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2.
J Heart Lung Transplant ; 42(9): 1223-1232, 2023 09.
Article in English | MEDLINE | ID: mdl-37098374

ABSTRACT

BACKGROUND: Reduced arterial pulsatility in continuous-flow left ventricular assist devices (CF-LVAD) patients has been implicated in clinical complications. Consequently, recent improvements in clinical outcomes have been attributed to the "artificial pulse" technology inherent to the HeartMate3 (HM3) LVAD. However, the effect of the "artificial pulse" on arterial flow, transmission of pulsatility into the microcirculation and its association with LVAD pump parameters is not known. METHODS: The local flow oscillation (pulsatility index, PI) of common carotid arteries (CCAs), middle cerebral arteries (MCAs) and central retinal arteries (CRAs-representing the microcirculation) were quantified by 2D-aligned, angle-corrected Doppler ultrasound in 148 participants: healthy controls, n = 32; heart failure (HF), n = 43; HeartMate II (HMII), n = 32; HM3, n = 41. RESULTS: In HM3 patients, 2D-Doppler PI in beats with "artificial pulse" and beats with "continuous-flow" was similar to that of HMII patients across the macro- and microcirculation. Additionally, peak systolic velocity did not differ between HM3 and HMII patients. Transmission of PI into the microcirculation was higher in both HM3 (during the beats with "artificial pulse") and in HMII patients compared with HF patients. LVAD pump speed was inversely associated with microvascular PI in HMII and HM3 (HMII, r2 = 0.51, p < 0.0001; HM3 "continuous-flow," r2 = 0.32, p = 0.0009; HM3 "artificial pulse," r2 = 0.23, p = 0.007), while LVAD pump PI was only associated with microcirculatory PI in HMII patients. CONCLUSIONS: The "artificial pulse" of the HM3 is detectable in the macro- and microcirculation but without creating a significant alteration in PI compared with HMII patients. Increased transmission of pulsatility and the association between pump speed and PI in the microcirculation indicate that the future clinical care of HM3 patients may involve individualized pump settings according to the microcirculatory PI in specific end-organs.


Subject(s)
Heart Failure , Heart-Assist Devices , Humans , Microcirculation , Heart Failure/surgery , Heart Rate , Middle Cerebral Artery
3.
NPJ Prim Care Respir Med ; 32(1): 24, 2022 07 06.
Article in English | MEDLINE | ID: mdl-35794130

ABSTRACT

The Timed Up and Go (TUG) is a global measure of mobility and has the ability to detect frail individuals. Frail patients with chronic obstructive pulmonary disease (COPD) are usually undiagnosed. We hypothesised that the TUG would identify frail patients with COPD. Frailty was assessed in 520 patients diagnosed with COPD and 150 controls using a Comprehensive Geriatric Assessment questionnaire and frailty index (FI) was derived. The TUG was used to assess physical mobility. All participants were assessed for lung function and body composition. A ROC curve was used to identify how well TUG discriminates between frail and non-frail patients with COPD. The patients with COPD and controls were similar in age, sex and BMI but the patients with COPD were more frail, mean ± SD FI 0.16 ± 0.08 than controls 0.05 ± 0.03, P < 0.001. Frail patients with COPD had a greater TUG time (11.55 ± 4.03 s) compared to non-frail patients (9.2 ± 1.6 sec), after controlling for age and lung function (F = 15.94, P < 0.001), and both were greater than the controls (8.3 ± 1.2 sec), P < 0.001. The TUG discriminated between frail and non-frail patients with COPD with an area under the curve of 72 (95% CI: 67-76), and a diagnostic odds ratio of 2.67 (95% CI:1.5-4.6), P < 0.001. The TUG showed the ability to discriminate between frail and non-frail patients with COPD, independent of age and severity of the airflow obstruction. The TUG is a simple, easy and quick measure that could be easily applied in restricted settings to screen for frailty in COPD.


Subject(s)
Frailty , Pulmonary Disease, Chronic Obstructive , Aged , Frail Elderly , Frailty/diagnosis , Humans , Postural Balance , Pulmonary Disease, Chronic Obstructive/diagnosis , Time and Motion Studies
4.
J Heart Lung Transplant ; 41(6): 802-809, 2022 06.
Article in English | MEDLINE | ID: mdl-35422348

