs of post-traumatic osteoarthritis in the female murine knee partially via regulation of epidermal growth factor receptor signalling

OBJECTIVE

To investigate the role of integrin α1β1 in the progression of post-traumatic osteoarthritis (PTOA), and elucidate the contribution of epidermal growth factor receptor (EGFR) signalling to the mechanism by which integrin α1β1 might control PTOA. We hypothesised that integrin α1β1 plays a protective role in the course of PTOA and that the effect of PTOA (e.g., synovitis, loss of cartilage and growth of osteophytes) would be exacerbated in mice lacking integrin α1β1 at every time point post destabilisation of medial meniscus (DMM).

METHODS

DMM or sham surgery was performed on integrin α1-null and wild type (WT) mice and the progression of PTOA analysed at 2, 4, 8 and 12 weeks post-surgery (PS) using micro-computed tomography (microCT), histology, and immunohistochemistry. In addition, the effects of EGFR blockade were examined by treating the mice with the EGFR inhibitor erlotinib.

RESULTS

Integrin α1-null female, but not male, mice showed earlier cartilage degradation post DMM surgery compared to WT controls. Furthermore, erlotinib treatment resulted in significantly less cartilage damage in integrin α1-null but not WT mice. Independent of genotype, erlotinib treatment significantly mitigated the effects of PTOA on many tissues of female mice including meniscal and fabella bone volume, subchondral bone thickness and density and cartilage degradation. In contrast, reduced EGFR signalling had little effect on signs of PTOA in male mice.

CONCLUSION

Integrin α1β1 protects against PTOA-induced cartilage degradation in female mice partially via the reduction of EGFR signalling. Furthermore, reduction of EGFR signalling protects against the development of PTOA in female, but not male mice.

Does pulmonary rehabilitation reduce peripheral blood pressure in patients with chronic obstructive pulmonary disease?

Pulmonary rehabilitation (PR) can improve aerobic exercise capacity, health-related quality of life and dyspnoea in patients with chronic obstructive pulmonary disease (COPD). Recent studies have suggested that exercise training may improve blood pressure and arterial stiffness, albeit in small highly selected cohorts. The aim of the study was to establish whether supervised outpatient or unsupervised home PR can reduce peripheral blood pressure. Resting blood pressure was measured in 418 patients with COPD before and after outpatient PR, supervised by a hospital-based team (HOSP). Seventy-four patients with COPD undergoing an unsupervised home-based programme acted as a comparator group (HOME). Despite significant improvements in mean (95% confidence interval) exercise capacity in the HOSP group (56 (50-60) m, p < 0.001) and HOME group (30 (17-42) m, p < 0.001) systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial blood pressure (MAP) did not change in either the HOSP (SBP: p = 0.47; DBP: p = 0.06; MAP: p = 0.38) or HOME group (SBP: p = 0.67; DBP: p = 0.38; MAP: p = 0.76). Planned subgroup analysis of HOSP patients with known hypertension and/or cardiovascular disease showed no impact of PR upon blood pressure. PR is unlikely to reduce blood pressure, and by implication, makes a mechanism of action in which arterial stiffness is reduced, less likely.

Sarcopenia in COPD: prevalence, clinical correlates and response to pulmonary rehabilitation

BACKGROUND

Age-related loss of muscle, sarcopenia, is recognised as a clinical syndrome with multiple contributing factors. International European Working Group on Sarcopenia in Older People (EWGSOP) criteria require generalised loss of muscle mass and reduced function to diagnose sarcopenia. Both are common in COPD but are usually studied in isolation and in the lower limbs.

OBJECTIVES

To determine the prevalence of sarcopenia in COPD, its impact on function and health status, its relationship with quadriceps strength and its response to pulmonary rehabilitation (PR).

METHODS

EWGSOP criteria were applied to 622 outpatients with stable COPD. Body composition, exercise capacity, functional performance, physical activity and health status were assessed. Using a case-control design, response to PR was determined in 43 patients with sarcopenia and a propensity score-matched non-sarcopenic group.

RESULTS

Prevalence of sarcopenia was 14.5% (95% CI 11.8% to 17.4%), which increased with age and Global Initiative for Chronic Obstructive Pulmonary Disease (GOLD) stage, but did not differ by gender or the presence of quadriceps weakness (14.9 vs 13.8%, p=0.40). Patients with sarcopenia had reduced exercise capacity, functional performance, physical activity and health status compared with patients without sarcopenia (p<0.001), but responded similarly following PR; 12/43 patients were no longer classified as sarcopenic following PR.

CONCLUSIONS

Sarcopenia affects 15% of patients with stable COPD and impairs function and health status. Sarcopenia does not impact on response to PR, which can lead to a reversal of the syndrome in select patients.

Clinical COPD Questionnaire in patients with chronic respiratory disease

BACKGROUND AND OBJECTIVE

The Clinical Chronic Obstructive Pulmonary Disease (COPD) Questionnaire (CCQ) is an easy to complete, health-related quality of life questionnaire which has been well-validated in COPD. The responsiveness of the CCQ in chronic respiratory disease patients other than COPD has not been previously described. The study aims were to determine if the CCQ in chronic respiratory disease correlates with other health related quality of life questionnaires, to assess the responsiveness of the CCQ to pulmonary rehabilitation and to determine the minimum important difference.

METHODS

The CCQ, COPD Assessment Test (CAT), the Chronic Respiratory Questionnaire (CRQ) and St George's Respiratory Questionnaire (SGRQ) were measured in 138 chronic respiratory disease patients completing pulmonary rehabilitation. Change in CCQ with pulmonary rehabilitation was correlated with change in the other questionnaires. The minimum important difference of the CCQ was calculated using distribution and anchor-based approaches.

RESULTS

The CCQ, CAT, CRQ and SGRQ improved significantly with rehabilitation with effect sizes of -0.43, -0.26, 0.62, -0.37. Change in CCQ correlated significantly with CAT, CRQ and SGRQ (r = 0.53, -0.64, 0.30, all P < 0.0001). The minimum important difference was -0.42 at the population level and -0.4 at the individual level.

CONCLUSIONS

The CCQ is responsive to pulmonary rehabilitation in chronic respiratory disease patients, with an MID estimated at -0.4 at the individual level.

Phenotypic characteristics associated with reduced short physical performance battery score in COPD

BACKGROUND

The Short Physical Performance Battery (SPPB) is commonly used in gerontology, but its determinants have not been previously evaluated in COPD. In particular, it is unknown whether pulmonary aspects of COPD would limit the value of SPPB as an assessment tool of lower limb function.

METHODS

In 109 patients with COPD, we measured SPPB score, spirometry, 6-min walk distance, quadriceps strength, rectus femoris cross-sectional area, fat-free mass, physical activity, health status, and Medical Research Council dyspnea score. In a subset of 31 patients with COPD, a vastus lateralis biopsy was performed, and the biopsy specimen was examined to evaluate the structural muscle characteristics associated with SPPB score. The phenotypic characteristics of patients stratified according to SPPB were determined.

RESULTS

Quadriceps strength and 6-min walk distance were the only independent predictors of SPPB score in a multivariate regression model. Furthermore, while age, dyspnea, and health status were also univariate predictors of SPPB score, FEV 1 was not. Stratification by reduced SPPB score identified patients with locomotor muscle atrophy and increasing impairment in strength, exercise capacity, and daily physical activity. Patients with mild or major impairment defined as an SPPB score < 10 had a higher proportion of type 2 fibers (71% [14] vs 58% [15], P = .04).

CONCLUSIONS

The SPPB is a valid and simple assessment tool that may detect a phenotype with functional impairment, loss of muscle mass, and structural muscle abnormality in stable patients with COPD.

Response of the COPD Assessment Test to pulmonary rehabilitation in unselected chronic respiratory disease

BACKGROUND AND OBJECTIVE

The COPD Assessment Test (CAT) is a recently introduced, simple-to-use health status instrument that takes less time to complete than better-established health status instruments. In chronic obstructive pulmonary disease (COPD) patients, the CAT improves with pulmonary rehabilitation (PR), and changes correlate with improvements in longer-established health status instruments such as the Chronic Respiratory Questionnaire (CRQ). Increasing numbers of non-COPD patients are referred for PR, but it is not known whether the CAT is responsive to PR in these populations.

METHODS

The CAT score was prospectively measured in 365 consecutive patients (255 COPD, 110 non-COPD) before and after an 8-week PR programme. Pre to post change in CAT was calculated for COPD and non-COPD patients, and correlated with change in the CRQ.

RESULTS

For both non-COPD and COPD patients, there was a similar and significant improvement in the mean (95% confidence interval) CAT score following PR (non-COPD: -2.1 (-1.0, -3.2) vs COPD: -3.0 (-2.2, -3.8); P = 0.19). Change in CAT was significantly correlated with all domains of the CRQ in non-COPD patients (all P < 0.01).