ABSTRACT

BACKGROUND: Limited data exist on the circadian blood pressure (BP) and heart rate (HR) variations that occur in heart failure (HF) patients on left ventricular assist device (LVAD) support. METHODS: We prospectively recorded clinic and 24-hour ambulatory BP and HR data in patients on HeartMate II LVAD support. Results were compared to HF patients with ejection fraction ≤30% and controls with no history of cardiovascular disease. Physiologic nocturnal BP and HR dipping was defined as a ≥10% decline compared to daytime values. RESULT: Twenty-nine LVAD patients (age 59 ± 15 years, 76% male, 38% ischemic etiology), 25 HF patients (age 64 ± 13 years, 84% male, 32% ischemic etiology) and 26 controls (age 56 ± 9 years, 62% male) were studied. Normal nocturnal BP dipping was less frequent in LVAD patients (10%) than in HF patients (28%) and controls (62%) and reversed BP dipping (BP increase at night) was more common in LVAD patients (24%), compared to HF (16%) and controls (8%), (p < 0.001, for all comparisons). Physiologic HR reduction was less frequent in LVAD patients (14%), compared to HF (16%) and controls (59%) (p < 0.001, for all comparisons). Among LVAD patients, 36% exhibited sustained hypertension over the 24-hours and 25% had white-coat hypertension. CONCLUSIONS: Treatment of advanced HF with an LVAD does not restore physiologic circadian variability of BP and HR; additionally, BP was not adequately controlled in more than a third of LVAD patients, and a quarter of them exhibited white-coat hypertension. Future studies are warranted to confirm these findings and investigate prognostic and management implications in this population.


Subject(s)
Heart Rate , Heart-Assist Devices , White Coat Hypertension , Adult , Aged , Blood Pressure , Blood Pressure Monitoring, Ambulatory , Female , Heart Failure/epidemiology , Heart Failure/surgery , Humans , Male , Middle Aged
5.
Prosthet Orthot Int ; 46(3): 258-266, 2022 Jun 01.
Article in English | MEDLINE | ID: mdl-35019886

ABSTRACT

BACKGROUND: Individuals with unilateral transtibial amputation are at risk of abnormal mechanical joint loading and development of osteoarthritis on sound side joint structures. OBJECTIVES: This study describes the spatiotemporal and kinetic and kinematic parameters related to osteoarthritis in participants while using (A) a solid-ankle cushioned-heel prosthesis (SACH), (B) a conventional energy storage and return (ESAR) foot prosthesis, and (C) a novel ESAR (N-ESAR) foot prosthesis. STUDY DESIGN: A pragmatic randomized controlled trial. METHODS: K3-K4 ambulators used three feet in a 2-week randomized cross-over order. Kinetics of vertical ground reaction forces (vGRFs) and 3D kinematics of joint angles were integrated to provide normalized parameters. Data were analyzed using one way and mixed model Analysis of variance (ANOVAs) (p < 0.05) and Cohen d statistic. RESULTS: Twenty participants, aged 40 ± 16 years with body mass index of 24.7 ± 3.6 kg/m2, experienced minimal change in the spatiotemporal parameters between feet. Participants using the N-ESAR foot prosthesis experienced reduced peak knee external adduction moment (p = 0.030), peak vGRFs (p < 0.001), and peak loading rate of vGRFs (p = 0.030). Peak knee flexion moments only changed when using the solid-ankle cushioned-heel prosthesis, in a positive direction (p = 0.014). Using the N-ESAR prosthesis also increased peak distal shank power during late stance phase (p < 0.001). CONCLUSIONS: A novel ankle/foot ESAR prosthesis reduces loading on the sound side. With extended use of the N-ESAR foot prosthesis, these findings may provide the prosthesis user with improved outcomes related to sound side loading and development of osteoarthritis.


Subject(s)
Artificial Limbs , Osteoarthritis , Ankle , Biomechanical Phenomena , Gait , Humans , Prosthesis Design
6.
Sports Biomech ; : 1-12, 2021 Oct 29.
Article in English | MEDLINE | ID: mdl-34713760

ABSTRACT

Force-time curves produced during a countermovement jump (CMJ) have traditionally been classified by visual observation as either unimodal (one concentric phase peak) or bimodal (two peaks). The association between CMJ modality and jump performance remains unclear and future studies may benefit from standardising and expanding modality classification. This study described a numerical method based on the timing and relative magnitude of concentric force-time curve prominences. Adult male elite rugby union players (n = 214) performed six CMJs on a force-instrumented treadmill and an algorithm using turning-point logic was applied to categorise jumps and define modality sub-groups. A sensitivity analysis demonstrated that the minimum prominence threshold (MPT) affected categorisation, as the proportion of bimodal jumps decreased with each 1% increase in MPT. Within-athlete consistency was also affected; between 43% and 63% of participants were consistently categorised as bimodal or unimodal depending on the selected MPT. Modified reactive strength index (RSImod), but not jump height or take-off momentum, was greater in unimodal jumps. Take-off momentum and RSImod were greater in subcategories where maximum force occurred early in the concentric phase. Future research should implement objective classification methods to enhance transparency and comparability and consider subcategories to investigate CMJ force production strategies.

7.
ERJ Open Res ; 7(3)2021 Jul.
Article in English | MEDLINE | ID: mdl-34476245

ABSTRACT

RATIONALE: COPD and smoking are characterised by pulmonary inflammation. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) imaging may improve knowledge of pulmonary inflammation in COPD patients and aid early development of novel therapies as an imaging biomarker. OBJECTIVES: To evaluate pulmonary inflammation, assessed by FDG uptake, in whole and regional lung in "usual" (smoking-related) COPD patients, alpha-1 antitrypsin deficiency (α1ATD) COPD patients, smokers without COPD and never-smokers using FDG PET/CT. Secondly, to explore cross-sectional associations between FDG PET/CT and systemic inflammatory markers in COPD patients and repeatability of the technique in COPD patients. METHODS: Data from two imaging studies were evaluated. Pulmonary FDG uptake (normalised Ki; nKi) was measured by Patlak graphical analysis in four subject groups: 84 COPD patients, 11 α1ATD-COPD patients, 12 smokers and 10 never-smokers. Within the COPD group, associations between nKi and systemic markers of inflammation were assessed. Repeatability was evaluated in 32 COPD patients comparing nKi values at baseline and at 4-month follow-up. RESULTS: COPD patients, α1ATD-COPD patients and smokers had increased whole lung FDG uptake (nKi) compared with never-smokers (0.0037±0.001, 0.0040±0.001, 0.0040±0.001 versus 0.0028±0.001 mL·cm-3·min-1, respectively, p<0.05 for all). Similar results were observed in upper and middle lung regions. In COPD participants, plasma fibrinogen was associated with whole lung nKi (ß=0.30, p=0.02) in multivariate analysis adjusted for current smoking, forced expiratory volume in 1 s % predicted, systemic neutrophils and C-reactive protein levels. Mean percentage difference in nKi between the baseline and follow-up was 3.2%, and the within subject coefficient of variability was 7.7%. CONCLUSIONS: FDG PET/CT has potential as a noninvasive tool to enable whole lung and regional quantification of FDG uptake to assess smoking- and COPD-related pulmonary inflammation.

8.
J Heart Lung Transplant ; 40(8): 786-793, 2021 08.
Article in English | MEDLINE | ID: mdl-34134913

ABSTRACT

BACKGROUND: While rates of stroke have declined with the HeartMate3 (HM3) continuous- flow (CF) left ventricular assist device (LVAD), the impact of non-pulsatile flow and artificial pulse physiology on cerebrovascular function is not known. We hypothesized that improved hemodynamics and artificial pulse physiology of HM3 patients would augment cerebrovascular metabolic reactivity (CVR) compared with HeartMate II (HMII) CF-LVAD and heart failure (HF) patients. METHODS: Mean, peak systolic and diastolic flow velocities (MFV, PSV, MinFV, respectively) and cerebral pulsatility index were determined in the middle cerebral artery (MCA) before and after a 30 sec breath-hold challenge in 90 participants: 24 healthy controls; 30 HF, 15 HMII, and 21 HM3 patients. RESULTS: In HM3 patients, breath-holding increased MFV (Δ8 ± 10 cm/sec, p < .0001 vs baseline) to levels similar to HF patients (Δ9 ± 8 cm/sec, p > .05), higher than HMII patients (Δ2 ± 8 cm/sec, p < .01) but lower than healthy controls (Δ13 ± 7 cm/sec, p < .05). CF-LVAD altered the proportion of systolic and diastolic flow responses as reflected by a differential cerebral pulsatility index (p = .03). Baseline MFV was not related to CVR (r2 = 0.0008, p = .81). However, CF-LVAD pump speed was strongly inversely associated with CVR in HM II (r2 = 0.51, p = .003) but not HM3 patients (r2 = 0.01, p = .65). CONCLUSIONS: Compared with HMII, HM3 patients have a significantly improved CVR. However, CVR remains lower in HM3 and HF patients than in healthy controls, therefore suggesting that changes in cerebral hemodynamics are not reversed by CF-LVAD therapy. Further research on the mechanisms and the long-term impact of altered cerebral hemodynamics in this unique patient population are warranted.


Subject(s)
Cerebrovascular Circulation/physiology , Heart Failure/physiopathology , Heart-Assist Devices , Middle Cerebral Artery/physiopathology , Pulsatile Flow/physiology , Ultrasonography, Doppler, Transcranial/methods , Vasodilation/physiology , Diastole , Equipment Design , Female , Heart Failure/diagnosis , Heart Failure/surgery , Homeostasis , Humans , Male , Middle Aged , Middle Cerebral Artery/diagnostic imaging , Regional Blood Flow/physiology , Stroke Volume/physiology
9.
Eur Heart J Suppl ; 23(Suppl B): B147-B150, 2021 May.
Article in English | MEDLINE | ID: mdl-34054372