CONCLUSIONS

As in COPD patients, the CAT is immediately responsive to PR in non-COPD patients. Even in unselected chronic respiratory disease patients undergoing PR, the CAT is a practical alternative to longer-established health status questionnaires.

The impact of age and chronic kidney disease on secondary prevention post-primary percutaneous coronary intervention

OBJECTIVE

Historical data suggest elderly patients and those with chronic kidney disease (CKD) receive suboptimal secondary prevention following myocardial infarction (MI). We evaluated the impact of age and CKD on secondary prevention following primary percutaneous coronary intervention (PPCI) in a contemporary unselected cohort.

DESIGN

We studied 1169 consecutive patients from five UK centres receiving PPCI for ST elevation MI, with use of evidence-based secondary prevention at discharge assessed by age (<60, 60-75 and >75 years) and estimated glomerular filtration rate (eGFR). Follow-up prescribing practice was assessed in 567 patients.

RESULTS

One-fifth of patients receiving PPCI were >75 years. This group received fewer secondary prevention drugs at discharge compared to younger patients (P < 0.01 for β-blockers, angiotensin-converting enzyme (ACE) inhibitors/angiotensin receptor blockers (ARB) and statins). By 6 weeks post-PPCI, there was a small drop-off in evidence-based therapy; β-blocker and statin use in those >75 years fell from 90% to 86% and 96% to 93%, respectively. CKD (eGFR<60 ml/min/1.73 m(2)) was seen in 17.6%. Declining renal function was associated with age, female sex and lower use of ACE inhibitor/ARB. At discharge 83.5% of patients with eGFR<60 ml/min/1.73 m(2) were receiving ACE inhibitors/ARB, dropping to 77.5% at 6 weeks (compared with 95% and 92%, respectively, in patients with eGFR >60 ml/min/1.73 m(2)).

CONCLUSION

The uptake of secondary prevention medication is high following PPCI in the UK, even in the elderly and in those with renal dysfunction. A focus on strategies to improve up-titration and continuation of drugs following discharge is required.

Minimum clinically important difference for the COPD Assessment Test: a prospective analysis

BACKGROUND

The COPD Assessment Test (CAT) is responsive to change in patients with chronic obstructive pulmonary disease (COPD). However, the minimum clinically important difference (MCID) has not been established. We aimed to identify the MCID for the CAT using anchor-based and distribution-based methods.

METHODS

We did three studies at two centres in London (UK) between April 1, 2010, and Dec 31, 2012. Study 1 assessed CAT score before and after 8 weeks of outpatient pulmonary rehabilitation in patients with COPD who were able to walk 5 m, and had no contraindication to exercise. Study 2 assessed change in CAT score at discharge and after 3 months in patients admitted to hospital for more than 24 h for acute exacerbation of COPD. Study 3 assessed change in CAT score at baseline and at 12 months in stable outpatients with COPD. We focused on identifying the minimum clinically important improvement in CAT score. The St George's Respiratory Questionnaire (SGRQ) and Chronic Respiratory Questionnaire (CRQ) were measured concurrently as anchors. We used receiver operating characteristic curves, linear regression, and distribution-based methods (half SD, SE of measurement) to estimate the MCID for the CAT; we included only patients with paired CAT scores in the analysis.

FINDINGS

In Study 1, 565 of 675 (84%) patients had paired CAT scores. The mean change in CAT score with pulmonary rehabilitation was -2·5 (95% CI -3·0 to -1·9), which correlated significantly with change in SGRQ score (r=0·32; p<0·0001) and CRQ score (r=-0·46; p<0·0001). In Study 2, of 200 patients recruited, 147 (74%) had paired CAT scores. Mean change in CAT score from hospital discharge to 3 months after discharge was -3·0 (95% CI -4·4 to -1·6), which correlated with change in SGRQ score (r=0·47; p<0·0001). In Study 3, of 200 patients recruited, 164 (82%) had paired CAT scores. Although no significant change in CAT score was identified after 12 months (mean 0·6, 95% CI -0·4 to 1·5), change in CAT score correlated significantly with change in SGRQ score (r=0·36; p<0·0001). Linear regression estimated the minimum clinically important improvement for the CAT to range between -1·2 and -2·8 with receiver operating characteristic curves consistently identifying -2 as the MCID. Distribution-based estimates for the MCID ranged from -3·3 to -3·8.

INTERPRETATION

The most reliable estimate of the minimum important difference of the CAT is 2 points. This estimate could be useful in the clinical interpretation of CAT data, particularly in response to intervention studies.