ABSTRACT

In the UK, heart and circulatory diseases account for 29% of all deaths (14% through coronary heart disease and 8% through stroke). In 2015, the prevalence of hypertension was 20% in the UK and 23% in the Republic of Ireland. In 2019, 14% of people registered with a UK general practice had hypertension and yet it was the attributable risk factor for around half of all deaths from coronary heart disease or stroke. We participated in May Measurement Month 2019 to increase awareness of blood pressure (BP) measurement, and to identify the proportion of undiagnosed hypertension and degree of uncontrolled hypertension in the community. The 2019 campaign set up screening sites within the community at places of worship, supermarkets, GP surgeries, workplaces, charity events, community pharmacies, gyms, and various other public places. We screened 10194 participants (mean age 51 ± 18 years, 60% women) and found that 1013 (9.9%) were on antihypertensive treatment, while 3408 (33.4%) had hypertension. Of the 3408 participants with hypertension, only 33.5% were aware of their condition despite 98.8% having previous BP measurements. In those on antihypertensive medication, only 38.2% had controlled BP (<140 and <90 mmHg). Our UK and Republic of Ireland data demonstrate concerning levels of undiagnosed hypertension and sub-optimal BP control in many individuals with a diagnosis. This evidence supports a critical need for better systematic community and primary care screening initiatives.

10.
J Card Fail ; 27(6): 696-699, 2021 06.
Article in English | MEDLINE | ID: mdl-33639317

ABSTRACT

BACKGROUND: In the general population, increased aortic stiffness is associated with an increased risk of cardiovascular events. Previous studies have demonstrated an increase in aortic stiffness in patients with a continuous flow left ventricular assist device (CF-LVAD). However, the association between aortic stiffness and common adverse events is unknown. METHODS AND RESULTS: Forty patients with a HeartMate II (HMII) (51 $ 11 years; 20% female; 25% ischemic) implanted between January 2011 and September 2017 were included. Two-dimensional transthoracic echocardiograms of the ascending aorta, obtained before HMII placement and early after heart transplant, were analyzed to calculate the aortic stiffness index (AO-SI). The study cohort was divided into patients who had an increased vs decreased AO-SI after LVAD support. A composite outcome of gastrointestinal bleeding, stroke, and pump thrombosis was defined as the primary end point and compared between the groups. While median AO-SI increased significantly after HMII support (AO-SI 4.4-6.5, P = .012), 16 patients had a lower AO-SI. Patients with increased (n = 24) AO-SI had a significantly higher rate of the composite end point (58% vs 12%, odds ratio 9.8, P < .01). Similarly, those with increased AO-SI tended to be on LVAD support for a longer duration, had higher LVAD speed and reduced use of angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers. CONCLUSIONS: Increased aortic stiffness in patients with a HMII is associated with a significantly higher rates of adverse events. Further studies are warranted to determine the causality between aortic stiffness and adverse events, as well as the effect of neurohormonal modulation on the conduit vasculature in patients with a CF-LVAD.


Subject(s)
Heart Failure , Heart-Assist Devices , Stroke , Thrombosis , Vascular Stiffness , Female , Gastrointestinal Hemorrhage/diagnosis , Gastrointestinal Hemorrhage/epidemiology , Gastrointestinal Hemorrhage/etiology , Heart Failure/epidemiology , Heart-Assist Devices/adverse effects , Humans , Male , Retrospective Studies , Stroke/epidemiology , Stroke/etiology , Thrombosis/diagnostic imaging , Thrombosis/epidemiology , Thrombosis/etiology
11.
Exp Brain Res ; 239(4): 1193-1202, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33570677

ABSTRACT

Mobile Electroencephalography (EEG) provides insights into cortical contributions to postural control. Although changes in theta (4-8 Hz) and alpha frequency power (8-12 Hz) were shown to reflect attentional and sensorimotor processing during balance tasks, information about the effect of stance leg on cortical processing related to postural control is lacking. Therefore, the aim was to examine patterns of cortical activity during single-leg stance with varying surface stability. EEG and force plate data from 21 healthy males (22.43 ± 2.23 years) was recorded during unipedal stance (left/right) on a stable and unstable surface. Using source-space analysis, power spectral density was analyzed in the theta, alpha-1 (8-10 Hz) and alpha-2 (10-12 Hz) frequency bands. Repeated measures ANOVA with the factors leg and surface stability revealed significant interaction effects in the left (p = 0.045, ηp2 = 0.13) and right motor clusters (F = 16.156; p = 0.001, ηp2 = 0.41). Furthermore, significant main effects for surface stability were observed for the fronto-central cluster (theta), left and right motor (alpha-1), as well as for the right parieto-occipital cluster (alpha-1/alpha-2). Leg dependent changes in alpha-2 power may indicate lateralized patterns of cortical processing in motor areas during single-leg stance. Future studies may therefore consider lateralized patterns of cortical activity for the interpretation of postural deficiencies in unilateral lower limb injuries.


Subject(s)
Leg , Motor Cortex , Attention , Electroencephalography , Humans , Male , Postural Balance
12.
Age Ageing ; 50(3): 795-801, 2021 05 05.
Article in English | MEDLINE | ID: mdl-32894757

ABSTRACT

RATIONALE: chronic obstructive pulmonary disease (COPD) is a leading cause of mortality and common in older adults. The BODE Index is the most recognised mortality risk score in COPD but includes a 6-minute walk test (6MWT) that is seldom available in practise; the BODE Index may be better adopted if the 6MWT was replaced. OBJECTIVES: we investigated whether a modified BODE Index in which 6MWT was replaced by an alternative measure of physical capacity, specifically the short physical performance battery (SPPB) or components, retained its predictive ability for mortality in individuals with COPD. METHODS: we analysed 630 COPD patients from the ERICA cohort study for whom UK Office for National Statistics verified mortality data were available. Variables tested at baseline included spirometry, 6MWT, SPPB and its components (4-m gait speed test [4MGS], chair stand and balance). Predictive models were developed using stratified multivariable Cox regression, and assessed by C-indices and calibration plots with 10-fold cross-validation and replication. RESULTS: during median 2 years of follow-up, 60 (10%) individuals died. There was no significant difference between the discriminative ability of BODE6MWT (C-index 0.709, 95% confidence interval [CI], 0.680-0.737), BODESPPB (C-index 0.683, 95% CI, 0.647-0.712), BODE4MGS (C-index 0.676, 95% CI, 0.643-0.700) and BODEBALANCE (C-index 0.686, 95% CI, 0.651-0.713) for predicting mortality. CONCLUSIONS: the SPPB, and its 4MGS and balance components, can potentially be used as an alternative to the 6MWT in the BODE Index without significant loss of predictive ability in all-cause mortality.


Subject(s)
Pulmonary Disease, Chronic Obstructive , Aged , Cohort Studies , Exercise Tolerance , Gait , Humans , Physical Functional Performance , Pulmonary Disease, Chronic Obstructive/diagnosis , Severity of Illness Index , Walk Test
13.
Med Sci Sports Exerc ; 53(5): 1010-1020, 2021 05 01.
Article in English | MEDLINE | ID: mdl-33148970

ABSTRACT

PURPOSE: The increased physiological demand of pregnancy results in the profound adaptation of the maternal cardiovascular system, reflected by greater resting cardiac output and left ventricular (LV) deformation. Whether the increased resting demand alters acute cardiac responses to exercise in healthy pregnant women is not well understood. METHODS: Healthy nonpregnant (n = 18), pregnant (n = 14, 22-26 wk gestation), and postpartum women (n = 13, 12-16 wk postdelivery) underwent assessments of cardiac function and LV mechanics at rest, during a sustained isometric forearm contraction (30% maximum), and during low-intensity (LOW) and moderate-intensity (MOD) dynamic cycling exercise (25% and 50% peak power output). Significant differences (α = 0.05) were determined using ANCOVA and general linear model (resting value included as covariate). RESULTS: When accounting for higher resting cardiac output in pregnant women, pregnant women had greater cardiac output during isometric contraction (2.0 ± 0.3 L·min-1·m-1.83; nonpregnant, 1.3 ± 0.2 L·min-1·m-1.83; postpartum, 1.5 ± 0.5 L·min-1·m-1.83; P = 0.02) but similar values during dynamic cycling exercise (pregnant, LOW = 2.8 ± 0.4 L·min-1·m-1.83, MOD = 3.4 ± 0.7 L·min-1·m-1.83; nonpregnant, LOW = 2.4 ± 0.3 L·min-1·m-1.83, MOD = 3.0 ± 0.3 L·min-1·m-1.83; postpartum, LOW = 2.3 ± 0.4 L·min-1·m-1.83, MOD = 3.0 ± 0.5 L·min-1·m-1.83; P = 0.96). Basal circumferential strain was higher in pregnant women at rest, during the sustained isometric forearm contraction (-23.5% ± 1.2%; nonpregnant, -14.6% ± 1.4%; P = 0.001), and during dynamic cycling exercise (LOW = -27.0% ± 4.9%, MOD = -27.4% ± 4.6%; nonpregnant, LOW = -15.8% ± 4.5%, MOD = -15.2% ± 6.7%; P = 0.012); however, other parameters of LV mechanics were not different between groups. CONCLUSION: The results support that the maternal heart can appropriately respond to additional cardiac demand and altered loading experienced during acute isometric and dynamic exercise, although subtle differences in responses to these challenges were observed. In addition, the LV mechanics that underpin global cardiac function are greater in pregnant women during exercise, leading to the speculation that the hormonal milieu of pregnancy influences regional deformation.