FUNDING

Medical Research Council and UK National Institute of Health Research.

Integrin α1β1 differentially regulates cytokine-mediated responses in chondrocytes

OBJECTIVE

To elucidate the role of integrin α1β1 in chondrocyte responses to inflammatory interleukin-1α (IL-1) and anabolic transforming growth factor-β1 (TGF-β1) in the knee.

METHODS

Intracellular calcium transient responses to IL-1 and TGF-β1 were measured in wild type and integrin α1-null chondrocytes using real time ex vivo confocal microscopy, and immunohistochemistry was performed to analyze TGF-β1-mediated activation of Smad2/3 in tibial and femoral chondrocytes.

RESULTS

Loss of integrin α1β1 reduces intracellular calcium transient response to IL-1, while it enhances chondrocyte responses to TGF-β1 as measured by intracellular calcium transients and activation of downstream Smad2/3.

CONCLUSIONS

Integrin α1β1 plays a vital role in mediating chondrocyte responses to two contrasting factors that are critical players in the onset and progression of osteoarthritis - inflammatory IL-1 and anabolic TGF-β. Further investigation into the molecular mechanisms by which integrin α1β1 mediates these responses will be an important next step in understanding the influence of increased expression of integrin α1β1 during the early stages of osteoarthritis on disease progression.

The 4-metre gait speed in COPD: responsiveness and minimal clinically important difference

Usual gait speed is a consistent predictor of adverse outcomes in community-dwelling elderly people. The reliability and validity of the 4-m gait speed (4MGS) has recently been demonstrated in patients with chronic obstructive pulmonary disease (COPD). The aims of this study were to assess the responsiveness of the 4MGS and to estimate the minimal clinically important difference (MCID). In 301 COPD patients, 4MGS and incremental shuttle walk (ISW) were measured before and after pulmonary rehabilitation. 4MGS and ISW were also measured at baseline and 1 year later in a separate cohort of 162 COPD patients. The MCID of 4MGS was estimated using distribution and anchor-based methods. 4MGS improved significantly with pulmonary rehabilitation (mean change 0.08 m·s(-1), p<0.001). The minimal detectable change at 95% confidence was 0.11 m·s(-1). The MCID was estimated at 0.11 m·s(-1) (anchored against ISW) and 0.08 m·s(-1) (anchored against self-reported improvement). The effect size for 4MGS was greatest in frail individuals. After 12 months, mean 4MGS declined by 0.04 m·s(-1). When anchored against a decline of more than the MCID for ISW, change in 4MGS was -0.11 m·s(-1). The 4MGS is responsive to pulmonary rehabilitation and longitudinal change in COPD, and has potential as a simple functional assessment tool in COPD. The 4MGS may be particularly useful in frail individuals with COPD.

The Clinical COPD Questionnaire: response to pulmonary rehabilitation and minimal clinically important difference

BACKGROUND

The Clinical COPD Questionnaire (CCQ) is a simple 10-item, health-related quality of life questionnaire (HRQoL) with good psychometric properties. However, little data exists regarding the responsiveness of the CCQ to pulmonary rehabilitation (PR) or the minimal clinically important difference (MCID). The study aims were to assess the responsiveness of the CCQ to PR, to compare the responsiveness of the CCQ to other HRQoL questionnaires and to provide estimates for the MCID.

METHODS

The CCQ, St George's Respiratory Questionnaire (SGRQ), Chronic Respiratory Questionnaire (CRQ) and COPD Assessment Test (CAT) were measured in 261 patients with COPD before and after outpatient PR. Pre to post PR changes and Cohen's effect size were calculated. Changes in CCQ were compared with changes in other HRQoL questionnaires. Using an anchor-based approach and receiver operating characteristic (ROC) curves, the CCQ change cutoffs that identified patients achieving the known MCID for other health status questionnaires with PR were identified.

RESULTS

The CCQ, SGRQ, CRQ and CAT all significantly improved with PR with an effect size of -0.39, -0.33, 0.62 and -0.25, respectively. CCQ change correlated significantly with change in SGRQ, CRQ and CAT (r=0.48, -0.56, 0.54, respectively; all p<0.001). ROC curves consistently identified a CCQ change cutoff of -0.4 as the best discriminating value to identify the MCID for the SGRQ, CRQ and CAT (area under curve: 0.71, 0.75 and 0.77, respectively; all p<0.001).

CONCLUSIONS

The CCQ is responsive to PR with an estimated clinically important improvement of -0.4 points. The CCQ is a practical alternative to more time-consuming measures of HRQoL.