Subject(s)
Cardiac Output/physiology , Exercise/physiology , Isometric Contraction/physiology , Rest/physiology , Ventricular Function, Left/physiology , Adaptation, Physiological , Adult , Bicycling/physiology , Blood Pressure/physiology , Female , Forearm/physiology , Guideline Adherence/statistics & numerical data , Humans , Linear Models , Postpartum Period , Pregnancy , Pregnant Women
14.
BMJ Open ; 10(12): e038360, 2020 12 28.
Article in English | MEDLINE | ID: mdl-33372069

ABSTRACT

OBJECTIVES: Although cardiovascular disease (CVD) is a common comorbidity associated with chronic obstructive pulmonary disease (COPD), it is unknown how to improve prediction of cardiovascular (CV) risk in individuals with COPD. Traditional CV risk scores have been tested in different populations but not uniquely in COPD. The potential of alternative markers to improve CV risk prediction in individuals with COPD is unknown. We aimed to determine the predictive value of conventional CVD risk factors in COPD and to determine if additional markers improve prediction beyond conventional factors. DESIGN: Data from the Evaluation of the Role of Inflammation in Chronic Airways disease cohort, which enrolled 729 individuals with Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage II-IV COPD were used. Linked hospital episode statistics and survival data were prospectively collected for a median 4.6 years of follow-up. SETTING: Five UK centres interested in COPD. PARTICIPANTS: Population-based sample including 714 individuals with spirometry-defined COPD, smoked at least 10 pack years and who were clinically stable for >4 weeks. INTERVENTIONS: Baseline measurements included aortic pulse wave velocity (aPWV), carotid intima-media thickness (CIMT), C reactive protein (CRP), fibrinogen, spirometry and Body mass index, airflow Obstruction, Dyspnoea and Exercise capacity (BODE) Index, 6 min walk test (6MWT) and 4 m gait speed (4MGS) test. PRIMARY AND SECONDARY OUTCOME MEASURES: New occurrence (first event) of fatal or non-fatal hospitalised CVD, and all-cause and cause-specific mortality. RESULTS: Out of 714 participants, 192 (27%) had CV hospitalisation and 6 died due to CVD. The overall CV risk model C-statistic was 0.689 (95% CI 0.688 to 0.691). aPWV and CIMT neither had an association with study outcome nor improved model prediction. CRP, fibrinogen, GOLD stage, BODE Index, 4MGS and 6MWT were associated with the outcome, independently of conventional risk factors (p<0.05 for all). However, only 6MWT improved model discrimination (C=0.727, 95% CI 0.726 to 0.728). CONCLUSION: Poor physical performance defined by the 6MWT improves prediction of CV hospitalisation in individuals with COPD. TRIAL REGISTRATION NUMBER: ID 11101.


Subject(s)
Cardiovascular Diseases , Pulmonary Disease, Chronic Obstructive , Cardiovascular Diseases/epidemiology , Carotid Intima-Media Thickness , Heart Disease Risk Factors , Humans , Physical Functional Performance , Pulmonary Disease, Chronic Obstructive/complications , Pulmonary Disease, Chronic Obstructive/epidemiology , Pulse Wave Analysis , Risk Factors
15.
J Bodyw Mov Ther ; 24(4): 251-260, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33218520

ABSTRACT

INTRODUCTION: Wearable inertial measurement units (IMUs) enable gait analysis in the clinic, but require calibrations that may affect subsequent gait measurements. This study assessed concurrent validity and within-session reliability of gait kinematics measured by a frequently calibrated IMU-based system. Calibration pose accuracy and intra-rater repeatability, and IMU orientation tracking accuracy, were additionally quantified. METHODS: Calibration poses and gait were recorded in 15 women using IMUs and optical motion capture (OMC) (reference standard) simultaneously. Participants performed six consecutive trials: each comprising a calibration pose and a walk. IMU tracking was assessed separately (once-off) using technical static and dynamic tests. Differences of > 5° constituted clinical significance. RESULTS: Concurrent validity for gait revealed clinically significant between-system differences for sagittal angles (root-mean-square error [RMSE] 6.7°-15.0°; bias -9.3°-3.0°) and hip rotation (RMSE 7.9°; bias -4.2°). After removing modelling offsets, differences for all angles (except hip rotation) were < 5°. Gait curves correlated highly between systems (r > 0.8), except hip rotation, pelvic tilt and -obliquity. Within-session reliability of IMU-measured gait angles was clinically acceptable (standard error of measurement [SEM] < 5°). Calibration poses were repeatable (SEM 0.3°-2.2°). Pose accuracy revealed mean absolute differences (MAD) < 5° for all angles except sagittal ankle, hip and pelvis. IMU tracking accuracy demonstrated RMSE ≤ 2.0°. CONCLUSION: A frequently calibrated IMU system provides reliable gait measurements; comparing highly to OMC after removing modelling differences. Calibration poses can be implemented accurately for most angles and consistently. IMU-measured gait data are clinically useful and comparable within participants, but should not be compared to OMC-measured data.


Subject(s)
Gait , Biomechanical Phenomena , Calibration , Female , Humans , Range of Motion, Articular , Reproducibility of Results
16.
J Bodyw Mov Ther ; 24(4): 303-315, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33218527

ABSTRACT

BACKGROUND: This study compared dynamic postural stability (DPS) and lower limb kinematics during single leg hopping (SLH) performed by typically-developed children from urban and rural settings and children with Fetal Alcohol Spectrum Disorder (FASD) from a rural setting. METHODS: Typically-developed nine-year-old children from an urban (n = 27) and rural setting (n = 14) (controls), and nine-year-old children with FASD from a rural setting (n = 14) (cases) performed SLH and landing on a pressure mat. Motion analysis systems described 1) Spatiotemporal and centre of pressure parameters (COP) and lower limb sagittal plane kinematics. Descriptive results are presented in median and ranges and differences between groups were determined by Kruskal-Wallis and Mann-Whitney U statistical tests. The level of significance was p < 0.05. RESULTS: During hopping, the urban controls had longer stance and swing times (p < 0.001) than the rural groups. The urban controls remained in greater hip flexion compared to the case group (p = 0.02). The urban controls landed in more plantarflexion at initial foot contact (IFC) than the cases (p < 0.001) and the rural controls (p = 0.03). The rural groups landed with greater knee extension at IFC than the urban controls (cases p = 0.04; rural controls p < 0.001). During the landing motion, the urban controls moved into more hip flexion compared to the cases (p = 0.015) and the rural controls (p = 0.026). The cases displayed greater COP anteroposterior values during landing compared to both control groups, but the case group displayed the fastest time to stability. CONCLUSION: The different hopping strategies observed provides an indication of the movement capabilities of these groups.


Subject(s)
Anterior Cruciate Ligament Injuries , Fetal Alcohol Spectrum Disorders , Biomechanical Phenomena , Child , Female , Humans , Leg , Movement , Pregnancy
17.
J Am Heart Assoc ; 9(7): e014375, 2020 04 09.
Article in English | MEDLINE | ID: mdl-33044913

ABSTRACT

Background Two individuals can have a similar pulse pressure (PP) but different levels of systolic blood pressure (SBP), although the underlying mechanisms have not been described. We hypothesized that, for a given level of PP, differences in SBP relate to peripheral vascular resistance (PVR); and we tested this hypothesis in a large cohort of healthy young adults. Methods and Results Demographic, biochemical, and hemodynamic data from 3103 subjects were available for the current analyses. In both men and women, for a given level of PP, higher SBP was associated with significantly higher body weight, body mass index, heart rate, and PVR (P<0.05 versus those with lower BP for all comparisons). Moreover, stratifying individuals by quartiles of PP and PVR revealed a stepwise increase in SBP from the lowest to highest quartile for each variable, with the highest SBP occurring in those in the highest quartile of both PP and PVR (P<0.001 for overall trend for both sexes). PVR was also increased with increasing tertile of minimum forearm vascular resistance, in both men (P=0.002) and women (P=0.03). Conclusions Increased PVR, mediated in part through altered resistance vessel structure, strongly associates with the elevation of SBP for a given level of PP in young adults. An impaired ability to adapt PVR appropriately to a given level of PP may be an important mechanism underlying elevated SBP in young adults.


Subject(s)
Blood Pressure , Upper Extremity/blood supply , Vascular Resistance , Adaptation, Physiological , Adolescent , Adult , Age Factors , Cross-Sectional Studies , Female , Humans , Male , Young Adult
18.
Eur Heart J Suppl ; 22(Suppl H): H132-H134, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32884493

ABSTRACT

Raised blood pressure (BP) was the biggest contributor to the global burden of disease in 2017, with lack of awareness and adequate control of BP identified as the main drivers of this disease burden. In 2017, an opportunistic BP screening and awareness campaign called May Measurement Month (MMM) in the UK and Republic of Ireland (RoI) highlighted that levels of undiagnosed hypertension and uncontrolled hypertension in the community screened were approximately 23% and 40%, respectively. MMM18 was undertaken to further the campaign's efforts to increase awareness and create an evidence base of population risk associated with high BP. MMM18 BP screenings were conducted in the community at places of worship, supermarkets, GP surgeries, workplaces, community pharmacies, gyms, and various other public places. A total of 5000 volunteers, aged 47.3 (±17.2) years, 60% female were screened. Of all 5000 individuals screened, 1716 (34.3%) were hypertensive, of which only 51.3% were aware of their condition, 42.8% on antihypertensive treatment, and only 51.5% of those on medication controlled to target BP of <140/90 mmHg. Furthermore, obese, overweight, and underweight participants all had significantly higher BP values compared to individuals with a healthy body mass index (BMI). The 2018 MMM campaign in the UK and the RoI confirmed approximately one in three adults were hypertensive, with more than half having uncontrolled BP. In addition, these findings show that people with low BMI are at risk of having high BP. Finally, with only one in two people aware of their high BP, awareness remains a significant public health concern.

19.
Clin J Am Soc Nephrol ; 15(9): 1330-1339, 2020 09 07.
Article in English | MEDLINE | ID: mdl-32843374

ABSTRACT

BACKGROUND AND OBJECTIVES: The Effect of a Reduction in GFR after Nephrectomy on Arterial Stiffness and Central Hemodynamics (EARNEST) study was a multicenter, prospective, controlled study designed to investigate the associations of an isolated reduction in kidney function on BP and arterial hemodynamics. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Prospective living kidney donors and healthy controls who fulfilled criteria for donation were recruited from centers with expertise in vascular research. Participants underwent office and ambulatory BP measurement, assessment of arterial stiffness, and biochemical tests at baseline and 12 months. RESULTS: A total of 469 participants were recruited, and 306 (168 donors and 138 controls) were followed up at 12 months. In the donor group, mean eGFR was 27 ml/min per 1.73 m2 lower than baseline at 12 months. Compared with baseline, at 12 months the mean within-group difference in ambulatory day systolic BP in donors was 0.1 mm Hg (95% confidence interval, -1.7 to 1.9) and 0.6 mm Hg (95% confidence interval, -0.7 to 2.0) in controls. The between-group difference was -0.5 mm Hg (95% confidence interval, -2.8 to 1.7; P=0.62). The mean within-group difference in pulse wave velocity in donors was 0.3 m/s (95% confidence interval, 0.1 to 0.4) and 0.2 m/s (95% confidence interval, -0.0 to 0.4) in controls. The between-group difference was 0.1 m/s (95% confidence interval, -0.2 to 0.3; P=0.49). CONCLUSIONS: Changes in ambulatory peripheral BP and pulse wave velocity in kidney donors at 12 months after nephrectomy were small and not different from controls. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: NCT01769924 (https://clinicaltrials.gov/ct2/show/NCT01769924).


Subject(s)
Arterial Pressure , Kidney Transplantation , Living Donors , Nephrectomy , Vascular Stiffness , Adult , Blood Pressure Monitoring, Ambulatory , Case-Control Studies , Female , Glomerular Filtration Rate , Humans , Kidney Transplantation/adverse effects , Longitudinal Studies , Male , Middle Aged , Nephrectomy/adverse effects , Prospective Studies , Pulse Wave Analysis , Time Factors , Treatment Outcome
20.
Biomed Eng Online ; 19(1): 57, 2020 Jul 24.
Article in English | MEDLINE | ID: mdl-32709239

ABSTRACT

BACKGROUND: Inertial measurement unit (IMU)-based motion capture systems are gaining popularity for gait analysis outside laboratories. It is important to determine the performance of such systems in specific patient populations. We aimed to validate and determine within-day reliability of an IMU system for measuring lower limb gait kinematics and temporal-spatial parameters (TSP) in people with and without HIV. METHODS: Gait was recorded in eight adults with HIV (PLHIV) and eight HIV-seronegative participants (SNP), using IMUs and optical motion capture (OMC) simultaneously. Participants performed six gait trials. Fifteen TSP and 28 kinematic angles were extracted. Intraclass correlations (ICC), root-mean-square error (RMSE), mean absolute percentage error and Bland-Altman analyses were used to assess concurrent validity of the IMU system (relative to OMC) separately in PLHIV and SNP. IMU reliability was assessed during within-session retest of trials. ICCs were used to assess relative reliability. Standard error of measurement (SEM) and percentage SEM were used to assess absolute reliability. RESULTS: Between-system TSP differences demonstrated acceptable-to-excellent ICCs (0.71-0.99), except for double support time and temporophasic parameters (< 0.60). All TSP demonstrated good mean absolute percentage errors (≤7.40%). For kinematics, ICCs were acceptable to excellent (0.75-1.00) for all but three range of motion (ROM) and four discrete angles. RMSE and bias were 0.0°-4.7° for all but two ROM and 10 discrete angles. In both groups, TSP reliability was acceptable to excellent for relative (ICC 0.75-0.99) (except for one temporal and two temporophasic parameters) and absolute (%SEM 1.58-15.23) values. Reliability trends of IMU-measured kinematics were similar between groups and demonstrated acceptable-to-excellent relative reliability (ICC 0.76-0.99) and clinically acceptable absolute reliability (SEM 0.7°-4.4°) for all but two and three discrete angles, respectively. Both systems demonstrated similar magnitude and directional trends for differences when comparing the gait of PLHIV with that of SNP. CONCLUSIONS: IMU-based gait analysis is valid and reliable when applied in PLHIV; demonstrating a sufficiently low precision error to be used for clinical interpretation (< 5° for most kinematics; < 20% for TSP). IMU-based gait analysis is sensitive to subtle gait deviations that may occur in PLHIV.


Subject(s)
Gait Analysis , HIV Infections/physiopathology , Mechanical Phenomena , Spatio-Temporal Analysis , Adult , Biomechanical Phenomena , Female , Humans , Male
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